A health economic model for the development and evaluation of innovations in aged care: an application to consumer-directed care-study protocol.

PubMed

Ratcliffe, Julie; Lancsar, Emily; Luszcz, Mary; Crotty, Maria; Gray, Len; Paterson, Jan; Cameron, Ian D

2014-06-25

Consumer-directed care is currently being embraced within Australia and internationally as a means of promoting autonomy and choice in the delivery of health and aged care services. Despite its wide proliferation little research has been conducted to date to assess the views and preferences of older people for consumer-directed care or to assess the costs and benefits of such an approach relative to existing models of service delivery. A comprehensive health economic model will be developed and applied to the evolution, implementation and evaluation of consumer-directed care in an Australian community aged care setting. A mixed methods approach comprising qualitative interviews and a discrete choice experiment will determine the attitudes and preferences of older people and their informal carers for consumer-directed care. The results of the qualitative interviews and the discrete choice experiment will inform the introduction of a new consumer-directed care innovation in service delivery. The cost-effectiveness of consumer-directed care will be evaluated by comparing incremental changes in resource use, costs and health and quality of life outcomes relative to traditional services. The discrete choice experiment will be repeated at the end of the implementation period to determine the extent to which attitudes and preferences change as a consequence of experience of consumer-directed care. The proposed framework will have wide applicability in the future development and economic evaluation of new innovations across the health and aged care sectors. The study is approved by Flinders University Social and Behavioural Research Ethics Committee (Project No. 6114/SBREC). Findings from the qualitative interviews, discrete choice experiments and the economic evaluation will be reported at a workshop of stakeholders to be held in 2015 and will be documented in reports and in peer reviewed journal articles. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Decision heuristic or preference? Attribute non-attendance in discrete choice problems.

PubMed

Heidenreich, Sebastian; Watson, Verity; Ryan, Mandy; Phimister, Euan

2018-01-01

This paper investigates if respondents' choice to not consider all characteristics of a multiattribute health service may represent preferences. Over the last decade, an increasing number of studies account for attribute non-attendance (ANA) when using discrete choice experiments to elicit individuals' preferences. Most studies assume such behaviour is a heuristic and therefore uninformative. This assumption may result in misleading welfare estimates if ANA reflects preferences. This is the first paper to assess if ANA is a heuristic or genuine preference without relying on respondents' self-stated motivation and the first study to explore this question within a health context. Based on findings from cognitive psychology, we expect that familiar respondents are less likely to use a decision heuristic to simplify choices than unfamiliar respondents. We employ a latent class model of discrete choice experiment data concerned with National Health Service managers' preferences for support services that assist with performance concerns. We present quantitative and qualitative evidence that in our study ANA mostly represents preferences. We also show that wrong assumptions about ANA result in inadequate welfare measures that can result in suboptimal policy advice. Future research should proceed with caution when assuming that ANA is a heuristic. Copyright © 2017 John Wiley & Sons, Ltd.

Do patients prefer mesh or anterior colporrhaphy for primary correction of anterior vaginal wall prolapse: a labelled discrete choice experiment.

PubMed

Notten, K J B; Essers, B A; Weemhoff, M; Rutten, A G H; Donners, J J A E; van Gestel, I; Kruitwagen, R F P M; Roovers, J P W R; Dirksen, C D

2015-05-01

We investigated patients' preferences for anterior colporrhaphy or mesh surgery as surgical correction of anterior vaginal wall prolapse. Labelled discrete choice experiment. Three Dutch teaching hospitals. Women with anterior vaginal wall prolapse Pelvic Organ Prolapse Quantification stage 2 or more, indicated for anterior colporrhaphy (n = 100). Discrete choice experiments are an attribute-based survey method for measuring preferences. In this experiment, women were asked to choose between two treatment scenarios, mesh surgery or anterior colporrhaphy. These surgical treatments differed in four treatment attributes: (i) recurrence rate, (ii) exposure rate, (iii) infection rate, (iv) dyspareunia. Data were analysed using a multinomial logit model. Women's preferences for anterior colporrhaphy or mesh surgery for the repair of vaginal wall prolapse. All treatment attributes, i.e. recurrence, exposure, infection and dyspareunia, proved to be significant in the woman's decision to choose mesh surgery (P < 0.001), while only two attributes out of three, recurrence and infection, were significant for anterior colporrhaphy (P < 0.001). The relative importance data showed that with regards to the four statistically significant attributes for mesh, dyspareunia was the most important attribute, and of the two significant attributes for anterior colporrhaphy, the risk of infection. Based on the attributes and levels in our discrete choice experiment, anterior colporrhaphy was preferred in 74% as a primary correction of anterior vaginal wall prolapse, followed by a preference for mesh in 26% of all choices. This study showed that next to the risk of recurrence, other aspects like risk of infection, dyspareunia and exposure play a role in the woman's preference for a surgical treatment. In addition, our results indicate that anterior colporrhaphy is preferred in the majority of the choices, followed by a preference for mesh surgery in a quarter of all choice sets. However, these results represent the average preference of a sample of women and cannot be taken as the preference of each individual. In the medical decision-making context, information from the current study should be personalised to fit patient's unique circumstances. For patients to construct their own, individual preferences, they should be well informed about the existence and magnitude of the potential benefits and risks related to either anterior colporrhaphy or mesh surgery. © 2014 Royal College of Obstetricians and Gynaecologists.

A discrete choice experiment to determine UK patient preference for attributes of disease modifying treatments in Multiple Sclerosis.

PubMed

Bottomley, Catherine; Lloyd, Andrew; Bennett, Gary; Adlard, Nicholas

2017-08-01

The recent licensing of Disease Modifying Treatments (DMTs) for Multiple Sclerosis (MS) has increased available treatment options. The aim of this study was to explore MS patients' preference for the different attributes of DMTs in the UK. Attributes (treatment characteristics) for inclusion in the discrete choice experiment (DCE) were determined through published literature and interviews with 12 people with MS. Seven attributes were selected. Participants were presented with three hypothetical treatment options sampled from included attributes and asked for their most/least preferred options. The influence of patient characteristics and demographics on patient preference was also investigated. The DCE was completed by 350 people with MS (81% female, mean age = 39). Results showed that method of taking medication was the strongest determinant of preference (27%; relative importance out of 100%), followed by relapse free rate (21%) and symptom progression (14%). Risk of fatigue (8%) and type of monitoring (6%) were the weakest determinants of preference. Once-daily oral treatment was preferred over all other methods of administration. Participant characteristics did not influence data on strength of preference. This study assumed adequate participant understanding of the discrete choice experiment task, and recruitment targeted those with access to the internet. These results, derived from people with MS in the UK, should be used to inform individual discussions with patients about DMT choices.

Are Health State Valuations from the General Public Biased? A Test of Health State Reference Dependency Using Self-assessed Health and an Efficient Discrete Choice Experiment.

PubMed

Jonker, Marcel F; Attema, Arthur E; Donkers, Bas; Stolk, Elly A; Versteegh, Matthijs M

2017-12-01

Health state valuations of patients and non-patients are not the same, whereas health state values obtained from general population samples are a weighted average of both. The latter constitutes an often-overlooked source of bias. This study investigates the resulting bias and tests for the impact of reference dependency on health state valuations using an efficient discrete choice experiment administered to a Dutch nationally representative sample of 788 respondents. A Bayesian discrete choice experiment design consisting of eight sets of 24 (matched pairwise) choice tasks was developed, with each set providing full identification of the included parameters. Mixed logit models were used to estimate health state preferences with respondents' own health included as an additional predictor. Our results indicate that respondents with impaired health worse than or equal to the health state levels under evaluation have approximately 30% smaller health state decrements. This confirms that reference dependency can be observed in general population samples and affirms the relevance of prospect theory in health state valuations. At the same time, the limited number of respondents with severe health impairments does not appear to bias social tariffs as obtained from general population samples. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Using discrete choice experiments to understand preferences in health care.

PubMed

Pfarr, Christian; Schmid, Andreas; Schneider, Udo

2014-01-01

Whenever processes are reconfigured or new products are designed the needs and preferences of patients and consumers have to be considered. Although at times neglected, this becomes more and more relevant in health care settings: Which modes of health care delivery will be accepted? What are the patients' priorities and what is the willingness to pay? To which degree are patients mobile and for which kind of services are they willing to travel? Preferences, however, are difficult to measure, as they are latent constructs. This becomes even more difficult, when no past choices can be analyzed either as the service or the product is yet to be developed or as in the past there has not been free choice for patients. In such cases, preferences cannot be surveyed directly. Asking individuals openly for their attitudes towards certain services and products, the results are likely biased as individuals are not confronted with budget constraints and trade-offs. For this reason, discrete choice experiments (DCEs) are frequently used to elicit patient preferences. This approach confronts patients with hypothetical scenarios of which only one can be chosen. Over the past few years, this tool to reveal patients' preferences for health care has become very popular in health economics. This contribution aims at introducing the principles of DCEs, highlighting the underlying theory and giving practical guidance for conducting a discrete choice experiment in health economics. Thereby we focus on three major fields of patient demand: designing health insurance, assessing patient utility of new pharmaceuticals and analyzing provider choice. By having a closer look at selected international studies, we discuss the application of this technique for the analysis of the supply and the demand of health care as well as the implications for assessing patient mobility across different health care systems.

The effect of traffic lights and regulatory statements on the choice between complementary and conventional medicines in Australia: results from a discrete choice experiment.

PubMed

Spinks, Jean; Mortimer, Duncan

2015-01-01

It has been suggested that complementary medicines are currently 'under-regulated' in some countries due to their potential for harm as a direct result from side-effects or interactions; from delaying more effective care; or from the economic cost of purchasing an ineffective or inappropriate treatment. The requirement of additional labelling on complementary medicine products has been suggested in Australia and may provide additional information to consumers at the point of purchase. This paper details a unique way of testing the potential effects on consumer behaviour of including either a traffic light logo or regulatory statement on labels. Using a discrete choice experiment, data were collected in 2012 in a sample of 521 Australians with either type 2 diabetes or cardiovascular disease. We find that additional labelling can affect consumer behaviour, but in unpredictable ways. The results of this experiment are informative to further the dialogue concerning possible regulatory mechanisms. Copyright © 2014 Elsevier Ltd. All rights reserved.

Using Blocked Fractional Factorial Designs to Construct Discrete Choice Experiments for Health Care Studies

PubMed Central

Jaynes, Jessica; Wong, Weng Kee; Xu, Hongquan

2016-01-01

Discrete choice experiments (DCEs) are increasingly used for studying and quantifying subjects preferences in a wide variety of health care applications. They provide a rich source of data to assess real-life decision making processes, which involve trade-offs between desirable characteristics pertaining to health and health care, and identification of key attributes affecting health care. The choice of the design for a DCE is critical because it determines which attributes’ effects and their interactions are identifiable. We apply blocked fractional factorial designs to construct DCEs and address some identification issues by utilizing the known structure of blocked fractional factorial designs. Our design techniques can be applied to several situations including DCEs where attributes have different number of levels. We demonstrate our design methodology using two health care studies to evaluate (1) asthma patients’ preferences for symptom-based outcome measures, and (2) patient preference for breast screening services. PMID:26823156

Testing Cessation Messages for Cigarette Package Inserts: Findings from a Best/Worst Discrete Choice Experiment

PubMed Central

Thrasher, James F.; Davis, Rachel E.; Popova, Lucy; Cho, Yoo Jin; Salloum, Ramzi G.; Louviere, Jordan; Hammond, David

2018-01-01

This study assessed smokers’ responses to different smoking cessation topics and imagery for cigarette package inserts. Adult smokers from Canada (n = 1000) participated in three discrete choice experiments (DCEs): DCE 1 assessed five cessation benefit topics and five imagery types; DCE 2 assessed five messages with tips to improve cessation success and five imagery types; DCE 3 assessed four reproductive health benefits of cessation topics and four imagery types. In each DCE, participants evaluated four or five sets of four inserts, selecting the most and least motivating (DCEs 1 & 3) or helpful (DCE 2) for quitting. Linear mixed models regressed choices on insert and smoker characteristics. For DCE 1, the most motivating messages involved novel disease topics and imagery of younger women. For DCE 2, topics of social support, stress reduction and nicotine replacement therapy were selected as most helpful, with no differences by imagery type. For DCE 3, imagery influenced choices more than topic, with imagery of a family or a mom and baby selected as most motivating. Statistically significant interactions for all three experiments indicated that the influence of imagery type on choices depended on the message topic. Messages to promote smoking cessation through cigarette pack inserts should consider specific combinations of message topic and imagery. PMID:29415523

Eliciting preferences for medical devices in South Korea: A discrete choice experiment.

PubMed

Lee, Hye-Jae; Bae, Eun-Young

2017-03-01

This study aims to identify the attributes that contribute to the value of medical devices and quantify the relative importance of them using a discrete choice experiment. Based on a literature review and expert consultation, seven attributes and their levels were identified-severity of disease (2), availability of substitutes (2), improvement in procedure (3), improvement in clinical outcomes (2), increase in survival (2), improvement in quality of life (3), and cost (4). Among 576 hypothetical profiles, optimal choice sets with 20 choices were developed and experts experienced in health technology assessment and reimbursement decision making in South Korea were surveyed. A total of 102 respondents participated in the survey. The results of the random-effect probit model showed that among the seven attributes, six, except for improvement in procedure, had a significant impact on respondents' choices on medical devices. Respondents were willing to pay the highest amount for devices that provided substantial improvements in quality of life, followed by increased survival, improved clinical outcome, treatment without substitutes, and technology for treating severe diseases. The findings of this experiment will inform decision-makers of the relative importance of the criteria and help them in reimbursement decision making of medical devices. Copyright © 2017 Elsevier B.V. All rights reserved.

Women's Preferences for Place of Delivery in Rural Tanzania: A Population-Based Discrete Choice Experiment

PubMed Central

Paczkowski, Magdalena; Mbaruku, Godfrey; de Pinho, Helen; Galea, Sandro

2009-01-01

Objectives. We fielded a population-based discrete choice experiment (DCE) in rural western Tanzania, where only one third of women deliver children in a health facility, to evaluate health-system factors that influence women's delivery decisions. Methods. Women were shown choice cards that described 2 hypothetical health centers by means of 6 attributes (distance, cost, type of provider, attitude of provider, drugs and equipment, free transport). The women were then asked to indicate which of the 2 facilities they would prefer to use for a future delivery. We used a hierarchical Bayes procedure to estimate individual and mean utility parameters. Results. A total of 1203 women completed the DCE. The model showed good predictive validity for actual facility choice. The most important facility attributes were a respectful provider attitude and availability of drugs and medical equipment. Policy simulations suggested that if these attributes were improved at existing facilities, the proportion of women preferring facility delivery would rise from 43% to 88%. Conclusions. In regions in which attended delivery rates are low despite availability of primary care facilities, policy experiments should test the effect of targeted quality improvements on facility use. PMID:19608959

Sample Design for Discrete Choice Analysis of Travel Behavior

DOT National Transportation Integrated Search

1978-07-01

Discrete choice models represent the choices of individuals among alternatives such as modes of travel, auto types and destinations. This paper presents a review of the state-of-the-art in designing samples for discrete choice analysis of traveller b...

Lost in the crowd? Using eye-tracking to investigate the effect of complexity on attribute non-attendance in discrete choice experiments.

PubMed

Spinks, Jean; Mortimer, Duncan

2016-02-03

The provision of additional information is often assumed to improve consumption decisions, allowing consumers to more accurately weigh the costs and benefits of alternatives. However, increasing the complexity of decision problems may prompt changes in information processing. This is particularly relevant for experimental methods such as discrete choice experiments (DCEs) where the researcher can manipulate the complexity of the decision problem. The primary aims of this study are (i) to test whether consumers actually process additional information in an already complex decision problem, and (ii) consider the implications of any such 'complexity-driven' changes in information processing for design and analysis of DCEs. A discrete choice experiment (DCE) is used to simulate a complex decision problem; here, the choice between complementary and conventional medicine for different health conditions. Eye-tracking technology is used to capture the number of times and the duration that a participant looks at any part of a computer screen during completion of DCE choice sets. From this we can analyse what has become known in the DCE literature as 'attribute non-attendance' (ANA). Using data from 32 participants, we model the likelihood of ANA as a function of choice set complexity and respondent characteristics using fixed and random effects models to account for repeated choice set completion. We also model whether participants are consistent with regard to which characteristics (attributes) they consider across choice sets. We find that complexity is the strongest predictor of ANA when other possible influences, such as time pressure, ordering effects, survey specific effects and socio-demographic variables (including proxies for prior experience with the decision problem) are considered. We also find that most participants do not apply a consistent information processing strategy across choice sets. Eye-tracking technology shows promise as a way of obtaining additional information from consumer research, improving DCE design, and informing the design of policy measures. With regards to DCE design, results from the present study suggest that eye-tracking data can identify the point at which adding complexity (and realism) to DCE choice scenarios becomes self-defeating due to unacceptable increases in ANA. Eye-tracking data therefore has clear application in the construction of guidelines for DCE design and during piloting of DCE choice scenarios. With regards to design of policy measures such as labelling requirements for CAM and conventional medicines, the provision of additional information has the potential to make difficult decisions even harder and may not have the desired effect on decision-making.

[What is important for Israeli women who give birth? Estimation of the preference structure using a Discrete Choice Experiment (DCE)].

PubMed

Neuman, Tzahi; Neuman, Einat

2009-10-01

This article aims to estimate the preference structure of attributes of maternity-wards, as expressed by Israeli women who recently gave birth. The estimation is based on data generated by an experiment that simulates actual choices of hospital (Discrete Choice experiment). The sample includes 323 women who gave birth in the year 2003 in three large hospitals in the central part of Israel (The Sheba Medical Center, Tel Hashomer; The Rabin Medical Center, Beilinson Campus in Petah Tikva; and the Meir Medical Center in Kfar Saba). It was found that the ranking of attributes (in a descending order in terms of importance) is: professionalism of the staff, attention of staff towards the patient, transfer of information, and travel time from residence to the hospital. Most women who gave birth did not care about the number of beds in the room at hospitalization (that represents the physical facilities). The technique used in this study is unique and can assist policymakers in allocation of funds, analysis of new policies even before they have been implemented and inclusion of new services.

Determining Preferences Related to HIV Counselling and Testing Services Among High School Learners in KwaZulu-Natal: A Discrete Choice Experiment.

PubMed

Strauss, Michael; George, Gavin L; Rhodes, Bruce D

2018-01-01

A key strategy of the South African national response to HIV is the scale-up of HIV counselling and testing (HCT) in the 15-49 years age group. The integrated school health policy aims to guide the roll out of youth-friendly health services including the provision of HCT in schools. Using a discrete choice experiment to examine preferences regarding the attributes of HCT service packages, this study identifies barriers to and facilitators of HCT among high school learners. Monetary considerations were found to have the strongest effect of any attribute on choice, whilst confidentiality was found to be a primary concern for learners considering HCT. Policy makers and service providers must ensure that confidentiality is maintained, and could consider using monetary incentives as a way of increasing uptake of HCT. Programmes designed to reduce social stigma and improve education and knowledge dissemination around HCT and HIV, are vital in creating demand for HCT and changing attitudes among young people.

Measuring stroke patients' exercise preferences using a discrete choice experiment.

PubMed

Geidl, Wolfgang; Knocke, Katja; Schupp, Wilfried; Pfeifer, Klaus

2018-03-30

Physical activity post stroke improves health, yet physical inactivity is highly prevalent. Tailored exercise programs considering physical activity preferences are a promising approach to promote physical activity. Therefore, this study seeks to measure exercise preferences of stroke survivors. Stroke survivors conducted a discrete choice experiment (DCE). DCE was presented in a face-to-face interview where patients had to choose eight times between two different exercise programs. Exercise programs differed by characteristics, with the six attributes under consideration being social situation, location, type of exercise, intensity, frequency, and duration. Utilities of the exercise attributes were estimated with a logit choice model. Stroke survivors (n=103, mean age: 67, SD=13.0; 60% male) show significant differences in the rated utilities of the exercise attributes (P<0.001). Participants had strong preferences for light and moderate intense physical activity and favored shorter exercise sessions. Stroke survivors have remarkable exercise preferences especially for intensity and duration of exercise. Results contribute to the tailoring of physical activity programs after stroke thereby facilitating maintenance of physical activity.

Calculating Preference Weights for the Labor and Delivery Index: A Discrete Choice Experiment on Women's Birth Experiences.

PubMed

Gärtner, Fania R; de Bekker-Grob, Esther W; Stiggelbout, Anne M; Rijnders, Marlies E; Freeman, Liv M; Middeldorp, Johanna M; Bloemenkamp, Kitty W M; de Miranda, Esteriek; van den Akker-van Marle, M Elske

2015-09-01

The aim of this study was to calculate preference weights for the Labor and Delivery Index (LADY-X) to make it suitable as a utility measure for perinatal care studies. In an online discrete choice experiment, 18 pairs of hypothetical scenarios were presented to respondents, from which they had to choose a preferred option. The scenarios describe the birth experience in terms of the seven LADY-X attributes. A D-efficient discrete choice experiment design with priors based on a small sample (N = 110) was applied. Two samples were gathered, women who had recently given birth and subjects from the general population. Both samples were analyzed separately using a panel mixed logit (MMNL) model. Using the panel mixed multinomial logit (MMNL) model results and accounting for preference heterogeneity, we calculated the average preference weights for LADY-X attribute levels. These were transformed to represent a utility score between 0 and 1, with 0 representing the worst and 1 representing the best birth experience. In total, 1097 women who had recently given birth and 367 subjects from the general population participated. Greater value was placed on differences between bottom and middle attribute levels than on differences between middle and top levels. The attributes that resulted in larger utility increases than the other attributes were "feeling of safety" in the sample of women who had recently given birth and "feeling of safety" and "availability of professionals" in the general population sample. By using the derived preference weights, LADY-X has the potential to be used as a utility measure for perinatal (cost-) effectiveness studies. Copyright © 2015 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Hospital sector choice and support for public hospital care in New Zealand: Results from a labeled discrete choice survey.

PubMed

Brown, Paul; Panattoni, Laura; Cameron, Linda; Knox, Stephanie; Ashton, Toni; Tenbensel, Tim; Windsor, John

2015-09-01

This study uses a discrete choice experiment (DCE) to measure patients' preferences for public and private hospital care in New Zealand. A labeled DCE was administered to 583 members of the general public, with the choice between a public and private hospital for a non-urgent surgery. The results suggest that cost of surgery, waiting times for surgery, option to select a surgeon, convenience, and conditions of the hospital ward are important considerations for patients. The most important determinant of hospital choice was whether it was a public or private hospital, with respondents far more likely to choose a public hospital than a private hospital. The results have implications for government policy toward using private hospitals to clear waiting lists in public hospitals, with these results suggesting the public might not be indifferent to policies that treat private hospitals as substitutes for public hospitals. Copyright © 2015 Elsevier B.V. All rights reserved.

What determines patient preferences for treating low risk basal cell carcinoma when comparing surgery vs imiquimod? A discrete choice experiment survey from the SINS trial.

PubMed

Tinelli, Michela; Ozolins, Mara; Bath-Hextall, Fiona; Williams, Hywel C

2012-10-04

The SINS trial (Controlled Clinical Trials ISRCTN48755084; Eudract No. 2004-004506-24) is a randomised controlled trial evaluating long term success of excisional surgery vs. imiquimod 5% cream for low risk nodular and superficial basal cell carcinoma (BCC). The trial included a discrete choice experiment questionnaire to explore patient preferences of a cream versus surgery for the treatment of their skin cancer. The self-completed questionnaire was administered at baseline to 183 participants, measuring patients' strength of preferences when choosing either alternative 'surgery' or 'imiquimod cream' instead of a fixed 'current situation' option (of surgical excision as standard practice in UK). The treatments were described according to: cost, chance of complete clearance, side effects and appearance. Participants had to choose between various scenarios. Analysis was performed using a mixed logit model, which took into account the impact of previous BCC treatment and sample preference variability. The analysis showed that respondents preferred 'imiquimod cream' to their 'current situation' or 'surgery', regardless of previous experience of BCC symptoms and treatment. Respondents were more likely to be worried about their cosmetic outcomes and side effects they might experience over and above their chance of clearance and cost. Those with no experience of surgery (compared with experience) valued more the choice of 'imiquimod cream' (£1013 vs £781). All treatment characteristics were significant determinants of treatment choice, and there was significant variability in the population preferences for all of them. Patients with BCC valued more 'imiquimod cream' than alternative 'surgery' options, and all treatment characteristics were important for their choice of care. Understanding how people with a BCC value alternative interventions may better inform the development of health care interventions.

Personal health records in the Netherlands: potential user preferences quantified by a discrete choice experiment.

PubMed

Determann, Domino; Lambooij, Mattijs S; Gyrd-Hansen, Dorte; de Bekker-Grob, Esther W; Steyerberg, Ewout W; Heldoorn, Marcel; Pedersen, Line Bjørnskov; de Wit, G Ardine

2017-05-01

To identify groups of potential users based on their preferences for characteristics of personal health records (PHRs) and to estimate potential PHR uptake. We performed a discrete choice experiment, which consisted of 12 choice scenarios, each comprising 2 hypothetical PHR alternatives and an opt-out. The alternatives differed based on 5 characteristics. The survey was administered to Internet panel members of the Dutch Federation of Patients and Consumer Organizations. We used latent class models to analyze the data. A total of 1,443 potential PHR users completed the discrete choice experiment. We identified 3 latent classes: "refusers" (class probability 43%), "eager adopters" (37%), and "reluctant adopters" (20%). The predicted uptake for the reluctant adopters ranged from 4% in the case of a PHR with the worst attribute levels to 68% in the best case. Those with 1 or more chronic diseases were significantly more likely to belong to the eager adopter class. The data storage provider was the most decisive aspect for the eager and reluctant adopters, while cost was most decisive for the refusers. Across all classes, health care providers and independent organizations were the most preferred data storage providers. We identified 3 groups, of which 1 group (more than one-third of potential PHR users) indicated great interest in a PHR irrespective of PHR characteristics. Policymakers who aim to expand the use of PHRs will be most successful when health care providers and health facilities or independent organizations store PHR data while refraining from including market parties. © The Author 2016. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Preferences for breast cancer risk reduction among BRCA1/BRCA2 mutation carriers: a discrete-choice experiment.

PubMed

Liede, Alexander; Mansfield, Carol A; Metcalfe, Kelly A; Price, Melanie A; Snyder, Carrie; Lynch, Henry T; Friedman, Sue; Amelio, Justyna; Posner, Joshua; Narod, Steven A; Lindeman, Geoffrey J; Evans, D Gareth

2017-09-01

Unaffected women who carry BRCA1 or BRCA2 mutations face difficult choices about reducing their breast cancer risk. Understanding their treatment preferences could help us improve patient counseling and inform drug trials. The objective was to explore preferences for various risk-reducing options among women with germline BRCA1/2 mutations using a discrete-choice experiment survey and to compare expressed preferences with actual behaviors. A discrete-choice experiment survey was designed wherein women choose between hypothetical treatments to reduce breast cancer risk. The hypothetical treatments were characterized by the extent of breast cancer risk reduction, treatment duration, impact on fertility, hormone levels, risk of uterine cancer, and ease and mode of administration. Data were analyzed using a random-parameters logit model. Women were also asked to express their preference between surgical and chemoprevention options and to report on their actual risk-reduction actions. Women aged 25-55 years with germline BRCA1/2 mutations who were unaffected with breast or ovarian cancer were recruited through research registries at five clinics and a patient advocacy group. Between January 2015 and March 2016, 622 women completed the survey. Breast cancer risk reduction was the most important consideration expressed, followed by maintaining fertility. Among the subset of women who wished to have children in future, the ability to maintain fertility was the most important factor, followed by the extent of risk reduction. Many more women said they would take a chemoprevention drug than had actually taken chemoprevention. Women with BRCA1/2 mutations indicated strong preferences for breast cancer risk reduction and maintaining fertility. The expressed desire to have a safe chemoprevention drug available to them was not met by current chemoprevention options.

Cultural Attitudes, Parental Aspirations, and Socioeconomic Influence on Post-Primary School Selection in Northern Ireland

ERIC Educational Resources Information Center

Kelleher, Luke; Smyth, Austin; McEldowney, Malachy

2016-01-01

This research considers implications of planned reform of the education system in Northern Ireland for school choice and travel behavior. The school system is currently segregated on the basis of religion and academic ability at age 11. Discrete Choice Models based on a Stated Preference experiment included in a program of parental surveys yielded…

The effect of presenting information about invasive follow-up testing on individuals' noninvasive colorectal cancer screening participation decision: results from a discrete choice experiment.

PubMed

Benning, Tim M; Dellaert, Benedict G C; Severens, Johan L; Dirksen, Carmen D

2014-07-01

Many national colorectal cancer screening campaigns have a similar structure. First, individuals are invited to take a noninvasive screening test, and, second, in the case of a positive screening test result, they are advised to undergo a more invasive follow-up test. The objective of this study was to investigate how much individuals' participation decision in noninvasive screening is affected by the presence or absence of detailed information about invasive follow-up testing and how this effect varies over screening tests. We used a labeled discrete choice experiment of three noninvasive colorectal cancer screening types with two versions that did or did not present respondents with detailed information about the possible invasive follow-up test (i.e., colonoscopy) and its procedure. We used data from 631 Dutch respondents aged 55 to 75 years. Each respondent received only one of the two versions (N = 310 for the invasive follow-up test information specification version, and N = 321 for the no-information specification version). Mixed logit model results show that detailed information about the invasive follow-up test negatively affects screening participation decisions. This effect can be explained mainly by a decrease in choice shares for the most preferred screening test (a combined stool and blood sample test). Choice share simulations based on the discrete choice experiment indicated that presenting invasive follow-up test information decreases screening participation by 4.79%. Detailed information about the invasive follow-up test has a negative effect on individuals' screening participation decisions in noninvasive colorectal cancer screening campaigns. This result poses new challenges for policymakers who aim not only to increase uptake but also to provide full disclosure to potential screening participants. Copyright © 2014 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Patient preferences for osteoporosis in Spain: a discrete choice experiment.

PubMed

Darbà, J; Restovic, G; Kaskens, L; Balbona, M A; Carbonell, A; Cavero, P; Jordana, M; Prieto, C; Molina, A; Padró, I

2011-06-01

In Spain, various treatments are available to prevent osteoporotic fractures. A discrete choice experiment (DCE) was used to investigate the importance of different treatment aspects and its influence on patients' preferences. All attributes included as type and place of drug administration as well as costs showed to be significant predictors of choice. Spanish osteoporosis patients have well-defined preferences and accept trade-offs among attributes. This study was designed to identify patient preferences for different aspects of osteoporosis treatments in Spain. Main attributes of severe osteoporosis treatments were determined by literature review and consultations with nurses. The discrete choice experiment included three attributes: type of drug administration, place of administration, plus a cost attribute in order to estimate willingness to pay for improvements in attribute levels. A pilot study with 50 patients was performed to identify the areas of misunderstanding. One hundred sixty-six patients with a diagnosis of osteoporosis and severe osteoporosis were presented with pairs of hypothetical treatment profiles with different type of administration levels, places of administration and costs. Questions to collect socio-demographic and disease-related treatment data were also included. Data were analysed using a random effects probit model. All attributes had the expected polarity and were significant predictors of choice. Patients were willing to pay 183 euro/month to have a subcutaneous injection once per day rather than an intravenous injection once per year. Patients with osteoporosis were willing to pay 121 euro/month to have medical support when administering the drug treatment at home rather than being admitted several hours to a hospital for drug administration. Spanish osteoporosis patients have well-defined preferences among treatment attributes and are willing to accept trade-offs among attributes. Participants indicated that they are willing to accept self medication with medical support rather than being hospitalised for several hours. The perspective of the patients should be taken into account when making treatment decisions.

Modeling the mental health service utilization decisions of university undergraduates: A discrete choice conjoint experiment.

PubMed

Cunningham, Charles E; Zipursky, Robert B; Christensen, Bruce K; Bieling, Peter J; Madsen, Victoria; Rimas, Heather; Mielko, Stephanie; Wilson, Fiona; Furimsky, Ivana; Jeffs, Lisa; Munn, Catharine

2017-01-01

We modeled design factors influencing the intent to use a university mental health service. Between November 2012 and October 2014, 909 undergraduates participated. Using a discrete choice experiment, participants chose between hypothetical campus mental health services. Latent class analysis identified three segments. A Psychological/Psychiatric Service segment (45.5%) was most likely to contact campus health services delivered by psychologists or psychiatrists. An Alternative Service segment (39.3%) preferred to talk to peer-counselors who had experienced mental health problems. A Hesitant segment (15.2%) reported greater distress but seemed less intent on seeking help. They preferred services delivered by psychologists or psychiatrists. Simulations predicted that, rather than waiting for standard counseling, the Alternative Service segment would prefer immediate access to E-Mental health. The Usual Care and Hesitant segments would wait 6 months for standard counseling. E-Mental Health options could engage students who may not wait for standard services.

Specification of the utility function in discrete choice experiments.

PubMed

van der Pol, Marjon; Currie, Gillian; Kromm, Seija; Ryan, Mandy

2014-03-01

The specification of the utility function has received limited attention within the discrete choice experiment (DCE) literature. This lack of investigation is surprising given that evidence from the contingent valuation literature suggests that welfare estimates are sensitive to different specifications of the utility function. This study investigates the effect of different specifications of the utility function on results within a DCE. The DCE elicited the public's preferences for waiting time for hip and knee replacement and estimated willingness to wait (WTW). The results showed that the WTW for the different patient profiles varied considerably across the three different specifications of the utility function. Assuming a linear utility function led to much higher estimates of marginal rates of substitution (WTWs) than with nonlinear specifications. The goodness-of-fit measures indicated that nonlinear specifications were superior. Copyright © 2014 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Pigeons' Choices between Fixed-Interval and Random-Interval Schedules: Utility of Variability?

ERIC Educational Resources Information Center

Andrzejewski, Matthew E.; Cardinal, Claudia D.; Field, Douglas P.; Flannery, Barbara A.; Johnson, Michael; Bailey, Kathleen; Hineline, Philip N.

2005-01-01

Pigeons' choosing between fixed-interval and random-interval schedules of reinforcement was investigated in three experiments using a discrete-trial procedure. In all three experiments, the random-interval schedule was generated by sampling a probability distribution at an interval (and in multiples of the interval) equal to that of the…

Breast Cancer Knowledge, Behaviors, and Preferences in Malawi: Implications for Early Detection Interventions From a Discrete Choice Experiment.

PubMed

Kohler, Racquel E; Gopal, Satish; Lee, Clara N; Weiner, Bryan J; Reeve, Bryce B; Wheeler, Stephanie B

2017-10-01

Breast cancer is the most common female cancer in Africa and leading cause of death resulting from cancer; however, many countries lack early detection services. In Malawi, women are frequently diagnosed with large tumors after long symptomatic periods. Little is known about local cancer knowledge. We administered a cross-sectional survey with a discrete choice experiment to a random sample in urban and rural areas of Lilongwe district. Bivariable and multivariable analyses determined factors associated with knowledge. Preference utilities for early detection interventions were estimated using a hierarchical Bayesian model in Sawtooth software. Of 213 women recruited, fewer than half were aware of breast cancer. In multivariable analysis, electricity at home and knowing someone with cancer increased the odds of awareness. Women were more knowledgeable about symptoms than treatment or risk factors; more than 60% erroneously believed local misconceptions. Seventeen percent were aware of breast self-examination, and 20% were aware of clinical breast examination (CBE); few reported either behavior. Common barriers included not knowing where to access CBE and transportation difficulties. Discrete choice experiment results indicated the detection strategy (breast health awareness, CBE, or both) was the most important attribute of an intervention, followed by the encounter setting and travel time. Addressing misconceptions in health messages and engaging survivors to promote early detection may help improve breast cancer knowledge in Malawi. Program designs accounting for women's preferences should provide breast health education and CBEs in convenient settings to address transportation barriers, particularly for women with low socioeconomic position.

Measuring Preferences for a Diabetes Pay-for-Performance for Patient (P4P4P) Program using a Discrete Choice Experiment.

PubMed

Chen, Tsung-Tai; Tung, Tao-Hsin; Hsueh, Ya-Seng Arthur; Tsai, Ming-Han; Liang, Hsiu-Mei; Li, Kay-Lun; Chung, Kuo-Piao; Tang, Chao-Hsiun

2015-07-01

To elicit a patient's willingness to participate in a diabetes pay-for-performance for patient (P4P4P) program using a discrete choice experiment method. The survey was conducted in March 2013. Our sample was drawn from patients with diabetes at five hospitals in Taiwan (International Classification of Diseases, Ninth Revision, Clinical Modification code 250). The sample size was 838 patients. The discrete choice experiment questionnaire included the attributes monthly cash rewards, exercise time, diet control, and program duration. We estimated a bivariate probit model to derive willingness-to-accept levels after accounting for the characteristics (e.g., severity and comorbidity) of patients with diabetes. The preferred program was a 3-year program involving 30 minutes of exercise per day and flexible diet control. Offering an incentive of approximately US $67 in cash per month appears to increase the likelihood that patients with diabetes will participate in the preferred P4P4P program by approximately 50%. Patients with more disadvantageous characteristics (e.g., elderly, low income, greater comorbidity, and severity) could have less to gain from participating in the program and thus require a higher monetary incentive to compensate for the disutility caused by participating in the program's activities. Our result demonstrates that a modest financial incentive could increase the likelihood of program participation after accounting for the attributes of the P4P4P program and patients' characteristics. Copyright © 2015 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Qualitative Development of a Discrete Choice Experiment for Physical Activity Interventions to Improve Knee Osteoarthritis.

PubMed

Pinto, Daniel; Danilovich, Margaret K; Hansen, Paul; Finn, Daniel J; Chang, Rowland W; Holl, Jane L; Heinemann, Allen W; Bockenholt, Ulf

2017-06-01

To describe the qualitative process used to develop attributes and attribute levels for inclusion in a discrete choice experiments (DCE) for older adult physical activity interventions. Five focus groups (n=41) were conducted, grounded in the Health Action Process Approach framework. Discussion emphasized identification and prioritization attributes for a DCE on physical activity. Semi-structured interviews (n=6) investigated attribute levels and lay-language for the DCE. A focus group with physical activity researchers and health care providers was the final stakeholder group used to establish a comprehensive approach for the generation of attributes and levels. A DCE pilot test (n=8) was then conducted with individuals of the target patient population. All transcripts were analyzed using a constant comparative approach. General community and university-based research setting. Volunteers (N=55) aged >45 years with knee pain, aches, or stiffness for at least 1 month over the previous 12 months. Not applicable. Interview guides, attributes, attribute levels, and discrete choice experiment. The most influential identified attributes for physical activity were time, effort, cost, convenience, enjoyment, and health benefits. Each attribute had 3 levels that were understandable in the pilot test of the DCE. The identification of 6 physical activity attributes that are most salient to adults with knee osteoarthritis resulted from a systematic qualitative process, including attribute-ranking exercises. A DCE will provide insight into the relative importance of these attributes for participating in physical activity, which can guide intervention development. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Breast Cancer Knowledge, Behaviors, and Preferences in Malawi: Implications for Early Detection Interventions From a Discrete Choice Experiment

PubMed Central

Gopal, Satish; Lee, Clara N.; Weiner, Bryan J.; Reeve, Bryce B.; Wheeler, Stephanie B.

2017-01-01

Purpose Breast cancer is the most common female cancer in Africa and leading cause of death resulting from cancer; however, many countries lack early detection services. In Malawi, women are frequently diagnosed with large tumors after long symptomatic periods. Little is known about local cancer knowledge. Methods We administered a cross-sectional survey with a discrete choice experiment to a random sample in urban and rural areas of Lilongwe district. Bivariable and multivariable analyses determined factors associated with knowledge. Preference utilities for early detection interventions were estimated using a hierarchical Bayesian model in Sawtooth software. Results Of 213 women recruited, fewer than half were aware of breast cancer. In multivariable analysis, electricity at home and knowing someone with cancer increased the odds of awareness. Women were more knowledgeable about symptoms than treatment or risk factors; more than 60% erroneously believed local misconceptions. Seventeen percent were aware of breast self-examination, and 20% were aware of clinical breast examination (CBE); few reported either behavior. Common barriers included not knowing where to access CBE and transportation difficulties. Discrete choice experiment results indicated the detection strategy (breast health awareness, CBE, or both) was the most important attribute of an intervention, followed by the encounter setting and travel time. Conclusion Addressing misconceptions in health messages and engaging survivors to promote early detection may help improve breast cancer knowledge in Malawi. Program designs accounting for women’s preferences should provide breast health education and CBEs in convenient settings to address transportation barriers, particularly for women with low socioeconomic position. PMID:29094086

Perceived Risks Contra Benefits of Using Biosimilar Drugs in Ulcerative Colitis: Discrete Choice Experiment among Gastroenterologists.

PubMed

Baji, Petra; Gulácsi, László; Golovics, Petra A; Lovász, Barbara D; Péntek, Márta; Brodszky, Valentin; Rencz, Fanni; Lakatos, Péter L

2016-09-01

In middle-income countries, access to biological therapy is limited in ulcerative colitis in terms of the number of patients and the length of therapy. Because of their cost advantages, biosimilars have the potential to improve access to therapy, but physicians have concerns toward their use because of the lack of evidence from randomized clinical trials. To explore the preferences of gastroenterologists for biosimilar drugs in ulcerative colitis as well as to compare our results with results of previous studies on gastroenterologists' preferences toward biosimilars. A discrete choice experiment was carried out involving 51 Hungarian gastroenterologists treating patients with inflammatory bowel disease in May 2014 with the following attributes: type of treatment (biosimilar/originator), severity of disease, availability of continuous medicine supply, and the stopping rule (whether the treatment is covered after 12 months). A conditional logit model was used to estimate the probabilities of choosing a given profile. According to the results, the stopping rule was the most important attribute. The type of treatment mattered only for patients already on biologicals. The probabilities of choosing the biosimilar option with all the benefits offered in the discrete choice experiment over the originator option under the present reimbursement conditions are 85% for new patients and 63% for patients already treated. Most gastroenterologists have concerns about using biosimilars. They, however, are willing to consider the use of biosimilars if they could reallocate the potential savings to provide their patients better access to biological treatment. Copyright © 2016 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Preferences for a third-trimester ultrasound scan in a low-risk obstetric population: a discrete choice experiment.

PubMed

Lynn, Fiona A; Crealey, Grainne E; Alderdice, Fiona A; McElnay, James C

2015-10-01

Establish maternal preferences for a third-trimester ultrasound scan in a healthy, low-risk pregnant population. Cross-sectional study incorporating a discrete choice experiment. A large, urban maternity hospital in Northern Ireland. One hundred and forty-six women in their second trimester of pregnancy. A discrete choice experiment was designed to elicit preferences for four attributes of a third-trimester ultrasound scan: health-care professional conducting the scan, detection rate for abnormal foetal growth, provision of non-medical information, cost. Additional data collected included age, marital status, socio-economic status, obstetric history, pregnancy-specific stress levels, perceived health and whether pregnancy was planned. Analysis was undertaken using a mixed logit model with interaction effects. Women's preferences for, and trade-offs between, the attributes of a hypothetical scan and indirect willingness-to-pay estimates. Women had significant positive preference for higher rate of detection, lower cost and provision of non-medical information, with no significant value placed on scan operator. Interaction effects revealed subgroups that valued the scan most: women experiencing their first pregnancy, women reporting higher levels of stress, an adverse obstetric history and older women. Women were able to trade on aspects of care and place relative importance on clinical, non-clinical outcomes and processes of service delivery, thus highlighting the potential of using health utilities in the development of services from a clinical, economic and social perspective. Specifically, maternal preferences exhibited provide valuable information for designing a randomized trial of effectiveness and insight for clinical and policy decision makers to inform woman-centred care. © 2013 Blackwell Publishing Ltd.

Random walkers with extreme value memory: modelling the peak-end rule

NASA Astrophysics Data System (ADS)

Harris, Rosemary J.

2015-05-01

Motivated by the psychological literature on the ‘peak-end rule’ for remembered experience, we perform an analysis within a random walk framework of a discrete choice model where agents’ future choices depend on the peak memory of their past experiences. In particular, we use this approach to investigate whether increased noise/disruption always leads to more switching between decisions. Here extreme value theory illuminates different classes of dynamics indicating that the long-time behaviour is dependent on the scale used for reflection; this could have implications, for example, in questionnaire design.

Defining value through quantity and quality-Chimpanzees (Pan troglodytes) undervalue food quantities when items are broken.

PubMed

Parrish, Audrey E; Evans, Theodore A; Beran, Michael J

2015-02-01

Decision-making largely is influenced by the relative value of choice options, and the value of such options can be determined by a combination of different factors (e.g., the quantity, size, or quality of a stimulus). In this study, we examined the competing influences of quantity (i.e., the number of food items in a set) and quality (i.e., the original state of a food item) of choice items on chimpanzees' food preferences in a two-option natural choice paradigm. In Experiment 1, chimpanzees chose between sets of food items that were either entirely whole or included items that were broken into pieces before being shown to the chimpanzees. Chimpanzees exhibited a bias for whole food items even when such choice options consisted of a smaller overall quantity of food than the sets containing broken items. In Experiment 2, chimpanzees chose between sets of entirely whole food items and sets of initially whole items that were subsequently broken in view of the chimpanzees just before choice time. Chimpanzees continued to exhibit a bias for sets of whole items. In Experiment 3, chimpanzees chose between sets of new food items that were initially discrete but were subsequently transformed into a larger cohesive unit. Here, chimpanzees were biased to choose the discrete sets that retained their original qualitative state rather than toward the cohesive or clumped sets. These results demonstrate that beyond a food set's quantity (i.e., the value dimension that accounts for maximization in terms of caloric intake), other seemingly non-relevant features (i.e., quality in terms of a set's original state) affect how chimpanzees assign value to their choice options. Copyright © 2014 Elsevier B.V. All rights reserved.

Simulation study to determine the impact of different design features on design efficiency in discrete choice experiments

PubMed Central

Vanniyasingam, Thuva; Cunningham, Charles E; Foster, Gary; Thabane, Lehana

2016-01-01

Objectives Discrete choice experiments (DCEs) are routinely used to elicit patient preferences to improve health outcomes and healthcare services. While many fractional factorial designs can be created, some are more statistically optimal than others. The objective of this simulation study was to investigate how varying the number of (1) attributes, (2) levels within attributes, (3) alternatives and (4) choice tasks per survey will improve or compromise the statistical efficiency of an experimental design. Design and methods A total of 3204 DCE designs were created to assess how relative design efficiency (d-efficiency) is influenced by varying the number of choice tasks (2–20), alternatives (2–5), attributes (2–20) and attribute levels (2–5) of a design. Choice tasks were created by randomly allocating attribute and attribute level combinations into alternatives. Outcome Relative d-efficiency was used to measure the optimality of each DCE design. Results DCE design complexity influenced statistical efficiency. Across all designs, relative d-efficiency decreased as the number of attributes and attribute levels increased. It increased for designs with more alternatives. Lastly, relative d-efficiency converges as the number of choice tasks increases, where convergence may not be at 100% statistical optimality. Conclusions Achieving 100% d-efficiency is heavily dependent on the number of attributes, attribute levels, choice tasks and alternatives. Further exploration of overlaps and block sizes are needed. This study's results are widely applicable for researchers interested in creating optimal DCE designs to elicit individual preferences on health services, programmes, policies and products. PMID:27436671

Factors influencing job preferences of health workers providing obstetric care: results from discrete choice experiments in Malawi, Mozambique and Tanzania.

PubMed

McAuliffe, Eilish; Galligan, Marie; Revill, Paul; Kamwendo, Francis; Sidat, Mohsin; Masanja, Honorati; de Pinho, Helen; Araujo, Edson

2016-12-20

Task shifting from established health professionals to mid-level providers (MLPs) (professionals who undergo shorter training in specific procedures) is one key strategy for reducing maternal and neonatal deaths. This has resulted in a growth in cadre types providing obstetric care in low and middle-income countries. Little is known about the relative importance of the different factors in determining motivation and retention amongst these cadres. This paper presents findings from large sample (1972 respondents) discrete choice experiments to examine the employment preferences of obstetric care workers across three east African countries. The strongest predictors of job choice were access to continuing professional development and the presence of functioning human resources management (transparent, accountable and consistent systems for staff support, supervision and appraisal). Consistent with similar works we find pay and allowances significantly positively related to utility, but financial rewards are not as fundamental a factor underlying employment preferences as many may have previously believed. Location (urban vs rural) had the smallest average effect on utility for job choice in all three countries. These findings are important in the context where efforts to address the human resources crisis have focused primarily on increasing salaries and incentives, as well as providing allowances to work in rural areas.

Improving the quality of discrete-choice experiments in health: how can we assess validity and reliability?

PubMed

Janssen, Ellen M; Marshall, Deborah A; Hauber, A Brett; Bridges, John F P

2017-12-01

The recent endorsement of discrete-choice experiments (DCEs) and other stated-preference methods by regulatory and health technology assessment (HTA) agencies has placed a greater focus on demonstrating the validity and reliability of preference results. Areas covered: We present a practical overview of tests of validity and reliability that have been applied in the health DCE literature and explore other study qualities of DCEs. From the published literature, we identify a variety of methods to assess the validity and reliability of DCEs. We conceptualize these methods to create a conceptual model with four domains: measurement validity, measurement reliability, choice validity, and choice reliability. Each domain consists of three categories that can be assessed using one to four procedures (for a total of 24 tests). We present how these tests have been applied in the literature and direct readers to applications of these tests in the health DCE literature. Based on a stakeholder engagement exercise, we consider the importance of study characteristics beyond traditional concepts of validity and reliability. Expert commentary: We discuss study design considerations to assess the validity and reliability of a DCE, consider limitations to the current application of tests, and discuss future work to consider the quality of DCEs in healthcare.

Deleting 'irrational' responses from discrete choice experiments: a case of investigating or imposing preferences?

PubMed

Lancsar, Emily; Louviere, Jordan

2006-08-01

Investigation of the 'rationality' of responses to discrete choice experiments (DCEs) has been a theme of research in health economics. Responses have been deleted from DCEs where they have been deemed by researchers to (a) be 'irrational', defined by such studies as failing tests for non-satiation, or (b) represent lexicographic preferences. This paper outlines a number of reasons why deleting responses from DCEs may be inappropriate after first reviewing the theory underpinning rationality, highlighting that the importance placed on rationality depends on the approach to consumer theory to which one ascribes. The aim of this paper is not to suggest that all preferences elicited via DCEs are rational. Instead, it is to suggest a number of reasons why it may not be the case that all preferences labelled as 'irrational' are indeed so. Hence, deleting responses may result in the removal of valid preferences; induce sample selection bias; and reduce the statistical efficiency and power of the estimated choice models. Further, evidence suggests random utility theory may be able to cope with such preferences. Finally, we discuss a number of implications for the design, implementation and interpretation of DCEs and recommend caution regarding the deletion of preferences from stated preference experiments. Copyright 2006 John Wiley & Sons, Ltd.

Choice of electricity provider in California after deregulation

NASA Astrophysics Data System (ADS)

Keanini, Rasa Ilze

Surveys often ask consumers how much they are willing to pay for certain goods and services, without requiring the consumer to actually pay for the good or service. Such surveys, termed stated preference studies, find that consumers value renewable electricity. This result is in contrast to actual experiences in recently deregulated electricity markets in several states, including California. When given the opportunity to choose in California, only one to two percent of the population opted for renewable electricity products. This dissertation used data from residential customers who chose an alternative electricity product in California's deregulated electricity market to determine the value placed on the renewable attribute of electricity products. This dissertation begins by taking a historical look at the electricity market of the nation and specifically California. From 1998 through 2001, California's electricity market was deregulated to include retail competition. This dissertation used data from electric service providers to reveal the factors influencing residential customer's choice of electricity product. Discrete choice models were used to determine the factors influencing electricity product choice. The results indicated that both price and renewable content had an effect on choice of product. Additionally, a more complicated model jointly estimating the discrete choice of electricity product with the continuous choice of electricity consumption (kWh) was specified and estimated.

Box-Cox Mixed Logit Model for Travel Behavior Analysis

NASA Astrophysics Data System (ADS)

Orro, Alfonso; Novales, Margarita; Benitez, Francisco G.

2010-09-01

To represent the behavior of travelers when they are deciding how they are going to get to their destination, discrete choice models, based on the random utility theory, have become one of the most widely used tools. The field in which these models were developed was halfway between econometrics and transport engineering, although the latter now constitutes one of their principal areas of application. In the transport field, they have mainly been applied to mode choice, but also to the selection of destination, route, and other important decisions such as the vehicle ownership. In usual practice, the most frequently employed discrete choice models implement a fixed coefficient utility function that is linear in the parameters. The principal aim of this paper is to present the viability of specifying utility functions with random coefficients that are nonlinear in the parameters, in applications of discrete choice models to transport. Nonlinear specifications in the parameters were present in discrete choice theory at its outset, although they have seldom been used in practice until recently. The specification of random coefficients, however, began with the probit and the hedonic models in the 1970s, and, after a period of apparent little practical interest, has burgeoned into a field of intense activity in recent years with the new generation of mixed logit models. In this communication, we present a Box-Cox mixed logit model, original of the authors. It includes the estimation of the Box-Cox exponents in addition to the parameters of the random coefficients distribution. Probability of choose an alternative is an integral that will be calculated by simulation. The estimation of the model is carried out by maximizing the simulated log-likelihood of a sample of observed individual choices between alternatives. The differences between the predictions yielded by models that are inconsistent with real behavior have been studied with simulation experiments.

Obligatory Effort [Hishtadlut] as an Explanatory Model: A Critique of Reproductive Choice and Control.

PubMed

Teman, Elly; Ivry, Tsipy; Goren, Heela

2016-06-01

Studies on reproductive technologies often examine women's reproductive lives in terms of choice and control. Drawing on 48 accounts of procreative experiences of religiously devout Jewish women in Israel and the US, we examine their attitudes, understandings and experiences of pregnancy, reproductive technologies and prenatal testing. We suggest that the concept of hishtadlut-"obligatory effort"-works as an explanatory model that organizes Haredi women's reproductive careers and their negotiations of reproductive technologies. As an elastic category with negotiable and dynamic boundaries, hishtadlut gives ultra-orthodox Jewish women room for effort without the assumption of control; it allows them to exercise discretion in relation to medical issues without framing their efforts in terms of individual choice. Haredi women hold themselves responsible for making their obligatory effort and not for pregnancy outcomes. We suggest that an alternative paradigm to autonomous choice and control emerges from cosmological orders where reproductive duties constitute "obligatory choices."

Choice-Based Conjoint Analysis: Classification vs. Discrete Choice Models

NASA Astrophysics Data System (ADS)

Giesen, Joachim; Mueller, Klaus; Taneva, Bilyana; Zolliker, Peter

Conjoint analysis is a family of techniques that originated in psychology and later became popular in market research. The main objective of conjoint analysis is to measure an individual's or a population's preferences on a class of options that can be described by parameters and their levels. We consider preference data obtained in choice-based conjoint analysis studies, where one observes test persons' choices on small subsets of the options. There are many ways to analyze choice-based conjoint analysis data. Here we discuss the intuition behind a classification based approach, and compare this approach to one based on statistical assumptions (discrete choice models) and to a regression approach. Our comparison on real and synthetic data indicates that the classification approach outperforms the discrete choice models.

Eliciting population preferences for mass colorectal cancer screening organization.

PubMed

Nayaradou, Maximilien; Berchi, Célia; Dejardin, Olivier; Launoy, Guy

2010-01-01

The implementation of mass colorectal cancer (CRC) screening is a public health priority. Population participation is fundamental for the success of CRC screening as for any cancer screening program. The preferences of the population may influence their likelihood of participation. The authors sought to elicit population preferences for CRC screening test characteristics to improve the design of CRC screening campaigns. A discrete choice experiment was used. Questionnaires were compiled with a set of pairs of hypothetical CRC screening scenarios. The survey was conducted by mail from June 2006 to October 2006 on a representative sample of 2000 inhabitants, aged 50 to 74 years from the northwest of France, who were randomly selected from electoral lists. Questionnaires were sent to 2000 individuals, each of whom made 3 or 4 discrete choices between hypothetical tests that differed in 7 attributes: how screening is offered, process, sensitivity, rate of unnecessary colonoscopy, expected mortality reduction, method of screening test result transmission, and cost. Complete responses were received from 656 individuals (32.8%). The attributes that influenced population preferences included expected mortality reduction, sensitivity, cost, and process. Participants from high social classes were particularly influenced by sensitivity. The results demonstrate that the discrete choice experiment provides information on patient preferences for CRC screening: improving screening program effectiveness, for instance, by improving test sensitivity (the most valued attribute) would increase satisfaction among the general population with regard to CRC screening programs. Additional studies are required to study how patient preferences actually affect adherence to regular screening programs.

A discrete-choice experiment to determine patient preferences for injectable multiple sclerosis treatments in Germany.

PubMed

Poulos, Christine; Kinter, Elizabeth; Yang, Jui-Chen; Bridges, John F P; Posner, Joshua; Gleißner, Erika; Mühlbacher, Axel; Kieseier, Bernd

2016-03-01

The aim of this study was to assess the relative importance of features of a hypothetical injectable disease-modifying treatment for patients with multiple sclerosis using a discrete-choice experiment. German residents at least 18 years of age with a self-reported physician diagnosis of multiple sclerosis completed a 25-30 minute online discrete-choice experiment. Patients were asked to choose one of two hypothetical injectable treatments for multiple sclerosis, defined by different levels of six attributes (disability progression, the number of relapses in the next 4 years, injection time, frequency of injections, presence of flu-like symptoms, and presence of injection-site reactions). The data were analyzed using a random-parameters logit model. Of 202 adults who completed the survey, results from 189 were used in the analysis. Approximately 50% of all patients reported a diagnosis of relapsing-remitting multiple sclerosis, and 31% reported secondary progressive multiple sclerosis. Approximately 71% of patients had current or prior experience with injectable multiple sclerosis medication. Approximately 53% had experienced flu-like symptoms caused by their medication, and 47% had experienced mild injection-site reactions. At least one significant difference was seen between levels in all attributes, except injection time. The greatest change in relative importance between levels of an attribute was years until symptoms get worse from 1 to 4 years. The magnitude of this difference was about twice that of relapses in the next 4 years, frequency of injections, and flu-like symptoms. Most attributes examined in this experiment had an influence on patient preference. Patients placed a significant value on improvements in the frequency of dosing and disability progression. Results suggest that changes in injection frequency can be as important as changes in efficacy and safety attributes. Understanding which attributes of injectable therapies influence patient preference could potentially improve outcomes and adherence in patients with multiple sclerosis.

Women's and healthcare professionals' preferences for prenatal testing: a discrete choice experiment.

PubMed

Beulen, Lean; Grutters, Janneke P C; Faas, Brigitte H W; Feenstra, Ilse; Groenewoud, Hans; van Vugt, John M G; Bekker, Mireille N

2015-06-01

This study evaluates pregnant women's and healthcare professionals' preferences regarding specific prenatal screening and diagnostic test characteristics. A discrete choice experiment was developed to assess preferences for prenatal tests that differed in seven attributes: minimal gestational age, time to test results, level of information, detection rate, false positive rate, miscarriage risk and costs. The questionnaire was completed by 596 (70.2%) pregnant women and 297 (51.7%) healthcare professionals, of whom 507 (85.1%) and 283 (95.3%), respectively, were included in further analyses as their choice behavior indicated prenatal testing was an option to them. Comparison of results showed differences in relative importance attached to attributes, further reflected by differences in willingness to trade between attributes. Pregnant women are willing to accept a less accurate test to obtain more information on fetal chromosomal status or to exclude the risk of procedure-related miscarriage. Healthcare professionals consider level of information and miscarriage risk to be most important as well but put more emphasis on timing and accuracy. Pregnant women and healthcare professionals differ significantly in their preferences regarding prenatal test characteristics. Healthcare professionals should take these differences into consideration when counseling pregnant women on prenatal testing. © 2015 John Wiley & Sons, Ltd.

Factors affecting retention of allied health professionals working with people with disability in rural New South Wales, Australia: discrete choice experiment questionnaire development.

PubMed

Gallego, Gisselle; Dew, Angela; Bulkeley, Kim; Veitch, Craig; Lincoln, Michelle; Bundy, Anita; Brentnall, Jennie

2015-04-21

This paper describes the development of a discrete choice experiment (DCE) questionnaire to identify the factors (attributes) that allied health professionals (AHPs) working with people with disability identify as important to encouraging them to remain practising in rural areas. Focus groups and semi-structured interviews were conducted with 97 purposively selected service providers working with people with disability in rural New South Wales, Australia. Focus groups and interviews were digitally recorded, transcribed, and analysed using a modified grounded theory approach involving thematic analysis and constant comparison. Six attributes that may influence AHPs working with people with disability in rural areas to continue to do so were inductively identified: travel arrangements, work flexibility, professional support, professional development, remuneration, and autonomy of practice. The qualitative research information was combined with a policy review to define these retention factors and ensure that they are amenable to policy changes. The use of various qualitative research methods allowed the development of a policy-relevant DCE questionnaire that was grounded in the experience of the target population (AHPs).

Women's Benefits and Harms Trade-Offs in Breast Cancer Screening: Results from a Discrete-Choice Experiment.

PubMed

Sicsic, Jonathan; Pelletier-Fleury, Nathalie; Moumjid, Nora

2018-01-01

Over the past decade, the benefits and harms balance of breast cancer (BC) screening has been widely debated. To elicit women's trade-offs between the benefits and harms of BC screening and to analyze the main determinants of these trade-offs. A discrete-choice experiment with seven attributes depicting BC screening programs including varying levels of BC mortality, overdiagnosis, and false-positive result was used. Eight hundred twelve women aged 40 to 74 years with no personal history of BC recruited by a survey institute and representative of the French general population (age, socioeconomic level, and geographical location) completed the discrete-choice experiment. Preference heterogeneity was investigated using generalized multinomial logit models from which individual trade-offs were derived, and their main determinants were assessed using generalized linear models. Screening acceptance rates under various benefits and harms ratios were simulated on the basis of the distribution of individual preferences. The women would be willing to accept on average 14.1 overdiagnosis cases (median = 9.6) and 47.8 false-positive results (median = 27.2) to avoid one BC-related death. After accounting for preference heterogeneity, less than 50% of women would be willing to accept 10 overdiagnosis cases for one BC-related death avoided. Screening acceptance rates were higher among women with higher socioeconomic level and lower among women with poor health. Women are sensitive to both the benefits and the harms of BC screening and their preferences are highly heterogeneous. Our study provides useful results for public health authorities and clinicians willing to improve their recommendations of BC screening on the basis of women's preferences. Copyright © 2018 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

German Value Set for the EQ-5D-5L.

PubMed

Ludwig, Kristina; Graf von der Schulenburg, J-Matthias; Greiner, Wolfgang

2018-06-01

The objective of this study was to develop a value set for EQ-5D-5L based on the societal preferences of the German population. As the first country to do so, the study design used the improved EQ-5D-5L valuation protocol 2.0 developed by the EuroQol Group, including a feedback module as internal validation and a quality control process that was missing in the first wave of EQ-5D-5L valuation studies. A representative sample of the general German population (n = 1158) was interviewed using a composite time trade-off and a discrete choice experiment under close quality control. Econometric modeling was used to estimate values for all 3125 possible health states described by EQ-5D-5L. The value set was based on a hybrid model including all available information from the composite time trade-off and discrete choice experiment valuations without any exclusions due to data issues. The final German value set was constructed from a combination of a conditional logit model for the discrete choice experiment data and a censored at -1 Tobit model for the composite time trade-off data, correcting for heteroskedasticity. The value set had logically consistent parameter estimates (p < 0.001 for all coefficients). The predicted EQ-5D-5L index values ranged from -0.661 to 1. This study provided values for the health states of the German version of EQ-5D-5L representing the preferences of the German population. The study successfully employed for the first time worldwide the improved protocol 2.0. The value set enables the use of the EQ-5D-5L instrument in economic evaluations and in clinical studies.

Societal preferences for rheumatoid arthritis treatments: evidence from a discrete choice experiment.

PubMed

Harrison, Mark; Marra, Carlo; Shojania, Kam; Bansback, Nick

2015-10-01

There is a concern that cost-effectiveness analysis using quality-adjusted life years does not capture all valuable benefits of treatments. The objective of this study was to determine the value society places on aspects of RA treatment to inform policymaking. A discrete choice experiment was administered to a representative sample of the Canadian general population. The discrete choice experiment, developed using focus groups, had seven attributes (route and frequency of administration, chance of benefit, chance of serious and minor side effects, confidence in evidence and life expectancy). A conditional logit regression model was used to estimate the significance and relative importance of attributes in influencing preferences on the quality-adjusted life years scale. Responses from 733 respondents who provided rational responses were analysed. Six attribute levels within four attributes significantly influenced preferences for treatments: a willingness to trade a year of life expectancy over a 10-year period to increase the probability of benefiting from treatment, or two-thirds of a year to reduce minor or serious side effects to the lowest level or improve the confidence in benefit/side-effect estimates. There was also some evidence of a preference for oral drug delivery, though a subgroup analysis suggested this preference was restricted to injection-naive respondents. Our results suggest society values the degree of confidence in the estimates of risks and benefits of RA treatments and the route of administration, as well as benefits and side effects. This study provides important evidence to policymakers determining the cost-effectiveness of treatments in arthritis. © The Author 2015. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Men's preferences for the treatment of lower urinary tract symptoms associated with benign prostatic hyperplasia: a discrete choice experiment.

PubMed

Mankowski, Colette; Ikenwilo, Divine; Heidenreich, Sebastian; Ryan, Mandy; Nazir, Jameel; Newman, Cathy; Watson, Verity

2016-01-01

To explore and quantify men's preferences and willingness to pay (WTP) for attributes of medications for lower urinary tract symptoms associated with benign prostatic hyperplasia using a discrete choice experiment. Men in the UK aged ≥45 years with moderate-to-severe lower urinary tract symptoms/benign prostatic hyperplasia (based on self-reported International Prostate Symptom Score ≥8) were recruited. An online discrete choice experiment survey was administered. Eligible men were asked to consider different medication scenarios and select their preferred medication according to seven attributes: daytime and nighttime (nocturia) urinary frequency, urinary urgency, sexual and nonsexual side effects, number of tablets/day, and cost/month. A mixed-logit model was used to estimate preferences and WTP for medication attributes. In all, 247 men completed the survey. Men were willing to trade-off symptom improvements and treatment side effects. Men preferred medications that reduced urinary urgency and reduced day- and nighttime urinary frequency. Men preferred medications without side effects (base-case level), but did not care about the number of tablets per day. WTP for symptomatic improvement was £25.33/month for reduced urgency (urge incontinence to mild urgency), and £6.65/month and £1.39/month for each unit reduction in night- and daytime urination frequency, respectively. The sexual and nonsexual side effects reduced WTP by up to £30.07/month. There was significant heterogeneity in preferences for most attributes, except for reduced urinary urgency from urge incontinence to mild urgency and no fluid during ejaculation (dry orgasm). To compensate for side effects, a medicine for lower urinary tract symptoms/benign prostatic hyperplasia must provide a combination of benefits, such as reduced urgency of urination plus reduced nighttime and/or reduced daytime urination.

Preferences for policy options for cannabis in an Australian general population: A discrete choice experiment.

PubMed

Shanahan, Marian; Gerard, Karen; Ritter, Alison

2014-07-01

Policy choices for illicit drugs such as cannabis entail consideration of competing factors such as individual health, societal views about pleasure, and criminal justice impacts. Society must weigh up these factors in determining the preferred cannabis policy; although often cast as a contest between legalisation of cannabis or full prohibition the actual policy choices are not so black and white. This study assessed societal preferences for different cannabis policies and multiple consequences. A discrete choice experiment (DCE) quantified value-based preferences for alternative cannabis policies described by the five key attributes legal status, health harms, criminal justice service costs, rates of cannabis use and purchase location. An online survey was conducted on a population sample of 1020 Australians. The analytical model was based on stated choices for Policy A, B or Current Policy. The results revealed a strong general preference for either civil penalties or legalisation compared to cannabis cautioning (Current Policy) and a strong dislike of criminalising possession and use of cannabis. Results also demonstrate difference in preferences among those with different demographics and beliefs. Understanding these nuances help to quantify the range of preferences held within the population and can be used to inform policy. This is the first known DCE survey applied to the area of illicit drugs policy. It demonstrates the public hold disparate views on the most appropriate status for cannabis offences and they are able to make trade-offs between policy choices and outcomes in complex areas of social policy. Copyright © 2014 Elsevier B.V. All rights reserved.

Consumer preferences for health and nonhealth outcomes of health promotion: results from a discrete choice experiment.

PubMed

Alayli-Goebbels, Adrienne F G; Dellaert, Benedict G C; Knox, Stephanie A; Ament, André J H A; Lakerveld, Jeroen; Bot, Sandra D M; Nijpels, G; Severens, J L

2013-01-01

Health promotion (HP) interventions have outcomes that go beyond health. Such broader nonhealth outcomes are usually neglected in economic evaluation studies. To allow for their consideration, insights are needed into the types of nonhealth outcomes that HP interventions produce and their relative importance compared with health outcomes. This study explored consumer preferences for health and nonhealth outcomes of HP in the context of lifestyle behavior change. A discrete choice experiment was conducted among participants in a lifestyle intervention (n = 132) and controls (n = 141). Respondents made 16 binary choices between situations that can be experienced after lifestyle behavior change. The situations were described by 10 attributes: future health state value, start point of future health state, life expectancy, clothing size above ideal, days with sufficient relaxation, endurance, experienced control over lifestyle choices, lifestyle improvement of partner and/or children, monetary cost per month, and time cost per week. With the exception of "time cost per week" and "start point of future health state," all attributes significantly determined consumer choices. Thus, both health and nonhealth outcomes affected consumer choice. Marginal rates of substitution between the price attribute and the other attributes revealed that the attributes "endurance," "days with sufficient relaxation," and "future health state value" had the greatest impact on consumer choices. The "life expectancy" attribute had a relatively low impact and for increases of less than 3 years, respondents were not willing to trade. Health outcomes and nonhealth outcomes of lifestyle behavior change were both important to consumers in this study. Decision makers should respond to consumer preferences and consider nonhealth outcomes when deciding about HP interventions. Copyright © 2013 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Using a discrete choice experiment to value the QLU-C10D: feasibility and sensitivity to presentation format.

PubMed

Norman, R; Viney, R; Aaronson, N K; Brazier, J E; Cella, D; Costa, D S J; Fayers, P M; Kemmler, G; Peacock, S; Pickard, A S; Rowen, D; Street, D J; Velikova, G; Young, T A; King, M T

2016-03-01

To assess the feasibility of using a discrete choice experiment (DCE) to value health states within the QLU-C10D, a utility instrument derived from the QLQ-C30, and to assess clarity, difficulty, and respondent preference between two presentation formats. We ran a DCE valuation task in an online panel (N = 430). Respondents answered 16 choice pairs; in half of these, differences between dimensions were highlighted, and in the remainder, common dimensions were described in text and differing attributes were tabulated. To simplify the cognitive task, only four of the QLU-C10D's ten dimensions differed per choice set. We assessed difficulty and clarity of the valuation task with Likert-type scales, and respondents were asked which format they preferred. We analysed the DCE data by format with a conditional logit model and used Chi-squared tests to compare other responses by format. Semi-structured telephone interviews (N = 8) explored respondents' cognitive approaches to the valuation task. Four hundred and forty-nine individuals were recruited, 430 completed at least one choice set, and 422/449 (94 %) completed all 16 choice sets. Interviews revealed that respondents found ten domains difficult but manageable, many adopting simplifying heuristics. Results for clarity and difficulty were identical between formats, but the "highlight" format was preferred by 68 % of respondents. Conditional logit parameter estimates were monotonic within domains, suggesting respondents were able to complete the DCE sensibly, yielding valid results. A DCE valuation task in which only four of the QLU-C10D's ten dimensions differed in any choice set is feasible for deriving utility weights for the QLU-C10D.

Simulation study to determine the impact of different design features on design efficiency in discrete choice experiments.

PubMed

Vanniyasingam, Thuva; Cunningham, Charles E; Foster, Gary; Thabane, Lehana

2016-07-19

Discrete choice experiments (DCEs) are routinely used to elicit patient preferences to improve health outcomes and healthcare services. While many fractional factorial designs can be created, some are more statistically optimal than others. The objective of this simulation study was to investigate how varying the number of (1) attributes, (2) levels within attributes, (3) alternatives and (4) choice tasks per survey will improve or compromise the statistical efficiency of an experimental design. A total of 3204 DCE designs were created to assess how relative design efficiency (d-efficiency) is influenced by varying the number of choice tasks (2-20), alternatives (2-5), attributes (2-20) and attribute levels (2-5) of a design. Choice tasks were created by randomly allocating attribute and attribute level combinations into alternatives. Relative d-efficiency was used to measure the optimality of each DCE design. DCE design complexity influenced statistical efficiency. Across all designs, relative d-efficiency decreased as the number of attributes and attribute levels increased. It increased for designs with more alternatives. Lastly, relative d-efficiency converges as the number of choice tasks increases, where convergence may not be at 100% statistical optimality. Achieving 100% d-efficiency is heavily dependent on the number of attributes, attribute levels, choice tasks and alternatives. Further exploration of overlaps and block sizes are needed. This study's results are widely applicable for researchers interested in creating optimal DCE designs to elicit individual preferences on health services, programmes, policies and products. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Development of Proportional Reasoning: Where Young Children Go Wrong

PubMed Central

Boyer, Ty W.; Levine, Susan C.; Huttenlocher, Janellen

2008-01-01

Previous studies have found that children have difficulty solving proportional reasoning problems involving discrete units until 10- to 12-years of age, but can solve parallel problems involving continuous quantities by 6-years of age. The present studies examine where children go wrong in processing proportions that involve discrete quantities. A computerized proportional equivalence choice task was administered to kindergartners through fourth-graders in Study 1, and to first- and third-graders in Study 2. Both studies involved four between-subjects conditions that were formed by pairing continuous and discrete target proportions with continuous and discrete choice alternatives. In Study 1, target and choice alternatives were presented simultaneously and in Study 2 target and choice alternatives were presented sequentially. In both studies, children performed significantly worse when both the target and choice alternatives were represented with discrete quantities than when either or both of the proportions involved continuous quantities. Taken together, these findings indicate that children go astray on proportional reasoning problems involving discrete units only when a numerical match is possible, suggesting that their difficulty is due to an overextension of numerical equivalence concepts to proportional equivalence problems. PMID:18793078

Contraceptive preferences and use among auto artisanal workers in the informal sector of Kumasi, Ghana: a discrete choice experiment.

PubMed

Agyei-Baffour, Peter; Boahemaa, Mary Yaa; Addy, Ernestine A

2015-04-12

Contraceptive uptake in Ghana, especially in the Ashanti region remains low. This may be partly due to products' characteristics and choice which are influenced by attribute utility trade-offs by consumers in determining which method offers the optimal combinations, given the needs and desires of the individuals making the choice. The study sought to determine how specific attributes of contraceptives influence artisanal auto mechanics' stated preferences for a hypothetical contraceptive use in the Tafo-Suame industrial area of Kumasi, Ghana. A discrete choice experiment was conducted with artisanal auto mechanics in the study area from May to September 2011. Based on the summary of the attributes from the focus group discussion and in-depth interviews preceded administration of structured questionnaire, a discrete choice experiment (DCE) was created. The attributes used were; side effects, reversibility, ease of use, ability to prevent both pregnancy and sexually transmitted infection (STI's), price and privacy in acquiring and attractiveness of the method. A total of 340 consented respondents aged 15 to 49 years participated in the study. Data were entered in Access and Sawtooth software SSI Web CAPi module and then exported to Stata for analysis. The study showed a universal (99.4%) knowledge on contraception, ever used 87% and currently using a method, 58%. The study revealed that methods' reversibility (β = 21.74; 95% CI: 20.17, 23.3), minimal allergic reaction (β = 13.93; 95% CI: 12.8, 15.05) and no effect on blood pressure (β = 12.71; 95% CI: 11.62, 13.79), were strongly associated with contraceptive preference and use. While contraceptives' ability to prevent "only pregnancy", (β = -15.13: 95% CI: -16.2, -14.02; "only STI's") (β = -11.65; 95% CI: -11.84, -11.46); and interrupt during sexual activity (β = -4.26; 95% CI: -5.19, -3.34), had large negative influence on contraceptive preference and use. The study has documented the magnitude of the effects of contraceptive attributes on informed choice, use, preference. It revealed that reversibility, side effects and ability to prevent both pregnancy and STI's are the major important attributes that. The findings have implications on contraceptive development, uptake and the implementation of other family planning programmes.

Reimagining cost recovery in Pakistan's irrigation system through willingness-to-pay estimates for irrigation water from a discrete choice experiment

NASA Astrophysics Data System (ADS)

Bell, Andrew Reid; Shah, M. Azeem Ali; Ward, Patrick S.

2014-08-01

It is widely argued that farmers are unwilling to pay adequate fees for surface water irrigation to recover the costs associated with maintenance and improvement of delivery systems. In this paper, we use a discrete choice experiment to study farmer preferences for irrigation characteristics along two branch canals in Punjab Province in eastern Pakistan. We find that farmers are generally willing to pay well in excess of current surface water irrigation costs for increased surface water reliability and that the amount that farmers are willing to pay is an increasing function of their existing surface water supply as well as location along the main canal branch. This explicit translation of implicit willingness-to-pay (WTP) for water (via expenditure on groundwater pumping) to WTP for reliable surface water demonstrates the potential for greatly enhanced cost recovery in the Indus Basin Irrigation System via appropriate setting of water user fees, driven by the higher WTP of those currently receiving reliable supplies.

Reimagining cost recovery in Pakistan's irrigation system through willingness-to-pay estimates for irrigation water from a discrete choice experiment

PubMed Central

Bell, Andrew Reid; Shah, M Azeem Ali; Ward, Patrick S

2014-01-01

It is widely argued that farmers are unwilling to pay adequate fees for surface water irrigation to recover the costs associated with maintenance and improvement of delivery systems. In this paper, we use a discrete choice experiment to study farmer preferences for irrigation characteristics along two branch canals in Punjab Province in eastern Pakistan. We find that farmers are generally willing to pay well in excess of current surface water irrigation costs for increased surface water reliability and that the amount that farmers are willing to pay is an increasing function of their existing surface water supply as well as location along the main canal branch. This explicit translation of implicit willingness-to-pay (WTP) for water (via expenditure on groundwater pumping) to WTP for reliable surface water demonstrates the potential for greatly enhanced cost recovery in the Indus Basin Irrigation System via appropriate setting of water user fees, driven by the higher WTP of those currently receiving reliable supplies. PMID:25552779

End-of-life healthcare expenditure: Testing economic explanations using a discrete choice experiment.

PubMed

Fischer, Barbara; Telser, Harry; Zweifel, Peter

2018-06-07

Healthcare expenditure (HCE) spent during an individual's last year of life accounts for a high share of lifetime HCE. This finding is puzzling because an investment in health is unlikely to have a sufficiently long payback period. However, Becker et al. (2007) and Philipson et al. (2010) have advanced a theory designed to explain high willingness to pay (WTP) for an extension of life close to its end. Their testable implications are complemented by the concept of 'pain of risk bearing' introduced by Eeckhoudt and Schlesinger (2006). They are tested using a discrete choice experiment performed in 2014, involving 1,529 Swiss adults. An individual setting where the price attribute is substantial out-of-pocket payment for a novel drug for treatment of terminal cancer is distinguished from a societal one, where it is an increase in contributions to social health insurance. Most of the economic predictions receive empirical support. Copyright © 2018. Published by Elsevier B.V.

A discrete choice experiment investigating preferences for funding drugs used to treat orphan diseases: an exploratory study.

PubMed

Mentzakis, Emmanouil; Stefanowska, Patricia; Hurley, Jeremiah

2011-07-01

Policy debate about funding criteria for drugs used to treat rare, orphan diseases is gaining prominence. This study presents evidence from a discrete choice experiment using a convenience sample of university students to investigate individual preferences regarding public funding for drugs used to treat rare diseases and common diseases. This pilot study finds that: other things equal, the respondents do not prefer to have the government spend more for drugs used to treat rare diseases; that respondents are not willing to pay more per life year gained for a rare disease than a common disease; and that respondents weigh relevant attributes of the coverage decisions (e.g. costs, disease severity and treatment effectiveness) similarly for both rare and common diseases. The results confirm the importance of severity and treatment effectiveness in preferences for public funding. Although this is the first study of its kind, the results send a cautionary message regarding the special treatment of orphan drugs in coverage decision-making.

Patients’ preferences for GP consultation for perceived cancer risk in primary care: a discrete choice experiment

PubMed Central

Whitaker, Katriina L; Ghanouni, Alex; Zhou, Yin; Lyratzopoulos, Georgios; Morris, Stephen

2017-01-01

Background Contacting a doctor for advice when experiencing a potential cancer symptom is an important step in early diagnosis, but barriers to consultation are commonly reported. Understanding barriers to consulting in primary care within the cancer context provides opportunities to improve earlier diagnosis of cancer Aim To investigate patients’ GP consultation preferences when presented with a potential cancer symptom, and to describe whether these preferences are mediated by variable levels of cancer risk. Design and setting A UK-wide online survey of adults ≥50 years old, using quota sampling to reflect general population characteristics. Method A discrete choice experiment examined participants’ preferences for primary care consultation for three cancer symptom scenarios: risk level not mentioned, risk designated as ‘low’, or risk designated as ‘high’. Scenarios based on length of consultation, time to getting an appointment, convenience, choice of GP, and GP listening skills were presented in a self-completed online questionnaire. Results A total of 9616 observations were obtained from 601 participants. Participants expressed preferences for doctors with better listening skills, the ability to see a GP of their choice, and shorter waiting times. These findings were the same across risk conditions and demographic groups. Participants were willing to wait an extra 3.5 weeks for an appointment with a doctor with good/very good listening skills (versus very poor listening skills) and an extra week for an appointment with a GP of their choice (versus any GP). Conclusion Patient decisions about help seeking seem to be particularly influenced by the anticipated listening skills of doctors. Improving doctors’ communication skills may in the longer term encourage people to seek prompt medical help when they experience a cancer symptom. PMID:28483824

Patient Preferences for Features of Health Care Delivery Systems: A Discrete Choice Experiment.

PubMed

Mühlbacher, Axel C; Bethge, Susanne; Reed, Shelby D; Schulman, Kevin A

2016-04-01

To estimate the relative importance of organizational-, procedural-, and interpersonal-level features of health care delivery systems from the patient perspective. We designed four discrete choice experiments (DCEs) to measure patient preferences for 21 health system attributes. Participants were recruited through the online patient portal of a large health system. We analyzed the DCE data using random effects logit models. DCEs were performed in which respondents were provided with descriptions of alternative scenarios and asked to indicate which scenario they prefer. Respondents were randomly assigned to one of the three possible health scenarios (current health, new lung cancer diagnosis, or diabetes) and asked to complete 15 choice tasks. Each choice task included an annual out-of-pocket cost attribute. A total of 3,900 respondents completed the survey. The out-of-pocket cost attribute was considered the most important across the four different DCEs. Following the cost attribute, trust and respect, multidisciplinary care, and shared decision making were judged as most important. The relative importance of out-of-pocket cost was consistently lower in the hypothetical context of a new lung cancer diagnosis compared with diabetes or the patient's current health. This study demonstrates the complexity of patient decision making processes regarding features of health care delivery systems. Our findings suggest the importance of these features may change as a function of an individual's medical conditions. © Health Research and Educational Trust.

Discrete Choice Modeling (DCM): An Exciting Marketing Research Survey Method for Educational Researchers.

ERIC Educational Resources Information Center

Berdie, Doug R.

Discrete Choice Marketing (DCM), a research technique that has become more popular in recent marketing research, is described. DCM is a method that forces people to look at the combination of relevant variables within each choice domain and, with each option fully defined in terms of the values for those variables, make a choice of options. DCM…

Factors affecting food choices of older adults from high and low socioeconomic groups: a discrete choice experiment.

PubMed

Kamphuis, Carlijn B M; de Bekker-Grob, Esther W; van Lenthe, Frank J

2015-04-01

Healthiness, price, and convenience are typically indicated as important motives for food choices; however, it is largely unknown to what extent older adults from high and low socioeconomic groups differ in these underlying motives. A discrete choice experiment (DCE) is an innovative way to elicit implicit motives for food choices. The aim was to investigate differences in food motives between socioeconomic groups by means of a DCE. A DCE was carried out during a face-to-face interview among older adults as part of the Health and Living Conditions in Eindhoven and surrounding cities (GLOBE) cohort study, The Netherlands. Participants (n = 399; mean age: 63.3 y) were offered a series of choice sets about a usual dinner at home and were asked to choose in each choice set between 2 meals and an opt-out choice, with different combinations of attribute levels. We included 5 meal attributes (taste, healthiness, preparation time, travel time to shops, and price) and 3 or 4 levels for each attribute. Data were analyzed by multinomial logit models. Healthiness, taste, price, and travel time to the grocery store proved to significantly influence older adults' meal decisions; preparation time was not significant. Healthiness was the most important attribute for all of the participants. More highly educated participants rated a healthy and less expensive meal to be more important than did less educated participants. Those with a high income rated a meal that was healthy and very tasteful to be more important than did those with a lower income. Healthiness, taste, price, and travel time to grocery shops influenced older adults' meal decisions. Higher socioeconomic groups valued health more than did lower socioeconomic groups. DCEs represent a promising method to gain insight into the relative importance of motives for food choices. This trial was registered at www.isrctn.com as ISRCTN60293770. © 2015 American Society for Nutrition.

Patient and nurse preferences for implementation of bedside handover: Do they agree? Findings from a discrete choice experiment.

PubMed

Whitty, Jennifer A; Spinks, Jean; Bucknall, Tracey; Tobiano, Georgia; Chaboyer, Wendy

2017-08-01

To describe and compare patients' and nurses' preferences for the implementation of bedside handover. Discrete choice experiment describing handover choices using six characteristics: whether the patient is invited to participate; whether a family member/carer/friend is invited; the number of nurses present; the level of patient involvement; the information content; and privacy. Two Australian hospitals. Adult patients (n=401) and nurses (n=200) recruited from medical wards. Mean importance scores for handover characteristics estimated using mixed multinomial logit regression of the choice data. Both patient and nurse participants preferred handover at the bedside rather than elsewhere (P<.05). Being invited to participate, supporting strong two-way communication, having a family member/carer/friend present and having two nurses rather than the nursing team present were most important for patients. Patients being invited to participate and supporting strong two-way communication were most important for nurses. However, contrary to patient preferences, having a family member/carer/friend present was not considered important by nurses. Further, while patients expressed a weak preference to have sensitive information handed over quietly at the bedside, nurses expressed a relatively strong preference for handover of sensitive information verbally away from the bedside. All participants strongly support handover at the bedside and want patients to participate although patient and nurse preferences for various aspects of bedside handover differ. An understanding of these preferences is expected to support recommendations for improving the patient hospital experience and the consistent implementation of bedside handover as a safety initiative. © 2016 The Authors. Health Expectations Published by John Wiley & Sons Ltd.

Valuing SF-6D Health States Using a Discrete Choice Experiment.

PubMed

Norman, Richard; Viney, Rosalie; Brazier, John; Burgess, Leonie; Cronin, Paula; King, Madeleine; Ratcliffe, Julie; Street, Deborah

2014-08-01

SF-6D utility weights are conventionally produced using a standard gamble (SG). SG-derived weights consistently demonstrate a floor effect not observed with other elicitation techniques. Recent advances in discrete choice methods have allowed estimation of utility weights. The objective was to produce Australian utility weights for the SF-6D and to explore the application of discrete choice experiment (DCE) methods in this context. We hypothesized that weights derived using this method would reflect the largely monotonic construction of the SF-6D. We designed an online DCE and administered it to an Australia-representative online panel (n = 1017). A range of specifications investigating nonlinear preferences with respect to additional life expectancy were estimated using a random-effects probit model. The preferred model was then used to estimate a preference index such that full health and death were valued at 1 and 0, respectively, to provide an algorithm for Australian cost-utility analyses. Physical functioning, pain, mental health, and vitality were the largest drivers of utility weights. Combining levels to remove illogical orderings did not lead to a poorer model fit. Relative to international SG-derived weights, the range of utility weights was larger with 5% of health states valued below zero. s. DCEs can be used to investigate preferences for health profiles and to estimate utility weights for multi-attribute utility instruments. Australian cost-utility analyses can now use domestic SF-6D weights. The comparability of DCE results to those using other elicitation methods for estimating utility weights for quality-adjusted life-year calculations should be further investigated. © The Author(s) 2013.

How Much Credence Does It Take? Evidence on the Trade-Off between Country-Of-Origin Information and Credence Attributes for Beef from a Choice Experiment in Sweden

PubMed Central

Hess, Sebastian; Johansson, Helena

2017-01-01

Based on a discrete choice experiment with 336 consumers, this study investigated whether the consumer propensity to choose a simplified European Union (EU) vs. non-EU denomination of origin for beef, instead of a specific country-of-origin (COO) denomination, depends upon the amount and type of credence information provided to the individual. The likelihood of choosing the EU/non-EU denomination of origin depended on the total number of other labelling credence attributes provided and also on the type of detailed credence attributes present in the choice. The presence of cues relating to animal welfare and far-reaching traceability had the highest likelihood of influencing the choice of the EU/non-EU denomination of origin. The compensatory qualities of each credence attribute in relation to the EU/non-EU origin denomination thus differed. PMID:28946674

How Can the Health System Retain Women in HIV Treatment for a Lifetime? A Discrete Choice Experiment in Ethiopia and Mozambique

PubMed Central

Kruk, Margaret E.; Riley, Patricia L.; Palma, Anton M.; Adhikari, Sweta; Ahoua, Laurence; Arnaldo, Carlos; Belo, Dercio F.; Brusamento, Serena; Cumba, Luisa I. G.; Dziuban, Eric J.; El-Sadr, Wafaa M.; Gutema, Yoseph; Habtamu, Zelalem; Heller, Thomas; Kidanu, Aklilu; Langa, Judite; Mahagaja, Epifanio; McCarthy, Carey F.; Melaku, Zenebe; Shodell, Daniel; Tsiouris, Fatima; Young, Paul R.; Rabkin, Miriam

2016-01-01

Introduction Option B+, an approach that involves provision of antiretroviral therapy (ART) to all HIV-infected pregnant women for life, is the preferred strategy for prevention of mother to child transmission of HIV. Lifelong retention in care is essential to its success. We conducted a discrete choice experiment in Ethiopia and Mozambique to identify health system characteristics preferred by HIV-infected women to promote continuity of care. Methods Women living with HIV and receiving care at hospitals in Oromia Region, Ethiopia and Zambézia Province, Mozambique were shown nine choice cards and asked to select one of two hypothetical health facilities, each with six varying characteristics related to the delivery of HIV services for long term treatment. Mixed logit models were used to estimate the influence of six health service attributes on choice of clinics. Results 2,033 women participated in the study (response rate 97.8% in Ethiopia and 94.7% in Mozambique). Among the various attributes of structure and content of lifelong ART services, the most important attributes identified in both countries were respectful provider attitude and ability to obtain non-HIV health services during HIV-related visits. Availability of counseling support services was also a driver of choice. Facility type, i.e., hospital versus health center, was substantially less important. Conclusions Efforts to enhance retention in HIV care and treatment for pregnant women should focus on promoting respectful care by providers and integrating access to non-HIV health services in the same visit, as well as continuing to strengthen counseling. PMID:27551785

Acceptability and Preferences for Hypothetical Rectal Microbicides among a Community Sample of Young Men Who Have Sex with Men and Transgender Women in Thailand: A Discrete Choice Experiment.

PubMed

Newman, Peter A; Cameron, Michael P; Roungprakhon, Surachet; Tepjan, Suchon; Scarpa, Riccardo

2016-11-01

Rectal microbicides (RMs) may offer substantial benefits in expanding HIV prevention options for key populations. From April to August 2013, we conducted Tablet-Assisted Survey Interviewing, including a discrete choice experiment, with participants recruited from gay entertainment venues and community-based organizations in Chiang Mai and Pattaya, Thailand. Among 408 participants, 74.5 % were young men who have sex with men, 25.5 % transgender women, with mean age = 24.3 years. One-third (35.5 %) had ≤9th grade education; 63.4 % engaged in sex work. Overall, 83.4 % reported they would definitely use a RM, with more than 2-fold higher odds of choice of a RM with 99 versus 50 % efficacy, and significantly higher odds of choosing gel versus suppository, intermittent versus daily dosing, and prescription versus over-the-counter. Sex workers were significantly more likely to use a RM immediately upon availability, with greater tolerance for moderate efficacy and daily dosing. Engaging key populations in assessing RM preferences may support biomedical research and evidence-informed interventions to optimize the effectiveness of RMs in HIV prevention.

Incentives for Blood Donation: A Discrete Choice Experiment to Analyze Extrinsic Motivation.

PubMed

Sadler, Andrew; Shi, Ling; Bethge, Susanne; Mühlbacher, Axel

2018-04-01

Background: Demographic trends affect size and age structure of populations. One of the consequences will be an increasing need for blood products to treat age-related diseases. Donation services rely on voluntariness and charitable motivation. It might be questioned whether there will be sufficient blood supply with voluntary donation. The present study focused on elicitation of preferences for incentives and aimed to contribute to the discussion on how to increase donation rates. Methods: A self-administered discrete choice experiment (DCE) was applied. Respondents were repeatedly asked to choose between hypothetical blood donation centers. In case of reluctance to receiving incentives a none-option was included. Random parameter logit (RPL) and latent class models (LCM) were used for analysis. Results: The study sample included 416 college students from the US and Germany. Choice decisions were significantly influenced by the characteristics of the donation center in the DCE. Incentives most preferred were monetary compensation, paid leave, and blood screening test. LCM identified subgroups with preference heterogeneity. Small subgroups indicated moderate to strong aversion to incentives. Conclusion: The majority of the sample positively responded to incentives and indicated a willingness to accept incentives. In face of future challenges, the judicious use and appropriate utilization of incentives might be an option to motivate potential donors and should be open to discussion.

The cost-effectiveness and consumer acceptability of taxation strategies to reduce rates of overweight and obesity among children in Australia: study protocol.

PubMed

Comans, Tracy A; Whitty, Jennifer A; Hills, Andrew P; Kendall, Elizabeth; Turkstra, Erika; Gordon, Louisa G; Byrnes, Josh M; Scuffham, Paul A

2013-12-14

Childhood obesity is a recognised public health problem and around 25% of Australian children are overweight or obese. A major contributor is the obesogenic environment which encourages over consumption of energy dense nutrient poor food. Taxation is commonly proposed as a mechanism to reduce consumption of poor food choices and hence reduce rates of obesity and overweight in the community. An economic model will be developed to assess the lifetime benefits and costs to a cohort of Australian children by reducing energy dense nutrient poor food consumption through taxation mechanisms. The model inputs will be derived from a series of smaller studies. Food options for taxation will be derived from literature and expert opinion, the acceptability and impact of price changes will be explored through a Citizen's Jury and a discrete choice experiment and price elasticities will be derived from the discrete choice experiment and consumption data. The health care costs of managing rising levels of obesity are a challenge for all governments. This study will provide a unique contribution to the international knowledge base by engaging a variety of robust research techniques, with a multidisciplinary focus and be responsive to consumers from diverse socio-economic backgrounds.

Employment preferences of public sector nurses in Malawi: results from a discrete choice experiment.

PubMed

Mangham, Lindsay J; Hanson, Kara

2008-12-01

To understand the employment preferences of Malawian public sector registered nurses, and to ascertain whether salary increases significantly affect how nurses regard their employment. A discrete choice experiment was used to assess the significance of six job attributes on nurses' preferences over pairs of job descriptions: net monthly pay, provision of government housing, opportunities to upgrade their qualifications, typical workload, availability of resources and place of work. A multivariate model was used to estimate the extent to which nurses were willing to trade between their monetary benefits, non-monetary benefits, and working conditions, and to determine the relative importance of the job attributes. Most nurses were willing to trade among attributes, and very few appeared to have preferences that were dominated by a single job attribute. All attributes had a statistically significant influence on nurses' preferences, and further analysis showed the rate at which they were willing to forego pay increases for other improvements in their employment conditions. Opportunities to upgrade professional qualifications, government housing and the increases in net monthly pay had the greatest impact on nurses' employment choices. Salary enhancement can improve the motivation and retention of nurses, as well as improvements of employment conditions, which support existing efforts to address the health worker shortage.

A systematic review of the reliability and validity of discrete choice experiments in valuing non-market environmental goods.

PubMed

Rakotonarivo, O Sarobidy; Schaafsma, Marije; Hockley, Neal

2016-12-01

While discrete choice experiments (DCEs) are increasingly used in the field of environmental valuation, they remain controversial because of their hypothetical nature and the contested reliability and validity of their results. We systematically reviewed evidence on the validity and reliability of environmental DCEs from the past thirteen years (Jan 2003-February 2016). 107 articles met our inclusion criteria. These studies provide limited and mixed evidence of the reliability and validity of DCE. Valuation results were susceptible to small changes in survey design in 45% of outcomes reporting reliability measures. DCE results were generally consistent with those of other stated preference techniques (convergent validity), but hypothetical bias was common. Evidence supporting theoretical validity (consistency with assumptions of rational choice theory) was limited. In content validity tests, 2-90% of respondents protested against a feature of the survey, and a considerable proportion found DCEs to be incomprehensible or inconsequential (17-40% and 10-62% respectively). DCE remains useful for non-market valuation, but its results should be used with caution. Given the sparse and inconclusive evidence base, we recommend that tests of reliability and validity are more routinely integrated into DCE studies and suggest how this might be achieved. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

The cost-effectiveness and consumer acceptability of taxation strategies to reduce rates of overweight and obesity among children in Australia: study protocol

PubMed Central

2013-01-01

Background Childhood obesity is a recognised public health problem and around 25% of Australian children are overweight or obese. A major contributor is the obesogenic environment which encourages over consumption of energy dense nutrient poor food. Taxation is commonly proposed as a mechanism to reduce consumption of poor food choices and hence reduce rates of obesity and overweight in the community. Methods/Design An economic model will be developed to assess the lifetime benefits and costs to a cohort of Australian children by reducing energy dense nutrient poor food consumption through taxation mechanisms. The model inputs will be derived from a series of smaller studies. Food options for taxation will be derived from literature and expert opinion, the acceptability and impact of price changes will be explored through a Citizen’s Jury and a discrete choice experiment and price elasticities will be derived from the discrete choice experiment and consumption data. Discussion The health care costs of managing rising levels of obesity are a challenge for all governments. This study will provide a unique contribution to the international knowledge base by engaging a variety of robust research techniques, with a multidisciplinary focus and be responsive to consumers from diverse socio-economic backgrounds. PMID:24330325

Providing Information to Parents of Children with Mental Health Problems: A Discrete Choice Conjoint Analysis of Professional Preferences

ERIC Educational Resources Information Center

Cunningham, Charles E.; Deal, Ken; Rimas, Heather; Chen, Yvonne; Buchanan, Don H.; Sdao-Jarvie, Kathie

2009-01-01

We used discrete choice conjoint analysis to model the ways 645 children's mental health (CMH) professionals preferred to provide information to parents seeking CMH services. Participants completed 20 choice tasks presenting experimentally varied combinations of the study's 14 4-level CMH information transfer attributes. Latent class analysis…

Emerging Australian Education Markets: A Discrete Choice Model of Taiwanese and Indonesian Student Intended Study Destination.

ERIC Educational Resources Information Center

Kemp, Steven; Madden, Gary; Simpson, Michael

1998-01-01

Isolates factors influencing choice of Australia as a preferred destination for international students in emerging regional markets. Uses data obtained from a survey of students in Indonesia and Taiwan to estimate a U.S./Australia and rest-of-world/Australia discrete destination-choice model. This model identifies key factors determining country…

Determinants of the choice of GP practice registration in England: evidence from a discrete choice experiment.

PubMed

Lagarde, Mylene; Erens, Bob; Mays, Nicholas

2015-04-01

There have been growing concerns that general practitioner (GP) services in England, which are based on registration with a single practice located near the patient's home, are not sufficiently convenient for patients. To inform the decision as to whether to change registration rules allowing patients to register 'out-of-area' and to estimate the demand for this wider choice, we undertook a discrete choice experiment with 1706 respondents. Latent class models were used to analyse preferences for GP practice registration comparing preferences for neighbourhood and non-neighbourhood practices. We find that there is some appetite for registering outside the neighbourhood, but this preference is not uniformly shared across the population. Specifically individuals who are less mobile (e.g. older people and those with caring responsibilities), or satisfied with their local practice are less likely to be interested in registering at a practice outside their neighbourhood. Overall, people feel most strongly about obtaining an appointment with a GP as quickly as possible. Respondents regarded weekend opening as less important than other factors, and particularly less important than extended practice opening hours from Monday to Friday. Assuming a constant demand for GP services, a policy encouraging GP practices to extend their opening hours during the week is likely to decrease the average patient waiting time for an appointment and is likely to be preferred by patients. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

What do women want? Valuing women's preferences and estimating demand for alternative models of maternity care using a discrete choice experiment.

PubMed

Fawsitt, Christopher G; Bourke, Jane; Greene, Richard A; McElroy, Brendan; Krucien, Nicolas; Murphy, Rosemary; Lutomski, Jennifer E

2017-11-01

In many countries, there has been a considerable shift towards providing a more woman-centred maternity service, which affords greater consumer choice. Maternity service provision in Ireland is set to follow this trend with policymakers committed to improving maternal choice at hospital level. However, women's preferences for maternity care are unknown, as is the expected demand for new services. In this paper, we used a discrete choice experiment (DCE) to (1) investigate women's strengths of preference for different features of maternity care; (2) predict market uptake for consultant- and midwifery-led care, and a hybrid model of care called the Domiciliary In and Out of Hospital Care scheme; and (3) calculate the welfare change arising from the provision of these services. Women attending antenatal care across two teaching hospitals in Ireland were invited to participate in the study. Women's preferred model of care resembled the hybrid model of care, with considerably more women expected to utilise this service than either consultant- or midwifery-led care. The benefit of providing all three services proved considerably greater than the benefit of providing two or fewer services. From a priority setting perspective, pursuing all three models of care would generate a considerable welfare gain, although the cost-effectiveness of such an approach needs to be considered. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.

Treatment preferences of originator versus biosimilar drugs in Crohn's disease; discrete choice experiment among gastroenterologists.

PubMed

Baji, Petra; Gulácsi, László; Lovász, Barbara D; Golovics, Petra A; Brodszky, Valentin; Péntek, Márta; Rencz, Fanni; Lakatos, Péter L

2016-01-01

To explore preferences of gastroenterologists for biosimilar drugs in Crohn's disease. Discrete choice experiment was carried out involving 51 Hungarian gastroenterologists in May 2014. The following attributes were used to describe hypothetical choice sets: 1) type of the treatment (biosimilar/originator), 2) severity of disease, 3) availability of continuous medicine supply, 4) frequency of the efficacy check-ups. Multinomial logit model was used to differentiate between three attitude types: 1) always opting for the originator, 2) willing to consider biosimilar for biological-naïve patients only, 3) willing to consider biosimilar treatment for both types of patients. Conditional logit model was used to estimate the probabilities of choosing a given profile. Men, senior consultants, working in inflammatory bowel disease center and treating more patients were more likely willing to consider biosimilar for biological-naïve patients only. Treatment type (originator/biosimilar) was the most important determinant of choice for patients already treated with biologicals, and the availability of continuous medicine supply in case of biological-naïve patients. The probabilities of choosing the biosimilar with all the benefits offered over the originator under current reimbursement conditions are 89% versus 11% for new patients, and 44% versus 56% for patients already treated with biological. For gastroenterologist, the continuous medical supply would be one of the major benefits of biosimilars. However, benefits offered in the scenarios do not compensate for the change from the originator to the biosimilar treatment of patients already treated with biologicals.

A practical method to test the validity of the standard Gumbel distribution in logit-based multinomial choice models of travel behavior

DOE PAGES

Ye, Xin; Garikapati, Venu M.; You, Daehyun; ...

2017-11-08

Most multinomial choice models (e.g., the multinomial logit model) adopted in practice assume an extreme-value Gumbel distribution for the random components (error terms) of utility functions. This distributional assumption offers a closed-form likelihood expression when the utility maximization principle is applied to model choice behaviors. As a result, model coefficients can be easily estimated using the standard maximum likelihood estimation method. However, maximum likelihood estimators are consistent and efficient only if distributional assumptions on the random error terms are valid. It is therefore critical to test the validity of underlying distributional assumptions on the error terms that form the basismore » of parameter estimation and policy evaluation. In this paper, a practical yet statistically rigorous method is proposed to test the validity of the distributional assumption on the random components of utility functions in both the multinomial logit (MNL) model and multiple discrete-continuous extreme value (MDCEV) model. Based on a semi-nonparametric approach, a closed-form likelihood function that nests the MNL or MDCEV model being tested is derived. The proposed method allows traditional likelihood ratio tests to be used to test violations of the standard Gumbel distribution assumption. Simulation experiments are conducted to demonstrate that the proposed test yields acceptable Type-I and Type-II error probabilities at commonly available sample sizes. The test is then applied to three real-world discrete and discrete-continuous choice models. For all three models, the proposed test rejects the validity of the standard Gumbel distribution in most utility functions, calling for the development of robust choice models that overcome adverse effects of violations of distributional assumptions on the error terms in random utility functions.« less

A practical method to test the validity of the standard Gumbel distribution in logit-based multinomial choice models of travel behavior

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ye, Xin; Garikapati, Venu M.; You, Daehyun

Most multinomial choice models (e.g., the multinomial logit model) adopted in practice assume an extreme-value Gumbel distribution for the random components (error terms) of utility functions. This distributional assumption offers a closed-form likelihood expression when the utility maximization principle is applied to model choice behaviors. As a result, model coefficients can be easily estimated using the standard maximum likelihood estimation method. However, maximum likelihood estimators are consistent and efficient only if distributional assumptions on the random error terms are valid. It is therefore critical to test the validity of underlying distributional assumptions on the error terms that form the basismore » of parameter estimation and policy evaluation. In this paper, a practical yet statistically rigorous method is proposed to test the validity of the distributional assumption on the random components of utility functions in both the multinomial logit (MNL) model and multiple discrete-continuous extreme value (MDCEV) model. Based on a semi-nonparametric approach, a closed-form likelihood function that nests the MNL or MDCEV model being tested is derived. The proposed method allows traditional likelihood ratio tests to be used to test violations of the standard Gumbel distribution assumption. Simulation experiments are conducted to demonstrate that the proposed test yields acceptable Type-I and Type-II error probabilities at commonly available sample sizes. The test is then applied to three real-world discrete and discrete-continuous choice models. For all three models, the proposed test rejects the validity of the standard Gumbel distribution in most utility functions, calling for the development of robust choice models that overcome adverse effects of violations of distributional assumptions on the error terms in random utility functions.« less

Analysing the Preferences of Prospective Students for Higher Education Institution Attributes

ERIC Educational Resources Information Center

Walsh, Sharon; Flannery, Darragh; Cullinan, John

2018-01-01

We utilise a dataset of students in their final year of upper secondary education in Ireland to provide a detailed examination of the preferences of prospective students for higher education institutions (HEIs). Our analysis is based upon a discrete choice experiment methodology with willingness to pay estimates derived for specific HEI attributes…

Reconceptualising the external validity of discrete choice experiments.

PubMed

Lancsar, Emily; Swait, Joffre

2014-10-01

External validity is a crucial but under-researched topic when considering using discrete choice experiment (DCE) results to inform decision making in clinical, commercial or policy contexts. We present the theory and tests traditionally used to explore external validity that focus on a comparison of final outcomes and review how this traditional definition has been empirically tested in health economics and other sectors (such as transport, environment and marketing) in which DCE methods are applied. While an important component, we argue that the investigation of external validity should be much broader than a comparison of final outcomes. In doing so, we introduce a new and more comprehensive conceptualisation of external validity, closely linked to process validity, that moves us from the simple characterisation of a model as being or not being externally valid on the basis of predictive performance, to the concept that external validity should be an objective pursued from the initial conceptualisation and design of any DCE. We discuss how such a broader definition of external validity can be fruitfully used and suggest innovative ways in which it can be explored in practice.

Discrete choice experiment of smoking cessation behaviour in Japan.

PubMed

Goto, Rei; Nishimura, Shuzo; Ida, Takanori

2007-10-01

In spite of gradual increases in tobacco price and the introduction of laws supporting various anti-tobacco measures, the proportion of smokers in Japan's population is still higher than in other developed nations. To understand what information and individual characteristics drive smokers to attempt to quit smoking. These determinants will help to realise effective tobacco control policy as a base for understanding of cessation behaviour. Discrete choice experiments on a total of 616 respondents registered at a consumer monitoring investigative company. The effect of price is greater on smokers with lower nicotine dependence. For smokers of moderate and low dependency, short term health risks and health risks caused by passive smoking have a strong impact, though the existence of penalties and long term health risks have little influence on smokers' decisions to quit. For highly dependent smokers, non-price attributes have little impact. Furthermore, the effects of age, sex and knowledge are also not uniform in accounting for smoking cessation. Determinants of smoking cessation vary among levels of nicotine dependency. Therefore, how and what information is provided needs to be carefully considered when counselling smokers to help them to quit.

What do nurses and midwives value about their jobs? Results from a discrete choice experiment.

PubMed

Scott, Anthony; Witt, Julia; Duffield, Christine; Kalb, Guyonne

2015-01-01

To examine nurses' and midwives' preferences for the characteristics of their jobs. A discrete choice experiment of 990 nurses and midwives administered as part of a survey of nurses and midwives in Victoria, Australia. Autonomy, working hours, and processes to deal with violence and bullying were valued most highly. Nurses and midwives would be willing to forgo 19% and 16% of their annual income for adequate autonomy and adequate processes to deal with violence and bullying, compared to poor autonomy and poor processes for violence and bullying. They would need to be paid an additional 24% to increase their working hours by 10% ($73 per hour). Job characteristics that were less important were shift work, nurse to patient ratios, and public or private sector work. Policies to improve retention and job satisfaction of nurses and midwives should initially focus on autonomy, processes to deal with violence and bullying, and reasonable working hours. Further research on the cost-effectiveness of these different policies is needed. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Participating physician preferences regarding a pay-for-performance incentive design: a discrete choice experiment.

PubMed

Chen, Tsung-Tai; Lai, Mei-Shu; Chung, Kuo-Piao

2016-02-01

To determine whether the magnitude of incentives or other design attributes should be prioritized and the most important attributes, according to physicians, of the diabetes P4P (pay-for-performance) program design. We implemented a discrete choice experiment (DCE) to elicit the P4P incentive design-related preferences of physicians. All of the physicians (n = 248) who participated in the diabetes P4P program located in the supervisory area of the northern regional branch of the Bureau of National Health Insurance in 2009 were included. The response rate was ∼ 60%. Our research found that the bonus type of incentive was the most important attribute, followed by the incentive structure and the investment magnitude. Physicians may feel that good P4P designs are more important than the magnitude of the investment by the insurer. The two most important P4P designs include providing the bonus type of incentive and using pay-for-excellence plus pay-for-improvement. © The Author 2015. Published by Oxford University Press in association with the International Society for Quality in Health Care; all rights reserved.

Evaluating consumer preferences for healthy eating from Community Kitchens in low-income urban areas: A discrete choice experiment of Comedores Populares in Peru.

PubMed

Buttorff, Christine; Trujillo, Antonio J; Diez-Canseco, Francisco; Bernabe-Ortiz, Antonio; Miranda, J Jaime

2015-09-01

Many low-income individuals from around the world rely on local food vendors for daily sustenance. These small vendors quickly provide convenient, low-priced, tasty foods, however, they may be low in nutritional value. These vendors serve as an opportunity to use established delivery channels to explore the introduction of healthier products, e.g. fresh salad and fruits, to low-income populations. We sought to understand preferences for items prepared in Comedores Populares (CP), government-supported food vendors serving low-income Peruvians, to determine whether it would be feasible to introduce healthier items, specifically fruits and vegetables. We used a best-worst discrete choice experiment (DCE) that allowed participants to select their favorite and least favorite option from a series of three hypothetical menus. The characteristics were derived from a series of formative qualitative interviews conducted previously in the CPs. We examined preferences for six characteristics: price, salad, soup, sides, meat and fruit. A total of 432 individuals, from two districts in Lima, Peru responded to a discrete choice experiment and demographic survey in 2012. For the DCE, price contributed the most to individual's utility relative to the other attributes, with salad and soup following closely. Sides (e.g. rice and beans) were the least important. The willingness to pay for a meal with a large main course and salad was 2.6 Nuevos Soles, roughly a 1 Nuevo Sol increase from the average menu price, or USD $0.32 dollars. The willingness to pay for a meal with fruit was 1.6 Nuevo Soles. Overall, the perceived quality of service and food served in the CPs is high. The willingness to pay indicates that healthier additions to meals are feasible. Understanding consumer preferences can help policy makers design healthier meals in an organization with the potential to scale up to reach a considerable number of low-income families. Copyright © 2015 Elsevier Ltd. All rights reserved.

Criteria for prioritization of HIV programs in Viet Nam: a discrete choice experiment.

PubMed

Safarnejad, Ali; Pavlova, Milena; Son, Vo Hai; Phuong, Huynh Lan; Groot, Wim

2017-11-13

With the decline in funding for Viet Nam's response to the HIV epidemic, there is a need for evidence on the criteria to guide the prioritization of HIV programs. There is a gap in the research on the relative importance of multiple criteria for prioritizing a package of interventions. This study elicits preferences and the trade-offs made between different HIV programs by relevant stakeholders and decision-makers in Viet Nam. It also pays attention to how differences in social and professional characteristics of stakeholders and their agency affiliations shape preferences for HIV program criteria in Viet Nam. This study uses self-explicated ranking and discrete choice experiments to determine the relative importance of five criteria - effectiveness, feasibility, cost-effectiveness, rate of investment and prevention/treatment investment ratio - to stakeholders when they evaluate and select hypothetical HIV programs. The study includes 69 participants from government, civil society, and international development partners. Results of the discrete choice experiment show that overall the feasibility criterion is ranked highest in importance to the participants when choosing a hypothetical HIV program, followed by sustainability, treatment to prevention spending ratio, and effectiveness. The participant's work in management, programming, or decision-making has a significant effect on the importance of some criteria to the participant. In the self-explicated ranking effectiveness is the most important criterion and the cost-effectiveness criterion ranks low in importance across all groups. This study has shown that the preferred HIV program in Viet Nam is feasible, front-loaded for sustainability, has a higher proportion of investment on prevention, saves more lives and prevents more infections. Similarities in government and civil society rankings of criteria can create common grounds for future policy dialogues between stakeholders. Innovative models of planning should be utilized to allow inputs of informed stakeholders at relevant stages of the HIV program planning process.

Do labeled versus unlabeled treatments of alternatives' names influence stated choice outputs? Results from a mode choice study.

PubMed

Jin, Wen; Jiang, Hai; Liu, Yimin; Klampfl, Erica

2017-01-01

Discrete choice experiments have been widely applied to elicit behavioral preferences in the literature. In many of these experiments, the alternatives are named alternatives, meaning that they are naturally associated with specific names. For example, in a mode choice study, the alternatives can be associated with names such as car, taxi, bus, and subway. A fundamental issue that arises in stated choice experiments is whether to treat the alternatives' names as labels (that is, labeled treatment), or as attributes (that is, unlabeled treatment) in the design as well as the presentation phases of the choice sets. In this research, we investigate the impact of labeled versus unlabeled treatments of alternatives' names on the outcome of stated choice experiments, a question that has not been thoroughly investigated in the literature. Using results from a mode choice study, we find that the labeled or the unlabeled treatment of alternatives' names in either the design or the presentation phase of the choice experiment does not statistically affect the estimates of the coefficient parameters. We then proceed to measure the influence toward the willingness-to-pay (WTP) estimates. By using a random-effects model to relate the conditional WTP estimates to the socioeconomic characteristics of the individuals and the labeled versus unlabeled treatments of alternatives' names, we find that: a) Given the treatment of alternatives' names in the presentation phase, the treatment of alternatives' names in the design phase does not statistically affect the estimates of the WTP measures; and b) Given the treatment of alternatives' names in the design phase, the labeled treatment of alternatives' names in the presentation phase causes the corresponding WTP estimates to be slightly higher.

Do labeled versus unlabeled treatments of alternatives’ names influence stated choice outputs? Results from a mode choice study

PubMed Central

Jin, Wen; Jiang, Hai; Liu, Yimin; Klampfl, Erica

2017-01-01

Discrete choice experiments have been widely applied to elicit behavioral preferences in the literature. In many of these experiments, the alternatives are named alternatives, meaning that they are naturally associated with specific names. For example, in a mode choice study, the alternatives can be associated with names such as car, taxi, bus, and subway. A fundamental issue that arises in stated choice experiments is whether to treat the alternatives’ names as labels (that is, labeled treatment), or as attributes (that is, unlabeled treatment) in the design as well as the presentation phases of the choice sets. In this research, we investigate the impact of labeled versus unlabeled treatments of alternatives’ names on the outcome of stated choice experiments, a question that has not been thoroughly investigated in the literature. Using results from a mode choice study, we find that the labeled or the unlabeled treatment of alternatives’ names in either the design or the presentation phase of the choice experiment does not statistically affect the estimates of the coefficient parameters. We then proceed to measure the influence toward the willingness-to-pay (WTP) estimates. By using a random-effects model to relate the conditional WTP estimates to the socioeconomic characteristics of the individuals and the labeled versus unlabeled treatments of alternatives’ names, we find that: a) Given the treatment of alternatives’ names in the presentation phase, the treatment of alternatives’ names in the design phase does not statistically affect the estimates of the WTP measures; and b) Given the treatment of alternatives’ names in the design phase, the labeled treatment of alternatives’ names in the presentation phase causes the corresponding WTP estimates to be slightly higher. PMID:28806764

A Framework for Instrument Development of a Choice Experiment: An Application to Type 2 Diabetes.

PubMed

Janssen, Ellen M; Segal, Jodi B; Bridges, John F P

2016-10-01

Choice experiments are increasingly used to obtain patient preference information for regulatory benefit-risk assessments. Despite the importance of instrument design, there remains a paucity of literature applying good research principles. We applied a novel framework for instrument development of a choice experiment to measure type 2 diabetes mellitus treatment preferences. Applying the framework, we used evidence synthesis, expert consultation, stakeholder engagement, pretest interviews, and pilot testing to develop a best-worst scaling (BWS) and discrete choice experiment (DCE). We synthesized attributes from published DCEs for type 2 diabetes, consulted clinical experts, engaged a national advisory board, conducted local cognitive interviews, and pilot tested a national survey. From published DCEs (n = 17), ten attribute categories were extracted with cost (n = 11) having the highest relative attribute importance (RAI) (range 6-10). Clinical consultation and stakeholder engagement identified six attributes for inclusion. Cognitive pretesting with local diabetes patients (n = 25) ensured comprehension of the choice experiment. Pilot testing with patients from a national sample (n = 50) identified nausea as most important (RAI for DCE: 10 [95 % CI 8.5-11.5]; RAI for BWS: 10 [95 % CI 8.9-11.1]). The developed choice experiment contained five attributes (A1c decrease, blood glucose stability, low blood glucose, nausea, additional medicine, and cost). The framework for instrument development of a choice experiment included five stages of development and incorporated multiple stakeholder perspectives. Further comparisons of instrument development approaches are needed to identify best practices. To facilitate comparisons, researchers need to be encouraged to publish or discuss their instrument development strategies and findings.

A protocol for a discrete choice experiment: understanding preferences of patients with cancer towards their cancer care across metropolitan and rural regions in Australia.

PubMed

Wong, Shu Fen; Norman, Richard; Dunning, Trisha L; Ashley, David M; Lorgelly, Paula K

2014-10-24

Medical decision-making in oncology is a complicated process and to date there are few studies examining how patients with cancer make choices with respect to different features of their care. It is also unknown whether patient choices vary by geographical location and how location could account for observed rural and metropolitan cancer differences. This paper describes an ongoing study that aims to (1) examine patient and healthcare-related factors that influence choices of patients with cancer; (2) measure and quantify preferences of patients with cancer towards cancer care using a discrete choice experiment (DCE) and (3) explore preference heterogeneity between metropolitan and rural locations. A DCE is being conducted to understand how patients with cancer choose between two clinical scenarios accounting for different patient and healthcare-related factors (and levels). Preliminary qualitative research was undertaken to guide the development of an appropriate DCE design including characteristics that are important and relevant to patients with cancer. A fractional factorial design using the D-efficiency criteria was used to estimate interactions among attributes. Multinomial logistic regression will be used for the primary DCE analysis and to control for sociodemographic and clinical characteristics. The Barwon Health Human Research Ethics Committee approved the study. Findings from the study will be presented in national/international conferences and peer-reviewed journals. Our results will form the basis of a feasibility study to inform the development of a larger scale study into preferences of patients with cancer and their association with cancer outcomes. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Consumer preferences for electronic cigarettes: results from a discrete choice experiment.

PubMed

Czoli, Christine D; Goniewicz, Maciej; Islam, Towhidul; Kotnowski, Kathy; Hammond, David

2016-04-01

E-cigarettes present a formidable challenge to regulators given their variety and the rapidly evolving nicotine market. The current study sought to examine the influence of e-cigarette product characteristics on consumer perceptions and trial intentions among Canadians. An online discrete choice experiment was conducted with 915 Canadians aged 16 years and older in November 2013. An online commercial panel was used to sample 3 distinct subpopulations: (1) non-smoking youth and young adults (n=279); (2) smoking youth and young adults (n=264) and (3) smoking adults (n=372). Participants completed a series of stated-preference tasks, in which they viewed choice sets with e-cigarette product images that featured different combinations of attributes: flavour, nicotine content, health warnings and price. For each choice set, participants were asked to select one of the products or indicate 'none of the above' with respect to the following outcomes: interest in trying, less harm and usefulness in quitting smoking. The attributes' impact on consumer choice for each outcome was analysed using multinomial logit regression. Health warning was the most important attribute influencing participants' intentions to try e-cigarettes (42%) and perceived efficacy as a quit aid (39%). Both flavour (36%) and health warnings (35%) significantly predicted perceptions of product harm. The findings indicate that consumers make trade-offs with respect to e-cigarette product characteristics, and that these trade-offs vary across different subpopulations. Given that health warnings and flavour were weighted most important by consumers in this study, these may represent good targets for e-cigarette regulatory frameworks. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

A framework for estimating health state utility values within a discrete choice experiment: modeling risky choices.

PubMed

Robinson, Angela; Spencer, Anne; Moffatt, Peter

2015-04-01

There has been recent interest in using the discrete choice experiment (DCE) method to derive health state utilities for use in quality-adjusted life year (QALY) calculations, but challenges remain. We set out to develop a risk-based DCE approach to derive utility values for health states that allowed 1) utility values to be anchored directly to normal health and death and 2) worse than dead health states to be assessed in the same manner as better than dead states. Furthermore, we set out to estimate alternative models of risky choice within a DCE model. A survey was designed that incorporated a risk-based DCE and a "modified" standard gamble (SG). Health state utility values were elicited for 3 EQ-5D health states assuming "standard" expected utility (EU) preferences. The DCE model was then generalized to allow for rank-dependent expected utility (RDU) preferences, thereby allowing for probability weighting. A convenience sample of 60 students was recruited and data collected in small groups. Under the assumption of "standard" EU preferences, the utility values derived within the DCE corresponded fairly closely to the mean results from the modified SG. Under the assumption of RDU preferences, the utility values estimated are somewhat lower than under the assumption of standard EU, suggesting that the latter may be biased upward. Applying the correct model of risky choice is important whether a modified SG or a risk-based DCE is deployed. It is, however, possible to estimate a probability weighting function within a DCE and estimate "unbiased" utility values directly, which is not possible within a modified SG. We conclude by setting out the relative strengths and weaknesses of the 2 approaches in this context. © The Author(s) 2014.

Evaluation of strategies to communicate harmful and potentially harmful constituent (HPHC) information through cigarette package inserts: a discrete choice experiment.

PubMed

Salloum, Ramzi G; Louviere, Jordan J; Getz, Kayla R; Islam, Farahnaz; Anshari, Dien; Cho, Yoojin; O'Connor, Richard J; Hammond, David; Thrasher, James F

2017-07-13

The US Food and Drug Administration (FDA) has regulatory authority to use inserts to communicate with consumers about harmful and potentially harmful constituents (HPHCs) in tobacco products; however, little is known about the most effective manner for presenting HPHC information. In a discrete choice experiment, participants evaluated eight choice sets, each of which showed two cigarette packages from four different brands and tar levels (high vs low), accompanied by an insert that included between-subject manipulations (ie, listing of HPHCs vs grouping by disease outcome and numeric values ascribed to HPHCs vs no numbers) and within-subject manipulations (ie, 1 of 4 warning topics; statement linking an HPHC with disease vs statement with no HPHC link). For each choice set, participants were asked: (1) which package is more harmful and (2) which motivates them to not smoke; each with a 'no difference' option. Alternative-specific logit models regressed choice on attribute levels. 1212 participants were recruited from an online consumer panel (725 18-29-year-old smokers and susceptible non-smokers and 487 30-64-year-old smokers). Participants were more likely to endorse high-tar products as more harmful than low-tar products, with a greater effect when numeric HPHC information was present. Compared with a simple warning statement, the statement linking HPHCs with disease encouraged quit motivation. Numeric HPHC information on inserts appears to produce misunderstandings that some cigarettes are less harmful than others. Furthermore, brief narratives that link HPHCs to smoking-related disease may promote cessation versus communications that do not explicitly link HPHCs to disease. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Divergent Preferences for HIV Prevention: A Discrete Choice Experiment for Multipurpose HIV Prevention Products in South Africa.

PubMed

Quaife, Matthew; Eakle, Robyn; Cabrera Escobar, Maria A; Vickerman, Peter; Kilbourne-Brook, Maggie; Mvundura, Mercy; Delany-Moretlwe, Sinead; Terris-Prestholt, Fern

2018-01-01

The development of antiretroviral (ARV)-based prevention products has the potential to substantially change the HIV prevention landscape; yet, little is known about how appealing these products will be outside of clinical trials, as compared with the existing options. We conducted a discrete choice experiment (DCE) to measure preferences for 5 new products among 4 important populations in the HIV response: adult men and women in the general population (aged 18 to 49 y), adolescent girls (aged 16 to 17 y), and self-identifying female sex workers (aged 18 to 49 y). We interviewed 661 self-reported HIV-negative participants in peri-urban South Africa, who were asked to choose between 3 unique, hypothetical products over 10 choice sets. Data were analyzed using multinomial, latent class and mixed multinomial logit models. HIV protection was the most important attribute to respondents; however, results indicate significant demand among all groups for multipurpose prevention products that offer protection from HIV infection, other STIs, and unwanted pregnancy. All groups demonstrated a strong preference for long-lasting injectable products. There was substantial heterogeneity in preferences within and across population groups. Hypothetical DCE data may not mirror real-world choices, and products will have more attributes in reality than represented in choice tasks. Background data on participants, including sensitive areas of HIV status and condom use, was self-reported. These results suggest that stimulating demand for new HIV prevention products may require a more a nuanced approach than simply developing highly effective products. No single product is likely to be equally attractive or acceptable across different groups. This study strengthens the call for effective and attractive multipurpose prevention products to be deployed as part of a comprehensive combination prevention strategy.

Choice Experiments to Quantify Preferences for Health and Healthcare: State of the Practice.

PubMed

Mühlbacher, Axel; Johnson, F Reed

2016-06-01

Stated-preference methods increasingly are used to quantify preferences in health economics, health technology assessment, benefit-risk analysis and health services research. The objective of stated-preference studies is to acquire information about trade-off preferences among treatment outcomes, prioritization of clinical decision criteria, likely uptake or adherence to healthcare products and acceptability of healthcare services or policies. A widely accepted approach to eliciting preferences is discrete-choice experiments. Patient, physician, insurant or general-public respondents choose among constructed, experimentally controlled alternatives described by decision-relevant features or attributes. Attributes can represent complete health states, sets of treatment outcomes or characteristics of a healthcare system. The observed pattern of choice reveals how different respondents or groups of respondents implicitly weigh, value and assess different characteristics of treatments, products or services. An important advantage of choice experiments is their foundation in microeconomic utility theory. This conceptual framework provides tests of internal validity, guidance for statistical analysis of latent preference structures, and testable behavioural hypotheses. Choice experiments require expertise in survey-research methods, random-utility theory, experimental design and advanced statistical analysis. This paper should be understood as an introduction to setting up a basic experiment rather than an exhaustive critique of the latest findings and procedures. Where appropriate, we have identified topics of active research where a broad consensus has not yet been established.

How to value protection from natural hazards - a step-by-step discrete choice approach

NASA Astrophysics Data System (ADS)

Olschewski, R.

2013-04-01

In mountainous regions, forests play a crucial role in protecting the local population from natural hazards. In cases where existing forests are destroyed, e.g. by wind throws or diseases, the protection function has to be restored through technical measures. To determine the willingness to pay (WTP) for protection against avalanches, a choice experiment has been conducted and different experiment specifications have been tested to determine possible impacts on the results. The present study contributes to a comprehensive assessment of protection measures, and helps to identify efficient solutions based on the judgement of the people potentially endangered by natural hazards. The stepwise approach has the advantage to gradually check data fit, thereby didactically showing an operational way of dealing with different model specifications. The detailed case study can serve as a manual for conducting choice experiments with a similar focus and demonstrates the suitability and caveats of this approach to value protection from natural hazards in general.

Tell me once, tell me soon: parents' preferences for clinical genetics services for congenital heart disease.

PubMed

Kasparian, Nadine A; De Abreu Lourenco, Richard; Winlaw, David S; Sholler, Gary F; Viney, Rosalie; Kirk, Edwin P E

2018-03-01

PurposeAs the molecular basis of congenital heart disease (CHD) comes into sharper focus, cardiac genetics services are likely to play an increasingly important role. This study aimed to identify parents' preferences for, and willingness to participate in, clinical genetics services for CHD.MethodsA discrete choice experiment was developed to assess parents' preferences for pediatric cardiogenetics services based on four attributes: appointment format, health professionals involved, waiting time, and information format. Data were analyzed using a mixed logit model.ResultsOne hundred parents with a living child diagnosed with CHD requiring surgical intervention between 2000 and 2009 completed the discrete choice experiment. Parents expressed a clear preference for cardiac genetics services featuring (i) a single appointment, (ii) the presence of a clinical geneticist and a genetic counselor, (iii) both verbal (oral) and Web-based information about CHD and genetics, and (iv) availability of an appointment within 2 weeks. If offered such conditions, 93% of respondents indicated that they would attend. The choice of service was most strongly influenced by the presence of both a clinical geneticist and a genetic counselor.ConclusionParents of children with CHD favor a single, timely genetics appointment with both a geneticist and a genetic counselor present. If appointments offered match these preferences, uptake is likely to be high.Genet Med advance online publication, 1 March 2018; doi:10.1038/gim.2018.16.

Discrete choice experiment produced estimates of acceptable risks of therapeutic options in cancer patients with febrile neutropenia.

PubMed

Sung, Lillian; Alibhai, Shabbir M; Ethier, Marie-Chantal; Teuffel, Oliver; Cheng, Sylvia; Fisman, David; Regier, Dean A

2012-06-01

To use a discrete choice experiment (DCE) to describe patient/proxy tolerance for the number of clinic visits, and chances of readmission, intensive care unit admission, and mortality to accept oral outpatient management of low-risk febrile neutropenia. Adults and children aged 12-18 years with cancer and parents of pediatric cancer patients were asked to choose between outpatient oral and inpatient intravenous management of low-risk febrile neutropenia. Using a DCE, we varied the attribute levels with the outpatient option and kept them constant for the inpatient option. Seventy-eight adults, 153 parents, and 43 children provided responses. All four attributes significantly affected choices. The mean tolerance (95% confidence interval) for the number of clinic visits per week was 3.6 (2.2-4.8), 2.1 (1.1-3.2), and 4.3 (2.5-6.0) to accept outpatient management among adults, parents, and children, respectively. With thrice weekly clinic visits and 7.5% chance of readmission, probabilities of accepting the outpatient strategy were 50% (44-54%) for adults, 43% (39-48%) for parents, and 53% (46-59%) for children. Using a DCE, we determined that a 7.5% chance of readmission and clinic visits more frequently than thrice weekly are unlikely to be acceptable. Copyright © 2012 Elsevier Inc. All rights reserved.

Women’s Preferences for Treatment of Perinatal Depression and Anxiety: A Discrete Choice Experiment

PubMed Central

Ride, Jemimah; Lancsar, Emily

2016-01-01

Perinatal depression and anxiety (PNDA) are an international healthcare priority, associated with significant short- and long-term problems for women, their children and families. Effective treatment is available but uptake is suboptimal: some women go untreated whilst others choose treatments without strong evidence of efficacy. Better understanding of women’s preferences for treatment is needed to facilitate uptake of effective treatment. To address this issue, a discrete choice experiment (DCE) was administered to 217 pregnant or postnatal women in Australia, who were recruited through an online research company and had similar sociodemographic characteristics to Australian data for perinatal women. The DCE investigated preferences regarding cost, treatment type, availability of childcare, modality and efficacy. Data were analysed using logit-based models accounting for preference and scale heterogeneity. Predicted probability analysis was used to explore relative attribute importance and policy change scenarios, including how these differed by women’s sociodemographic characteristics. Cost and treatment type had the greatest impact on choice, such that a policy of subsidising effective treatments was predicted to double their uptake compared with the base case. There were differences in predicted uptake associated with certain sociodemographic characteristics: for example, women with higher educational attainment were more likely to choose effective treatment. The findings suggest policy directions for decision makers whose goal is to reduce the burden of PNDA on women, their children and families. PMID:27258096

Women's Preferences for Treatment of Perinatal Depression and Anxiety: A Discrete Choice Experiment.

PubMed

Ride, Jemimah; Lancsar, Emily

2016-01-01

Perinatal depression and anxiety (PNDA) are an international healthcare priority, associated with significant short- and long-term problems for women, their children and families. Effective treatment is available but uptake is suboptimal: some women go untreated whilst others choose treatments without strong evidence of efficacy. Better understanding of women's preferences for treatment is needed to facilitate uptake of effective treatment. To address this issue, a discrete choice experiment (DCE) was administered to 217 pregnant or postnatal women in Australia, who were recruited through an online research company and had similar sociodemographic characteristics to Australian data for perinatal women. The DCE investigated preferences regarding cost, treatment type, availability of childcare, modality and efficacy. Data were analysed using logit-based models accounting for preference and scale heterogeneity. Predicted probability analysis was used to explore relative attribute importance and policy change scenarios, including how these differed by women's sociodemographic characteristics. Cost and treatment type had the greatest impact on choice, such that a policy of subsidising effective treatments was predicted to double their uptake compared with the base case. There were differences in predicted uptake associated with certain sociodemographic characteristics: for example, women with higher educational attainment were more likely to choose effective treatment. The findings suggest policy directions for decision makers whose goal is to reduce the burden of PNDA on women, their children and families.

Non-Market Values in a Cost-Benefit World: Evidence from a Choice Experiment.

PubMed

Eppink, Florian V; Winden, Matthew; Wright, Will C C; Greenhalgh, Suzie

2016-01-01

In support of natural resource and ecosystem service policy, monetary value estimates are often presented to decision makers along with other types of information. There is some evidence that, presented with such 'mixed' information, people prioritise monetary over non-monetary information. We conduct a discrete choice experiment among New Zealand decision makers in which we manipulate the information presented to participants. We find that providing explicit monetary information strengthens the pursuit of economic benefits as well as the avoidance of environmental damage. Cultural impacts, of which we provided only qualitative descriptions, did not affect respondents' choices. Our study provides further evidence that concerns regarding the use of monetary information in decisions with complex, multi-value impacts are valid. Further research is needed to validate our results and find ways to reduce any bias in monetary and non-market information.

Non-Market Values in a Cost-Benefit World: Evidence from a Choice Experiment

PubMed Central

Eppink, Florian V.; Winden, Matthew; Wright, Will C. C.; Greenhalgh, Suzie

2016-01-01

In support of natural resource and ecosystem service policy, monetary value estimates are often presented to decision makers along with other types of information. There is some evidence that, presented with such ‘mixed’ information, people prioritise monetary over non-monetary information. We conduct a discrete choice experiment among New Zealand decision makers in which we manipulate the information presented to participants. We find that providing explicit monetary information strengthens the pursuit of economic benefits as well as the avoidance of environmental damage. Cultural impacts, of which we provided only qualitative descriptions, did not affect respondents’ choices. Our study provides further evidence that concerns regarding the use of monetary information in decisions with complex, multi-value impacts are valid. Further research is needed to validate our results and find ways to reduce any bias in monetary and non-market information. PMID:27783657

Discrete-choice experiment to measure patient preferences for the surgical management of colorectal cancer.

PubMed

Salkeld, G; Solomon, M; Butow, P; Short, L

2005-06-01

Establishing trust between a patient and his or her surgeon is of paramount importance. The aim of this study was to assess the relative importance of the 'attributes of trust' between surgeon and patient with colorectal cancer. A discrete-choice questionnaire was conducted with 60 men and 43 women who had completed primary treatment for colorectal cancer in two teaching hospitals in Sydney, Australia. Forty-seven of the 103 patients based their choice of surgical management on a single attribute and the remainder were willing to trade between different attributes. In order of importance, patients based their choice of surgical management on specialty training (beta coefficient = 0.83), surgeon's communication (beta = 0.82), type of hospital (beta = 0.72) and who decides treatment (beta = 0.01). Patients who were vigilant in their decision-making style and those who did not have tertiary education were more likely to change their preferences in the repeat interview. Clinicians may have a better chance of meeting a patient's expectations about the process of care if they assess the patient's desire for knowledge and give those who do not have tertiary education more time to assimilate information about their treatment. Copyright (c) 2005 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd.

MCDA swing weighting and discrete choice experiments for elicitation of patient benefit-risk preferences: a critical assessment.

PubMed

Tervonen, Tommi; Gelhorn, Heather; Sri Bhashyam, Sumitra; Poon, Jiat-Ling; Gries, Katharine S; Rentz, Anne; Marsh, Kevin

2017-12-01

Multiple criteria decision analysis swing weighting (SW) and discrete choice experiments (DCE) are appropriate methods for capturing patient preferences on treatment benefit-risk trade-offs. This paper presents a qualitative comparison of the 2 methods. We review and critically assess similarities and differences of SW and DCE based on 6 aspects: comprehension by study participants, cognitive biases, sample representativeness, ability to capture heterogeneity in preferences, reliability and validity, and robustness of the results. The SW choice task can be more difficult, but the workshop context in which SW is conducted may provide more support to patients who are unfamiliar with the end points being evaluated or who have cognitive impairments. Both methods are similarly prone to a number of biases associated with preference elicitation, and DCE is prone to simplifying heuristics, which limits its application with large number of attributes. The low cost per patient of the DCE means that it can be better at achieving a representative sample, though SW does not require such large sample sizes due to exact nature of the collected preference data. This also means that internal validity is automatically enforced with SW, while the internal validity of DCE results needs to be assessed manually. Choice between the 2 methods depends on characteristics of the benefit-risk assessment, especially on how difficult the trade-offs are for the patients to make and how many patients are available. Although there exist some empirical studies on many of the evaluation aspects, critical evidence gaps remain. Copyright © 2017 John Wiley & Sons, Ltd.

Understanding the relative valuation of research impact: a best–worst scaling experiment of the general public and biomedical and health researchers

PubMed Central

Pollitt, Alexandra; Potoglou, Dimitris; Patil, Sunil; Burge, Peter; Guthrie, Susan; King, Suzanne; Wooding, Steven; Grant, Jonathan

2016-01-01

Objectives (1) To test the use of best–worst scaling (BWS) experiments in valuing different types of biomedical and health research impact, and (2) to explore how different types of research impact are valued by different stakeholder groups. Design Survey-based BWS experiment and discrete choice modelling. Setting The UK. Participants Current and recent UK Medical Research Council grant holders and a representative sample of the general public recruited from an online panel. Results In relation to the study's 2 objectives: (1) we demonstrate the application of BWS methodology in the quantitative assessment and valuation of research impact. (2) The general public and researchers provided similar valuations for research impacts such as improved life expectancy, job creation and reduced health costs, but there was less agreement between the groups on other impacts, including commercial capacity development, training and dissemination. Conclusions This is the second time that a discrete choice experiment has been used to assess how the general public and researchers value different types of research impact, and the first time that BWS has been used to elicit these choices. While the 2 groups value different research impacts in different ways, we note that where they agree, this is generally about matters that are seemingly more important and associated with wider social benefit, rather than impacts occurring within the research system. These findings are a first step in exploring how the beneficiaries and producers of research value different kinds of impact, an important consideration given the growing emphasis on funding and assessing research on the basis of (potential) impact. Future research should refine and replicate both the current study and that of Miller et al in other countries and disciplines. PMID:27540096

Women's preferences for obstetric care in rural Ethiopia: a population-based discrete choice experiment in a region with low rates of facility delivery.

PubMed

Kruk, M E; Paczkowski, M M; Tegegn, A; Tessema, F; Hadley, C; Asefa, M; Galea, S

2010-11-01

Delivery attended by skilled professionals is essential to reducing maternal mortality. Although the facility delivery rate in Ethiopia's rural areas is extremely low, little is known about which health system characteristics most influence women's preferences for delivery services. In this study, women's preferences for attributes of health facilities for delivery in rural Ethiopia were investigated. A population-based discrete choice experiment (DCE) was fielded in Gilgel Gibe, in southwest Ethiopia, among women with a delivery in the past 5 years. Women were asked to select a hypothetical health facility for future delivery from two facilities on a picture card. A hierarchical Bayesian procedure was used to estimate utilities associated with facility attributes: distance, type of provider, provider attitude, drugs and medical equipment, transport and cost. 1006 women completed 8045 DCE choice tasks. Among them, 93.8% had delivered their last child at home. The attributes with the greatest influence on the overall utility of a health facility for delivery were availability of drugs and equipment (mean β=3.9, p<0.01), seeing a doctor versus a health extension worker (mean β=2.1, p<0.01) and a receptive provider attitude (mean β=1.4, p<0.01). Women in rural southwest Ethiopia who have limited personal experience with facility delivery nonetheless value health facility attributes that indicate high technical quality: availability of drugs and equipment and physician providers. Well-designed policy experiments that measure the contribution of quality improvements to facility delivery rates in Ethiopia and other countries with low health service utilisation and high maternal mortality may inform national efforts to reduce maternal mortality.

WHAT IS THE ROLE OF COMMUNITY PREFERENCE INFORMATION IN HEALTH TECHNOLOGY ASSESSMENT DECISION MAKING? A CASE STUDY OF COLORECTAL CANCER SCREENING.

PubMed

Wortley, Sally; Flitcroft, Kathy; Howard, Kirsten

2015-01-01

The aim of this study was to determine the role of community preference information from discrete choice studies of colorectal cancer (CRC) screening in health technology assessment (HTA) reports and subsequent policy decisions. We undertook a systematic review of discrete choice studies of CRC screening. Included studies were reviewed to assess the policy context of the research. For those studies that cited a recent or pending review of CRC screening, further searches were undertaken to determine the extent to which community preference information was incorporated into the HTA decision-making process. Eight discrete choice studies that evaluated preferences for CRC screening were identified. Four of these studies referred to a national or local review of CRC screening in three countries: Australia, Canada, and the Netherlands. Our review of subsequently released health policy documents showed that while consideration was given to community views on CRC, policy was not informed by discrete choice evidence. Preferences and values of patients are increasingly being considered "evidence" to be incorporated into HTA reports. Discrete choice methodology is a rigorous quantitative method for eliciting preferences and while as a methodology it is growing in profile, it would appear that the results of such research are not being systematically translated or integrated into HTA reports. A formalized approach is needed to incorporate preference literature into the HTA decision-making process.

Priority setting in the Austrian healthcare system: results from a discrete choice experiment and implications for mental health.

PubMed

Mentzakis, Emmanouil; Paolucci, Francesco; Rubicko, Georg

2014-06-01

The impact of mental conditions is expected to be among the highest ranked causes of illness in high income countries by 2020. With changing health needs, policy makers have to make choices in an environment with increasingly constrained resources and competing demands. Discrete choice experiments have been identified as a useful approach to inform and support decision-making in health care systems and, in particular, its rationing. Policymakers, researchers and health practitioners from Austria participated in an experiment designed to elicit preferences for efficiency and equity in a generic priority setting framework. Using aggregate criteria an empirical measure of the efficiency/equity trade-off is calculated and a selection of health care interventions, including mental health, are ranked in composite league tables (CLTs). With the exception of severity of the condition, all equity parameters decrease attractiveness of an intervention, whereas the opposite holds for all three efficiency criteria. The efficiency/equity ratio (i.e. decision-makers' preference for efficiency over equity) is 3.5 and 5 for interventions targeted at younger and middle age populations, respectively, while for older populations this ratio is negative implying a rejection of all equity criteria. Irrespective of such differences interventions targeting mental health rank highly on all CLTs. Based on system-wide generic decision making criteria, mental health is shown to be a top priority for Austria. Preference-based approaches might offer complementary information to policymakers in priority setting decisions and a useful tool to support rationale rather than ad hoc decision-making.

Should flavours be banned in cigarettes and e-cigarettes? Evidence on adult smokers and recent quitters from a discrete choice experiment.

PubMed

Buckell, John; Marti, Joachim; Sindelar, Jody L

2018-05-28

To provide the policy-relevant estimates of impacts of alternative flavour bans on preferences and demand for cigarettes and e-cigarettes in adult smokers and recent quitters. A best-best discrete choice experiment (DCE) is used to elicit smokers' and recent quitters' preferences for flavours, price, health impact and nicotine level in cigarettes and e-cigarettes. Choice of tobacco products and an opt-out option were examined. An efficient design yielded 36 choice sets. Exploded logit choice models were estimated. Flavour bans are modelled by restricting flavour coefficients in the estimated model. A sample of 2031 adult smokers and recent quitters was recruited to complete an online survey and DCE. Current smokers and recent quitters, on average, prefer cigarettes and menthol cigarettes over flavoured e-cigarettes. However, there is substantial preference heterogeneity by younger adults (ages 18-25), race/ethnicity and respondents with higher education. Our predictions suggest that a ban on menthol cigarettes would produce the greatest reduction in the choice of cigarettes (-5.2%), but with an accompanying increase in e-cigarettes use (3.8%). In contrast, banning flavours in e-cigarettes, while allowing menthol in cigarettes would result in the greatest increase in the selection of cigarettes (8.3%), and a decline in the use of e-cigarettes (-11.1%). A ban on all flavours, but tobacco in both products would increase 'opting-out' the most (5.2%) but would also increase choice of cigarettes (2.7%) and decrease choice of e-cigarettes (-7.9%). A ban on flavoured e-cigarettes alone would likely increase the choice of cigarettes in smokers, arguably the more harmful way of obtaining nicotine, whereas a ban on menthol cigarettes alone would likely be more effective in reducing the choice of cigarettes. A ban on all flavours in both products would likely reduce the smoking/vaping rates, but the use of cigarettes would be higher than in the status quo. Policy-makers should use these results to guide the choice of flavour bans in light of their stance on the potential health impacts both products. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

A likelihood-based biostatistical model for analyzing consumer movement in simultaneous choice experiments.

PubMed

Zeilinger, Adam R; Olson, Dawn M; Andow, David A

2014-08-01

Consumer feeding preference among resource choices has critical implications for basic ecological and evolutionary processes, and can be highly relevant to applied problems such as ecological risk assessment and invasion biology. Within consumer choice experiments, also known as feeding preference or cafeteria experiments, measures of relative consumption and measures of consumer movement can provide distinct and complementary insights into the strength, causes, and consequences of preference. Despite the distinct value of inferring preference from measures of consumer movement, rigorous and biologically relevant analytical methods are lacking. We describe a simple, likelihood-based, biostatistical model for analyzing the transient dynamics of consumer movement in a paired-choice experiment. With experimental data consisting of repeated discrete measures of consumer location, the model can be used to estimate constant consumer attraction and leaving rates for two food choices, and differences in choice-specific attraction and leaving rates can be tested using model selection. The model enables calculation of transient and equilibrial probabilities of consumer-resource association, which could be incorporated into larger scale movement models. We explore the effect of experimental design on parameter estimation through stochastic simulation and describe methods to check that data meet model assumptions. Using a dataset of modest sample size, we illustrate the use of the model to draw inferences on consumer preference as well as underlying behavioral mechanisms. Finally, we include a user's guide and computer code scripts in R to facilitate use of the model by other researchers.

Eliciting preferences for priority setting in genetic testing: a pilot study comparing best-worst scaling and discrete-choice experiments.

PubMed

Severin, Franziska; Schmidtke, Jörg; Mühlbacher, Axel; Rogowski, Wolf H

2013-11-01

Given the increasing number of genetic tests available, decisions have to be made on how to allocate limited health-care resources to them. Different criteria have been proposed to guide priority setting. However, their relative importance is unclear. Discrete-choice experiments (DCEs) and best-worst scaling experiments (BWSs) are methods used to identify and weight various criteria that influence orders of priority. This study tests whether these preference eliciting techniques can be used for prioritising genetic tests and compares the empirical findings resulting from these two approaches. Pilot DCE and BWS questionnaires were developed for the same criteria: prevalence, severity, clinical utility, alternatives to genetic testing available, infrastructure for testing and care established, and urgency of care. Interview-style experiments were carried out among different genetics professionals (mainly clinical geneticists, researchers and biologists). A total of 31 respondents completed the DCE and 26 completed the BWS experiment. Weights for the levels of the six attributes were estimated by conditional logit models. Although the results derived from the DCE and BWS experiments differed in detail, we found similar valuation patterns in the DCE and BWS experiments. The respondents attached greatest value to tests with high clinical utility (defined by the availability of treatments that reduce mortality and morbidity) and to testing for highly prevalent conditions. The findings from this study exemplify how decision makers can use quantitative preference eliciting methods to measure aggregated preferences in order to prioritise alternative clinical interventions. Further research is necessary to confirm the survey results.

Modeling the Problem-Based Learning Preferences of McMaster University Undergraduate Medical Students Using a Discrete Choice Conjoint Experiment

ERIC Educational Resources Information Center

Cunningham, Charles E.; Deal, Ken; Neville, Alan; Rimas, Heather; Lohfeld, Lynne

2006-01-01

Objectives: To use methods from the field of marketing research to involve students in the redesign of McMaster University's small group, problem-based undergraduate medical education program. Methods: We used themes from a focus group conducted in an electronic decision support lab to compose 14 four-level educational attributes. Undergraduate…

Patient and health professional preferences for organ allocation and procurement, end-of-life care and organization of care for patients with chronic kidney disease using a discrete choice experiment.

PubMed

Davison, Sara N; Kromm, Seija K; Currie, Gillian R

2010-07-01

Clinical practice, policy and research, and the ethical bases upon which they are founded, should be systematically and transparently informed by both patient and professional values. A discrete choice experiment was utilized to understand and quantify the preferences of 351 Canadian patients and healthcare providers in relation to ethically challenging aspects of the management of chronic kidney disease (CKD): procurement and allocation of organs for transplantation, end-of-life care discussions and decision making and the identities of those providing primary care. Patients and health professionals had clear preferences for detailed prognostic information, early advance care planning, shared end-of-life decision making, coordinated models of care that enhance interaction and communication between primary and tertiary care and a more utilitarian approach of best match over first come, first served for allocating deceased donor kidneys. These data also suggest that the innovative strategies of non-directed anonymous donation and paired kidney exchange that are slowly being implemented internationally will be acceptable to both patients and healthcare providers. Current models of CKD care do not consistently reflect the preferences or priorities of either health professionals or patients.

Rationalising the 'irrational': a think aloud study of discrete choice experiment responses.

PubMed

Ryan, Mandy; Watson, Verity; Entwistle, Vikki

2009-03-01

Stated preference methods assume respondents' preferences are consistent with utility theory, but many empirical studies report evidence of preferences that violate utility theory. This evidence is often derived from quantitative tests that occur naturally within, or are added to, stated preference tasks. In this study, we use qualitative methods to explore three axioms of utility theory: completeness, monotonicity, and continuity. We take a novel approach, adopting a 'think aloud' technique to identify violations of the axioms of utility theory and to consider how well the quantitative tests incorporated within a discrete choice experiment are able to detect these. Results indicate that quantitative tests classify respondents as being 'irrational' when qualitative statements would indicate they are 'rational'. In particular, 'non-monotonic' responses can often be explained by respondents inferring additional information beyond what is presented in the task, and individuals who appear to adopt non-compensatory decision-making strategies do so because they rate particular attributes very highly (they are not attempting to simplify the task). The results also provide evidence of 'cost-based responses': respondents assumed tests with higher costs would be of higher quality. The value of including in-depth qualitative validation techniques in the development of stated preference tasks is shown.

Is Best-Worst Scaling Suitable for Health State Valuation? A Comparison with Discrete Choice Experiments.

PubMed

Krucien, Nicolas; Watson, Verity; Ryan, Mandy

2017-12-01

Health utility indices (HUIs) are widely used in economic evaluation. The best-worst scaling (BWS) method is being used to value dimensions of HUIs. However, little is known about the properties of this method. This paper investigates the validity of the BWS method to develop HUI, comparing it to another ordinal valuation method, the discrete choice experiment (DCE). Using a parametric approach, we find a low level of concordance between the two methods, with evidence of preference reversals. BWS responses are subject to decision biases, with significant effects on individuals' preferences. Non parametric tests indicate that BWS data has lower stability, monotonicity and continuity compared to DCE data, suggesting that the BWS provides lower quality data. As a consequence, for both theoretical and technical reasons, practitioners should be cautious both about using the BWS method to measure health-related preferences, and using HUI based on BWS data. Given existing evidence, it seems that the DCE method is a better method, at least because its limitations (and measurement properties) have been extensively researched. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Discrete choice experiment of smoking cessation behaviour in Japan

PubMed Central

Goto, Rei; Nishimura, Shuzo; Ida, Takanori

2007-01-01

Background In spite of gradual increases in tobacco price and the introduction of laws supporting various anti‐tobacco measures, the proportion of smokers in Japan's population is still higher than in other developed nations. Objective To understand what information and individual characteristics drive smokers to attempt to quit smoking. These determinants will help to realise effective tobacco control policy as a base for understanding of cessation behaviour. Method Discrete choice experiments on a total of 616 respondents registered at a consumer monitoring investigative company. Results The effect of price is greater on smokers with lower nicotine dependence. For smokers of moderate and low dependency, short term health risks and health risks caused by passive smoking have a strong impact, though the existence of penalties and long term health risks have little influence on smokers' decisions to quit. For highly dependent smokers, non‐price attributes have little impact. Furthermore, the effects of age, sex and knowledge are also not uniform in accounting for smoking cessation. Conclusion Determinants of smoking cessation vary among levels of nicotine dependency. Therefore, how and what information is provided needs to be carefully considered when counselling smokers to help them to quit. PMID:17897993

Discretization of 3d gravity in different polarizations

NASA Astrophysics Data System (ADS)

Dupuis, Maïté; Freidel, Laurent; Girelli, Florian

2017-10-01

We study the discretization of three-dimensional gravity with Λ =0 following the loop quantum gravity framework. In the process, we realize that different choices of polarization are possible. This allows us to introduce a new discretization based on the triad as opposed to the connection as in the standard loop quantum gravity framework. We also identify the classical nontrivial symmetries of discrete gravity, namely the Drinfeld double, given in terms of momentum maps. Another choice of polarization is given by the Chern-Simons formulation of gravity. Our framework also provides a new discretization scheme of Chern-Simons, which keeps track of the link between the continuum variables and the discrete ones. We show how the Poisson bracket we recover between the Chern-Simons holonomies allows us to recover the Goldman bracket. There is also a transparent link between the discrete Chern-Simons formulation and the discretization of gravity based on the connection (loop gravity) or triad variables (dual loop gravity).

Design and analysis of simple choice surveys for natural resource management

USGS Publications Warehouse

Fieberg, John; Cornicelli, Louis; Fulton, David C.; Grund, Marrett D.

2010-01-01

We used a simple yet powerful method for judging public support for management actions from randomized surveys. We asked respondents to rank choices (representing management regulations under consideration) according to their preference, and we then used discrete choice models to estimate probability of choosing among options (conditional on the set of options presented to respondents). Because choices may share similar unmodeled characteristics, the multinomial logit model, commonly applied to discrete choice data, may not be appropriate. We introduced the nested logit model, which offers a simple approach for incorporating correlation among choices. This forced choice survey approach provides a useful method of gathering public input; it is relatively easy to apply in practice, and the data are likely to be more informative than asking constituents to rate attractiveness of each option separately.

Discrete-choice modelling of patient preferences for modes of drug administration.

PubMed

Tetteh, Ebenezer Kwabena; Morris, Steve; Titcheneker-Hooker, Nigel

2017-12-01

The administration of (biologically-derived) drugs for various disease conditions involves consumption of resources that constitutes a direct monetary cost to healthcare payers and providers. An often ignored cost relates to a mismatch between patients' preferences and the mode of drug administration. The "intangible" benefits of giving patients what they want in terms of the mode of drug delivery is seldom considered. This study aims to evaluate, in monetary terms, end-user preferences for the non-monetary attributes of different modes of drug administration using a discrete-choice experiment. It provides empirical support to the notion that there are significant benefits from developing patient-friendly approaches to drug delivery. The gross benefits per patient per unit administration is in the same order of magnitude as the savings in resource costs of administering drugs. The study argues that, as long as the underlying manufacturing science is capable, a patient-centred approach to producing drug delivery systems should be encouraged and pursued.

Examining Parents’ Preferences for Group and Individual Parent Training For Children with ADHD Symptoms

PubMed Central

Wymbs, Frances A.; Cunningham, Charles E.; Chen, Yvonne; Rimas, Heather M.; Deal, Ken; Waschbusch, Daniel A.; Pelham, William E.

2015-01-01

Parent training (PT) programs have been found to reduce some behavioral impairment associated with children’s attention deficit hyperactivity disorder (ADHD) as well as improve parenting competence, but poor uptake and participation by parents are formidable barriers that affect service effectiveness. We used a discrete choice experiment (DCE) to examine how parent preferences for treatment format (i.e. group versus individual) might influence their participation in PT. Participants were 445 parents seeking mental health services for children with elevated symptoms of ADHD in Ontario, Canada. Parents completed a discrete-choice experiment (DCE) composed of 30 choice tasks used to gauge PT format preference. Results showed that 58.7% of parents preferred individual PT; these parents were most interested in interventions that would make them feel more informed about their child’s problems and in understanding—as opposed to solving—their child’s problems. A minority of parents (19.4 %) preferred group PT; these parents were most interested in active, skill-building services that would help them solve their child’s problems. About one-fifth of parents (21.9 %) preferred the Minimal Information alternative (i.e. receiving neither individual or group PT); these parents reported the highest levels of depression and the most severe mental health problems in their child. Results highlight the importance of considering parent preferences for format, and suggest that alternative formats to standard PT should be considered for multiply stressed families. PMID:25700219

Video or In-Clinic Consultation? Selection of Attributes as Preparation for a Discrete Choice Experiment Among Key Stakeholders.

PubMed

Chudner, Irit; Goldfracht, Margalit; Goldblatt, Hadass; Drach-Zahavy, Anat; Karkabi, Khaled

2018-06-09

Video consultations (VCs) provide increased accessibility of primary care to remote areas and overall improved care for chronic patients. They also contribute to higher patient satisfaction and improved resource management. Despite these benefits, VC integration into the health system is complex and slow. Understanding the VC-related preferences of three key stakeholders-patients, primary care physicians (PCPs) and policy makers (PMs)-is crucial for achieving optimal implementation. The aim of this study was to select relevant attributes and levels for a discrete choice experiment (DCE) of stakeholders' choice-VC or traditional in-clinic consultation (I-CC) in primary care. Ten semi-structured focus group interviews and 24 semi-structured individual interviews were conducted. Data analysis was performed inductively, using a thematic content analysis method. An attribute-ranking exercise was then conducted based on the results gleaned from the interviews. The most important attributes when choosing either VC or I-CC, for both patients and PMs, were: (1) time to next available appointment; (2) time in line before consultation; (3) relationship to PCP; and (4) quality of consultation. For PCPs, the most important attributes were: (1) time in line before consultation; (2) patient's self-management ability; (3) consultation purpose; (4) quality of consultation. This qualitative study identified attributes and levels for a DCE quantitative stage among three key stakeholder groups. It adds to the literature of examples of developing DCE attributes, and to literature about the stakeholder benefits in the area of telemedicine in healthcare.

Societal preferences for distributive justice in the allocation of health care resources: a latent class discrete choice experiment.

PubMed

Skedgel, Chris; Wailoo, Allan; Akehurst, Ron

2015-01-01

Economic theory suggests that resources should be allocated in a way that produces the greatest outputs, on the grounds that maximizing output allows for a redistribution that could benefit everyone. In health care, this is known as QALY (quality-adjusted life-year) maximization. This justification for QALY maximization may not hold, though, as it is difficult to reallocate health. Therefore, the allocation of health care should be seen as a matter of distributive justice as well as efficiency. A discrete choice experiment was undertaken to test consistency with the principles of QALY maximization and to quantify the willingness to trade life-year gains for distributive justice. An empirical ethics process was used to identify attributes that appeared relevant and ethically justified: patient age, severity (decomposed into initial quality and life expectancy), final health state, duration of benefit, and distributional concerns. Only 3% of respondents maximized QALYs with every choice, but scenarios with larger aggregate QALY gains were chosen more often and a majority of respondents maximized QALYs in a majority of their choices. However, respondents also appeared willing to prioritize smaller gains to preferred groups over larger gains to less preferred groups. Marginal analyses found a statistically significant preference for younger patients and a wider distribution of gains, as well as an aversion to patients with the shortest life expectancy or a poor final health state. These results support the existence of an equity-efficiency tradeoff and suggest that well-being could be enhanced by giving priority to programs that best satisfy societal preferences. Societal preferences could be incorporated through the use of explicit equity weights, although more research is required before such weights can be used in priority setting. © The Author(s) 2014.

Education and patient preferences for treating type 2 diabetes: a stratified discrete-choice experiment

PubMed Central

Janssen, Ellen M; Longo, Daniel R; Bardsley, Joan K; Bridges, John FP

2017-01-01

Purpose Diabetes is a chronic condition that is more prevalent among people with lower educational attainment. This study assessed the treatment preferences of patients with type 2 diabetes by educational attainment. Methods Patients with type 2 diabetes were recruited from a national online panel in the US. Treatment preferences were assessed using a discrete-choice experiment. Participants completed 16 choice tasks in which they compared pairs of treatment profiles composed of six attributes: A1c decrease, stable blood glucose, low blood glucose, nausea, treatment burden, and out-of-pocket cost. Choice models and willingness-to-pay (WTP) estimates were estimated using a conditional logit model and were stratified by educational status. Results A total of 231 participants with a high school diploma or less education, 156 participants with some college education, and 165 participants with a college degree or more completed the survey. Participants with a college degree or more education were willing to pay more for A1c decreases ($58.84, standard error [SE]: 10.6) than participants who had completed some college ($28.47, SE: 5.53) or high school or less ($17.56, SE: 3.55) (p≤0.01). People with a college education were willing to pay more than people with high school or less to avoid nausea, low blood glucose events during the day/night, or two pills per day. Conclusion WTP for aspects of diabetes medication differed for people with a college education or more and a high school education or less. Advanced statistical methods might overcome limitations of stratification and advance understanding of preference heterogeneity for use in patient-centered benefit–risk assessments and personalized care approaches. PMID:29070940

Education and patient preferences for treating type 2 diabetes: a stratified discrete-choice experiment.

PubMed

Janssen, Ellen M; Longo, Daniel R; Bardsley, Joan K; Bridges, John Fp

2017-01-01

Diabetes is a chronic condition that is more prevalent among people with lower educational attainment. This study assessed the treatment preferences of patients with type 2 diabetes by educational attainment. Patients with type 2 diabetes were recruited from a national online panel in the US. Treatment preferences were assessed using a discrete-choice experiment. Participants completed 16 choice tasks in which they compared pairs of treatment profiles composed of six attributes: A1c decrease, stable blood glucose, low blood glucose, nausea, treatment burden, and out-of-pocket cost. Choice models and willingness-to-pay (WTP) estimates were estimated using a conditional logit model and were stratified by educational status. A total of 231 participants with a high school diploma or less education, 156 participants with some college education, and 165 participants with a college degree or more completed the survey. Participants with a college degree or more education were willing to pay more for A1c decreases ($58.84, standard error [SE]: 10.6) than participants who had completed some college ($28.47, SE: 5.53) or high school or less ($17.56, SE: 3.55) ( p ≤0.01). People with a college education were willing to pay more than people with high school or less to avoid nausea, low blood glucose events during the day/night, or two pills per day. WTP for aspects of diabetes medication differed for people with a college education or more and a high school education or less. Advanced statistical methods might overcome limitations of stratification and advance understanding of preference heterogeneity for use in patient-centered benefit-risk assessments and personalized care approaches.

Modeling the Mental Health Practice Change Preferences of Educators: A Discrete-Choice Conjoint Experiment.

PubMed

Cunningham, Charles E; Barwick, Melanie; Short, Kathy; Chen, Yvonne; Rimas, Heather; Ratcliffe, Jenna; Mielko, Stephanie

2014-01-01

Schools are sometimes slow to adopt evidence-based strategies for improving the mental health outcomes of students. This study used a discrete-choice conjoint experiment to model factors influencing the decision of educators to adopt strategies for improving children's mental health outcomes. A sample of 1,010 educators made choices between hypothetical mental health practice change strategies composed by systematically varying the four levels of 16 practice change attributes. Latent class analysis yielded two segments with different practice change preferences. Both segments preferred small-group workshops, conducted by engaging experts, teaching skills applicable to all students. Participants expressed little interest in Internet options. The support of colleagues, administrators, and unions exerted a strong influence on the practice change choices of both segments. The Change Ready segment, 77.1 % of the sample, was more intent on adopting new strategies to improve the mental health of students. They preferred that schools, rather than the provincial ministry of education, make practice change decisions, coaching was provided to all participants, and participants received post-training follow-up sessions. The Demand Sensitive segment (22.9 %) was less intent on practice change. They preferred that individual teachers make practice change decisions, recommended discretionary coaching, and chose no post-training follow-up support. This study emphasizes the complex social, organizational, and policy context within which educators make practice change decisions. Efforts to disseminate strategies to improve the mental health outcomes of students need to be informed by the preferences of segments of educators who are sensitive to different dimensions of the practice change process. In the absence of a broad consensus of educators, administrators, and unions, potentially successful practice changes are unlikely to be adopted.

The choice and preference for public-private health care among urban residents in China: evidence from a discrete choice experiment.

PubMed

Tang, Chengxiang; Xu, Judy; Zhang, Meng

2016-10-18

Public health care dominated the services provision in China before 1980s. However, the number of private health care providers in China has been increasing since then. The growth of private hospitals escalated after a market-oriented reform was implemented in 2001. Through an experimental approach, this study aims to a better understanding of the dynamic change in preference of health care utilisation among the residents in urban China. Based on a discrete choice experiment (DCE) from a random sample of respondents in urban China, the study evaluated preference over health care attributes affecting individuals' choice for the utilisation of hospital health care. The marginal willingness-to-pay for five health care attributes was estimated, including public/private provision of health care, by analysing mixed logit and latent class models. The results indicated a significantly negative marginal willingness-to-pay for private health care, which was interpreted as representing people's previous interactions with the health care system. The latent class model further suggested preference heterogeneity across our sample. We found that Hukou type, a typical indicator of socioeconomic background, was significantly related to respondents' preference for health care utilisation. Permanent urban residents (urban Hukou) valued private health care less; in contrast rural migrants (rural Hukou) were more likely to be indifferent between public/private provision. Urban residents in China showed a high disposition to obtain health care from the public providers of health care. Our results have implications in the context of the Chinese government attempts to expand the private health care sector in the short term. Policy makers need to consider residents' preference for health care in health policy development as the preference can only change in the long term.

Eliciting preferences for waterpipe tobacco smoking using a discrete choice experiment: implications for product regulation

PubMed Central

Salloum, Ramzi G; Maziak, Wasim; Hammond, David; Nakkash, Rima; Islam, Farahnaz; Cheng, Xi; Thrasher, James F

2015-01-01

Objectives Waterpipe smoking is highly prevalent among university students, and has been increasing in popularity despite mounting evidence showing it is harmful to health. The aim of this study was to measure preferences for waterpipe smoking and determine which product characteristics are most important to smokers. Setting A large university in the Southeastern USA. Participants Adult waterpipe smokers attending the university (N=367). Design Participants completed an Internet-based discrete choice experiment to reveal their preferences for, and trade-offs between, the attributes of hypothetical waterpipe smoking sessions. Participants were presented with waterpipe lounge menus, each with three fruit-flavoured options and one tobacco flavoured option, in addition to an opt out option. Nicotine content and price were provided for each choice. Participants were randomised to either receive menus with a text-only health-warning message or no message. Outcome measures Multinomial and nested logit models were used to estimate the impact on consumer choice of attributes and between-subject assignment of health warnings respectively. Results On average, participants preferred fruit-flavoured varieties to tobacco flavour. They were averse to options labelled with higher nicotine content. Females and non-smokers of cigarettes were more likely than their counterparts to prefer flavoured and nicotine-free varieties. Participants exposed to a health warning were more likely to opt out. Conclusions Fruit-flavoured tobacco and lower nicotine content labels, two strategies widely used by the industry, increase the demand for waterpipe smoking among young adults. Waterpipe-specific regulation should limit the availability of flavoured waterpipe tobacco and require accurate labelling of constituents. Waterpipe-specific tobacco control regulation, along with research to inform policy, is required to curb this emerging public health threat. PMID:26353876

Prioritising health service innovation investments using public preferences: a discrete choice experiment.

PubMed

Erdem, Seda; Thompson, Carl

2014-08-28

Prioritising scarce resources for investment in innovation by publically funded health systems is unavoidable. Many healthcare systems wish to foster transparency and accountability in the decisions they make by incorporating the public in decision-making processes. This paper presents a unique conceptual approach exploring the public's preferences for health service innovations by viewing healthcare innovations as 'bundles' of characteristics. This decompositional approach allows policy-makers to compare numerous competing health service innovations without repeatedly administering surveys for specific innovation choices. A Discrete Choice Experiment (DCE) was used to elicit preferences. Individuals chose from presented innovation options that they believe the UK National Health Service (NHS) should invest the most in. Innovations differed according to: (i) target population; (ii) target age; (iii) implementation time; (iv) uncertainty associated with their likely effects; (v) potential health benefits; and, (vi) cost to a taxpayer. This approach fosters multidimensional decision-making, rather than imposing a single decision criterion (e.g., cost, target age) in prioritisation. Choice data was then analysed using scale-adjusted Latent Class models to investigate variability in preferences and scale and valuations amongst respondents. Three latent classes with considerable heterogeneity in the preferences were present. Each latent class is composed of two consumer subgroups varying in the level of certainty in their choices. All groups preferred scientifically proven innovations, those with potential health benefits that cost less. There were, however, some important differences in their preferences for innovation investment choices: Class-1 (54%) prefers innovations benefitting adults and young people and does not prefer innovations targeting people with 'drug addiction' and 'obesity'. Class- 2 (34%) prefers innovations targeting 'cancer' patients only and has negative preferences for innovations targeting elderly, and Class-3 (12%) prefers spending on elderly and cancer patients the most. DCE can help policy-makers incorporate public preferences for health service innovation investment choices into decision making. The findings provide useful information on the public's valuation and acceptability of potential health service innovations. Such information can be used to guide innovation prioritisation decisions by comparing competing innovation options. The approach in this paper makes, these often implicit and opaque decisions, more transparent and explicit.

Rescaling quality of life values from discrete choice experiments for use as QALYs: a cautionary tale

PubMed Central

Flynn, Terry N; Louviere, Jordan J; Marley, Anthony AJ; Coast, Joanna; Peters, Tim J

2008-01-01

Background Researchers are increasingly investigating the potential for ordinal tasks such as ranking and discrete choice experiments to estimate QALY health state values. However, the assumptions of random utility theory, which underpin the statistical models used to provide these estimates, have received insufficient attention. In particular, the assumptions made about the decisions between living states and the death state are not satisfied, at least for some people. Estimated values are likely to be incorrectly anchored with respect to death (zero) in such circumstances. Methods Data from the Investigating Choice Experiments for the preferences of older people CAPability instrument (ICECAP) valuation exercise were analysed. The values (previously anchored to the worst possible state) were rescaled using an ordinal model proposed previously to estimate QALY-like values. Bootstrapping was conducted to vary artificially the proportion of people who conformed to the conventional random utility model underpinning the analyses. Results Only 26% of respondents conformed unequivocally to the assumptions of conventional random utility theory. At least 14% of respondents unequivocally violated the assumptions. Varying the relative proportions of conforming respondents in sensitivity analyses led to large changes in the estimated QALY values, particularly for lower-valued states. As a result these values could be either positive (considered to be better than death) or negative (considered to be worse than death). Conclusion Use of a statistical model such as conditional (multinomial) regression to anchor quality of life values from ordinal data to death is inappropriate in the presence of respondents who do not conform to the assumptions of conventional random utility theory. This is clearest when estimating values for that group of respondents observed in valuation samples who refuse to consider any living state to be worse than death: in such circumstances the model cannot be estimated. Only a valuation task requiring respondents to make choices in which both length and quality of life vary can produce estimates that properly reflect the preferences of all respondents. PMID:18945358

Young People’s Preferences for Family Planning Service Providers in Rural Malawi: A Discrete Choice Experiment

PubMed Central

Michaels-Igbokwe, Christine; Terris-Prestholt, Fern; Lagarde, Mylene; Chipeta, Effie; Cairns, John

2015-01-01

Objective To quantify the impact of service provider characteristics on young people’s choice of family planning (FP) service provider in rural Malawi in order to identify strategies for increasing access and uptake of FP among youth. Methods and Findings A discrete choice experiment was developed to assess the relative impact of service characteristics on preferences for FP service providers among young people (aged 15–24). Four alternative providers were included (government facility, private facility, outreach and community based distribution of FP) and described by six attributes (the distance between participants’ home and the service delivery point, frequency of service delivery, waiting time at the facility, service providers’ attitude, availability of FP commodities and price). A random parameters logit model was used to estimate preferences for service providers and the likely uptake of services following the expansion of outreach and community based distribution (CBDA) services. In the choice experiment young people were twice as likely to choose a friendly provider (government service odds ratio [OR] = 2.45, p<0.01; private service OR = 1.99, p<0.01; CBDA OR = 1.88, p<0.01) and more than two to three times more likely to choose a provider with an adequate supply of FP commodities (government service OR = 2.48, p<0.01; private service OR = 2.33, p<0.01; CBDA = 3.85, p<0.01). Uptake of community based services was greater than facility based services across a variety of simulated service scenarios indicating that such services may be an effective means of expanding access for youth in rural areas and an important tool for increasing service uptake among youth. Conclusions Ensuring that services are acceptable to young people may require additional training for service providers in order to ensure that all providers are friendly and non-judgemental when dealing with younger clients and to ensure that supplies are consistently available. PMID:26630492

Factors that influence clinicians' decisions to offer intravenous alteplase in acute ischemic stroke patients with uncertain treatment indication: Results of a discrete choice experiment.

PubMed

De Brún, Aoife; Flynn, Darren; Ternent, Laura; Price, Christopher I; Rodgers, Helen; Ford, Gary A; Rudd, Matthew; Lancsar, Emily; Simpson, Stephen; Teah, John; Thomson, Richard G

2018-01-01

Background Treatment with intravenous alteplase for eligible patients with acute ischemic stroke is underused, with variation in treatment rates across the UK. This study sought to elucidate factors influencing variation in clinicians' decision-making about this thrombolytic treatment. Methods A discrete choice experiment using hypothetical patient vignettes framed around areas of clinical uncertainty was conducted with UK-based clinicians. Mixed logit regression analyses were conducted on the data. Results A total of 138 clinicians completed the discrete choice experiment. Seven patient factors were individually predictive of increased likelihood of immediately offering IV alteplase (compared to reference levels in brackets): stroke onset time 2 h 30 min [50 min]; pre-stroke dependency mRS 3 [mRS 4]; systolic blood pressure 185 mm/Hg [140 mm/Hg]; stroke severity scores of NIHSS 5 without aphasia, NIHSS 14 and NIHSS 23 [NIHSS 2 without aphasia]; age 85 [68]; Afro-Caribbean [white]. Factors predictive of withholding treatment with IV alteplase were: age 95 [68]; stroke onset time of 4 h 15 min [50 min]; severe dementia [no memory problems]; SBP 200 mm/Hg [140 mm/Hg]. Three clinician-related factors were predictive of an increased likelihood of offering IV alteplase (perceived robustness of the evidence for IV alteplase; thrombolyzing more patients in the past 12 months; and high discomfort with uncertainty) and one with a decreased likelihood (high clinician comfort with treating patients outside the licensing criteria). Conclusions Both patient- and clinician-related factors have a major influence on the use of alteplase to treat patients with acute ischemic stroke. Clinicians' views of the evidence, comfort with uncertainty and treating patients outside the license criteria are important factors to address in programs that seek to reduce variation in care quality regarding treatment with IV alteplase. Further research is needed to further understand the differences in clinical decision-making about treating patients with acute ischemic stroke with IV alteplase.

Developing attributes and attribute-levels for a discrete choice experiment on micro health insurance in rural Malawi.

PubMed

Abiiro, Gilbert Abotisem; Leppert, Gerald; Mbera, Grace Bongololo; Robyn, Paul J; De Allegri, Manuela

2014-05-22

Discrete choice experiments (DCEs) are attribute-driven experimental techniques used to elicit stakeholders' preferences to support the design and implementation of policy interventions. The validity of a DCE, therefore, depends on the appropriate specification of the attributes and their levels. There have been recent calls for greater rigor in implementing and reporting on the processes of developing attributes and attribute-levels for discrete choice experiments (DCEs). This paper responds to such calls by carefully reporting a systematic process of developing micro health insurance attributes and attribute-levels for the design of a DCE in rural Malawi. Conceptual attributes and attribute-levels were initially derived from a literature review which informed the design of qualitative data collection tools to identify context specific attributes and attribute-levels. Qualitative data was collected in August-September 2012 from 12 focus group discussions with community residents and 8 in-depth interviews with health workers. All participants were selected according to stratified purposive sampling. The material was tape-recorded, fully transcribed, and coded by three researchers to identify context-specific attributes and attribute-levels. Expert opinion was used to scale down the attributes and levels. A pilot study confirmed the appropriateness of the selected attributes and levels for a DCE. First, a consensus, emerging from an individual level analysis of the qualitative transcripts, identified 10 candidate attributes. Levels were assigned to all attributes based on data from transcripts and knowledge of the Malawian context, derived from literature. Second, through further discussions with experts, four attributes were discarded based on multiple criteria. The 6 remaining attributes were: premium level, unit of enrollment, management structure, health service benefit package, transportation coverage and copayment levels. A final step of revision and piloting confirmed that the retained attributes satisfied the credibility criteria of DCE attributes. This detailed description makes our attribute development process transparent, and provides the reader with a basis to assess the rigor of this stage of constructing the DCE. This paper contributes empirical evidence to the limited methodological literature on attributes and levels development for DCE, thereby providing further empirical guidance on the matter, specifically within rural communities of low- and middle-income countries.

Preferences for support services among adolescents and young adults with cancer or a blood disorder: a discrete choice experiment.

PubMed

Goodall, Stephen; King, Madeleine; Ewing, Jane; Smith, Narelle; Kenny, Patricia

2012-10-01

Life-threatening illnesses in young people are traumatic for patients and their families. Support services can help patients and families deal with various non-medical impacts of diagnosis, disease and treatment. The aim of this study was to determine which types of support are most valued by adolescents and young adults (AYA) with cancer or blood disorders and their families. A discrete choice experiment (DCE). Separate experiments were conducted with AYA and their carers. Completed surveys were returned by 83 patients and 78 carers. AYA preferred emotional support for themselves (either by counsellors and/or peers), emotional support for their family, financial support and assistance returning to school/work over services relating to cultural and spiritual needs. Covariate analysis indicated female AYA were more likely than males to prefer emotional support, while males were more likely to prefer assistance returning to work/school. Carers preferred emotional support for their AYA and assistance returning to school/work. Like AYA, they were indifferent about services relating to cultural and spiritual needs. Providing the types of support services that people prefer should maximise effectiveness. This study suggests that AYA patients require support services that included financial aid, assistance returning to work/study, emotional support for themselves and for their family. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

The impact of flavour, device type and warning messages on youth preferences for electronic nicotine delivery systems: evidence from an online discrete choice experiment.

PubMed

Shang, Ce; Huang, Jidong; Chaloupka, Frank J; Emery, Sherry L

2017-11-02

To examine the impact of flavour, device type and health warning messages on youth preference for electronic nicotine delivery systems (ENDS), and to provide evidence and data to inform the Food and Drug Administration's potential regulatory actions on ENDS. An online discrete choice experiment was conducted in September 2015. Each participant was given nine choice sets and asked to choose one out of two alternative ENDS products, with varying characteristics in three attributes (flavour, device type and warning message). The impact of the attributes on the probability of choosing ENDS was analysed using conditional and nested logit regressions, controlling for individual sociodemographic characteristics and current smoking status. A general population sample of 515 participants (50 ever-users and 465 never-users of ENDS) aged 14-17 years were recruited to complete the experiment using an online panel. Fruit/sweets/beverage flavours significantly increase the probability of choosing ENDS among youth (p<0.01 for never-users and <0.1 for ever-users) and flavour has the most pronounced impact among three attributes. Among never-users, menthol flavour also increases (p<0.05) the probability of choosing ENDS compared with tobacco flavour. Vaping devices that are modifiable, compared with cigarette-like e-cigarettes, increase (p<0.05) the probability of choosing ENDS among adolescent never-users. Warning messages reduce (p<0.01) the probability of choosing ENDS among never-users. Restricting fruit/sweets/beverage flavours in ENDS, regulating modifiable vaping devices and adopting strong health warning messages may reduce the uptake of ENDS among youth. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Environmental Factors in the Choice of EGMs: A Discrete Choice Experiment.

PubMed

Rockloff, Matthew J; Moskovsky, Neda; Thorne, Hannah; Browne, Matthew; Bryden, Gabrielle M

2017-09-01

EGMs are a form of entertainment, and the gambling environment is an important contributor to the overall experience. Logically, to select a play-environment, EGM gamblers must choose the platform through which to access the EGM (e.g., internet, mobile application or land-based venue), a particular provider (e.g., specific website, app vendor or branded casino), and the game itself (e.g., based on graphical theme or bonus features; Thorne et al. in J Gambl Stud, 2016. doi: 10.1007/s10899-016-9601-2 ). A discrete choice experiment was conducted to identify the features of the platform, provider and game that are most strongly preferred by EGM gamblers. Participants were 245 EGM gamblers from clubs in Victoria, Australia and 7516 EGM gamblers from an Australian online panel. Results indicate that the ideal environment for the average gambler consists of: gambling at a club that is close to home; with a group of friends; in a relatively quiet place that has air conditioning, cheap food and a large space to play in; on a classic game with quality animations and small bet sizes; where you feel safe and secure; and where there is a wide variety of other games to play when you are done. Segmenting these results by problem-gambler status highlights important differences in preferences between problem and non-problem gamblers. Problem gamblers are less likely to give weight to the company they share and have a preference for larger venues. Using a powerful paradigm from marketing research, the present study was able to determine the relative value of different features of the EGM gambling environment, and also contributes important insight towards what constitutes a safer environment for recreational play.

Token reinforcement, choice, and self-control in pigeons.

PubMed Central

Jackson, K; Hackenberg, T D

1996-01-01

Pigeons were exposed to self-control procedures that involved illumination of light-emitting diodes (LEDs) as a form of token reinforcement. In a discrete-trials arrangement, subjects chose between one and three LEDs; each LED was exchangeable for 2-s access to food during distinct posttrial exchange periods. In Experiment 1, subjects generally preferred the immediate presentation of a single LED over the delayed presentation of three LEDs, but differences in the delay to the exchange period between the two options prevented a clear assessment of the relative influence of LED delay and exchange-period delay as determinants of choice. In Experiment 2, in which delays to the exchange period from either alternative were equal in most conditions, all subjects preferred the delayed three LEDs more often than in Experiment-1. In Experiment 3, subjects preferred the option that resulted in a greater amount of food more often if the choices also produced LEDs than if they did not. In Experiment 4, preference for the delayed three LEDs was obtained when delays to the exchange period were equal, but reversed in favor of an immediate single LED when the latter choice also resulted in quicker access to exchange periods. The overall pattern of results suggests that (a) delay to the exchange period is a more critical determinant of choice than is delay to token presentation; (b) tokens may function as conditioned reinforcers, although their discriminative properties may be responsible for the self-control that occurs under token reinforcer arrangements; and (c) previously reported differences in the self-control choices of humans and pigeons may have resulted at least in part from the procedural conventions of using token reinforcers with human subjects and food reinforcers with pigeon subjects. PMID:8755699

Conducting a Discrete-Choice Experiment Study Following Recommendations for Good Research Practices: An Application for Eliciting Patient Preferences for Diabetes Treatments.

PubMed

Janssen, Ellen M; Hauber, A Brett; Bridges, John F P

2018-01-01

To consolidate and illustrate good research practices in health care to the application and reporting of a study measuring patient preferences for type 2 diabetes mellitus medications, given recent methodological advances in stated-preference methods. The International Society for Pharmacoeconomics and Outcomes Research good research practices and other recommendations were used to conduct a discrete-choice experiment. Members of a US online panel with type 2 diabetes mellitus completed a Web-enabled, self-administered survey that elicited choices between treatment pairs with six attributes at three possible levels each. A D-efficient experimental design blocked 48 choice tasks into three 16-task surveys. Preference estimates were obtained using mixed logit estimation and were used to calculate choice probabilities. A total of 552 participants (51% males) completed the survey. Avoiding 90 minutes of nausea was valued the highest (mean -10.00; 95% confidence interval [CI] -10.53 to -9.47). Participants wanted to avoid low blood glucose during the day and/or night (mean -3.87; 95% CI -4.32 to -3.42) or one pill and one injection per day (mean -7.04; 95% CI -7.63 to -6.45). Participants preferred stable blood glucose 6 d/wk (mean 4.63; 95% CI 4.15 to 5.12) and a 1% decrease in glycated hemoglobin (mean 5.74; 95% CI 5.22 to 6.25). If cost increased by $1, the probability that a treatment profile would be chosen decreased by 1%. These results are consistent with the idea that people have strong preferences for immediate consequences of medication. Despite efforts to produce recommendations, ambiguity surrounding good practices remains and various judgments need to be made when conducting stated-preference studies. To ensure transparency, these judgments should be described and justified. Copyright © 2018 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Individual decisions to vaccinate one's child or oneself: A discrete choice experiment rejecting free-riding motives.

PubMed

Verelst, Frederik; Willem, Lander; Kessels, Roselinde; Beutels, Philippe

2018-06-01

It is essential for public health to understand what drives people's hesitance towards vaccination. Theoretical models of vaccination decisions are ubiquitous, often incorporating herd immunity, perceptions of vaccine-related side-effects (VRSE) and of vaccine-preventable burden of disease, but with little to no empirical exploration. Herd immunity is a (usually) positive externality where vaccinated individuals influence others' risks by their reduced capability to transmit an infectious disease to them. It is often assumed that (rational) individuals incorporate this externality in their strategic vaccination decision, from which free-riding behavior arises. We performed a Bayesian D-efficient discrete choice experiment in February-March 2017 to study vaccination behavior in 1919 Belgian respondents. Choice sets with vaccine profiles were constructed using six attributes: vaccine effectiveness, VRSE, accessibility (in terms of convenience and reimbursement), vaccine-preventable burden of disease, local (respondents' network of contacts) vaccination coverage, and population (the population at large) vaccination coverage. VRSE and accessibility are the most influential attributes, followed by vaccine effectiveness and burden of disease. Both population and local coverage are less important than the other attributes, but show a significant direct linear relationship with vaccine utility. This supports the existence of peer influence (more incentivized as more and more vaccinate), rather than free-riding on herd immunity. These findings were independent of whether respondents made vaccine choices for themselves or for their child. Around 40% of the respondents indicated accepting vaccination with little or no questioning. These 'acceptors' were less sensitive to changes in the vaccine-preventable burden of disease for their child's vaccination choices (but not for themselves). Public health institutions are critical in stimulating vaccine uptake by making vaccines conveniently available at an affordable price and by communicating pro-actively on perceived VRSEs. The free-riding assumption as a driver of individual vaccine decisions, seems inappropriate, but this observation needs confirming in other populations. Copyright © 2018 Elsevier Ltd. All rights reserved.

Investigating consumers' and informal carers' views and preferences for consumer directed care: A discrete choice experiment.

PubMed

Kaambwa, Billingsley; Lancsar, Emily; McCaffrey, Nicola; Chen, Gang; Gill, Liz; Cameron, Ian D; Crotty, Maria; Ratcliffe, Julie

2015-09-01

Consumer directed care (CDC) is currently being embraced internationally as a means to promote autonomy and choice for consumers (people aged 65 and over) receiving community aged care services (CACSs). CDC involves giving CACS clients (consumers and informal carers of consumers) control over how CACSs are administered. However, CDC models have largely developed in the absence of evidence on clients' views and preferences. We explored CACS clients' preferences for a variety of CDC attributes and identified factors that may influence these preferences and potentially inform improved design of future CDC models. Study participants were clients of CACSs delivered by five Australian providers. Using a discrete choice experiment (DCE) approach undertaken in a group setting between June and December 2013, we investigated the relative importance to CACS consumers and informal (family) carers of gradations relating to six salient features of CDC (choice of service provider(s), budget management, saving unused/unspent funds, choice of support/care worker(s), support-worker flexibility and level of contact with service coordinator). The DCE data were analysed using conditional, mixed and generalised logit regression models, accounting for preference and scale heterogeneity. Mean ages for 117 study participants were 80 years (87 consumers) and 74 years (30 informal carers). All participants preferred a CDC approach that allowed them to: save unused funds from a CACS package for future use; have support workers that were flexible in terms of changing activities within their CACS care plan and; choose the support workers that provide their day-to-day CACSs. The CDC attributes found to be important to both consumers and informal carers receiving CACSs will inform the design of future CDC models of service delivery. The DCE approach used in this study has the potential for wide applicability and facilitates the assessment of preferences for elements of potential future aged care service delivery not yet available in policy. Copyright © 2015 Elsevier Ltd. All rights reserved.

German travelers' preferences for travel vaccines assessed by a discrete choice experiment.

PubMed

Poulos, Christine; Curran, Desmond; Anastassopoulou, Anastassia; De Moerlooze, Laurence

2018-02-08

Many travelers to regions with endemic infectious diseases do not follow health authorities' recommendations regarding vaccination against vaccine-preventable infectious diseases, before traveling. The determinants of individual travelers' decisions to vaccinate before traveling are largely unknown. This study aimed to provide this information using a discrete choice experiment (DCE) administered to four types of German travelers: (1) business travelers; (2) travelers visiting friends and relatives (VFR); (3) leisure travelers; and (4) backpackers. A DCE survey was developed, pretested and administered online. It included a series of choice questions in which respondents chose between two hypothetical vaccines, each characterized by four disease attributes with varying levels describing the of risk, health impact, curability and transmissibility of the disease they would prevent (described with four disease attributes with varying levels of risk, health impact, curability and transmissibility), and varying levels of four vaccine attributes (duration of protection, number of doses required, time required for vaccination, and vaccine cost). A random-parameters logit model was used to estimate the importance weights each traveler type placed on the various attribute levels. These weights were used to calculate mean monetary equivalents (MMEs) of changes in each attribute (holding all others constant) and of hypothetical disease-vaccine combinations. All traveler types' choices indicated that they attached the greatest importance to the risk and health impact of disease and to the vaccine cost whereas the other disease and vaccine attributes were less important for their decisions about travel vaccines. An option of not choosing any of the vaccine-pairs presented was rarely selected indicating that travelers' generally prefer to be vaccinated rather than not. The MMEs of changes in vaccine attributes indicated a very high variability between the individual travelers within each type. The travelers' responses indicated strong preferences for selecting vaccination rather than opting out of vaccination, and disease risk, health impact and vaccine cost were the most important features for vaccine choice. Copyright © 2018. Published by Elsevier Ltd.

Order of Presentation of Dimensions Does Not Systematically Bias Utility Weights from a Discrete Choice Experiment.

PubMed

Norman, Richard; Kemmler, Georg; Viney, Rosalie; Pickard, A Simon; Gamper, Eva; Holzner, Bernhard; Nerich, Virginie; King, Madeleine

2016-12-01

Discrete choice experiments (DCEs) are increasingly used to value aspects of health. An issue with their adoption is that results may be sensitive to the order in which dimensions of health are presented in the valuation task. Findings in the literature regarding order effects are discordant at present. To quantify the magnitude of order effect of quality-of-life (QOL) dimensions within the context of a DCE designed to produce country-specific value sets for the EORTC Quality of Life Utility Measure-Core 10 dimensions (QLU-C10D), a new utility instrument derived from the widely used cancer-specific QOL questionnaire, the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30. The DCE comprised 960 choice sets, divided into 60 versions of 16 choice sets, with each respondent assigned to a version. Within each version, the order of QLU-C10D QOL dimensions was randomized, followed by life duration in the last position. The DCE was completed online by 2053 individuals in France and Germany. We analyzed the data with a series of conditional logit models, adjusted for repeated choices within respondent. We used F tests to assess order effects, correcting for multiple hypothesis testing. Each F test failed to reject the null hypothesis of no position effect: 1) all QOL order positions considered jointly; 2) last QOL position only; 3) first QOL position only. Furthermore, the order coefficients were small relative to those of the QLU-C10D QOL dimension levels. The order of presentation of QOL dimensions within a DCE designed to provide utility weights for the QLU-C10D had little effect on level coefficients of those QOL dimensions. Copyright © 2016 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Neural correlates of value, risk, and risk aversion contributing to decision making under risk.

PubMed

Christopoulos, George I; Tobler, Philippe N; Bossaerts, Peter; Dolan, Raymond J; Schultz, Wolfram

2009-10-07

Decision making under risk is central to human behavior. Economic decision theory suggests that value, risk, and risk aversion influence choice behavior. Although previous studies identified neural correlates of decision parameters, the contribution of these correlates to actual choices is unknown. In two different experiments, participants chose between risky and safe options. We identified discrete blood oxygen level-dependent (BOLD) correlates of value and risk in the ventral striatum and anterior cingulate, respectively. Notably, increasing inferior frontal gyrus activity to low risk and safe options correlated with higher risk aversion. Importantly, the combination of these BOLD responses effectively decoded the behavioral choice. Striatal value and cingulate risk responses increased the probability of a risky choice, whereas inferior frontal gyrus responses showed the inverse relationship. These findings suggest that the BOLD correlates of decision factors are appropriate for an ideal observer to detect behavioral choices. More generally, these biological data contribute to the validity of the theoretical decision parameters for actual decisions under risk.

Parameterising User Uptake in Economic Evaluations: The role of discrete choice experiments.

PubMed

Terris-Prestholt, Fern; Quaife, Matthew; Vickerman, Peter

2016-02-01

Model-based economic evaluations of new interventions have shown that user behaviour (uptake) is a critical driver of overall impact achieved. However, early economic evaluations, prior to introduction, often rely on assumed levels of uptake based on expert opinion or uptake of similar interventions. In addition to the likely uncertainty surrounding these uptake assumptions, they also do not allow for uptake to be a function of product, intervention, or user characteristics. This letter proposes using uptake projections from discrete choice experiments (DCE) to better parameterize uptake and substitution in cost-effectiveness models. A simple impact model is developed and illustrated using an example from the HIV prevention field in South Africa. Comparison between the conventional approach and the DCE-based approach shows that, in our example, DCE-based impact predictions varied by up to 50% from conventional estimates and provided far more nuanced projections. In the absence of observed uptake data and to model the effect of variations in intervention characteristics, DCE-based uptake predictions are likely to greatly improve models parameterizing uptake solely based on expert opinion. This is particularly important for global and national level decision making around introducing new and probably more expensive interventions, particularly where resources are most constrained. © 2016 The Authors. Health Economics published by John Wiley & Sons Ltd.

Patients' and urologists' preferences for prostate cancer treatment: a discrete choice experiment

PubMed Central

de Bekker-Grob, E W; Bliemer, M C J; Donkers, B; Essink-Bot, M-L; Korfage, I J; Roobol, M J; Bangma, C H; Steyerberg, E W

2013-01-01

Background: Patients' preferences are important for shared decision making. Therefore, we investigated patients' and urologists' preferences for treatment alternatives for early prostate cancer (PC). Methods: A discrete choice experiment was conducted among 150 patients who were waiting for their biopsy results, and 150 urologists. Regression analysis was used to determine patients' and urologists' stated preferences using scenarios based on PC treatment modality (radiotherapy, surgery, and active surveillance (AS)), and risks of urinary incontinence and erectile dysfunction. Results: The response rate was 110 out of 150 (73%) for patients and 50 out of 150 (33%) for urologists. Risk of urinary incontinence was an important determinant of both patients' and urologists' stated preferences for PC treatment (P<0.05). Treatment modality also influenced patients' stated preferences (P<0.05), whereas the risk of erectile dysfunction due to radiotherapy was mainly important to urologists (P<0.05). Both patients and urologists preferred AS to radical treatment, with the exception of patients with anxious/depressed feelings who preferred radical treatment to AS. Conclusion: Although patients and urologists generally may prefer similar treatments for PC, they showed different trade-offs between various specific treatment aspects. This implies that urologists need to be aware of potential differences compared with the patient's perspective on treatment decisions in shared decision making on PC treatment. PMID:23860533

Preferences for physician services in Ukraine: a discrete choice experiment.

PubMed

Danyliv, Andriy; Pavlova, Milena; Gryga, Irena; Groot, Wim

2015-01-01

Evidence on preferences of Ukrainian consumers for healthcare improvements can help to design reforms that correspond to societal priorities. This study aims to elicit and to place monetary values on public preferences for out-patient physician services in Ukraine. The method of discrete choice experiment is used on a sample of 303 respondents, representative of the adult Ukrainian population. The random effect logit model with interactions provides the best fit for the data and is used to calculate the marginal willingness to pay (MWTP) for quality and access improvements. At a sample level, there is no clear preference to pay formally rather than informally or vice versa. We also do not find that visiting a general practitioner is preferred over direct access to a medical specialist. However, there are differences between population groups. Quality-related attributes of physician services appear important to respondents, especially the attitude of medical staff. Thus, interpersonal aspects of out-patient care should be given priority in decisions about investments in quality improvements. Other aspects, that is social quality and access, are important as well but their improvement brings fewer social gains. Measures should be taken to eradicate the informal payment channels and to strengthen the gate-keeping role of primary care. Copyright © 2014 John Wiley & Sons, Ltd.

Using qualitative methods for attribute development for discrete choice experiments: issues and recommendations.

PubMed

Coast, Joanna; Al-Janabi, Hareth; Sutton, Eileen J; Horrocks, Susan A; Vosper, A Jane; Swancutt, Dawn R; Flynn, Terry N

2012-06-01

Attribute generation for discrete choice experiments (DCEs) is often poorly reported, and it is unclear whether this element of research is conducted rigorously. This paper explores issues associated with developing attributes for DCEs and contrasts different qualitative approaches. The paper draws on eight studies, four developed attributes for measures, and four developed attributes for more ad hoc policy questions. Issues that have become apparent through these studies include the following: the theoretical framework for random utility theory and the need for attributes that are neither too close to the latent construct nor too intrinsic to people's personality; the need to think about attribute development as a two-stage process involving conceptual development followed by refinement of language to convey the intended meaning; and the difficulty in resolving tensions inherent in the reductiveness of condensing complex and nuanced qualitative findings into precise terms. The comparison of alternative qualitative approaches suggests that the nature of data collection will depend both on the characteristics of the question (its sensitivity, for example) and the availability of existing qualitative information. An iterative, constant comparative approach to analysis is recommended. Finally, the paper provides a series of recommendations for improving the reporting of this element of DCE studies. Copyright © 2011 John Wiley & Sons, Ltd.

How to make rural jobs more attractive to health workers. Findings from a discrete choice experiment in Tanzania.

PubMed

Kolstad, Julie Riise

2011-02-01

The geographical imbalance of the health workforce in Tanzania represents a serious problem when it comes to delivering crucial health services to a large share of the population. This study provides new quantitative information about how to make jobs in rural areas more attractive to newly educated clinical officers (COs). A unique data set stemming from a discrete choice experiment with CO finalists in Tanzania is applied. The results show that offering continuing education after a certain period of service is one of the most powerful recruitment instruments the authorities have available. Increased salaries and hardship allowances will also substantially increase recruitment in rural areas. Offers of decent housing and good infrastructure, including the provision of equipment, will increase recruitment to rural remote areas but not as much as higher wages and offers of education. Women are less responsive to pecuniary incentives and are more concerned with factors that directly allow them to do a good job, while those with parents living in a remote rural area are generally less responsive to the proposed policies. When the willingness to help other people is a strong motivating force, policies that improve the conditions for helping people appear particularly effective.

The discrimination of discrete and continuous amounts in African grey parrots (Psittacus erithacus).

PubMed

Aïn, Syrina Al; Giret, Nicolas; Grand, Marion; Kreutzer, Michel; Bovet, Dalila

2009-01-01

A wealth of research in infants and animals demonstrates discrimination of quantities, in some cases nonverbal numerical perception, and even elementary calculation capacities. We investigated the ability of three African grey parrots (Psittacus erithacus) to select the largest amount of food between two sets, either discrete food items (experiment 1) or as volume of a food substance (experiment 2). The two amounts were presented simultaneously and were visible at the time of choice. Parrots were tested several times for all possible combinations between 1 and 5 seeds or 0.2 and 1 ml of food substance. In both conditions, subjects performed above chance for almost all combinations. Accuracy was negatively correlated with the ratio, that is performance improved with greater differences between amounts. Therefore, these results with both individual items and volume discrimination suggest that parrots use an analogue of magnitude, rather than object-file mechanisms to quantify items and substances.

What Do Patients Want from Otolaryngologists? A Discrete Choice Experiment.

PubMed

Naunheim, Matthew R; Rathi, Vinay K; Naunheim, Margaret L; Alkire, Blake C; Lam, Allen C; Song, Phillip C; Shrime, Mark G

2017-10-01

Objectives Patient preferences are crucial for the delivery of patient-centered care. Discrete choice experiments (DCEs) are an emerging quantitative methodology used for understanding these preferences. In this study, we employed DCE techniques to understand the preferences of patients presenting for an ear, nose, and throat clinic visit. Study Design DCE. Setting Decision science laboratory. Methods A DCE survey of 5 attributes-wait time, physician experience, physician personality, utilization of visit time, and cost/copayment-was constructed with structured qualitative interviews with patients. The DCE was administered to participants from the general population, who chose among hypothetical scenarios that varied across these attributes. A conditional logit model was used to determine relative attribute importance, with a separate logit model for determining subject effects. Results A total of 161 participants were included. Cost/copayment had the greatest impact on decision making (importance, 32.2%), followed by wait time and physician experience (26.5% and 24.7%, respectively). Physician personality mattered least (4.7%), although all attributes were significantly correlated to decision making. Participants preferred doctors who spent more time performing physical examination than listening or explaining. Participants were willing to pay $52 extra to avoid a 4-week delay in appointment time; $87 extra for a physician with 10 years of experience (vs 0 years); and $9 extra for a caring, friendly, and compassionate doctor (vs formal, efficient, and business-like). Conclusion DCEs allow for powerful economic analyses that may help physicians understand patient preferences. Our model showed that cost is an important factor to patients and that patients are willing to pay extra for timely appointments, experience, and thorough physical examination.

Think twice before you book? Modelling the choice of public vs private dentist in a choice experiment.

PubMed

Kiiskinen, Urpo; Suominen-Taipale, Anna Liisa; Cairns, John

2010-06-01

This study concerns the choice of primary dental service provider by consumers. If the health service delivery system allows individuals to choose between public-care providers or if complementary private services are available, it is typically assumed that utilisation is a three-stage decision process. The patient first makes a decision to seek care, and then chooses the service provider. The final stage, involving decisions over the amount and form of treatment, is not considered here. The paper reports a discrete choice experiment (DCE) designed to evaluate attributes affecting individuals' choice of dental-care provider. The feasibility of the DCE approach in modelling consumers' choice in the context of non-acute need for dental care is assessed. The aim is to test whether a separate two-stage logit, a multinomial logit, or a nested logit best fits the choice process of consumers. A nested logit model of indirect utility functions is estimated and inclusive value (IV) constraints are tested for modelling implications. The results show that non-trading behaviour has an impact on the choice of appropriate modelling technique, but is to some extent dependent on the choice of scenarios offered. It is concluded that for traders multinomial logit is appropriate, whereas for non-traders and on average the nested logit is the method supported by the analyses. The consistent finding in all subgroup analyses is that the traditional two-stage decision process is found to be implausible in the context of consumer's choice of dental-care provider.

A multiple indicator solution approach to endogeneity in discrete-choice models for environmental valuation.

PubMed

Mariel, Petr; Hoyos, David; Artabe, Alaitz; Guevara, C Angelo

2018-08-15

Endogeneity is an often neglected issue in empirical applications of discrete choice modelling despite its severe consequences in terms of inconsistent parameter estimation and biased welfare measures. This article analyses the performance of the multiple indicator solution method to deal with endogeneity arising from omitted explanatory variables in discrete choice models for environmental valuation. We also propose and illustrate a factor analysis procedure for the selection of the indicators in practice. Additionally, the performance of this method is compared with the recently proposed hybrid choice modelling framework. In an empirical application we find that the multiple indicator solution method and the hybrid model approach provide similar results in terms of welfare estimates, although the multiple indicator solution method is more parsimonious and notably easier to implement. The empirical results open a path to explore the performance of this method when endogeneity is thought to have a different cause or under a different set of indicators. Copyright © 2018 Elsevier B.V. All rights reserved.

Modeling organizational justice improvements in a pediatric health service : a discrete-choice conjoint experiment.

PubMed

Cunningham, Charles E; Kostrzewa, Linda; Rimas, Heather; Chen, Yvonne; Deal, Ken; Blatz, Susan; Bowman, Alida; Buchanan, Don H; Calvert, Randy; Jennings, Barbara

2013-01-01

Patients value health service teams that function effectively. Organizational justice is linked to the performance, health, and emotional adjustment of the members of these teams. We used a discrete-choice conjoint experiment to study the organizational justice improvement preferences of pediatric health service providers. Using themes from a focus group with 22 staff, we composed 14 four-level organizational justice improvement attributes. A sample of 652 staff (76 % return) completed 30 choice tasks, each presenting three hospitals defined by experimentally varying the attribute levels. Latent class analysis yielded three segments. Procedural justice attributes were more important to the Decision Sensitive segment, 50.6 % of the sample. They preferred to contribute to and understand how all decisions were made and expected management to act promptly on more staff suggestions. Interactional justice attributes were more important to the Conduct Sensitive segment (38.5 %). A universal code of respectful conduct, consequences encouraging respectful interaction, and management's response when staff disagreed with them were more important to this segment. Distributive justice attributes were more important to the Benefit Sensitive segment, 10.9 % of the sample. Simulations predicted that, while Decision Sensitive (74.9 %) participants preferred procedural justice improvements, Conduct (74.6 %) and Benefit Sensitive (50.3 %) participants preferred interactional justice improvements. Overall, 97.4 % of participants would prefer an approach combining procedural and interactional justice improvements. Efforts to create the health service environments that patients value need to be comprehensive enough to address the preferences of segments of staff who are sensitive to different dimensions of organizational justice.

A Discrete Choice Experiment to Elicit Patient Willingness to Pay for Attributes of Treatment-Induced Symptom Relief in Comorbid. Insomnia.

PubMed

Roy, Anuja N; Madhavan, S Suresh; Lloyd, Andrew

2015-04-01

Insomnia is a burdensome, commonly comorbid condition. How patients value various aspects of the safety and efficacy of available drugs has not been studied. The aim of the present study was to quantify patient-rated utility by studying willingness to pay (WTP) for attributes of symptom relief via a discrete choice experiment (DCE). Adult primary care patients (West Virginia University Hospital) with comorbid insomnia were enrolled. The attributes and levels examined were sleep onset latency (SOL; 10, 20,30 minutes), awakenings (1, 2, 3), wake time after sleep onset (WASO; 15,45, 60 minutes), total sleep time (TST; 6, 7, 8 hours), hangover (none, mild, moderate), FDA-approved duration of use (short term, not restricted to short term, no restrictions), and out-of-pocket cost per month ($20, $35, $50). Willingness to pay (WTP) data were analyzed using a random effects binary logistic regression model. A total of 82 patients completed the DCE (74 analyzed). SOL, WASO, TST, and cost were all found to predict treatment choice. Higher values of SOL, WASO, and cost resulted in decreased preference for a particular treatment, while higher TST predicted increased preference. Modeling revealed an estimated marginal WTP of $66.69 for an example product that improved SOL by 10 minutes, reduced WASO by 15 minutes, and improved TST by 1 hour. Patient WTP for symptomatic relief in insomnia can help clinicians fine-tune interventions based on patient preferences, provide evidence for drug formulary and reimbursement decisions, and potentially guide the development of novel drugs.

Preferences for Early Intervention Mental Health Services: A Discrete-Choice Conjoint Experiment.

PubMed

Becker, Mackenzie P E; Christensen, Bruce K; Cunningham, Charles E; Furimsky, Ivana; Rimas, Heather; Wilson, Fiona; Jeffs, Lisa; Bieling, Peter J; Madsen, Victoria; Chen, Yvonne Y S; Mielko, Stephanie; Zipursky, Robert B

2016-02-01

Early intervention services (EISs) for mental illness may improve outcomes, although treatment engagement is often a problem. Incorporating patients' preferences in the design of interventions improves engagement. A discrete-choice conjoint experiment was conducted in Canada to identify EIS attributes that encourage treatment initiation. Sixteen four-level attributes were formalized into a conjoint survey, completed by patients, family members, and mental health professionals (N=562). Participants were asked which EIS option people with mental illness would contact. Latent-class analysis identified respondent classes characterized by shared preferences. Randomized first-choice simulations predicted which hypothetical options, based on attributes, would result in maximum utilization. Participants in the conventional-service class (N=241, 43%) predicted that individuals would contact traditional services (for example, hospital location and staffed by psychologists or psychiatrists). Membership was associated with being a patient or family member and being male. Participants in the convenient-service class (N=321, 57%) predicted that people would contact services promoting easy access (for example, self-referral and access from home). Membership was associated with being a professional. Both classes predicted that people would contact services that included short wait times, direct contact with professionals, patient autonomy, and psychological treatment information. The convenient-service class predicted that people would use an e-health model, whereas the conventional-service class predicted that people would use a primary care or clinic-hospital model. Provision of a range of services may maximize EIS use. Professionals may be more apt to adopt EISs in line with their beliefs regarding patient preferences. Considering several perspectives is important for service design.

Characterizing outcome preferences in patients with psychotic disorders: a discrete choice conjoint experiment.

PubMed

Zipursky, Robert B; Cunningham, Charles E; Stewart, Bailey; Rimas, Heather; Cole, Emily; Vaz, Stephanie McDermid

2017-07-01

The majority of individuals with schizophrenia will achieve a remission of psychotic symptoms, but few will meet criteria for recovery. Little is known about what outcomes are important to patients. We carried out a discrete choice experiment to characterize the outcome preferences of patients with psychotic disorders. Participants (N=300) were recruited from two clinics specializing in psychotic disorders. Twelve outcomes were each defined at three levels and incorporated into a computerized survey with 15 choice tasks. Utility values and importance scores were calculated for each outcome level. Latent class analysis was carried out to determine whether participants were distributed into segments with different preferences. Multinomial logistic regression was used to identify predictors of segment membership. Latent class analysis revealed three segments of respondents. The first segment (48%), which we labeled "Achievement-focused," preferred to have a full-time job, to live independently, to be in a long-term relationship, and to have no psychotic symptoms. The second segment (29%), labeled "Stability-focused," preferred to not have a job, to live independently, and to have some ongoing psychotic symptoms. The third segment (23%), labeled "Health-focused," preferred to not have a job, to live in supervised housing, and to have no psychotic symptoms. Segment membership was predicted by education, socioeconomic status, psychotic symptom severity, and work status. This study has revealed that patients with psychotic disorders are distributed between segments with different outcome preferences. New approaches to improve outcomes for patients with psychotic disorders should be informed by a greater understanding of patient preferences and priorities. Copyright © 2016 Elsevier B.V. All rights reserved.

A discrete choice experiment to explore patients' willingness to risk disease relapse from treatment withdrawal in psoriatic arthritis.

PubMed

Rothery, Claire; Bojke, Laura; Richardson, Gerry; Bojke, Chris; Moverley, Anna; Coates, Laura; Thorp, Liz; Waxman, Robin; Helliwell, Philip

2016-12-01

The objective of this study is to assess patient preferences for treatment-related benefits and risk of disease relapse in the management of low disease states of psoriatic arthritis (PsA). Focus groups with patients and a literature review were undertaken to determine the characteristics of treatment and symptoms of PsA important to patients. Patient preferences were assessed using a discrete choice experiment which compared hypothetical treatment profiles of the risk and benefits of treatment withdrawal. The risk outcome included increased risk of disease relapse, while benefit outcomes included reduced sickness/nausea from medication and changes in health-related quality of life. Each patient completed 12 choice sets comparing treatment profiles. Preference weights were estimated using a logic regression model, and the maximum acceptable risk in disease relapse for a given improvement in benefit outcomes was elicited. Final sample included 136 patients. Respondents attached the greatest importance to eliminating severe side effects of sickness/nausea and the least importance to a change in risk of relapse. Respondents were willing to accept an increase in the risk of relapse of 32.6 % in order to eliminate the side effects of sickness/nausea. For improvements in health status, the maximum acceptable risk in relapse was comparable to a movement from some to no sickness/nausea. The study suggests that patients in low disease states of PsA are willing to accept greater risks of relapse for improvements in side effects of sickness/nausea and overall health status, with the most important benefit attribute being the elimination of severe sickness or nausea.

Preferences of overweight and obese patients for weight loss programmes: a discrete-choice experiment

PubMed Central

Mühlbacher, Axel; Bethge, Susanne

2013-01-01

Introduction Obesity is associated with increased risk of morbidity and mortality and also appears to have an adverse effect on health-related quality of life. Though advances in obesity therapy and rehabilitation can be observed, the long-lasting outcome is dissatisfying to most of the patients and, therefore, the whole health care system. Theory and methodology The study aims to identify key attributes of coordinated weight loss programmes and elicit patients’ preferences for overweight and obesity therapy in rehabilitation programmes. A self-administered survey measuring attitudes and preferences was conducted in Germany in 2009. Discrete-choice experiment scenarios were developed using a fractional factorial design and results analysed using a random effects logit model. Results N=110 patients completed the questionnaire, 51.82% of these were male, the mean age was 53.05 years and mean body mass index was 33.54 kg/m2 (SD 7.73). A total of 823 choices could be included in the final estimation. The most important aspects for the respondents’ selection were care coordination (coefficient 1.473; SE 0.185) and individual therapy (coefficient 1.446; SE 0.188). The aspect ‘infrastructure of care’ (coefficient 0.570; SE 0.175) was less relevant. All attributes led to significant coefficients. Conclusion Patients value coordination of care and individual therapy most highly. So weight reduction therapy should enable patients to receive a structured, coordinated and interpersonal therapy that is tailored to their personal needs, behaviour and circumstances. Patients are willing to forego infrastructure quality in favour of better coordination and structure in their therapy. PMID:24179457

A Discrete Choice Experiment to Elicit Patient Willingness to Pay for Attributes of Treatment-Induced Symptom Relief in Comorbid Insomnia

PubMed Central

Roy, Anuja N.; Madhavan, S. Suresh; Lloyd, Andrew

2016-01-01

Purpose Insomnia is a burdensome, commonly comorbid condition. How patients value various aspects of the safety and efficacy of available drugs has not been studied. The aim of the present study was to quantify patient-rated utility by studying willingness to pay (WTP) for attributes of symptom relief via a discrete choice experiment (DCE). Methodology Adult primary care patients (West Virginia University Hospital) with comorbid insomnia were enrolled. The attributes and levels examined were sleep onset latency (SOL; 10, 20, 30 minutes), awakenings (1, 2, 3), wake time after sleep onset (WASO; 15, 45, 60 minutes), total sleep time (TST; 6, 7, 8 hours), hangover (none, mild, moderate), FDA-approved duration of use (short term, not restricted to short term, no restrictions), and out-of-pocket cost per month ($20, $35, $50). Willingness to pay (WTP) data were analyzed using a random effects binary logistic regression model. Results A total of 82 patients completed the DCE (74 analyzed). SOL, WASO, TST, and cost were all found to predict treatment choice. Higher values of SOL, WASO, and cost resulted in decreased preference for a particular treatment, while higher TST predicted increased preference. Modeling revealed an estimated marginal WTP of $66.69 for an example product that improved SOL by 10 minutes, reduced WASO by 15 minutes, and improved TST by 1 hour. Conclusion Patient WTP for symptomatic relief in insomnia can help clinicians fine-tune interventions based on patient preferences, provide evidence for drug formulary and reimbursement decisions, and potentially guide the development of novel drugs. PMID:26489177

Ordinal preference elicitation methods in health economics and health services research: using discrete choice experiments and ranking methods.

PubMed

Ali, Shehzad; Ronaldson, Sarah

2012-09-01

The predominant method of economic evaluation is cost-utility analysis, which uses cardinal preference elicitation methods, including the standard gamble and time trade-off. However, such approach is not suitable for understanding trade-offs between process attributes, non-health outcomes and health outcomes to evaluate current practices, develop new programmes and predict demand for services and products. Ordinal preference elicitation methods including discrete choice experiments and ranking methods are therefore commonly used in health economics and health service research. Cardinal methods have been criticized on the grounds of cognitive complexity, difficulty of administration, contamination by risk and preference attitudes, and potential violation of underlying assumptions. Ordinal methods have gained popularity because of reduced cognitive burden, lower degree of abstract reasoning, reduced measurement error, ease of administration and ability to use both health and non-health outcomes. The underlying assumptions of ordinal methods may be violated when respondents use cognitive shortcuts, or cannot comprehend the ordinal task or interpret attributes and levels, or use 'irrational' choice behaviour or refuse to trade-off certain attributes. CURRENT USE AND GROWING AREAS: Ordinal methods are commonly used to evaluate preference for attributes of health services, products, practices, interventions, policies and, more recently, to estimate utility weights. AREAS FOR ON-GOING RESEARCH: There is growing research on developing optimal designs, evaluating the rationalization process, using qualitative tools for developing ordinal methods, evaluating consistency with utility theory, appropriate statistical methods for analysis, generalizability of results and comparing ordinal methods against each other and with cardinal measures.

Exploring preferences for symptom management in primary care: a discrete choice experiment using a questionnaire survey.

PubMed

McAteer, Anne; Yi, Deokhee; Watson, Verity; Norwood, Patricia; Ryan, Mandy; Hannaford, Philip C; Elliott, Alison M

2015-07-01

Symptoms are important drivers for the use of primary care services. Strategies aimed at shifting the focus away from the GP have broadened the range of primary healthcare available. To explore preferences for managing symptoms and investigate trade-offs that the public are willing to make when deciding between different primary care services. UK-wide postal questionnaire survey of 1370 adults. A discrete choice experiment examined management preferences for three symptoms of differing seriousness (diarrhoea, dizziness, and chest pain). Willingness-to-pay estimates compared preferences between symptoms, and by sex, age, and income. Preferences differed significantly between symptoms. 'Self-care' was the preferred action for diarrhoea and 'consulting a GP' for dizziness and chest pain. 'Waiting time' and 'chance of a satisfactory outcome' were important factors for all three symptoms, although their relative importance differed. Broadly, people were more prepared to wait longer and less prepared to trade a good chance of a satisfactory outcome for symptoms rated as more serious. Generally, preferences within subgroups followed similar patterns as for the whole sample, although there were differences in the relative strength of preferences. Despite increased choices in primary care, 'traditional' actions of 'self-care' for minor symptoms and 'GP consultation' for more serious symptoms were preferred. The present findings suggest, however, that people may be willing to trade between different health services, particularly for less serious symptoms. Understanding the relative importance of different factors may help inform interventions aimed at changing management behaviour or improving services. © British Journal of General Practice 2015.

Preference for practice: a Danish study on young doctors' choice of general practice using a discrete choice experiment.

PubMed

Pedersen, Line Bjørnskov; Gyrd-Hansen, Dorte

2014-07-01

This study examines the preferences of general practitioners (GPs) in training for organizational characteristics in general practice with focus on aspects that can mitigate problems with GP shortages. A discrete choice experiment was used to investigate preferences for the attributes practice type, number of GPs in general practice, collaboration with other practices, change in weekly working hours (administrative versus patient related), and change in yearly surplus. In May 2011, all doctors actively engaged in the family medicine program in Denmark were invited to participate in a web-based survey. A total of 485 GPs in training responded to the questionnaire, resulting in a response rate of 56%. A mixed logit model showed that GPs in training prefer to work in smaller shared practices (2 GPs). This stands in contrast to the preferences of current GPs. Hence, a generational change in the GP population is likely to introduce more productive practice forms, and problems with GP shortages are likely to be mitigated over the coming years. Results further showed that a majority of the respondents are willing to work in larger shared practices (with 3-4 GPs) if they receive an increase in surplus (approximately 50,000 DKK/6,719 EUR per year) and that they may be willing to take in more patient-related work if the increase in surplus is sufficient (approximately 200,000 DKK/26,875 EUR per year for 5 extra hours per week). Monetary incentives may therefore be an effective tool for further improving productivity.

Financial incentives to discontinue long-term benzodiazepine use: a discrete choice experiment investigating patient preferences and willingness to participate

PubMed Central

Marti, Joachim; Bachhuber, Marcus; Feingold, Jordyn; Meads, David; Richards, Michael; Hennessy, Sean

2017-01-01

Objectives Investigate the acceptability of financial incentives for initiating a medically supervised benzodiazepine discontinuation programme among people with long-term benzodiazepine use and to identify programme features that influence willingness to participate. Methods We conducted a discrete choice experiment in which we presented a variety of incentive-based programs to a sample of older adults with long-term benzodiazepine use identified using the outpatient electronic health record of a university-owned health system. We studied four programme variables: incentive amount for initiating the programme, incentive amount for successful benzodiazepine discontinuation, lottery versus certain payment and whether partial payment was given for dose reduction. Respondents reported their willingness to participate in the programmes and additional information was collected on demographics, history of use and anxiety symptoms. Results The overall response rate was 28.4%. Among the 126 respondents, all four programme variables influenced stated preferences. Respondents strongly preferred guaranteed cash-based incentives as opposed to a lottery, and the dollar amount of both the starting and conditional incentives had a substantial impact on choice. Willingness to participate increased with the amount of conditional incentive. Programme participation also varied by gender, duration of use and income. Conclusions Participation in an incentive-based benzodiazepine discontinuation programme might be relatively low, but is modifiable by programme variables including incentive amounts. These results will be helpful to inform the design of future trials of benzodiazepine discontinuation programmes. Further research is needed to assess the financial viability and potential cost-effectiveness of such economic incentives. PMID:28988167

Measuring the loss of consumer choice in mandatory health programmes using discrete choice experiments.

PubMed

Parkinson, Bonny; Goodall, Stephen; Norman, Richard

2013-04-01

Economic evaluation of mandatory health programmes generally do not consider the utility impact of a loss of consumer choice upon implementation, despite evidence suggesting that consumers do value having the ability to choose. The primary aim of this study was to explore whether the utility impact of a loss of consumer choice from implementing mandatory health programmes can be measured using discrete choice experiments (DCEs). Three case studies were used to test the methodology: fortification of bread-making flour with folate, mandatory influenza vaccination of children, and the banning of trans-fats. Attributes and levels were developed from a review of the literature. An orthogonal, fractional factorial design was used to select the profiles presented to respondents to allow estimation of main effects. Overall, each DCE consisted of 64 profiles which were allocated to four versions of 16 profiles. Each choice task compared two profiles, one being voluntary and the other being mandatory, plus a 'no policy' option, thus each respondent was presented with eight choice tasks. For each choice task, respondents were asked which health policy they most preferred and least preferred. Data was analysed using a mixed logit model with correlated coefficients (200 Halton draws). The compensating variation required for introducing a programme on a mandatory basis (versus achieving the same health impacts with a voluntary programme) that holds utility constant was estimated. Responses were provided by 535 participants (a response rate of 83 %). For the influenza vaccination and folate fortification programmes, the results suggested that some level of compensation may be required for introducing the programme on a mandatory basis. Introducing a mandatory influenza vaccination programme required the highest compensation (Australian dollars [A$] 112.75, 95 % CI -60.89 to 286.39) compared with folate fortification (A$18.05, 95 % CI -3.71 to 39.80). No compensation was required for introducing the trans-fats programme (-A$0.22, 95 % CI -6.24 to 5.80) [year 2010 values]. In addition to the type of mandatory health programme, the compensation required was also found to be dependent on a number of other factors. In particular, the study found an association between the compensation required and stronger libertarian preferences. DCEs can be used to measure the utility impact of a loss of consumer choice. Excluding the utility impact of a loss of consumer choice from an economic evaluation taking a societal perspective may result in a sub-optimal, or incorrect, funding decision.

Stated choice for transportation demand management models : using a disaggregate truth set to study predictive validity

DOT National Transportation Integrated Search

1997-01-01

Discrete choice models have expanded the ability of transportation planners to forecast future trends. Where new services or policies are proposed, the stated-choice approach can provide an objective basis for forecasts. Stated-choice models are subj...

When you can't have the cake and eat it too: a study of medical doctors' priorities in complex choice situations.

PubMed

Carlsen, Benedicte; Hole, Arne Risa; Kolstad, Julie Riise; Norheim, Ole Frithjof

2012-12-01

Available literature provides little insight into medical doctors' prescription choices when they are required to make complex trade-offs between different concerns such as treatment effect, costs, and patient preferences simultaneously. This study investigates this issue. It is based on a Discrete Choice Experiment (DCE) conducted with 571 Norwegian doctors, where the DCE captures preferences for medications described along five dimensions important for both clinical decision-making and prioritisation in the health sector. Although effectiveness is the most important determinant of choice in our study, doctors also put considerable weight on patients' preferences and on avoiding high total costs. The probability of choosing a particular medication increases when doctors have a positive experience with the medication. GPs value high clinical effectiveness less than hospital consultants do. They are also less concerned with patient preferences. For both groups of doctors it turns out that they are willing to make difficult trade-offs between attributes they are often assumed not to be willing to compromise on, like effectiveness or patient preferences, and cost measures - given that they have proper information about these attributes. Copyright © 2012 Elsevier Ltd. All rights reserved.

Probabilistic choice models in health-state valuation research: background, theories, assumptions and applications.

PubMed

Arons, Alexander M M; Krabbe, Paul F M

2013-02-01

Interest is rising in measuring subjective health outcomes, such as treatment outcomes that are not directly quantifiable (functional disability, symptoms, complaints, side effects and health-related quality of life). Health economists in particular have applied probabilistic choice models in the area of health evaluation. They increasingly use discrete choice models based on random utility theory to derive values for healthcare goods or services. Recent attempts have been made to use discrete choice models as an alternative method to derive values for health states. In this article, various probabilistic choice models are described according to their underlying theory. A historical overview traces their development and applications in diverse fields. The discussion highlights some theoretical and technical aspects of the choice models and their similarity and dissimilarity. The objective of the article is to elucidate the position of each model and their applications for health-state valuation.

Estimation of Dynamic Discrete Choice Models by Maximum Likelihood and the Simulated Method of Moments

PubMed Central

Eisenhauer, Philipp; Heckman, James J.; Mosso, Stefano

2015-01-01

We compare the performance of maximum likelihood (ML) and simulated method of moments (SMM) estimation for dynamic discrete choice models. We construct and estimate a simplified dynamic structural model of education that captures some basic features of educational choices in the United States in the 1980s and early 1990s. We use estimates from our model to simulate a synthetic dataset and assess the ability of ML and SMM to recover the model parameters on this sample. We investigate the performance of alternative tuning parameters for SMM. PMID:26494926

Developing attributes and attribute-levels for a discrete choice experiment on micro health insurance in rural Malawi

PubMed Central

2014-01-01

Background Discrete choice experiments (DCEs) are attribute-driven experimental techniques used to elicit stakeholders’ preferences to support the design and implementation of policy interventions. The validity of a DCE, therefore, depends on the appropriate specification of the attributes and their levels. There have been recent calls for greater rigor in implementing and reporting on the processes of developing attributes and attribute-levels for discrete choice experiments (DCEs). This paper responds to such calls by carefully reporting a systematic process of developing micro health insurance attributes and attribute-levels for the design of a DCE in rural Malawi. Methods Conceptual attributes and attribute-levels were initially derived from a literature review which informed the design of qualitative data collection tools to identify context specific attributes and attribute-levels. Qualitative data was collected in August-September 2012 from 12 focus group discussions with community residents and 8 in-depth interviews with health workers. All participants were selected according to stratified purposive sampling. The material was tape-recorded, fully transcribed, and coded by three researchers to identify context-specific attributes and attribute-levels. Expert opinion was used to scale down the attributes and levels. A pilot study confirmed the appropriateness of the selected attributes and levels for a DCE. Results First, a consensus, emerging from an individual level analysis of the qualitative transcripts, identified 10 candidate attributes. Levels were assigned to all attributes based on data from transcripts and knowledge of the Malawian context, derived from literature. Second, through further discussions with experts, four attributes were discarded based on multiple criteria. The 6 remaining attributes were: premium level, unit of enrollment, management structure, health service benefit package, transportation coverage and copayment levels. A final step of revision and piloting confirmed that the retained attributes satisfied the credibility criteria of DCE attributes. Conclusion This detailed description makes our attribute development process transparent, and provides the reader with a basis to assess the rigor of this stage of constructing the DCE. This paper contributes empirical evidence to the limited methodological literature on attributes and levels development for DCE, thereby providing further empirical guidance on the matter, specifically within rural communities of low- and middle-income countries. PMID:24884920

How do women trade-off benefits and risks in chemotherapy treatment decisions based on gene expression profiling for early-stage breast cancer? A discrete choice experiment.

PubMed

Marshall, Deborah A; Deal, Ken; Bombard, Yvonne; Leighl, Natasha; MacDonald, Karen V; Trudeau, Maureen

2016-06-02

Gene expression profiling (GEP) of tumours informs baseline risk prediction, potentially affecting adjuvant chemotherapy decisions for women with early-stage breast cancer. Since only 15% will experience a recurrence, concerns have been raised about potential harms from overtreatment and high GEP costs in publicly funded healthcare systems. We aimed to estimate preferences and personal utility of GEP testing information and benefit-risk trade-offs in chemotherapy treatment decisions. Based on literature review and findings from our qualitative research (focus groups, interviews with patients with breast cancer and medical oncologists), we developed a discrete choice experiment (DCE) survey and administered it via an internet panel. The DCE included 12 choice tasks with 5 attributes and 3 alternatives considering orthogonality, D-efficiency and level balance. The DCE survey was administered to 1004 Canadian women from the general population. Preferences were analysed using conditional logit and hierarchical Bayes and evaluated for goodness of fit. We conducted simulation analyses for alternative scenarios. GEP test score indicating likely benefit from chemotherapy was the most important attribute. Doctor's clinical estimate of the risk of cancer returning, trust in your cancer doctor and side effects of chemotherapy (temporary and permanent) were relatively less important but showed significant differences among levels. In the scenario analyses, 78% were likely to choose chemotherapy in a high-risk scenario, 55% in a moderate-risk scenario and 33% in a low-risk scenario, with the other attributes held constant. A high GEP score was more important in influencing the choice of chemotherapy for those at intermediate clinical risk. GEP testing information influences chemotherapy treatment decisions in early-stage breast cancer and varies depending on clinical risk. Clinicians should be aware of these differences and tailor the use of GEP testing accordingly. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Discrete choice modeling of season choice for Minnesota turkey hunters

USGS Publications Warehouse

Schroeder, Susan A.; Fulton, David C.; Cornicelli, Louis; Merchant, Steven S.

2018-01-01

Recreational turkey hunting exemplifies the interdisciplinary nature of modern wildlife management. Turkey populations in Minnesota have reached social or biological carrying capacities in many areas, and changes to turkey hunting regulations have been proposed by stakeholders and wildlife managers. This study employed discrete stated choice modeling to enhance understanding of turkey hunter preferences about regulatory alternatives. We distributed mail surveys to 2,500 resident turkey hunters. Results suggest that, compared to season structure and lotteries, additional permits and level of potential interference from other hunters most influenced hunter preferences for regulatory alternatives. Low hunter interference was preferred to moderate or high interference. A second permit issued only to unsuccessful hunters was preferred to no second permit or permits for all hunters. Results suggest that utility is not strictly defined by harvest or an individual's material gain but can involve preference for other outcomes that on the surface do not materially benefit an individual. Discrete stated choice modeling offers wildlife managers an effective way to assess constituent preferences related to new regulations before implementing them. 

Survival or Mortality: Does Risk Attribute Framing Influence Decision-Making Behavior in a Discrete Choice Experiment?

PubMed

Veldwijk, Jorien; Essers, Brigitte A B; Lambooij, Mattijs S; Dirksen, Carmen D; Smit, Henriette A; de Wit, G Ardine

2016-01-01

To test how attribute framing in a discrete choice experiment (DCE) affects respondents' decision-making behavior and their preferences. Two versions of a DCE questionnaire containing nine choice tasks were distributed among a representative sample of the Dutch population aged 55 to 65 years. The DCE consisted of four attributes related to the decision regarding participation in genetic screening for colorectal cancer (CRC). The risk attribute included was framed positively as the probability of surviving CRC and negatively as the probability of dying from CRC. Panel mixed-logit models were used to estimate the relative importance of the attributes. The data of the positively and negatively framed DCE were compared on the basis of direct attribute ranking, dominant decision-making behavior, preferences, and importance scores. The majority (56%) of the respondents ranked survival as the most important attribute in the positively framed DCE, whereas only a minority (8%) of the respondents ranked mortality as the most important attribute in the negatively framed DCE. Respondents made dominant choices based on survival significantly more often than based on mortality. The framing of the risk attribute significantly influenced all attribute-level estimates and resulted in different preference structures among respondents in the positively and negatively framed data set. Risk framing affects how respondents value the presented risk. Positive risk framing led to increased dominant decision-making behavior, whereas negative risk framing led to risk-seeking behavior. Attribute framing should have a prominent part in the expert and focus group interviews, and different types of framing should be used in the pilot version of DCEs as well as in actual DCEs to estimate the magnitude of the effect of choosing different types of framing. Copyright © 2016 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Eliciting preferences for waterpipe tobacco smoking using a discrete choice experiment: implications for product regulation.

PubMed

Salloum, Ramzi G; Maziak, Wasim; Hammond, David; Nakkash, Rima; Islam, Farahnaz; Cheng, Xi; Thrasher, James F

2015-09-09

Waterpipe smoking is highly prevalent among university students, and has been increasing in popularity despite mounting evidence showing it is harmful to health. The aim of this study was to measure preferences for waterpipe smoking and determine which product characteristics are most important to smokers. A large university in the Southeastern USA. Adult waterpipe smokers attending the university (N=367). Participants completed an Internet-based discrete choice experiment to reveal their preferences for, and trade-offs between, the attributes of hypothetical waterpipe smoking sessions. Participants were presented with waterpipe lounge menus, each with three fruit-flavoured options and one tobacco flavoured option, in addition to an opt out option. Nicotine content and price were provided for each choice. Participants were randomised to either receive menus with a text-only health-warning message or no message. Multinomial and nested logit models were used to estimate the impact on consumer choice of attributes and between-subject assignment of health warnings respectively. On average, participants preferred fruit-flavoured varieties to tobacco flavour. They were averse to options labelled with higher nicotine content. Females and non-smokers of cigarettes were more likely than their counterparts to prefer flavoured and nicotine-free varieties. Participants exposed to a health warning were more likely to opt out. Fruit-flavoured tobacco and lower nicotine content labels, two strategies widely used by the industry, increase the demand for waterpipe smoking among young adults. Waterpipe-specific regulation should limit the availability of flavoured waterpipe tobacco and require accurate labelling of constituents. Waterpipe-specific tobacco control regulation, along with research to inform policy, is required to curb this emerging public health threat. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Rural Clinician Scarcity and Job Preferences of Doctors and Nurses in India: A Discrete Choice Experiment

PubMed Central

Rao, Krishna D.; Ryan, Mandy; Shroff, Zubin; Vujicic, Marko; Ramani, Sudha; Berman, Peter

2013-01-01

The scarcity of rural doctors has undermined the ability of health systems in low and middle-income countries like India to provide quality services to rural populations. This study examines job preferences of doctors and nurses to inform what works in terms of rural recruitment strategies. Job acceptance of different strategies was compared to identify policy options for increasing the availability of clinical providers in rural areas. In 2010 a Discrete Choice Experiment was conducted in India. The study sample included final year medical and nursing students, and in-service doctors and nurses serving at Primary Health Centers. Eight job attributes were identified and a D-efficient fractional factorial design was used to construct pairs of job choices. Respondent acceptance of job choices was analyzed using multi-level logistic regression. Location mattered; jobs in areas offering urban amenities had a high likelihood of being accepted. Higher salary had small effect on doctor, but large effect on nurse, acceptance of rural jobs. At five times current salary levels, 13% (31%) of medical students (doctors) were willing to accept rural jobs. At half this level, 61% (52%) of nursing students (nurses) accepted a rural job. The strategy of reserving seats for specialist training in exchange for rural service had a large effect on job acceptance among doctors, nurses and nursing students. For doctors and nurses, properly staffed and equipped health facilities, and housing had small effects on job acceptance. Rural upbringing was not associated with rural job acceptance. Incentivizing doctors for rural service is expensive. A broader strategy of substantial salary increases with improved living, working environment, and education incentives is necessary. For both doctors and nurses, the usual strategies of moderate salary increases, good facility infrastructure, and housing will not be effective. Non-physician clinicians like nurse-practitioners offer an affordable alternative for delivering rural health care. PMID:24376621

Women’s preferences for alternative financial incentive schemes for breastfeeding: A discrete choice experiment

PubMed Central

Anokye, Nana; de Bekker-Grob, Esther W.; Higgins, Ailish; Relton, Clare; Strong, Mark; Fox-Rushby, Julia

2018-01-01

Background Increasing breastfeeding rates have been associated with reductions in disease in babies and mothers as well as in related costs. ‘Nourishing Start for Health (NoSH)’, a financial incentive scheme has been proposed as a potentially effective way to increase both the number of mothers breastfeeding and duration of breastfeeding. Aims To establish women’s relative preferences for different aspects of a financial incentive scheme for breastfeeding and to identify importance of scheme characteristics on probability on participation in an incentive scheme. Methods A discrete choice experiment (DCE) obtained information on alternative specifications of the NoSH scheme designed to promote continued breastfeeding duration until at least 6 weeks after birth. Four attributes framed alternative scheme designs: value of the incentive; minimum breastfeeding duration required to receive incentive; method of verifying breastfeeding; type of incentive. Three versions of the DCE questionnaire, each containing 8 different choice sets, provided 24 choice sets for analysis. The questionnaire was mailed to 2,531 women in the South Yorkshire Cohort (SYC) aged 16–45 years in IMD quintiles 3–5. The analytic approach considered conditional and mixed effects logistic models to account for preference heterogeneity that may be associated with a variation in effects mediated by respondents’ characteristics. Results 564 women completed the questionnaire and a response rate of 22% was achieved. Most of the included attributes were found to affect utility and therefore the probability to participate in the incentive scheme. Higher rewards were preferred, although the type of incentive significantly affected women’s preferences on average. We found evidence for preference heterogeneity based on individual characteristics that mediated preferences for an incentive scheme.Conclusions Although participants’ opinion in our sample was mixed, financial incentives for breastfeeding may be an acceptable and effective instrument to change behaviour. However, individual characteristics could mediate the effect and should therefore be considered when developing and targeting future interventions. PMID:29649245

What influences where they seek care? Caregivers’ preferences for under-five child healthcare services in urban slums of Malawi: A discrete choice experiment

PubMed Central

Guda Obse, Amarech; Darker, Catherine; Biesma, Regien

2018-01-01

Access to and utilisation of quality healthcare promotes positive child health outcomes. However, to be optimally utilised, the healthcare system needs to be responsive to the expectations of the population it serves. Health systems in many sub-Saharan African countries, including Malawi, have historically focused on promoting access to health services by the rural poor. However, in the context of increasing urbanisation and consequent proliferation of urban slums, promoting health of children under five years of age in these settings is a public health imperative. We conducted a discrete choice experiment to determine the relative importance of health facility factors in seeking healthcare for childhood illnesses in urban slums of Malawi. Caregivers of children under five years of age were presented with choice cards that depicted two hypothetical health facilities using six health facility attributes: availability of medicines and supplies, thoroughness of physical examination of the child, attitude of health workers, cost, distance, and waiting time. Caregivers were asked to indicate the health facility they would prefer to use. A mixed logit model was used to estimate the relative importance of and willingness to pay (WTP) for health facility attributes. Attributes with greatest influence on choice were: availability of medicines and supplies (β = 0.842, p<0.001) and thorough examination of the child (β = 0.479, p <0.001) with WTP of MK3698.32 ($11) (95% CI: $8–$13) and MK2049.13 ($6) (95% CI: $3–$9) respectively. Respondents were willing to pay 1.8 and 2.4 times more for medicine availability over thorough examination and positive attitude of health workers respectively. Therefore, strengthening health service delivery system through investment in sustained availability of essential medicines and supplies, sufficient and competent health workforce with positive attitude and clinical discipline to undertake thorough examination, and reductions in waiting times have the potential to improve child healthcare utilization in the urban slums. PMID:29351299

What influences where they seek care? Caregivers' preferences for under-five child healthcare services in urban slums of Malawi: A discrete choice experiment.

PubMed

Lungu, Edgar Arnold; Guda Obse, Amarech; Darker, Catherine; Biesma, Regien

2018-01-01

Access to and utilisation of quality healthcare promotes positive child health outcomes. However, to be optimally utilised, the healthcare system needs to be responsive to the expectations of the population it serves. Health systems in many sub-Saharan African countries, including Malawi, have historically focused on promoting access to health services by the rural poor. However, in the context of increasing urbanisation and consequent proliferation of urban slums, promoting health of children under five years of age in these settings is a public health imperative. We conducted a discrete choice experiment to determine the relative importance of health facility factors in seeking healthcare for childhood illnesses in urban slums of Malawi. Caregivers of children under five years of age were presented with choice cards that depicted two hypothetical health facilities using six health facility attributes: availability of medicines and supplies, thoroughness of physical examination of the child, attitude of health workers, cost, distance, and waiting time. Caregivers were asked to indicate the health facility they would prefer to use. A mixed logit model was used to estimate the relative importance of and willingness to pay (WTP) for health facility attributes. Attributes with greatest influence on choice were: availability of medicines and supplies (β = 0.842, p<0.001) and thorough examination of the child (β = 0.479, p <0.001) with WTP of MK3698.32 ($11) (95% CI: $8-$13) and MK2049.13 ($6) (95% CI: $3-$9) respectively. Respondents were willing to pay 1.8 and 2.4 times more for medicine availability over thorough examination and positive attitude of health workers respectively. Therefore, strengthening health service delivery system through investment in sustained availability of essential medicines and supplies, sufficient and competent health workforce with positive attitude and clinical discipline to undertake thorough examination, and reductions in waiting times have the potential to improve child healthcare utilization in the urban slums.

Household Size and the Decision to Purchase Health Insurance in Cambodia: Results of a Discrete-Choice Experiment with Scale Adjustment.

PubMed

Ozawa, Sachiko; Grewal, Simrun; Bridges, John F P

2016-04-01

Community-based health insurance (CBHI) schemes have been introduced in low- and middle-income countries to increase health service utilization and provide financial protection from high healthcare expenditures. We assess the impact of household size on decisions to enroll in CBHI and demonstrate how to correct for group disparity in scale (i.e. variance differences). A discrete choice experiment was conducted across five CBHI attributes. Preferences were elicited through forced-choice paired comparison choice tasks designed based on D-efficiency. Differences in preferences were examined between small (1-4 family members) and large (5-12 members) households using conditional logistic regression. Swait and Louviere test was used to identify and correct for differences in scale. One-hundred and sixty households were surveyed in Northwest Cambodia. Increased insurance premium was associated with disutility [odds ratio (OR) 0.61, p < 0.01], while significant increase in utility was noted for higher hospital fee coverage (OR 10.58, p < 0.01), greater coverage of travel and meal costs (OR 4.08, p < 0.01), and more frequent communication with the insurer (OR 1.33, p < 0.01). While the magnitude of preference for hospital fee coverage appeared larger for the large household group (OR 14.15) compared to the small household group (OR 8.58), differences in scale were observed (p < 0.05). After adjusting for scale (k, ratio of scale between large to small household groups = 1.227, 95 % confidence interval 1.002-1.515), preference differences by household size became negligible. Differences in stated preferences may be due to scale, or variance differences between groups, rather than true variations in preference. Coverage of hospital fees, travel and meal costs are given significant weight in CBHI enrollment decisions regardless of household size. Understanding how community members make decisions about health insurance can inform low- and middle-income countries' paths towards universal health coverage.

Net costs of health worker rural incentive packages: an example from the Lao People's Democratic Republic.

PubMed

Keuffel, Eric; Jaskiewicz, Wanda; Paphassarang, Chanthakhath; Tulenko, Kate

2013-11-01

Many developing countries are examining whether to institute incentive packages that increase the share of health workers who opt to locate in rural settings; however, uncertainty exists with respect to the expected net cost (or benefit) from these packages. We utilize the findings from the discrete choice experiment surveys applied to students training to be health professionals and costing analyses in Lao People's Democratic Republic to model the anticipated effect of incentive packages on new worker location decisions and direct costs. Incorporating evidence on health worker density and health outcomes, we then estimate the expected 5-year net cost (or benefit) of each incentive packages for 3 health worker cadres--physicians, nurses/midwives, and medical assistants. Under base case assumptions, the optimal incentive package for each cadre produced a 5-year net benefit (maximum net benefit for physicians: US$ 44,000; nurses/midwives: US$ 5.6 million; medical assistants: US$ 485,000). After accounting for health effects, the expected net cost of select incentive packages would be substantially less than the original estimate of direct costs. In the case of Lao People's Democratic Republic, incentive packages that do not invest in capital-intensive components generally should produce larger net benefits. Combining discrete choice experiment surveys, costing surveys and cost-benefit analysis methods may be replicated by other developing countries to calculate whether health worker incentive packages are viable policy options.

Using discrete choice experiments within a cost-benefit analysis framework: some considerations.

PubMed

McIntosh, Emma

2006-01-01

A great advantage of the stated preference discrete choice experiment (SPDCE) approach to economic evaluation methodology is its immense flexibility within applied cost-benefit analyses (CBAs). However, while the use of SPDCEs in healthcare has increased markedly in recent years there has been a distinct lack of equivalent CBAs in healthcare using such SPDCE-derived valuations. This article outlines specific issues and some practical suggestions for consideration relevant to the development of CBAs using SPDCE-derived benefits. The article shows that SPDCE-derived CBA can adopt recent developments in cost-effectiveness methodology including the cost-effectiveness plane, appropriate consideration of uncertainty, the net-benefit framework and probabilistic sensitivity analysis methods, while maintaining the theoretical advantage of the SPDCE approach. The concept of a cost-benefit plane is no different in principle to the cost-effectiveness plane and can be a useful tool for reporting and presenting the results of CBAs.However, there are many challenging issues to address for the advancement of CBA methodology using SPCDEs within healthcare. Particular areas for development include the importance of accounting for uncertainty in SPDCE-derived willingness-to-pay values, the methodology of SPDCEs in clinical trial settings and economic models, measurement issues pertinent to using SPDCEs specifically in healthcare, and the importance of issues such as consideration of the dynamic nature of healthcare and the resulting impact this has on the validity of attribute definitions and context.

Cognitive overload? An exploration of the potential impact of cognitive functioning in discrete choice experiments with older people in health care.

PubMed

Milte, Rachel; Ratcliffe, Julie; Chen, Gang; Lancsar, Emily; Miller, Michelle; Crotty, Maria

2014-07-01

This exploratory study sought to investigate the effect of cognitive functioning on the consistency of individual responses to a discrete choice experiment (DCE) study conducted exclusively with older people. A DCE to investigate preferences for multidisciplinary rehabilitation was administered to a consenting sample of older patients (aged 65 years and older) after surgery to repair a fractured hip (N = 84). Conditional logit, mixed logit, heteroscedastic conditional logit, and generalized multinomial logit regression models were used to analyze the DCE data and to explore the relationship between the level of cognitive functioning (specifically the absence or presence of mild cognitive impairment as assessed by the Mini-Mental State Examination) and preference and scale heterogeneity. Both the heteroscedastic conditional logit and generalized multinomial logit models indicated that the presence of mild cognitive impairment did not have a significant effect on the consistency of responses to the DCE. This study provides important preliminary evidence relating to the effect of mild cognitive impairment on DCE responses for older people. It is important that further research be conducted in larger samples and more diverse populations to further substantiate the findings from this exploratory study and to assess the practicality and validity of the DCE approach with populations of older people. Copyright © 2014 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Weighing the Social and Ethical Considerations of Maternal-Fetal Surgery.

PubMed

Antiel, Ryan M; Flake, Alan W; Collura, Christopher A; Johnson, Mark P; Rintoul, Natalie E; Lantos, John D; Curlin, Farr A; Tilburt, Jon C; Brown, Stephen D; Feudtner, Chris

2017-12-01

The ethics of maternal-fetal surgery involves weighing the importance of potential benefits, risks, and other consequences involving the pregnant woman, fetus, and other family members. We assessed clinicians' ratings of the importance of 9 considerations relevant to maternal-fetal surgery. This study was a discrete choice experiment contained within a 2015 national mail-based survey of 1200 neonatologists, pediatric surgeons, and maternal-fetal medicine physicians, with latent class analysis subsequently used to identify groups of physicians with similar ratings. Of 1176 eligible participants, 660 (56%) completed the discrete choice experiment. The highest-ranked consideration was of neonatal benefits, which was followed by consideration of the risk of maternal complications. By using latent class analysis, we identified 4 attitudinal groups with similar patterns of prioritization: "fetocentric" ( n = 232), risk-sensitive ( n = 197), maternal autonomy ( n = 167), and family impact and social support ( n = 64). Neonatologists were more likely to be in the fetocentric group, whereas surgeons were more likely to be in the risk-sensitive group, and maternal-fetal medicine physicians made up the largest percentage of the family impact and social support group. Physicians vary in how they weigh the importance of social and ethical considerations regarding maternal-fetal surgery. Understanding these differences may help prevent or mitigate disagreements or tensions that may arise in the management of these patients. Copyright © 2017 by the American Academy of Pediatrics.

Attitudes toward Infection Prophylaxis in Pediatric Oncology: A Qualitative Approach

PubMed Central

Diorio, Caroline; Tomlinson, Deborah; Boydell, Katherine M.; Regier, Dean A.; Ethier, Marie-Chantal; Alli, Amanda; Alexander, Sarah; Gassas, Adam; Taylor, Jonathan; Kellow, Charis; Mills, Denise; Sung, Lillian

2012-01-01

Background The risks and benefits of infection prophylaxis are uncertain in children with cancer and thus, preferences should be considered in decision making. The purpose of this report was to describe the attitudes of parents, children and healthcare professionals to infection prophylaxis in pediatric oncology. Methods The study was completed in three phases: 1) An initial qualitative pilot to identify the main attributes influencing the decision to use infection prophylaxis, which were then incorporated into a discrete choice experiment; 2) A think aloud during the discrete choice experiment in which preferences for infection prophylaxis were elicited quantitatively; and 3) In-depth follow up interviews. Interviews were recorded verbatim and analyzed using an iterative, thematic analysis. Final themes were selected using a consensus approach. Results A total of 35 parents, 22 children and 28 healthcare professionals participated. All three groups suggested that the most important factor influencing their decision making was the effect of prophylaxis on reducing the chance of death. Themes of importance to the three groups included antimicrobial resistance, side effects of medications, the financial impact of outpatient prophylaxis and the route and schedule of administration. Conclusion Effect of prophylaxis on risk of death was a key factor in decision making. Other identified factors were antimicrobial resistance, side effects of medication, financial impact and administration details. Better understanding of factors driving decision making for infection prophylaxis will help facilitate future implementation of prophylactic regiments. PMID:23112849

A discrete choice experiment studying students' preferences for scholarships to private medical schools in Japan.

PubMed

Goto, Rei; Kakihara, Hiroaki

2016-02-09

The shortage of physicians in rural areas and in some specialties is a societal problem in Japan. Expensive tuition in private medical schools limits access to them particularly for students from middle- and low-income families. One way to reduce this barrier and lessen maldistribution is to offer conditional scholarships to private medical schools. A discrete choice experiment is carried out on a total of 374 students considering application to medical schools. The willingness to receive a conditional scholarship program to private medical schools is analyzed. The probability of attending private medical schools significantly decreased because of high tuition, a postgraduate obligation to provide a service in specific specialty areas, and the length of time of this obligation. An obligation to provide a service in rural regions had no significant effect on this probability. To motivate non-applicants to private medical schools to enroll in such schools, a decrease in tuition to around 1.2 million yen (US$ 12,000) or less, which is twice that of public schools, was found to be necessary. Further, it was found that non-applicants to private medical schools choose to apply to such schools even with restrictions if they have tuition support at the public school level. Conditional scholarships for private medical schools may widen access to medical education and simultaneously provide incentives to work in insufficiently served areas.

An Australian discrete choice experiment to value eq-5d health states.

PubMed

Viney, Rosalie; Norman, Richard; Brazier, John; Cronin, Paula; King, Madeleine T; Ratcliffe, Julie; Street, Deborah

2014-06-01

Conventionally, generic quality-of-life health states, defined within multi-attribute utility instruments, have been valued using a Standard Gamble or a Time Trade-Off. Both are grounded in expected utility theory but impose strong assumptions about the form of the utility function. Preference elicitation tasks for both are complicated, limiting the number of health states that each respondent can value and, therefore, that can be valued overall. The usual approach has been to value a set of the possible health states and impute values for the remainder. Discrete Choice Experiments (DCEs) offer an attractive alternative, allowing investigation of more flexible specifications of the utility function and greater coverage of the response surface. We designed a DCE to obtain values for EQ-5D health states and implemented it in an Australia-representative online panel (n = 1,031). A range of specifications investigating non-linear preferences with respect to time and interactions between EQ-5D levels were estimated using a random-effects probit model. The results provide empirical support for a flexible utility function, including at least some two-factor interactions. We then constructed a preference index such that full health and death were valued at 1 and 0, respectively, to provide a DCE-based algorithm for Australian cost-utility analyses. Copyright © 2013 John Wiley & Sons, Ltd.

Parents' preferences for vaccinating daughters against human papillomavirus in the Netherlands: a discrete choice experiment.

PubMed

Hofman, Robine; de Bekker-Grob, Esther W; Raat, Hein; Helmerhorst, Theo J M; van Ballegooijen, Marjolein; Korfage, Ida J

2014-05-15

To generate knowledge about potential improvements to human papillomavirus (HPV) vaccination information and organization strategies, we assessed how aspects of HPV vaccination are associated with parents' preferences for their daughters' uptake, and which trade-offs parents are willing to make between these aspects. A discrete choice experiment (DCE) was conducted among parents with a daughter aged 10-12 years. Panel mixed logit regression models were used to determine parents' preferences for vaccination. Trade-offs were quantified between four vaccination programme aspects: degree of protection against cervical cancer, duration of protection, risk of serious side-effects, and age of vaccination. Total response rate was 302/983 (31%). All aspects influenced respondents' preferences for HPV vaccination (p < 0.05). Respondents preferred vaccination at age 14 years instead of at a younger age. Respondents were willing to trade-off 11% of the degree of protection to obtain life-time protection instead of 25 years. To obtain a vaccination with a risk of serious side-effects of 1/750,000 instead of 1/150,000, respondents were willing to trade-off 21%. Uptake may rise if the age ranges for free HPV vaccinations are broadened. Based on the trade-offs parents were willing to make, we conclude that uptake would increase if new evidence indicated outcomes are better than are currently understood, particularly for degree and duration of protection.

Facilitating the implementation of pharmacokinetic-guided dosing of prophylaxis in haemophilia care by discrete choice experiment.

PubMed

Lock, J; de Bekker-Grob, E W; Urhan, G; Peters, M; Meijer, K; Brons, P; van der Meer, F J M; Driessens, M H E; Collins, P W; Fijnvandraat, K; Leebeek, F W G; Cnossen, M H

2016-01-01

Patients', parents' and providers' preferences with regard to medical innovations may have a major impact on their implementation. To evaluate barriers and facilitators for individualized pharmacokinetic (PK)-guided dosing of prophylaxis in haemophilia patients, parents of young patients, and treating professionals by discrete choice experiment (DCE) questionnaire. The study population consisted of patients with haemophilia currently or previously on prophylactic treatment with factor concentrate (n = 114), parents of patients aged 12-18 years (n = 19) and haemophilia professionals (n = 91). DCE data analysis was performed, taking preference heterogeneity into account. Overall, patients and parents, and especially professionals were inclined to opt for PK-guided dosing of prophylaxis. In addition, if bleeding was consequently reduced, more frequent infusions were acceptable. However, daily dosing remained an important barrier for all involved. 'Reduction of costs for society' was a facilitator for implementation in all groups. To achieve implementation of individualized PK-guided dosing of prophylaxis in haemophilia, reduction of bleeding risk and reduction of costs for society should be actively discussed as they are motivating for implementation; daily dosing is still reported to be a barrier for all groups. The knowledge of these preferences will enlarge support for this innovation, and aid in the drafting of implementable guidelines and information brochures for patients, parents and professionals. © 2015 John Wiley & Sons Ltd.

Patients' preferences in transplantation from marginal donors: results of a discrete choice experiment.

PubMed

Kamran, Sara; Conti, Filomena; Pomey, Marie-Pascale; Baron, Gabriel; Calmus, Yvon; Vidal-Trecan, Gwenaëlle

2017-06-01

To increase the donor pool, the strategy of transplantation from "marginal" donors was developed though patients' preferences about these donors were insufficiently known. The preferences of patients registered on the waiting list or already transplanted in eight transplant teams covering four main organs (i.e., kidney, liver, heart, and lung) were evaluated using the discrete choice experiment method. In each left during 2 days, patients were interviewed on four scenarios. Of 178 eligible patients, 167 were interviewed; 40% accepted marginal graft in their own situation and 89% at least in one of the scenarios. Imagining urgent situations or rare profiles with difficult access to transplantation, respectively, 86% and 71% accepted these grafts. Most (76%) preferred to be informed about these grafts and 43% preferred to be involved in decision. The emergency [OR = 1.24; 95% CI: (1.06-1.45)] and the hazardousness [OR = 0.88; 95% CI: (0.78-0.99)] of the transplantation were factors independently associated with marginal graft acceptance. Most patients preferred to be informed and to be involved in the decision. Marginal grafts could be more accepted by patients in critical medical situations or perceiving their situation as critical. Physicians' practices in transplantation should be reconsidered taking into account individual preferences. This study was performed in a single country and thus reflects the cultural bias and practice thereof. © 2017 Steunstichting ESOT.

Public preferences for vaccination programmes during pandemics caused by pathogens transmitted through respiratory droplets - a discrete choice experiment in four European countries, 2013.

PubMed

Determann, Domino; Korfage, Ida J; Fagerlin, Angela; Steyerberg, Ewout W; Bliemer, Michiel C; Voeten, Helene A; Richardus, Jan Hendrik; Lambooij, Mattijs S; de Bekker-Grob, Esther W

2016-06-02

This study aims to quantify and compare preferences of citizens from different European countries for vaccination programme characteristics during pandemics, caused by pathogens which are transmitted through respiratory droplets. Internet panel members, nationally representative based on age, sex, educational level and region, of four European Union Member States (Netherlands, Poland, Spain, and Sweden, n = 2,068) completed an online discrete choice experiment. These countries, from different geographical areas of Europe, were chosen because of the availability of high-quality Internet panels and because of the cooperation between members of the project entitled Effective Communication in Outbreak Management: development of an evidence-based tool for Europe (ECOM). Data were analysed using panel latent class regression models. In the case of a severe pandemic scenario, vaccine effectiveness was the most important characteristic determining vaccination preference in all countries, followed by the body that advises on vaccination. In Sweden, the advice of family and/or friends and the advice of physicians strongly affected vaccine preferences, in contrast to Poland and Spain, where the advice of (international) health authorities was more decisive. Irrespective of pandemic scenario or vaccination programme characteristics, the predicted vaccination uptakes were lowest in Sweden, and highest in Poland. To increase vaccination uptake during future pandemics, the responsible authorities should align with other important stakeholders in the country and communicate in a coordinated manner.

Attitudes toward infection prophylaxis in pediatric oncology: a qualitative approach.

PubMed

Diorio, Caroline; Tomlinson, Deborah; Boydell, Katherine M; Regier, Dean A; Ethier, Marie-Chantal; Alli, Amanda; Alexander, Sarah; Gassas, Adam; Taylor, Jonathan; Kellow, Charis; Mills, Denise; Sung, Lillian

2012-01-01

The risks and benefits of infection prophylaxis are uncertain in children with cancer and thus, preferences should be considered in decision making. The purpose of this report was to describe the attitudes of parents, children and healthcare professionals to infection prophylaxis in pediatric oncology. THE STUDY WAS COMPLETED IN THREE PHASES: 1) An initial qualitative pilot to identify the main attributes influencing the decision to use infection prophylaxis, which were then incorporated into a discrete choice experiment; 2) A think aloud during the discrete choice experiment in which preferences for infection prophylaxis were elicited quantitatively; and 3) In-depth follow up interviews. Interviews were recorded verbatim and analyzed using an iterative, thematic analysis. Final themes were selected using a consensus approach. A total of 35 parents, 22 children and 28 healthcare professionals participated. All three groups suggested that the most important factor influencing their decision making was the effect of prophylaxis on reducing the chance of death. Themes of importance to the three groups included antimicrobial resistance, side effects of medications, the financial impact of outpatient prophylaxis and the route and schedule of administration. Effect of prophylaxis on risk of death was a key factor in decision making. Other identified factors were antimicrobial resistance, side effects of medication, financial impact and administration details. Better understanding of factors driving decision making for infection prophylaxis will help facilitate future implementation of prophylactic regiments.

Convergent validity between a discrete choice experiment and a direct, open-ended method: comparison of preferred attribute levels and willingness to pay estimates.

PubMed

Marjon van der Pol; Shiell, Alan; Au, Flora; Johnston, David; Tough, Suzanne

2008-12-01

The Discrete Choice Experiment (DCE) has become increasingly popular as a method for eliciting patient or population preferences. If DCE estimates are to inform health policy, it is crucial that the answers they provide are valid. Convergent validity is tested in this paper by comparing the results of a DCE exercise with the answers obtained from direct, open-ended questions. The two methods are compared in terms of preferred attribute levels and willingness to pay (WTP) values. Face-to-face interviews were held with 292 women in Calgary, Canada. Similar values were found between the two methods with respect to preferred levels for two out of three of the attributes examined. The DCE predicted less well for levels outside the range than for levels inside the range reaffirming the importance of extensive piloting to ensure appropriate level range in DCEs. The mean WTP derived from the open-ended question was substantially lower than the mean derived from the DCE. However, the two sets of willingness to pay estimates were consistent with each other in that individuals who were willing to pay more in the open-ended question were also willing to pay more in the DCE. The difference in mean WTP values between the two approaches (direct versus DCE) demonstrates the importance of continuing research into the different biases present across elicitation methods.

Discrete-Slots Models of Visual Working-Memory Response Times

PubMed Central

Donkin, Christopher; Nosofsky, Robert M.; Gold, Jason M.; Shiffrin, Richard M.

2014-01-01

Much recent research has aimed to establish whether visual working memory (WM) is better characterized by a limited number of discrete all-or-none slots or by a continuous sharing of memory resources. To date, however, researchers have not considered the response-time (RT) predictions of discrete-slots versus shared-resources models. To complement the past research in this field, we formalize a family of mixed-state, discrete-slots models for explaining choice and RTs in tasks of visual WM change detection. In the tasks under investigation, a small set of visual items is presented, followed by a test item in 1 of the studied positions for which a change judgment must be made. According to the models, if the studied item in that position is retained in 1 of the discrete slots, then a memory-based evidence-accumulation process determines the choice and the RT; if the studied item in that position is missing, then a guessing-based accumulation process operates. Observed RT distributions are therefore theorized to arise as probabilistic mixtures of the memory-based and guessing distributions. We formalize an analogous set of continuous shared-resources models. The model classes are tested on individual subjects with both qualitative contrasts and quantitative fits to RT-distribution data. The discrete-slots models provide much better qualitative and quantitative accounts of the RT and choice data than do the shared-resources models, although there is some evidence for “slots plus resources” when memory set size is very small. PMID:24015956

Statistical Methods for the Analysis of Discrete Choice Experiments: A Report of the ISPOR Conjoint Analysis Good Research Practices Task Force.

PubMed

Hauber, A Brett; González, Juan Marcos; Groothuis-Oudshoorn, Catharina G M; Prior, Thomas; Marshall, Deborah A; Cunningham, Charles; IJzerman, Maarten J; Bridges, John F P

2016-06-01

Conjoint analysis is a stated-preference survey method that can be used to elicit responses that reveal preferences, priorities, and the relative importance of individual features associated with health care interventions or services. Conjoint analysis methods, particularly discrete choice experiments (DCEs), have been increasingly used to quantify preferences of patients, caregivers, physicians, and other stakeholders. Recent consensus-based guidance on good research practices, including two recent task force reports from the International Society for Pharmacoeconomics and Outcomes Research, has aided in improving the quality of conjoint analyses and DCEs in outcomes research. Nevertheless, uncertainty regarding good research practices for the statistical analysis of data from DCEs persists. There are multiple methods for analyzing DCE data. Understanding the characteristics and appropriate use of different analysis methods is critical to conducting a well-designed DCE study. This report will assist researchers in evaluating and selecting among alternative approaches to conducting statistical analysis of DCE data. We first present a simplistic DCE example and a simple method for using the resulting data. We then present a pedagogical example of a DCE and one of the most common approaches to analyzing data from such a question format-conditional logit. We then describe some common alternative methods for analyzing these data and the strengths and weaknesses of each alternative. We present the ESTIMATE checklist, which includes a list of questions to consider when justifying the choice of analysis method, describing the analysis, and interpreting the results. Copyright © 2016 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Valuing Attributes of Home Palliative Care With Service Users: A Pilot Discrete Choice Experiment.

PubMed

Gomes, Barbara; de Brito, Maja; Sarmento, Vera P; Yi, Deokhee; Soares, Duarte; Fernandes, Jacinta; Fonseca, Bruno; Gonçalves, Edna; Ferreira, Pedro L; Higginson, Irene J

2017-12-01

Discrete choice experiment (DCE) is a quantitative method that helps determine which service attributes are most valued by people and consequently improve their well-being. The objective of this study was to test a new DCE on home palliative care (HPC). Cross-sectional survey using the DCE method with adult patients and their family caregivers, users of three HPC services in Portugal. Service attributes were based on a Cochrane review, a meta-ethnography, and the few existing DCEs on HPC: 1) team's availability, 2) support for family caregivers, 3) homecare support, 4) information and planning, and 5) waiting time. The experimental design consisted in three blocks of eight choice sets where participants chose between two service alternatives that combined different levels of each attribute. We piloted the DCE using cognitive interviewing. Interviews were analyzed for difficulties using Tourangeau's model of information processing. The DCE was conducted with 21 participants of 37 eligible (10 patients with median Palliative Performance Scale score = 45, 11 caregivers). Most participants found the DCE easy (median 2 from 1 to 5), although two patients did not finish the exercise. Key difficulties related to comprehension (e.g., waiting time sometimes understood as response time for visit instead of time from referral to care start) and judgment (e.g., indecision due to similar service alternatives). The DCE method is feasible and acceptable but not all patients are able to participate. In the main study phase, we will give more attention to the explanation of the waiting time attribute. Copyright © 2017 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.

Patient Preferences for Managing Insomnia: A Discrete Choice Experiment.

PubMed

Cheung, Janet M Y; Bartlett, Delwyn J; Armour, Carol L; Saini, Bandana; Laba, Tracey-Lea

2018-03-03

Despite the rapid development of effective treatments, both pharmacological and non-pharmacological, insomnia management remains suboptimal at the practice interface. Patient preferences play a critical role in influencing treatment outcomes. However, there is currently a mismatch between patient preferences and clinician recommendations, partly perpetuated by a limited understanding of the patients' decision-making process. The aim of our study was to empirically quantify patient preferences for treatment attributes common to both pharmacological and non-pharmacological insomnia treatments. An efficient dual-response discrete choice experiment was conducted to evaluate patient treatment preferences for managing insomnia. The sample included 205 patients with self-reported insomnia and an Insomnia Severity Index ≥ 14. Participants were presented with two unlabelled hypothetical scenarios with an opt-out option across 12 choice sets. Data were analyzed using a mixed multinomial logit model to investigate the influence of five attributes (i.e. time, onset of action, maintainability of improved sleep, length of treatment, and monthly cost) on treatment preferences. Treatments were preferentially viewed if they conferred long-term sleep benefits (p < 0.05); had an ongoing, as opposed to a predefined, duration of treatment course (p < 0.05); required some, as opposed to no, additional time commitment (p < 0.05); and had lower monthly out-of-pocket treatment costs (p < 0.001). However, treatment onset of action had no influence on preference. Age, help-seeking status, concession card status and fatigue severity significantly influenced treatment preference. Participants' prioritization of investing time in treatment and valuing the maintainability of therapeutic gains suggests a stronger inclination towards non-pharmacological treatment, defying current assumptions that patients prefer 'quick-fixes' for managing insomnia.

A Systematic Review Comparing the Acceptability, Validity and Concordance of Discrete Choice Experiments and Best-Worst Scaling for Eliciting Preferences in Healthcare.

PubMed

Whitty, Jennifer A; Oliveira Gonçalves, Ana Sofia

2018-06-01

The aim of this study was to compare the acceptability, validity and concordance of discrete choice experiment (DCE) and best-worst scaling (BWS) stated preference approaches in health. A systematic search of EMBASE, Medline, AMED, PubMed, CINAHL, Cochrane Library and EconLit databases was undertaken in October to December 2016 without date restriction. Studies were included if they were published in English, presented empirical data related to the administration or findings of traditional format DCE and object-, profile- or multiprofile-case BWS, and were related to health. Study quality was assessed using the PREFS checklist. Fourteen articles describing 12 studies were included, comparing DCE with profile-case BWS (9 studies), DCE and multiprofile-case BWS (1 study), and profile- and multiprofile-case BWS (2 studies). Although limited and inconsistent, the balance of evidence suggests that preferences derived from DCE and profile-case BWS may not be concordant, regardless of the decision context. Preferences estimated from DCE and multiprofile-case BWS may be concordant (single study). Profile- and multiprofile-case BWS appear more statistically efficient than DCE, but no evidence is available to suggest they have a greater response efficiency. Little evidence suggests superior validity for one format over another. Participant acceptability may favour DCE, which had a lower self-reported task difficulty and was preferred over profile-case BWS in a priority setting but not necessarily in other decision contexts. DCE and profile-case BWS may be of equal validity but give different preference estimates regardless of the health context; thus, they may be measuring different constructs. Therefore, choice between methods is likely to be based on normative considerations related to coherence with theoretical frameworks and on pragmatic considerations related to ease of data collection.

Evaluating Health Workers' Potential Resistance to New Interventions: A Role for Discrete Choice Experiments

PubMed Central

Lagarde, Mylene; Smith Paintain, Lucy; Antwi, Gifti; Jones, Caroline; Greenwood, Brian; Chandramohan, Daniel; Tagbor, Harry; Webster, Jayne

2011-01-01

Background The currently recommended approach for preventing malaria in pregnancy (MiP), intermittent preventive treatment with sulphadoxine-pyrimethamine (SP-IPT), has been questioned due to the spread of resistance to SP. Whilst trials are underway to test the efficacy of future alternative approaches, it is important to start exploring the feasibility of their implementation. Methods and Findings This study uses a discrete choice experiment (DCE) method to assess the potential resistance of health workers to changing strategies for control of MiP. In Ashanti region in Ghana, 133 antenatal clinic health workers were presented with 16 choice sets of two alternative policy options, each consisting of a bundle of six attributes representing certain clinical guidelines for controlling MiP (type of approach and drug used), possible associated maternal and neo-natal outcomes, workload and financial incentives. The data were analysed using a random effects logit model. Overall, staff showed a preference for a curative approach with pregnant women tested for malaria parasites and treated only if positive, compared to a preventive approach (OR 1.6; p = 0.001). Increasing the incidence of low birth weight or severe anaemia by 1% would reduce the odds of preferring an approach by 18% and 10% respectively. Midwives were more resistant to potential changes to current guidelines than lower-level cadres. Conclusions In Ashanti Region, resistance to change by antenatal clinic workers from a policy of SP-IPT to IST would generally be low, and it would disappear amongst midwives if health outcomes for the mother and baby were improved by the new strategy. DCEs are a promising approach to identifying factors that will increase the likelihood of effective implementation of new interventions immediately after their efficacy has been proven. PMID:21886800

Older People's Preferences for Side Effects Associated with Antimuscarinic Treatments of Overactive Bladder: A Discrete-Choice Experiment.

PubMed

Decalf, Veerle H; Huion, Anja M J; Benoit, Dries F; Denys, Marie-Astrid; Petrovic, Mirko; Everaert, Karel C M M

2017-08-01

Understanding the importance older people attribute to the different side effects associated with oral antimuscarinic treatments for overactive bladder (OAB) could help inform prescribers, healthcare policy makers and the drug industry. Our objective was to quantify the importance of the most prevalent cognitive and side effects of oral antimuscarinic treatments for OAB in older people. We conducted a discrete-choice experiment (DCE) with the assistance of an interviewer with community-dwelling and hospitalized older people aged >65 years. The DCE involved two hypothetical drugs for imaginary OAB, with three levels of four side effects for each drug, and the International Consultation on Incontinence Questionnaire-Overactive Bladder and EuroQol 5-Dimensions (EQ-5D) questionnaire were also administered. Data were analysed using a conditional logit model. In total, 276 older people participated in the study. The median age was 75 years (interquartile range [IQR] 69-80), 63% were women and 21% had OAB syndrome. The most unwanted side effect in the choice of antimuscarinics for OAB was severe cognitive effects, followed by severe constipation, severe blurred vision, severe dry mouth, moderate cognitive effects and moderate constipation. Severe cognitive effects were at least 1.7 times as important as severe constipation. Exploratory subgroup analysis showed that none of the attributes was found to be significant in people who scored as anxious or depressed on the EQ-5D, and preferences about cognitive effects, constipation and blurred vision were equal in people with and without OAB. Older people attribute more importance to loss of cognitive function as a possible side effect of antimuscarinic treatment than to the three most prevalent possible side effects of this treatment.

Patient versus neurologist preferences: A discrete choice experiment for antiepileptic drug therapies.

PubMed

Ettinger, Alan B; Carter, John A; Rajagopalan, Krithika

2018-03-01

This assessment was conducted to quantify and compare patient and neurologist preferences regarding antiepileptic drug (AED) attributes for treating epilepsy. Patients with epilepsy (≥18years, treated with AEDs) and neurologists were recruited from nationally representative US panels to complete an online survey that included a discrete choice experiment (DCE). Participants chose between two hypothetical AEDs, characterized by six attributes in the DCE, which included 1) level of seizure control/reduction; 2) dosing frequency, 3) diminished coordination and balance, 4) psychiatric issues, 5) diminished energy level, and 6) dietary restrictions. The Sawtooth Software Choice-Based Conjoint (CBC) System for CBC Analysis was used to estimate treatment attribute ranking and weighting. Of the 720 respondents (518 patients and 202 neurologists), both patients and neurologists ranked seizure control as the most important attribute (rank 1) and dietary restrictions as the least important attribute (rank 6). However, seizure control had a significantly greater weighting in neurologists' decision-making than among patients (45% vs 32%, p<0.005). On the other hand, patients considered the risks of psychiatric adverse effects (19% vs 15%), diminished coordination and balance (16% vs 10%), and fatigue or diminished energy (13% vs 11%) as significantly more important (p<0.05) than did neurologists. Patients and neurologists had similar preference ranking order, with seizure reduction being ranked the most important attribute. However, neurologist treatment preferences were significantly more influenced by seizure reduction while patient preferences were significantly more influenced by adverse effects that may impact their quality of life. Understanding how patient and neurologist perspectives differ should encourage dialog to communicate the potential risks and benefits of AED therapy and assist in the shared decision-making process. Copyright © 2018 Elsevier Inc. All rights reserved.

A discrete choice experiment to obtain a tariff for valuing informal care situations measured with the CarerQol instrument.

PubMed

Hoefman, Renske J; van Exel, Job; Rose, John M; van de Wetering, E J; Brouwer, Werner B F

2014-01-01

Economic evaluations adopting a societal perspective need to include informal care whenever relevant. However, in practice, informal care is often neglected, because there are few validated instruments to measure and value informal care for inclusion in economic evaluations. The CarerQol, which is such an instrument, measures the impact of informal care on 7 important burden dimensions (CarerQol-7D) and values this in terms of general quality of life (CarerQol-VAS). The objective of the study was to calculate utility scores based on relative utility weights for the CarerQol-7D. These tariffs will facilitate inclusion of informal care in economic evaluations. The CarerQol-7D tariff was derived with a discrete choice experiment conducted as an Internet survey among the general adult population in the Netherlands (N = 992). The choice set contained 2 unlabeled alternatives described in terms of the 7 CarerQol-7D dimensions (level range: "no,"some," and "a lot"). An efficient experimental design with priors obtained from a pilot study (N = 104) was used. Data were analyzed with a panel mixed multinomial parameter model including main and interaction effects of the attributes. The utility attached to informal care situations was significantly higher when this situation was more attractive in terms of fewer problems and more fulfillment or support. The interaction term between the CarerQol-7D dimensions physical health and mental health problems also significantly explained this utility. The tariff was constructed by adding up the relative utility weights per category of all CarerQol-7D dimensions and the interaction term. We obtained a tariff providing standard utility scores for caring situations described with the CarerQol-7D. This facilitates the inclusion of informal care in economic evaluations.

Rural practice preferences among medical students in Ghana: a discrete choice experiment

PubMed Central

Johnson, Jennifer C; Gyakobo, Mawuli; Agyei-Baffour, Peter; Asabir, Kwesi; Kotha, S Rani; Kwansah, Janet; Nakua, Emmanuel; Snow, Rachel C; Dzodzomenyo, Mawuli

2010-01-01

Abstract Objective To determine how specific job attributes influenced fourth year medical students’ stated preference for hypothetical rural job postings in Ghana. Methods Based on discussions with medical student focus groups and physicians in practice and in the Ministry of Health, we created a discrete choice experiment (DCE) that assessed how students’ stated preference for certain rural postings was influenced by various job attributes: a higher salary, free superior housing, an educational allowance for children, improved equipment, supportive management, shorter contracts before study leave and a car. We conducted the DCE among all fourth year medical students in Ghana using a brief structured questionnaire and used mixed logit models to estimate the utility of each job attribute. Findings Complete data for DCE analysis were available for 302 of 310 (97%) students. All attribute parameter estimates differed significantly from zero and had the expected signs. In the main effects mixed logit model, improved equipment and supportive management were most strongly associated with job preference (β = 1.42; 95% confidence interval, CI: 1.17 to 1.66, and β = 1.17; 95% CI: 0.96 to 1.39, respectively), although shorter contracts and salary bonuses were also associated. Discontinuing the provision of basic housing had a large negative influence (β = −1.59; 95% CI: −1.88 to −1.31). In models including gender interaction terms, women’s preferences were more influenced by supportive management and men’s preferences by superior housing. Conclusion Better working conditions were strongly associated with the stated choice of hypothetical rural postings among fourth year Ghanaian medical students. Studies are needed to find out whether job attributes determine the actual uptake of rural jobs by graduating physicians. PMID:20458371

Economic considerations and patients' preferences affect treatment selection for patients with rheumatoid arthritis: a discrete choice experiment among European rheumatologists.

PubMed

Hifinger, M; Hiligsmann, M; Ramiro, S; Watson, V; Severens, J L; Fautrel, B; Uhlig, T; van Vollenhoven, R; Jacques, P; Detert, J; Canas da Silva, J; Scirè, C A; Berghea, F; Carmona, L; Péntek, M; Keat, A; Boonen, A

2017-01-01

To compare the value that rheumatologists across Europe attach to patients' preferences and economic aspects when choosing treatments for patients with rheumatoid arthritis. In a discrete choice experiment, European rheumatologists chose between two hypothetical drug treatments for a patient with moderate disease activity. Treatments differed in five attributes: efficacy (improvement and achieved state on disease activity), safety (probability of serious adverse events), patient's preference (level of agreement), medication costs and cost-effectiveness (incremental cost-effectiveness ratio (ICER)). A Bayesian efficient design defined 14 choice sets, and a random parameter logit model was used to estimate relative preferences for rheumatologists across countries. Cluster analyses and latent class models were applied to understand preference patterns across countries and among individual rheumatologists. Responses of 559 rheumatologists from 12 European countries were included in the analysis (49% females, mean age 48 years). In all countries, efficacy dominated treatment decisions followed by economic considerations and patients' preferences. Across countries, rheumatologists avoided selecting a treatment that patients disliked. Latent class models revealed four respondent profiles: one traded off all attributes except safety, and the remaining three classes disregarded ICER. Among individual rheumatologists, 57% disregarded ICER and these were more likely from Italy, Romania, Portugal or France, whereas 43% disregarded uncommon/rare side effects and were more likely from Belgium, Germany, Hungary, the Netherlands, Norway, Spain, Sweden or UK. Overall, European rheumatologists are willing to trade between treatment efficacy, patients' treatment preferences and economic considerations. However, the degree of trade-off differs between countries and among individuals. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

The use of specialty training to retain doctors in Malawi: A discrete choice experiment.

PubMed

Mandeville, Kate L; Ulaya, Godwin; Lagarde, Mylène; Muula, Adamson S; Dzowela, Titha; Hanson, Kara

2016-11-01

Emigration has contributed to a shortage of doctors in many sub-Saharan African countries. Specialty training is highly valued by doctors and a potential tool for retention. Yet not all types of training may be valued equally. In the first study to examine preferences for postgraduate training in depth, we carried out a discrete choice experiment as part of a cross-sectional survey of all Malawian doctors within seven years of graduation and not yet in specialty training. Over August 2012 to March 2013, 148 doctors took part out of 153 eligible in Malawi. Despite evidence that specialty training is highly sought after, Malawian junior doctors would not accept all types of training. Doctors preferred timely training outside of Malawi in core specialties (internal medicine, general surgery, paediatrics, obstetrics & gynaecology). Specialty preferences are particularly strong, with most junior doctors requiring nearly double their monthly salary to accept training all in Malawi and over six-fold to accept training in ophthalmology (representing a bundle of unpopular but priority specialties). In contrast, the location of work before training did not significantly influence most doctors' choices when guaranteed specialty training. Using a latent class model, we identified four subgroups of junior doctors with distinct preferences. Policy simulations showed that these preferences could be leveraged by policymakers to improve retention in exchange for guaranteed specialty training, however incentivising the uptake of training in priority specialties will only be effective in those with more flexible preferences. These results indicate that indiscriminate expansion of postgraduate training to slow emigration of doctors from sub-Saharan African countries may not be effective unless doctors' preferences are taken into account. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Financial incentives to discontinue long-term benzodiazepine use: a discrete choice experiment investigating patient preferences and willingness to participate.

PubMed

Marti, Joachim; Bachhuber, Marcus; Feingold, Jordyn; Meads, David; Richards, Michael; Hennessy, Sean

2017-10-06

Investigate the acceptability of financial incentives for initiating a medically supervised benzodiazepine discontinuation programme among people with long-term benzodiazepine use and to identify programme features that influence willingness to participate. We conducted a discrete choice experiment in which we presented a variety of incentive-based programs to a sample of older adults with long-term benzodiazepine use identified using the outpatient electronic health record of a university-owned health system. We studied four programme variables: incentive amount for initiating the programme, incentive amount for successful benzodiazepine discontinuation, lottery versus certain payment and whether partial payment was given for dose reduction. Respondents reported their willingness to participate in the programmes and additional information was collected on demographics, history of use and anxiety symptoms. The overall response rate was 28.4%. Among the 126 respondents, all four programme variables influenced stated preferences. Respondents strongly preferred guaranteed cash-based incentives as opposed to a lottery, and the dollar amount of both the starting and conditional incentives had a substantial impact on choice. Willingness to participate increased with the amount of conditional incentive. Programme participation also varied by gender, duration of use and income. Participation in an incentive-based benzodiazepine discontinuation programme might be relatively low, but is modifiable by programme variables including incentive amounts. These results will be helpful to inform the design of future trials of benzodiazepine discontinuation programmes. Further research is needed to assess the financial viability and potential cost-effectiveness of such economic incentives. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Understanding rational non-adherence to medications. A discrete choice experiment in a community sample in Australia

PubMed Central

2012-01-01

Background In spite of the potential impact upon population health and expenditure, interventions promoting medication adherence have been found to be of moderate effectiveness and cost effectiveness. Understanding the relative influence of factors affecting patient medication adherence decisions and the characteristics of individuals associated with variation in adherence will lead to a better understanding of how future interventions should be designed and targeted. This study aims to explore medication-taking decisions that may underpin intentional medication non-adherence behaviour amongst a community sample and the relative importance of medication specific factors and patient background characteristics contributing to those decisions. Methods A discrete choice experiment conducted through a web-enabled online survey was used to estimate the relative importance of eight medication factors (immediate and long-term medication harms and benefits, cost, regimen, symptom severity, alcohol restrictions) on the preference to continue taking a medication. To reflect more closely what usually occurs in practice, non-disease specific medication and health terms were used to mimic decisions across multiple medications and conditions.161 general community participants, matching the national Australian census data (age, gender) were recruited through an online panel provider (participation rate: 10%) in 2010. Results Six of the eight factors (i.e. immediate and long-term medication harms and benefits, cost, and regimen) had a significant influence on medication choice. Patient background characteristics did not improve the model. Respondents with private health insurance appeared less sensitive to cost then those without private health insurance. In general, health outcomes, framed as a side-effect, were found to have a greater influence over adherence than outcomes framed as therapeutic benefits. Conclusions Medication-taking decisions are the subject of rational choices, influenced by the attributes of treatments and potentially amenable to intervention through education, strategic pricing and the altering of dosing characteristics. Understanding individual treatment preferences is thus an important step to improving adherence support provision in practice. Re-framing future interventions and policies to support rational and informed individual patient choices, is the way forward to realising the full potential health and economic benefits from the efficacious use of medications. PMID:22715853

Understanding rational non-adherence to medications. A discrete choice experiment in a community sample in Australia.

PubMed

Laba, Tracey-Lea; Brien, Jo-Anne; Jan, Stephen

2012-06-20

In spite of the potential impact upon population health and expenditure, interventions promoting medication adherence have been found to be of moderate effectiveness and cost effectiveness. Understanding the relative influence of factors affecting patient medication adherence decisions and the characteristics of individuals associated with variation in adherence will lead to a better understanding of how future interventions should be designed and targeted. This study aims to explore medication-taking decisions that may underpin intentional medication non-adherence behaviour amongst a community sample and the relative importance of medication specific factors and patient background characteristics contributing to those decisions. A discrete choice experiment conducted through a web-enabled online survey was used to estimate the relative importance of eight medication factors (immediate and long-term medication harms and benefits, cost, regimen, symptom severity, alcohol restrictions) on the preference to continue taking a medication. To reflect more closely what usually occurs in practice, non-disease specific medication and health terms were used to mimic decisions across multiple medications and conditions.161 general community participants, matching the national Australian census data (age, gender) were recruited through an online panel provider (participation rate: 10%) in 2010. Six of the eight factors (i.e. immediate and long-term medication harms and benefits, cost, and regimen) had a significant influence on medication choice. Patient background characteristics did not improve the model. Respondents with private health insurance appeared less sensitive to cost then those without private health insurance. In general, health outcomes, framed as a side-effect, were found to have a greater influence over adherence than outcomes framed as therapeutic benefits. Medication-taking decisions are the subject of rational choices, influenced by the attributes of treatments and potentially amenable to intervention through education, strategic pricing and the altering of dosing characteristics. Understanding individual treatment preferences is thus an important step to improving adherence support provision in practice. Re-framing future interventions and policies to support rational and informed individual patient choices, is the way forward to realising the full potential health and economic benefits from the efficacious use of medications.

Taiwanese consumer survey data for investigating the role of information on equivalence of organic standards in directing food choice.

PubMed

Yeh, Ching-Hua; Hartmann, Monika; Hirsch, Stefan

2018-06-01

The presentation of credence attributes such as the product's origin or the production method has a significant influence on consumers' food purchase decisions. The dataset includes survey responses from a discrete choice experiment with 1309 food shoppers in Taiwan using the example of sweet pepper. The survey was carried out in 2014 in the three largest Taiwanese cities. It evaluates the impact of providing information on the equality of organic standards on consumers' preferences at the example of sweet pepper. Equality of organic standards implies that regardless of products' country-of-origin (COO) organic certifications are based on the same production regulation and managerial processes. Respondents were randomly allocated to the information treatment and the control group. The dataset contains the product choices of participants in both groups, as well as their sociodemographic information.

Prioritising patients for bariatric surgery: building public preferences from a discrete choice experiment into public policy

PubMed Central

Whitty, Jennifer A; Ratcliffe, Julie; Kendall, Elizabeth; Burton, Paul; Wilson, Andrew; Littlejohns, Peter; Harris, Paul; Krinks, Rachael; Scuffham, Paul A

2015-01-01

Objectives To derive priority weights for access to bariatric surgery for obese adults, from the perspective of the public. Setting Australian public hospital system. Participants Adults (N=1994), reflecting the age and gender distribution of Queensland and South Australia. Primary and secondary outcome measures A discrete choice experiment in which respondents indicated which of two individuals with different characteristics should be prioritised for surgery in repeated hypothetical choices. Potential surgery recipients were described by seven key characteristics or attributes: body mass index (BMI), presence of comorbid conditions, age, family history, commitment to lifestyle change, time on the surgical wait list and chance of maintaining weight loss following surgery. A multinomial logit model was used to evaluate preferences and derive priority weights (primary analysis), with a latent class model used to explore respondent characteristics that were associated with variation in preference across the sample (see online supplementary analysis). Results A preference was observed to prioritise individuals who demonstrated a strong commitment to maintaining a healthy lifestyle as well as individuals categorised with very severe (BMI≥50 kg/m2) or (to a lesser extent) severe (BMI≥40 kg/m2) obesity, those who already have obesity-related comorbidity, with a family history of obesity, with a greater chance of maintaining weight loss or who had spent a longer time on the wait list. Lifestyle commitment was considered to be more than twice as important as any other criterion. There was little tendency to prioritise according to the age of the recipient. Respondent preferences were dependent on their BMI, previous experience with weight management surgery, current health state and education level. Conclusions This study extends our understanding of the publics’ preferences for priority setting to the context of bariatric surgery, and derives priority weights that could be used to assist bodies responsible for commissioning bariatric services. PMID:26474940

How important is local food to organic-minded consumers?

PubMed

Hempel, Corinna; Hamm, Ulrich

2016-01-01

The study deals with German consumers' attitudes towards organic food and local food, their food purchase behaviour and their personal characteristics. The purpose is to investigate the differences in attitudes and willingness-to-pay values between consumers who consider the organic production of food (very) important and those who consider it less important. This study combines a consumer survey with an in-store, discrete choice experiment. In the analysis, findings from the consumer survey were related to the choices made by consumers in the experiment. Consumers' preferences and willingness-to-pay values were estimated through random parameter logit modelling. Organic-minded consumers (i.e. those who regarded organic food production as (very) important in the survey) have stronger preferences and estimated willingness-to-pay values for organic as well as local products. Locally produced food, as opposed to food from neighbouring countries or non-EU countries, is preferred over organically produced food by both consumer groups which demonstrates that organic-minded consumers do not only consider organic food production as important, but also value local food production in a purchase situation. Hence, it can be assumed that local food production complements organic food production for the group of organic-minded consumers. This contribution is the first study dealing with local and organic food purchase behaviour in Germany that examines four different products and is carried out in rural as well as urban locations in four different regions. Due to the application of a choice experiment including no-choice options and binding purchase decisions, the results are expected to be closer to real purchase situations than results of direct questioning and choice experiments in online applications. Copyright © 2015 Elsevier Ltd. All rights reserved.

Incorporating social impact on new product adoption in choice modeing: A case study in green vehicles

DOE Office of Scientific and Technical Information (OSTI.GOV)

He, Lin; Wang, Mingxian; Chen, Wei

While discrete choice analysis is prevalent in capturing consumer preferences and describing their choice behaviors in product design, the traditional choice modeling approach assumes that each individual makes independent decisions, without considering the social impact. However, empirical studies show that choice is social - influenced by many factors beyond engineering performance of a product and consumer attributes. To alleviate this limitation, we propose a new choice modeling framework to capture the dynamic influence from social networks on consumer adoption of new products. By introducing social influence attributes into a choice utility function, social network simulation is integrated with the traditionalmore » discrete choice analysis in a three-stage process. Our study shows the need for considering social impact in forecasting new product adoption. Using hybrid electric vehicles as an example, our work illustrates the procedure of social network construction, social influence evaluation, and choice model estimation based on data from the National Household Travel Survey. Our study also demonstrates several interesting findings on the dynamic nature of new technology adoption and how social networks may influence hybrid electric vehicle adoption. (C) 2014 Elsevier Ltd. All rights reserved« less

A Minimum-Residual Finite Element Method for the Convection-Diffusion Equation

DTIC Science & Technology

2013-05-01

4p . We note that these two choices of discretization for V are not mutually exclusive, and that novel choices for Vh are likely the key to yielding...the inside with the positive- definite operator A, which is precisely the discrete system that arises under the optimal test function framework of DPG...converts the fine-scale problem into a symmetric-positive definite one, allowing for a well-behaved subgrid model of fine scale behavior. We begin again

ECONOMICS NOBEL: Dealing With Biases and Discrete Choices.

PubMed

Seife, C

2000-10-20

This year's Bank of Sweden Prize in Economic Sciences, given in honor of Alfred Nobel, goes to two researchers who gave the field of microeconomics--the study of individuals' economic behavior--new tools to help draw conclusions from imperfect data. James Heckman of the University of Chicago wins half of this year's prize for coming up with ways to deal with selection biases. Daniel McFadden of the University of California, Berkeley, tackled a different conundrum: how to quantify discrete choices rather than continuous ones.

The effects of valence-based and discrete emotional states on aesthetic response.

PubMed

Cheng, Yin-Hui

2013-01-01

There is increasing recognition that consumer aesthetics--the responses of consumers to the aesthetic or appearance aspects of products--has become an important area of marketing in recent years. Consumer aesthetic responses to a product are a source of pleasure for the consumer. Previous research into the aesthetic responses to products has often emphasized exterior factors and visual design, but studies have seldom considered the psychological aesthetic experience of consumers, and in particular their emotional state. This study attempts to bridge this gap by examining the link between consumers' emotions and their aesthetic response to a product. Thus, the major goal of this study was to determine how valence-based and discrete emotional states influence choice. In Studies 1 and 2, positive and negative emotions were manipulated to implement two different induction techniques and explore the effect of emotions on participants' choices in two separate experiments. The results of both experiments confirmed the predictions, indicating that aesthetic responses and purchase intention are functions of emotional valence, such that both are stronger for people in a positive emotional state than for those in a negative emotional state. Study 2 also used a neutral affective state to establish the robustness of this observed effect of incidental affect. The results of Study 3 demonstrate that aesthetic response and purchase intention are not only a function of affect valence, but also are affected by the certainty appraisal associated with specific affective states. This research, therefore, contributes to the literature by offering empirical evidence that incidental affect is a determinant of aesthetic response.

Patients' Preferences for the Treatment of Metastatic Castrate-resistant Prostate Cancer: A Discrete Choice Experiment.

PubMed

Eliasson, Lina; de Freitas, Hayley M; Dearden, Lindsay; Calimlim, Brian; Lloyd, Andrew J

2017-04-01

Patient treatment preferences are increasingly being used to inform health care decision making. This discrete choice experiment assessed how men perceive the risks and benefits of hypothetical treatment options for metastatic castrate-resistant prostate cancer (mCRPC). Treatment attributes for inclusion were identified through a review of the literature and product labels. Expert interviews confirmed clinical appropriateness and patient relevance of the attributes, which included effectiveness (delay in months before chemotherapy), steroid use, possible drug interactions (additional hospital visits for monitoring), fogginess (effects on cognition and memory), fatigue (extreme tiredness), food restrictions, and bone pain. Following a pilot, the final discrete choice experiment included 18 choice sets presenting treatments for mCRPC and was completed by men with mCRPC in France, Germany, and the United Kingdom. Data were analyzed using a conditional logit model, with odds ratios (ORs) used to indicate preference for attributes, and tradeoff measures (TOM) were estimated using the ratio of coefficients. Within each attribute category and with all other factors being equal, participants (N = 285) indicated a strong preference for treatments that fully control bone pain (OR = 12.069 [95% CI, 10.555-13.800]) and for treatments that delay chemotherapy (OR, 1.727 [95% CI, 1.548-1.927]). They also preferred treatments that were associated with the lowest risk of fogginess (OR, 2.115 [95% CI, 1.849-2.420]), a lower risk of fatigue (OR, 1.365 [95% CI 1.219-1.528]), and fewer additional hospital visits (OR, 1.245 [95% CI 1.111-1.397]) than the respective reference categories. Participants preferred to use steroids under advice from a physician (OR, 1.275 [95% CI 1.132-1.437]). Food restrictions related to taking medication were not a significant concern for participants. TOM results indicated that large tradeoffs in effectiveness, fogginess, and fatigue are required for patients to prefer a treatment with uncontrolled bone pain that is very difficult to live with. Men with mCRPC consider a wide range of factors when making decisions regarding their treatment. They showed a strong preference for treatment associated with better control of bone pain. They also placed value on treatments that could delay the need for chemotherapy, and they preferred to avoid side effects such as cognition and memory loss, and extreme tiredness. TOMs highlighted the importance of symptom control, even compared with potential side effects. An understanding of the degree to which patients value the attributes associated with various treatment options will assist clinicians and health care professionals when making decisions regarding the management of men with mCRPC. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Nonlinear Socio-Ecological Dynamics and First Principles ofCollective Choice Behavior of ``Homo Socialis"

NASA Astrophysics Data System (ADS)

Sonis, M.

Socio-ecological dynamics emerged from the field of Mathematical SocialSciences and opened up avenues for re-examination of classical problems of collective behavior in Social and Spatial sciences. The ``engine" of this collective behavior is the subjective mental evaluation of level of utilities in the future, presenting sets of composite socio-economic-temporal-locational advantages. These dynamics present new laws of collective multi-population behavior which are the meso-level counterparts of the utility optimization individual behavior. The central core of the socio-ecological choice dynamics includes the following first principle of the collective choice behavior of ``Homo Socialis" based on the existence of ``collective consciousness": the choice behavior of ``Homo Socialis" is a collective meso-level choice behavior such that the relative changes in choice frequencies depend on the distribution of innovation alternatives between adopters of innovations. The mathematical basis of the Socio-Ecological Dynamics includes two complementary analytical approaches both based on the use of computer modeling as a theoretical and simulation tool. First approach is the ``continuous approach" --- the systems of ordinary and partial differential equations reflecting the continuous time Volterra ecological formalism in a form of antagonistic and/or cooperative collective hyper-games between different sub-sets of choice alternatives. Second approach is the ``discrete approach" --- systems of difference equations presenting a new branch of the non-linear discrete dynamics --- the Discrete Relative m-population/n-innovations Socio-Spatial Dynamics (Dendrinos and Sonis, 1990). The generalization of the Volterra formalism leads further to the meso-level variational principle of collective choice behavior determining the balance between the resulting cumulative social spatio-temporal interactions among the population of adopters susceptible to the choice alternatives and the cumulative equalization of the power of elites supporting different choice alternatives. This balance governs the dynamic innovation choice process and constitutes the dynamic meso-level counterpart of the micro-economic individual utility maximization principle.

Valuing health risk in agriculture: a choice experiment approach to pesticide use in China.

PubMed

Jin, Jianjun; Wang, Wenyu; He, Rui; Gong, Haozhou

2017-07-01

This paper presents a choice experiment approach to investigate farmers' valuations for health risk changes associated with pesticide use in Anqiu County, China. An empirical comparison on the disparity between farmers' willingness to pay (WTP) for a health risk reduction and willingness to accept (WTA) for the same risk increase is also conducted. Respondents were randomly assigned into the WTP group or the WTA group. Four attributes (health consequence, baseline risk, risk change size, and price) were identified and included. The results show that cancer consequence due to pesticide use decreases the utility of the farmer. A higher baseline risk has a higher WTP to reduce the risk and a higher probability of receiving compensation. If the health risk change size is bigger, it will result in a higher WTP and higher compensation. Household income, education, and age have significant and positive impacts on farmers' WTP. Farmers who are more educated or female are more likely to accept the compensation scheme if health risks increase. The marginal WTA for the same risk change is about two times higher than the marginal WTP. The findings of this study can contribute to the literature comparing people's WTP and WTA in a discrete choice experiment on valuing health risk changes associated with pesticide use.

Do women and providers value the same features of contraceptive products? Results of a best-worst stated preference experiment.

PubMed

Weisberg, Edith; Bateson, Deborah; Knox, Stephanie; Haas, Marion; Viney, Rosalie; Street, Deborah; Fiebig, Denzil

2013-06-01

To determine how women and physicians rate individual characteristics of contraceptives. Discrete choice experiments are used in health economics to elicit preferences for healthcare products. A choice experiment uses hypothetical scenarios to determine which individual factors influence choice. Women and general practitioners (GPs) were shown individual characteristics of contraceptives, not always matching existing methods, and chose the best and worst features. Two hundred women, mean age 36, 71% using contraception, were presented with descriptions of 16 possible methods and asked to indicate their preference for individual characteristics. One hundred and sixty-two GPs, mostly women, also completed 16 descriptions. Longer duration of action was most favoured by both, followed by lighter periods with less pain or amenorrhoea. The least attractive features for women were heavier and more painful periods, high cost, irregular periods, low efficacy (10% failure) and weight gain of 3 kg. GPs ranked a 10% pregnancy rate as least attractive followed by heavy painful periods and a 5% failure rate. Women and GPs differed in their ranking of contraceptive characteristics. Long duration of use, high efficacy, minimal or no bleeding without pain, were preferred by both. Very undesirable were heavy periods especially with pain, and low efficacy.

Insurees' preferences in hospital choice-A population-based study.

PubMed

Schuldt, Johannes; Doktor, Anna; Lichters, Marcel; Vogt, Bodo; Robra, Bernt-Peter

2017-10-01

In Germany, the patient himself makes the choice for or against a health service provider. Hospital comparison websites offer him possibilities to inform himself before choosing. However, it remains unclear, how health care consumers use those websites, and there is little information about how preferences in hospital choice differ interpersonally. We conducted a Discrete-Choice-Experiment (DCE) on hospital choice with 1500 randomly selected participants (age 40-70) in three different German cities selecting four attributes for hospital vignettes. The analysis of the study draws on multilevel mixed effects logit regression analyses with the dependent variables: "chance to select a hospital" and "choice confidence". Subsequently, we performed a Latent-Class-Analysis to uncover consumer segments with distinct preferences. 590 of the questionnaires were evaluable. All four attributes of the hospital vignettes have a significant impact on hospital choice. The attribute "complication rate" exerts the highest impact on consumers' decisions and reported choice confidence. Latent-Class-Analysis results in one dominant consumer segment that considered the complication rate the most important decision criterion. Using DCE, we were able to show that the complication rate is an important trusted criterion in hospital choice to a large group of consumers. Our study supports current governmental efforts in Germany to concentrate the provision of specialized health care services. We suggest further national and cross-national research on the topic. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

An Optimal Mobile Service for Telecare Data Synchronization using a Role-based Access Control Model and Mobile Peer-to-Peer Technology.

PubMed

Ke, Chih-Kun; Lin, Zheng-Hua

2015-09-01

The progress of information and communication technologies (ICT) has promoted the development of healthcare which has enabled the exchange of resources and services between organizations. Organizations want to integrate mobile devices into their hospital information systems (HIS) due to the convenience to employees who are then able to perform specific healthcare processes from any location. The collection and merage of healthcare data from discrete mobile devices are worth exploring possible ways for further use, especially in remote districts without public data network (PDN) to connect the HIS. In this study, we propose an optimal mobile service which automatically synchronizes the telecare file resources among discrete mobile devices. The proposed service enforces some technical methods. The role-based access control model defines the telecare file resources accessing mechanism; the symmetric data encryption method protects telecare file resources transmitted over a mobile peer-to-peer network. The multi-criteria decision analysis method, ELECTRE (Elimination Et Choice Translating Reality), evaluates multiple criteria of the candidates' mobile devices to determine a ranking order. This optimizes the synchronization of telecare file resources among discrete mobile devices. A prototype system is implemented to examine the proposed mobile service. The results of the experiment show that the proposed mobile service can automatically and effectively synchronize telecare file resources among discrete mobile devices. The contribution of this experiment is to provide an optimal mobile service that enhances the security of telecare file resource synchronization and strengthens an organization's mobility.

Public preferences for prioritizing preventive and curative health care interventions: a discrete choice experiment.

PubMed

Luyten, Jeroen; Kessels, Roselinde; Goos, Peter; Beutels, Philippe

2015-03-01

Setting fair health care priorities counts among the most difficult ethical challenges our societies are facing. To elicit through a discrete choice experiment the Belgian adult population's (18-75 years; N = 750) preferences for prioritizing health care and investigate whether these preferences are different for prevention versus cure. We used a Bayesian D-efficient design with partial profiles, which enables considering a large number of attributes and interaction effects. We included the following attributes: 1) type of intervention (cure vs. prevention), 2) effectiveness, 3) risk of adverse effects, 4) severity of illness, 5) link between the illness and patient's health-related lifestyle, 6) time span between intervention and effect, and 7) patient's age group. All attributes were statistically significant contributors to the social value of a health care program, with patient's lifestyle and age being the most influential ones. Interaction effects were found, showing that prevention was preferred to cure for disease in young adults, as well as for severe and lethal disease in people of any age. However, substantial differences were found in the preferences of respondents from different age groups, with different lifestyles and different health states. Our study suggests that according to the Belgian public, contextual factors of health gains such as patient's age and health-related lifestyle should be considered in priority setting decisions. The studies, however, revealed substantial disagreement in opinion between different population subgroups. Copyright © 2015 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Preferences for home- and community-based long-term care services in Germany: a discrete choice experiment.

PubMed

Lehnert, T; Günther, O H; Hajek, A; Riedel-Heller, S G; König, H H

2018-04-06

Most people prefer to "age in place" and to remain in their homes for as long as possible even in case they require long-term care. While informal care is projected to decrease in Germany, the use of home- and community-based services (HCBS) can be expected to increase in the future. Preference-based data on aspects of HCBS is needed to optimize person-centered care. To investigate preferences for home- and community-based long-term care services packages. Discrete choice experiment conducted in mailed survey. Randomly selected sample of the general population aged 45-64 years in Germany (n = 1.209). Preferences and marginal willingness to pay (WTP) for HCBS were assessed with respect to five HCBS attributes (with 2-4 levels): care time per day, service level of the HCBS provider, quality of care, number of different caregivers per month, co-payment. Quality of care was the most important attribute to respondents and small teams of regular caregivers (1-2) were preferred over larger teams. Yet, an extended range of services of the HCBS provider was not preferred over a more narrow range. WTP per hour of HCBS was €8.98. Our findings on preferences for HCBS in the general population in Germany add to the growing international evidence of preferences for LTC. In light of the great importance of high care quality to respondents, reimbursement for services by HCBS providers could be more strongly linked to the quality of services.

Assessing user preferences for sexually transmitted infection testing services: a discrete choice experiment

PubMed Central

Llewellyn, Carrie; Pollard, Alex; Lagarde, Mylene; Richardson, Daniel; Cairns, John; Fisher, Martin; Smith, Helen

2012-01-01

Objective To assess user preferences for different aspects of sexually transmitted infection (STI) testing services. Design A discrete choice experiment. Setting 14 centres offering tests for STIs in East Sussex, England. Participants People testing for STIs. Main outcome measure (Adjusted) ORs in relation to preferred service characteristics. Results 3358 questionnaires were returned; mean age 26 (SD 9.4) years. 70% (2366) were recruited from genitourinary medicine (GUM) clinics. The analysis suggested that the most important characteristics to users were whether ‘staff had specialist STI knowledge’ compared with ‘staff without it’ (OR 2.55; 95% CI 2.47 to 2.63) and whether ‘tests for all STIs’ were offered rather than ‘some’ (OR 2.19; 95% CI 2.12 to 2.25). They remained the most important two service characteristics despite stratifying the analysis by variables such as age and sex. Staff levels of expertise were viewed as particularly important by people attending CASH centres, women and non-men who have sex with men. A ‘text or call to a mobile phone’ and ‘dropping in and waiting’ were generally the preferred methods of results reporting and appointment system, respectively. Conclusions This study suggests that people testing for STIs place particular importance on testing for all infections rather than some and staff with specialist STI knowledge. Thus, targets based purely on waiting up to 48 h for an appointment are misguided from a user perspective. PMID:22661632

Valuing QALYs in Relation to Equity Considerations Using a Discrete Choice Experiment.

PubMed

van de Wetering, Liesbet; van Exel, Job; Bobinac, Ana; Brouwer, Werner B F

2015-12-01

To judge whether an intervention offers value for money, the incremental costs per gained quality-adjusted life-year (QALY) need to be compared with some relevant threshold, which ideally reflects the monetary value of health gains. Literature suggests that this value may depend on the equity context in which health gains are produced, but the value of a QALY in relation to equity considerations has remained largely unexplored. The objective of this study was to estimate the social marginal willingness to pay (MWTP) for QALY gains in different equity subgroups, using a discrete choice experiment (DCE). Both severity of illness (operationalized as proportional shortfall) and fair innings (operationalized as age) were considered as grounds for differentiating the value of health gains. We obtained a sample of 1205 respondents, representative of the adult population of the Netherlands. The data was analysed using panel mixed multinomial logit (MMNL) and latent class models. The panel MMNL models showed counterintuitive results, with more severe health states reducing the probability of receiving treatment. The latent class models revealed distinct preference patterns in the data. MWTP per QALY was sensitive to severity of disease among a substantial proportion of the public, but not to the age of care recipients. These findings emphasize the importance of accounting for preference heterogeneity among the public on value-laden issues such as prioritizing health care, both in research and decision making. This study emphasises the need to further explore the monetary value of a QALY in relation to equity considerations.

How to attract health students to remote areas in Indonesia: a discrete choice experiment.

PubMed

Efendi, Ferry; Chen, Ching-Min; Nursalam, Nursalam; Andriyani, Nurul Wachyu Fitriyah; Kurniati, Anna; Nancarrow, Susan Alison

2016-10-01

Remote areas of Indonesia lack sufficient health workers to meet the health-care needs of the population. There is an urgent need for evidence regarding interventions to attract health workers and specifically health students to serve in remote areas. The aim of this research was to analyze the job preferences of health students to develop effective policies to improve the recruitment and retention of health students in remote areas. A discrete choice experiment was conducted to investigate health students' preferences regarding job characteristics. This study was conducted in three different regions of Indonesia, with a total included 400 health students. Mixed logit models were used to explore the stated preferences for each attribute. Data were collected from 150 medical, 150 nursing and 100 midwifery students. Medical students gave the highest preference for receiving study assistance, while nursing students viewed salary as the most important. Midwifery students valued advanced quality facilities as an important attribute. This study confirmed the importance of combination interventions in attracting and retaining health workers in remote areas of Indonesia. Money is not the only factor affecting student preferences to take up a rural post; good management and better facilities were viewed as important by all health students. Addressing health student preferences, which are the candidate of future health workforce, would help the nation solve the recruitment and retention issues. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

Differences in Waiting List Prioritization Preferences of Occupational Therapists, Elderly People, and Persons With Disabilities: A Discrete Choice Experiment.

PubMed

Raymond, Marie-Hélène; Demers, Louise; Feldman, Debbie Ehrmann

2018-01-01

To compare the preferences of occupational therapists, elderly people, and adults with disabilities regarding prioritization criteria for occupational therapy waiting lists in home care. Discrete choice experiment survey. Survey mailed to occupational therapists working in home care and community-dwelling elderly or disabled persons. A sample (N=714) of home-based occupational therapists (n=241), elderly persons from a bank of research participants (n=226), and adults with physical disabilities recruited through community organizations (n=247). Not applicable. The dependent variable was whether the referral scenario was prioritized or not in each question. The results were analyzed through logistic regression using conditional logit models. Prioritization preferences differed between groups (P<.001). Occupational therapists most strongly prioritized people who had a few falls (odds ratio vs no falls, 48.7), whereas elderly people and adults with disabilities most strongly prioritized people who were unable to enter and exit the home (odds ratio vs no difficulty entering and exiting the home, 30.8 for elderly people and 16.8 for persons with disabilities.) CONCLUSIONS: Our results highlight the gap between the priorities of home-based occupational therapists and their target clientele. Although further inquiry is needed to inform priority setting, the findings emphasize the importance of public or patient involvement in decisions on waiting list prioritization. Copyright © 2017 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Valuing the benefits of weight loss programs: an application of the discrete choice experiment.

PubMed

Roux, Larissa; Ubach, Christina; Donaldson, Cam; Ryan, Mandy

2004-08-01

Obesity is a leading health threat. Determination of optimal therapies for long-term weight loss remains a challenge. Evidence suggests that successful weight loss depends on the compliance of weight loss program participants with their weight loss efforts. Despite this, little is known regarding the attributes influencing such compliance. The purpose of this study was to assess, using a discrete choice experiment (DCE), the relative importance of weight loss program attributes to its participants and to express these preferences in terms of their willingness to pay for them. A DCE survey explored the following weight loss program attributes in a sample of 165 overweight adults enrolled in community weight loss programs: cost, travel time required to attend, extent of physician involvement (e.g., none, monthly, every 2 weeks), components (e.g., diet, exercise, behavior change) emphasized, and focus (e.g., group, individual). The rate at which participants were willing to trade among attributes and the willingness to pay for different configurations of combined attributes were estimated using regression modeling. All attributes investigated appeared to be statistically significant. The most important unit change was "program components emphasized" (e.g., moving from diet only to diet and exercise). The majority of participants were willing to pay for weight loss programs that reflected their preferences. The DCE tool was useful in quantifying and understanding individual preferences in obesity management and provided information that could help to maximize the efficiency of existing weight loss programs or the design of new programs.

Impact of Retirement Choices of Early Career Marines: A Choice Analysis Model

DTIC Science & Technology

2013-03-01

CHOICES OF EARLY CAREER MARINES: A CHOICE ANALYSIS MODEL by André G. La Taste Aaron Masaitis March 2013 Thesis Advisor: Michael Dixon... ANALYSIS MODEL 5. FUNDING NUMBERS 6. AUTHOR(S) André G. La Taste, Aaron Masaitis 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Naval Postgraduate...system. The research will be conducted using a discrete choice analysis methodology that is often used to differentiate factors that lead to

Using stated preference discrete choice modelling to evaluate the introduction of varicella vaccination.

PubMed

Hall, Jane; Kenny, Patricia; King, Madeleine; Louviere, Jordan; Viney, Rosalie; Yeoh, Angela

2002-07-01

Applications of stated preference discrete choice modelling (SPDCM) in health economics have been used to estimate consumer willingness to pay and to broaden the range of consequences considered in economic evaluation. This paper demonstrates how SPDCM can be used to predict participation rates, using the case of varicella (chickenpox) vaccination. Varicella vaccination may be cost effective compared to other public health programs, but this conclusion is sensitive to the proportion of the target population immunised. A choice experiment was conducted on a sample of Australian parents to predict uptake across a range of hypothetical programs. Immunisation rates would be increased by providing immunisation at no cost, by requiring it for school entry, by increasing immunisation rates in the community and decreasing the incidence of mild and severe side effects. There were two significant interactions; price modified the effect of both support from authorities and severe side effects. Country of birth was the only significant demographic characteristic. Depending on aspects of the immunisation program, the immunisation rates of children with Australian-born parents varied from 9% to 99% while for the children with parents born outside Australia they varied from 40% to 99%. This demonstrates how SPDCM can be used to understand the levels of attributes that will induce a change in the decision to immunise, the modification of the effect of one attribute by another, and subgroups in the population. Such insights can contribute to the optimal design and targeting of health programs. Copyright 2002 John Wiley & Sons, Ltd.

Dealing with the health state 'dead' when using discrete choice experiments to obtain values for EQ-5D-5L heath states.

PubMed

Ramos-Goñi, Juan Manuel; Rivero-Arias, Oliver; Errea, María; Stolk, Elly A; Herdman, Michael; Cabasés, Juan Manuel

2013-07-01

To evaluate two different methods to obtain a dead (0)--full health (1) scale for EQ-5D-5L valuation studies when using discrete choice (DC) modeling. The study was carried out among 400 respondents from Barcelona who were representative of the Spanish population in terms of age, sex, and level of education. The DC design included 50 pairs of health states in five blocks. Participants were forced to choose between two EQ-5D-5L states (A and B). Two extra questions concerned whether A and B were considered worse than dead. Each participant performed ten choice exercises. In addition, values were collected using lead-time trade-off (lead-time TTO), for which 100 states in ten blocks were selected. Each participant performed five lead-time TTO exercises. These consisted of DC models offering the health state 'dead' as one of the choices--for which all participants' responses were used (DCdead)--and a model that included only the responses of participants who chose at least one state as worse than dead (WTD) (DCWTD). The study also estimated DC models rescaled with lead-time TTO data and a lead-time TTO linear model. The DC(dead) and DCWTD models produced relatively similar results, although the coefficients in the DCdead model were slightly lower. The DC model rescaled with lead-time TTO data produced higher utility decrements. Lead-time TTO produced the highest utility decrements. The incorporation of the state 'dead' in the DC models produces results in concordance with DC models that do not include 'dead'.

Convergent validity between willingness to pay elicitation methods: an application to Grand Canyon whitewater boaters

USGS Publications Warehouse

Neher, Christopher; Bair, Lucas S.; Duffield, John; Patterson, David A.; Neher, Katherine

2018-01-01

We directly compare trip willingness to pay (WTP) values between dichotomous choice contingent valuation (DCCV) and discrete choice experiment (DCE) stated preference surveys of private party Grand Canyon whitewater boaters. The consistency of DCCV and DCE estimates is debated in the literature, and this study contributes to the body of work comparing the methods. Comparisons were made of mean WTP estimates for four hypothetical Colorado River flow-level scenarios. Boaters were found to most highly value mid-range flows, with very low and very high flows eliciting lower WTP estimates across both DCE and DCCV surveys. Mean WTP precision was estimated through simulation. No statistically significant differences were detected between the two methods at three of the four hypothetical flow levels.

Volition and eye movements.

PubMed

Nachev, Parashkev; Husain, Masud; Kennard, Christopher

2008-01-01

Although the conceptual distinction between voluntary and automatic acts seems intuitively obvious, its neural basis remains opaque. Assigning volition--or some paraphrase such as action selection--to discrete parts of the brain arguably tells us nothing about what volition actually is in neural terms. Equally, exploring the relative sensitivity of discrete brain areas to manipulations of action choice, including its asymptote--free choice--would only be informative if voluntary processes could thereby be reliably isolated. Unfortunately, such manipulations are subject to ineliminable confounds, such as the complexity of the underlying condition-action associations. Here we propose an adaptation of a classic oculomotor task--saccadic choice with asynchronous targets--where the processes engaged in free choice manifest as interference in the performance of an automatic task, thereby circumventing the difficulties in parameterising volition. We suggest that this task may be useful in probing deficits in voluntary action in pathological states.

Protective Behaviour of Citizens to Transport Accidents Involving Hazardous Materials: A Discrete Choice Experiment Applied to Populated Areas nearby Waterways

PubMed Central

de Bekker-Grob, Esther W.; Bergstra, Arnold D.; Bliemer, Michiel C. J.; Trijssenaar-Buhre, Inge J. M.; Burdorf, Alex

2015-01-01

Background To improve the information for and preparation of citizens at risk to hazardous material transport accidents, a first important step is to determine how different characteristics of hazardous material transport accidents will influence citizens’ protective behaviour. However, quantitative studies investigating citizens’ protective behaviour in case of hazardous material transport accidents are scarce. Methods A discrete choice experiment was conducted among subjects (19–64 years) living in the direct vicinity of a large waterway. Scenarios were described by three transport accident characteristics: odour perception, smoke/vapour perception, and the proportion of people in the environment that were leaving at their own discretion. Subjects were asked to consider each scenario as realistic and to choose the alternative that was most appealing to them: staying, seeking shelter, or escaping. A panel error component model was used to quantify how different transport accident characteristics influenced subjects’ protective behaviour. Results The response was 44% (881/1,994). The predicted probability that a subject would stay ranged from 1% in case of a severe looking accident till 62% in case of a mild looking accident. All three transport accident characteristics proved to influence protective behaviour. Particularly a perception of strong ammonia or mercaptan odours and visible smoke/vapour close to citizens had the strongest positive influence on escaping. In general, ‘escaping’ was more preferred than ‘seeking shelter’, although stated preference heterogeneity among subjects for these protective behaviour options was substantial. Males were less willing to seek shelter than females, whereas elderly people were more willing to escape than younger people. Conclusion Various characteristics of transport accident involving hazardous materials influence subjects’ protective behaviour. The preference heterogeneity shows that information needs to be targeted differently depending on gender and age to prepare citizens properly. PMID:26571374

The ideal of consumer choice in social services: challenges with implementation in an Ontario injured worker vocational retraining programme.

PubMed

Maceachen, Ellen; Kosny, Agnieszka; Ferrier, Sue; Lippel, Katherine; Neilson, Cynthia; Franche, Renee-Louise; Pugliese, Diana

2013-01-01

Social service programmes that offer consumer choices are intended to guide service efficiency and customer satisfaction. However, little is known about how social service consumers actually make choices and how providers deliver such services. This article details the practical implementation of consumer choice in a Canadian workers' compensation vocational retraining programme. Discourse analysis was conducted of in-depth interviews and focus groups with 71 injured workers and service providers, who discussed their direct experience of a vocational retraining system. Data also included procedural, policy and administrative documents. Consumer choice included workers being offered choices about some service aspects, but not being able to exercise meaningful discretion. Programme cost objectives and restrictive rules and bureaucracy skewed the guidance provided to workers by service providers. If workers did not make the "right" choices, then the service providers were required to make choices for them. This upset workers and created tension for service providers. The ideal of consumer choice in a social service programme was difficult to enact, both for workers and service providers. Processes to increase quality of guidance to social service consumers and to create a systematic feedback look between system designers and consumers are recommended. Implications for Rehabilitation Consumer choice is an increasingly popular concept in social service systems. Vocational case managers can have their own administrative needs and tensions, which do not always align with the client's choices. Rehabilitation programmes need to have processes for considering what choices are important to clients and the resources to support them.

Understanding Health Workers' Job Preferences to Improve Rural Retention in Timor-Leste: Findings from a Discrete Choice Experiment.

PubMed

Smitz, Marc-Francois; Witter, Sophie; Lemiere, Christophe; Eozenou, Patrick Hoang-Vu; Lievens, Tomas; Zaman, Rashid U; Engelhardt, Kay; Hou, Xiaohui

2016-01-01

Timor-Leste built its health workforce up from extremely low levels after its war of independence, with the assistance of Cuban training, but faces challenges as the first cohorts of doctors will shortly be freed from their contracts with government. Retaining doctors, nurses and midwives in remote areas requires a good understanding of health worker preferences. The article reports on a discrete choice experiment (DCE) carried out amongst 441 health workers, including 173 doctors, 150 nurses and 118 midwives. Qualitative methods were conducted during the design phase. The attributes which emerged were wages, skills upgrading/specialisation, location, working conditions, transportation and housing. One of the main findings of the study is the relative lack of importance of wages for doctors, which could be linked to high intrinsic motivation, perceptions of having an already highly paid job (relative to local conditions), and/or being in a relatively early stage of their career for most respondents. Professional development provides the highest satisfaction with jobs, followed by the working conditions. Doctors with less experience, males and the unmarried are more flexible about location. For nurses and midwives, skill upgrading emerged as the most cost effective method. The study is the first of its kind conducted in Timor-Leste. It provides policy-relevant information to balance financial and non-financial incentives for different cadres and profiles of staff. It also augments a thin literature on the preferences of working doctors (as opposed to medical students) in low and middle income countries and provides insights into the ability to instil motivation to work in rural areas, which may be influenced by rural recruitment and Cuban-style training, with its emphasis on community service.

Women's preferences for aspects of labor management: results from a discrete choice experiment.

PubMed

Scotland, Graham S; McNamee, Paul; Cheyne, Helen; Hundley, Vanora; Barnett, Carol

2011-03-01

The latent phase of labor can vary greatly in duration, and many women are uncertain about when to contact the maternity unit. The aim of this study was to elicit and value women's preferences for some aspects of labor management. A questionnaire was sent to 1,251 women who had recently given birth to their first child at one of 14 maternity units in Scotland. Discrete choice questions were used to measure women's preferences for five attributes of care: number of visits (assessments) before admission to the labor ward, time spent on the labor ward before delivery, mobility during labor, pain relief required, and mode of delivery. Responses were analyzed for the sample as a whole and for subgroups defined by recent experiences of labor. A total of 730 (58.4%) questionnaires were returned and analyzed. Women expressed a preference for fewer visits before admission, shorter times on the labor ward before delivery, mobility during labor, normal vaginal deliveries, and moderate forms of pain relief (Entonox and opiates). Subgroup analysis suggests that women's preferences for pain relief are influenced by their recent labor experience. The elicited preference values provide a means for estimating the tradeoffs women are willing to make between attributes of labor management. Women appear to dislike being turned away from the labor ward before admission for delivery. Extra visits before admission only appear to be a price worth paying if they result in reductions in the duration of time spent on the labor ward, reductions in the chance of being immobilized in hospital during labor, or a lower chance of requiring an instrumental or operative delivery. © 2010, Copyright the Authors. Journal compilation © 2010, Wiley Periodicals, Inc.

Patients' preferences for anti-osteoporosis drug treatment: a cross-European discrete choice experiment.

PubMed

Hiligsmann, Mickaël; Dellaert, Benedict G; Dirksen, Carmen D; Watson, Verity; Bours, Sandrine; Goemaere, Stefan; Reginster, Jean-Yves; Roux, Christian; McGowan, Bernie; Silke, Carmel; Whelan, Bryan; Diez-Perez, Adolfo; Torres, Elisa; Papadakis, Georgios; Rizzoli, Rene; Cooper, Cyrus; Pearson, Gill; Boonen, Annelies

2017-07-01

To estimate the preferences of osteoporotic patients for medication attributes, and analyse data from seven European countries. A discrete choice experiment was conducted in Belgium, France, Ireland, the Netherlands, Spain, Switzerland and the UK. Patients were asked to choose repeatedly between two hypothetical unlabelled drug treatments (and an opt-out option) that varied with respect to four attributes: efficacy in reducing the risk of fracture, type of potential common side effects, and mode and frequency of administration. In those countries in which patients contribute to the cost of their treatment directly, a fifth attribute was added: out-of-pocket cost. A mixed logit panel model was used to estimate patients' preferences. In total, 1124 patients completed the experiment, with a sample of between 98 and 257 patients per country. In all countries, patients preferred treatment with higher effectiveness, and 6-monthly subcutaneous injection was always preferred over weekly oral tablets. In five countries, patients also preferred a monthly oral tablet and yearly i.v. injections over weekly oral tablets. In the three countries where the out-of-pocket cost was included as an attribute, lower costs significantly contributed to the treatment preference. Between countries, there were statistically significant differences for 13 out of 42 attribute/level interactions. We found statistically significant differences in patients' preferences for anti-osteoporosis medications between countries, especially for the mode of administration. Our findings emphasized that international treatment recommendations should allow for local adaptation, and that understanding individual preferences is important if we want to improve the quality of clinical care for patients with osteoporosis. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com

How to reform western care payment systems according to physicians, policy makers, healthcare executives and researchers: a discrete choice experiment.

PubMed

Kessels, Roselinde; Van Herck, Pieter; Dancet, Eline; Annemans, Lieven; Sermeus, Walter

2015-05-06

Many developed countries are reforming healthcare payment systems in order to limit costs and improve clinical outcomes. Knowledge on how different groups of professional stakeholders trade off the merits and downsides of healthcare payment systems is limited. Using a discrete choice experiment we asked a sample of physicians, policy makers, healthcare executives and researchers from Canada, Europe, Oceania, and the United States to choose between profiles of hypothetical outcomes on eleven healthcare performance objectives which may arise from a healthcare payment system reform. We used a Bayesian D-optimal design with partial profiles, which enables studying a large number of attributes, i.e. the eleven performance objectives, in the experiment. Our findings suggest that (a) moving from current payment systems to a value-based system is supported by physicians, despite an income trade-off, if effectiveness and long term cost containment improve. (b) Physicians would gain in terms of overall objective fulfillment in Eastern Europe and the US, but not in Canada, Oceania and Western Europe. Finally, (c) such payment reform more closely aligns the overall fulfillment of objectives between stakeholders such as physicians versus healthcare executives. Although the findings should be interpreted with caution due to the potential selection effects of participants, it seems that the value driven nature of newly proposed and/or introduced care payment reforms is more closely aligned with what stakeholders favor in some health systems, but not in others. Future studies, including the use of random samples, should examine the contextual factors that explain such differences in values and buy-in. C90, C99, E61, I11, I18, O57.

Men's preferences and trade-offs for prostate cancer screening: a discrete choice experiment.

PubMed

Howard, Kirsten; Salkeld, Glenn P; Patel, Manish I; Mann, Graham J; Pignone, Michael P

2015-12-01

Prostate cancer screening using prostate-specific antigen (PSA) remains controversial. In deciding about screening, men must weigh the benefits and harms: little is known about benefit: harm trade-offs men are willing to accept. The objective of this study was to assess men's preferences for PSA screening, and the trade-offs between benefits and harms men are willing to accept when deciding about screening. Preferences of 662 men aged 40-69 were assessed using a discrete choice experiment. PSA screening was described by six attributes: prostate cancer deaths, prostate cancer diagnoses, unnecessary biopsies from false-positive PSA tests, impotence, urinary incontinence/bowel problems and cost. A mixed logit model was used to examine the influence of attributes on men's preferences for PSA testing; benefit: harm trade-offs were also calculated. Men's preferences were significantly influenced by test characteristics, particularly potential mortality benefit, unnecessary biopsies and likelihood of urinary incontinence or bowel problems; preferences were also influenced by age, prior PSA testing experience and perceived risk of prostate cancer. Men were willing to accept between 65 and 233 of 10 000 extra men with unnecessary biopsies, and between 31 and 72 of 10 000 extra men with incontinence/bowel problems to avoid one prostate cancer death. Differences in valuations of attributes and trade-offs acceptable to men of different ages suggest a one size fits all approach to PSA testing, regardless of age, may not reflect men's preferences. Our results can be used by policymakers to ensure screening programmes are in line with men's preferences and by clinicians and patients to facilitate informed discussions of the most relevant benefits and downsides of PSA screening for an individual man. © 2014 John Wiley & Sons Ltd.

Using a Discrete-Choice Experiment Involving Cost to Value a Classification System Measuring the Quality-of-Life Impact of Self-Management for Diabetes.

PubMed

Rowen, Donna; Stevens, Katherine; Labeit, Alexander; Elliott, Jackie; Mulhern, Brendan; Carlton, Jill; Basarir, Hasan; Ratcliffe, Julie; Brazier, John

2018-01-01

To describe the use of a novel approach in health valuation of a discrete-choice experiment (DCE) including a cost attribute to value a recently developed classification system for measuring the quality-of-life impact (both health and treatment experience) of self-management for diabetes. A large online survey was conducted using DCE with cost on UK respondents from the general population (n = 1497) and individuals with diabetes (n = 405). The data were modeled using a conditional logit model with robust standard errors. The marginal rate of substitution was used to generate willingness-to-pay (WTP) estimates for every state defined by the classification system. Robustness of results was assessed by including interaction effects for household income. There were some logical inconsistencies and insignificant coefficients for the milder levels of some attributes. There were some differences in the rank ordering of different attributes for the general population and diabetic patients. The WTP to avoid the most severe state was £1118.53 per month for the general population and £2356.02 per month for the diabetic patient population. The results were largely robust. Health and self-management can be valued in a single classification system using DCE with cost. The marginal rate of substitution for key attributes can be used to inform cost-benefit analysis of self-management interventions in diabetes using results from clinical studies in which this new classification system has been applied. The method shows promise, but found large WTP estimates exceeding the cost levels used in the survey. Copyright © 2018 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Understanding Health Workers’ Job Preferences to Improve Rural Retention in Timor-Leste: Findings from a Discrete Choice Experiment

PubMed Central

Smitz, Marc-Francois; Witter, Sophie; Lemiere, Christophe; Eozenou, Patrick Hoang-Vu; Lievens, Tomas; Zaman, Rashid U.; Engelhardt, Kay; Hou, Xiaohui

2016-01-01

Background Timor-Leste built its health workforce up from extremely low levels after its war of independence, with the assistance of Cuban training, but faces challenges as the first cohorts of doctors will shortly be freed from their contracts with government. Retaining doctors, nurses and midwives in remote areas requires a good understanding of health worker preferences. Methods The article reports on a discrete choice experiment (DCE) carried out amongst 441 health workers, including 173 doctors, 150 nurses and 118 midwives. Qualitative methods were conducted during the design phase. The attributes which emerged were wages, skills upgrading/specialisation, location, working conditions, transportation and housing. Findings One of the main findings of the study is the relative lack of importance of wages for doctors, which could be linked to high intrinsic motivation, perceptions of having an already highly paid job (relative to local conditions), and/or being in a relatively early stage of their career for most respondents. Professional development provides the highest satisfaction with jobs, followed by the working conditions. Doctors with less experience, males and the unmarried are more flexible about location. For nurses and midwives, skill upgrading emerged as the most cost effective method. Conclusions The study is the first of its kind conducted in Timor-Leste. It provides policy-relevant information to balance financial and non-financial incentives for different cadres and profiles of staff. It also augments a thin literature on the preferences of working doctors (as opposed to medical students) in low and middle income countries and provides insights into the ability to instil motivation to work in rural areas, which may be influenced by rural recruitment and Cuban-style training, with its emphasis on community service. PMID:27846242

Understanding HIV-positive patients' preferences for healthcare services: a protocol for a discrete choice experiment

PubMed Central

Youssef, Elaney; Cooper, Vanessa; Miners, Alec; Llewellyn, Carrie; Pollard, Alex; Lagarde, Mylene; Sachikonye, Memory; Sabin, Caroline; Foreman, Claire; Perry, Nicky; Nixon, Eileen; Fisher, Martin

2016-01-01

Introduction While the care of HIV-positive patients, including the detection and management of comorbidities, has historically been provided in HIV specialist outpatient clinics, recent years have seen a greater involvement of non-HIV specialists and general practitioners (GPs). The aim of this study is to determine whether patients would prefer to see their GP or HIV physician given general symptoms, and to understand what aspects of care influence their preferences. Methods/analysis We have developed and piloted a discrete choice experiment (DCE) to better understand patients' preferences for care of non-HIV-related acute symptoms. The design of the DCE was informed by our exploratory research, including the findings of a systematic literature review and a qualitative study. Additional questionnaire items have been included to measure demographics, service use and experience of non-HIV illnesses and quality of life (EQ5D). We plan to recruit 1000 patients from 14 HIV clinics across South East England. Data will be analysed using random-effects logistic regression and latent class analysis. ORs and 95% CIs will be used to estimate the relative importance of each of the attribute levels. Latent class analysis will identify whether particular groups of people value the service attribute levels differently. Ethics/dissemination Ethical approval for this study was obtained from the Newcastle and North Tyneside Research Ethics Committee (reference number 14/NE/1193). The results will be disseminated at national and international conferences and peer-reviewed publications. A study report, written in plain English, will be made available to all participants. The Patient Advisory Group will develop a strategy for wider dissemination of the findings to patients and the public. PMID:27431895

Comparing Analytic Hierarchy Process and Discrete-Choice Experiment to Elicit Patient Preferences for Treatment Characteristics in Age-Related Macular Degeneration.

PubMed

Danner, Marion; Vennedey, Vera; Hiligsmann, Mickaël; Fauser, Sascha; Gross, Christian; Stock, Stephanie

2017-09-01

In this study, we conducted an analytic hierarchy process (AHP) and a discrete choice experiment (DCE) to elicit the preferences of patients with age-related macular degeneration using identical attributes and levels. To compare preference-based weights for age-related macular degeneration treatment attributes and levels generated by two elicitation methods. The properties of both methods were assessed, including ease of instrument use. A DCE and an AHP experiment were designed on the basis of five attributes. Preference-based weights were generated using the matrix multiplication method for attributes and levels in AHP and a mixed multinomial logit model for levels in the DCE. Attribute importance was further compared using coefficient (DCE) and weight (AHP) level ranges. The questionnaire difficulty was rated on a qualitative scale. Patients were asked to think aloud while providing their judgments. AHP and DCE generated similar results regarding levels, stressing a preference for visual improvement, frequent monitoring, on-demand and less frequent injection schemes, approved drugs, and mild side effects. Attribute weights derived on the basis of level ranges led to a ranking that was opposite to the AHP directly calculated attribute weights. For example, visual function ranked first in the AHP and last on the basis of level ranges. The results across the methods were similar, with one exception: the directly measured AHP attribute weights were different from the level-based interpretation of attribute importance in both DCE and AHP. The dependence/independence of attribute importance on level ranges in DCE and AHP, respectively, should be taken into account when choosing a method to support decision making. Copyright © 2017 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Delay Discounting in Lewis and Fischer 344 Rats: Steady-State and Rapid-Determination Adjusting-Amount Procedures

ERIC Educational Resources Information Center

Stein, Jeffrey S.; Pinkston, Jonathan W.; Brewer, Adam T.; Francisco, Monica T.; Madden, Gregory J.

2012-01-01

Lewis rats have been shown to make more impulsive choices than Fischer 344 rats in discrete trial choice procedures that arrange fixed (i.e., nontitrating) reinforcement parameters. However, nontitrating procedures yield only gross estimates of preference, as choice measures in animal subjects are rarely graded at the level of the individual…

Preferences, constraints, and the process of sex segregation in college majors: A choice analysis.

PubMed

Ochsenfeld, Fabian

2016-03-01

The persistence of horizontal sex segregation in higher education continues to puzzle social scientists. To help resolve this puzzle, we analyze a sample of college entrants in Germany with a discrete choice design that allows for social learning from the experiences of others. We make at least two contributions to the state of research. First, we test whether essentialist gender stereotypes affect major selection mostly through internalization or rather as external constraints that high school graduates adapt their behavior to. Empirically, we find that internalized vocational interests better explain gendered major choices than conformance with friends' and parents' expectations does. Second, we scrutinize whether segregation results from women's anticipation of gendered family roles or from their anticipation of sex-based discrimination, but we find no evidence for either of these hypotheses. As in most previous studies, differences in mathematics achievement fail to explain gendered patterns of selection into college majors. Copyright © 2016 Elsevier Inc. All rights reserved.

Local-Mesh, Local-Order, Adaptive Finite Element Methods with a Posteriori Error Estimators for Elliptic Partial Differential Equations.

DTIC Science & Technology

1981-12-01

I I I I I o-F--o -- oIl lI I I 0--0------0I Im I I o--G--o ] II I I ...C-0076, the Department of Energy (DOE Grant DE-AC02-77ET53053), The National Science Foundation (Graduate Fellowship), and Yale University. " i o V.IM...element method, the choice of discretization i eft to the user, who must base his decision on experience with similar equations. - In recent years,

Eliciting preferences for social health insurance in Ethiopia: a discrete choice experiment.

PubMed

Obse, Amarech; Ryan, Mandy; Heidenreich, Sebastian; Normand, Charles; Hailemariam, Damen

2016-12-01

As low-income countries are initiating health insurance schemes, Ethiopia is also planning to move away from out-of-pocket private payments to health insurance. The success of such a policy depends on understanding and predicting preferences of potential enrolees. This is because a scarce health care budget forces providers and consumers to make trade-offs between potential benefits within a health insurance. An assessment of preferences of potential enrolees can therefore add important information to optimal resource allocation in the design of health insurance. We used a discrete choice experiment to elicit preferences for social health insurance (SHI) among formal sector employees in Ethiopia. Respondents were presented with 18 binary hypothetical choices of SHI. Each insurance package was described by eight policy relevant attributes: premium, enrolment, exclusions, providers and coverage of inpatient services, outpatient services, drugs and tests. A mixed logit model was estimated to determine respondents' willingness to pay (WTP) for the different health insurance attributes. We also predicted probabilities of uptake for alternative SHI scenarios. Health insurance packages with 'no exclusions', 'public and private' providers, low rate of premium and full coverage of tests and drugs were highly valued and had greatest impact on the choices . Other things being equal, respondents were willing to contribute 1.52% (95% confidence interval (CI): 0.71, 2.32) of their salary to a SHI package with no service exclusions having public and private service providers. This is substantially lower than the proposed 3% premium in the draft SHI strategy. For the typical SHI package proposed by the SHI strategy at the time, the uptake probability was predicted to be 29% (95% CI: 0.25, 0.33). The low uptake probability and WTP for the proposed SHI package suggests considering preferences of the potential enrolees' in revisions of the draft SHI strategy for introduction of optimal SHI scheme would enhance acceptance. © The Author 2016. Published by Oxford University Press in association with The London School of Hygiene and Tropical Medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Investigating the complementary value of discrete choice experiments for the evaluation of barriers and facilitators in implementation research: a questionnaire survey

PubMed Central

van Helvoort-Postulart, Debby; van der Weijden, Trudy; Dellaert, Benedict GC; de Kok, Mascha; von Meyenfeldt, Maarten F; Dirksen, Carmen D

2009-01-01

Background The potential barriers and facilitators to change should guide the choice of implementation strategy. Implementation researchers believe that existing methods for the evaluation of potential barriers and facilitators are not satisfactory. Discrete choice experiments (DCE) are relatively new in the health care sector to investigate preferences, and may be of value in the field of implementation research. The objective of our study was to investigate the complementary value of DCE for the evaluation of barriers and facilitators in implementation research. Methods Clinical subject was the implementation of the guideline for breast cancer surgery in day care. We identified 17 potential barriers and facilitators to the implementation of this guideline. We used a traditional questionnaire that was made up of statements about the potential barriers and facilitators. Respondents answered 17 statements on a five-point scale ranging from one (fully disagree) to five (fully agree). The potential barriers and facilitators were included in the DCE as decision attributes. Data were gathered among anaesthesiologists, surgical oncologists, and breast care nurses by means of a paper-and-pencil questionnaire. Results The overall response was 10%. The most striking finding was that the responses to the traditional questionnaire hardly differentiated between barriers. Forty-seven percent of the respondents thought that DCE is an inappropriate method. These respondents considered DCE too difficult and too time-consuming. Unlike the traditional questionnaire, the results of a DCE provide implementation researchers and clinicians with a relative attribute importance ranking that can be used to prioritize potential barriers and facilitators to change, and hence to better fine-tune the implementation strategies to the specific problems and challenges of a particular implementation process. Conclusion The results of our DCE and traditional questionnaire would probably lead to different implementation strategies. Although there is no 'gold standard' for prioritising potential barriers and facilitators to the implementation of change, theoretically, DCE would be the method of choice. However, the feasibility of using DCE was less favourable. Further empirical applications should investigate whether DCE can really make a valuable contribution to the implementation science. PMID:19250555

A latent class multiple constraint multiple discrete-continuous extreme value model of time use and goods consumption.

DOT National Transportation Integrated Search

2016-06-01

This paper develops a microeconomic theory-based multiple discrete continuous choice model that considers: (a) that both goods consumption and time allocations (to work and non-work activities) enter separately as decision variables in the utility fu...

Investigating Choice Experiments for Preferences of Older People (ICEPOP): evaluative spaces in health economics.

PubMed

Coast, Joanna; Flynn, Terry; Sutton, Eileen; Al-Janabi, Hareth; Vosper, Jane; Lavender, Sarita; Louviere, Jordan; Peters, Tim

2008-10-01

This paper deals with three concerns about the evaluative framework that is currently dominant within health economics. These concerns are: that the evaluative framework is concerned entirely with health; that the evaluative framework has an individualistic focus on patients alone; and that the methods used to estimate 'health' within the current evaluative framework could be improved both in terms of the generation of descriptive systems and in using valuation methods that rely less on people's ability to express their preferences on a cardinal scale. In exploring these issues the Investigating Choice Experiments for Preferences of Older People (ICEPOP) programme has explicitly focused on both the topic of older people and the methods of discrete choice experiments. A capability index has been developed and attributes for an economic measure of end-of-life care are currently being generated, providing the possibility of extending the evaluative framework beyond health alone. A measure of carer's experience and a framework for extending measurement in end-of-life care to loved ones are both also in development, thus extending the evaluative framework beyond the patient alone. Rigorous qualitative methods employing an iterative approach have been developed for use in constructing attributes, and best-worst scaling has been utilized to reduce task complexity and provide insights into heterogeneity. There are a number of avenues for further research in all these areas, but in particular there is need for greater attention to be paid to the theory underlying the evaluative framework within health economics.

Testing Ecological Theories of Offender Spatial Decision Making Using a Discrete Choice Model.

PubMed

Johnson, Shane D; Summers, Lucia

2015-04-01

Research demonstrates that crime is spatially concentrated. However, most research relies on information about where crimes occur, without reference to where offenders reside. This study examines how the characteristics of neighborhoods and their proximity to offender home locations affect offender spatial decision making. Using a discrete choice model and data for detected incidents of theft from vehicles (TFV) , we test predictions from two theoretical perspectives-crime pattern and social disorganization theories. We demonstrate that offenders favor areas that are low in social cohesion and closer to their home, or other age-related activity nodes. For adult offenders, choices also appear to be influenced by how accessible a neighborhood is via the street network. The implications for criminological theory and crime prevention are discussed.

Testing Ecological Theories of Offender Spatial Decision Making Using a Discrete Choice Model

PubMed Central

Summers, Lucia

2015-01-01

Research demonstrates that crime is spatially concentrated. However, most research relies on information about where crimes occur, without reference to where offenders reside. This study examines how the characteristics of neighborhoods and their proximity to offender home locations affect offender spatial decision making. Using a discrete choice model and data for detected incidents of theft from vehicles (TFV), we test predictions from two theoretical perspectives—crime pattern and social disorganization theories. We demonstrate that offenders favor areas that are low in social cohesion and closer to their home, or other age-related activity nodes. For adult offenders, choices also appear to be influenced by how accessible a neighborhood is via the street network. The implications for criminological theory and crime prevention are discussed. PMID:25866412

Modelling discrete choice variables in assessment of teaching staff work satisfaction.

PubMed

Mieilă, Mihai; Popescu, Constanţa; Tudorache, Ana-Maria; Toplicianu, Valerică

2015-01-01

Levels of self-reported job satisfaction and motivation were measured by survey in a sample of 286 teachers. Using the discrete choice framework, the paper tries to assess the relevance of the considered indicators (demographic, social, motivational) in overall teaching work satisfaction. The findings provide evidence that job satisfaction is correlated significantly with level of university degree held by the teacher, type of secondary school where the teacher is enrolled, revenues, and salary-tasks adequacy. This is important for the Romanian economy, since the education system is expected to provide future human resources with enhanced skills and abilities.

Modelling Discrete Choice Variables in Assessment of Teaching Staff Work Satisfaction

PubMed Central

2015-01-01

Levels of self-reported job satisfaction and motivation were measured by survey in a sample of 286 teachers. Using the discrete choice framework, the paper tries to assess the relevance of the considered indicators (demographic, social, motivational) in overall teaching work satisfaction. The findings provide evidence that job satisfaction is correlated significantly with level of university degree held by the teacher, type of secondary school where the teacher is enrolled, revenues, and salary-tasks adequacy. This is important for the Romanian economy, since the education system is expected to provide future human resources with enhanced skills and abilities. PMID:25849295

Some unsolved problems in discrete mathematics and mathematical cybernetics

NASA Astrophysics Data System (ADS)

Korshunov, Aleksei D.

2009-10-01

There are many unsolved problems in discrete mathematics and mathematical cybernetics. Writing a comprehensive survey of such problems involves great difficulties. First, such problems are rather numerous and varied. Second, they greatly differ from each other in degree of completeness of their solution. Therefore, even a comprehensive survey should not attempt to cover the whole variety of such problems; only the most important and significant problems should be reviewed. An impersonal choice of problems to include is quite hard. This paper includes 13 unsolved problems related to combinatorial mathematics and computational complexity theory. The problems selected give an indication of the author's studies for 50 years; for this reason, the choice of the problems reviewed here is, to some extent, subjective. At the same time, these problems are very difficult and quite important for discrete mathematics and mathematical cybernetics. Bibliography: 74 items.

Iterative Potts and Blake–Zisserman minimization for the recovery of functions with discontinuities from indirect measurements

PubMed Central

Weinmann, Andreas; Storath, Martin

2015-01-01

Signals with discontinuities appear in many problems in the applied sciences ranging from mechanics, electrical engineering to biology and medicine. The concrete data acquired are typically discrete, indirect and noisy measurements of some quantities describing the signal under consideration. The task is to restore the signal and, in particular, the discontinuities. In this respect, classical methods perform rather poor, whereas non-convex non-smooth variational methods seem to be the correct choice. Examples are methods based on Mumford–Shah and piecewise constant Mumford–Shah functionals and discretized versions which are known as Blake–Zisserman and Potts functionals. Owing to their non-convexity, minimization of such functionals is challenging. In this paper, we propose a new iterative minimization strategy for Blake–Zisserman as well as Potts functionals and a related jump-sparsity problem dealing with indirect, noisy measurements. We provide a convergence analysis and underpin our findings with numerical experiments. PMID:27547074

An enquiry into the method of paired comparison: reliability, scaling, and Thurstone's Law of Comparative Judgment

Treesearch

Thomas C. Brown; George L. Peterson

2009-01-01

The method of paired comparisons is used to measure individuals' preference orderings of items presented to them as discrete binary choices. This paper reviews the theory and application of the paired comparison method, describes a new computer program available for eliciting the choices, and presents an analysis of methods for scaling paired choice data to...

Impact of falling reimbursement rates on physician preferences regarding drug therapy for osteoarthritis using a discrete choice experiment.

PubMed

Berchi, Celia; Degieux, Pierre; Halhol, Hafid; Danel, Brigitte; Bennani, Mohammed; Philippe, Caroline

2016-04-01

In the European context of falling reimbursement rates for some osteoarthritis (OA) treatments, we performed a study to determine whether the cost covered by patients influenced the decisions of their physicians' prescriptions for medication. The study involved 106 general practitioners (GPs) and 82 rheumatologists. Preferences were elicited using a discrete choice experiment. Scenarios were generated including seven treatment attributes with associated different levels: pain relief, improvement in function, retardation of joint degradation, risk of moderate side effects, risk of serious side effects, cost borne by the patient and degree of patient acceptance of the treatment. OA treatment choices were significantly influenced by pain relief (β = 1.1533, P < 0.0001 for GPs and β = 0.5043, P = 0.0024 for rheumatologists), improvement in function (β = 1.2140 for GPs and β = 0.7192 for rheumatologists, P < 0.0001), annual cost to the patient (β = -0.0054 for GPs and β = -0.0038 for rheumatologists, P < 0.0001) and serious side effects (β = -0.5524 for GPs and β = -0.4268 for rheumatologists, P < 0.0001). The risk of moderate side effects only had an impact on GP decision making (β = 0.0282, P = 0.0028). All physicians were willing to make patients bear an extra annual cost of: (1) €225 among GPs and €189 among rheumatologists so that they could benefit from one unit improvement in function; and (2) €214 among GPs and €133 among rheumatologists so that they could benefit from a one unit improvement in pain relief. When making decisions about which treatment to prescribe, physicians take into account the cost to patients. Changes in reimbursement rates for some OA treatments may lead to changes in prescribing practices. © 2015 Royal Pharmaceutical Society.

What influences persistence with medicines? A multinational discrete choice experiment of 2549 patients.

PubMed

Holmes, Emily A F; Morrison, Valerie L; Hughes, Dyfrig A

2016-08-01

The aim was to examine patients' stated preferences to persist with medicines and to explore the influence of psychosocial and sociocognitive factors. Community-dwelling, hypertensive patients recruited from nine European countries were invited to complete a discrete choice experiment (DCE) with attributes for treatment benefits, mild yet common adverse drug reactions (ADRs), rare but potentially life-threatening ADRs and dosing frequency. Patients responded to the binary choice of which medicine would they be most likely to continue taking. Data were analyzed using a random effects logit model. Two thousand five hundred and forty-nine patients from Austria (n = 321), Belgium (n = 175), England (n = 315), Germany (n = 266), Greece (n = 288), Hungary (n = 322), the Netherlands (n = 231), Poland (n = 312) and Wales (n = 319) completed the DCE. All attributes significantly influenced patients' stated preference to persist with medications (P < 0.05). Patients were willing to accept decreases in treatment benefits of 50.6 percentage points (95% CI 46.1, 57.9) for a very rare (as opposed to rare) risk of severe ADR, 28.3 percentage points (95% CI 25.2, 33.1) for a once daily instead of twice daily dosing and 0.74 percentage points (95% CI 0.67, 0.85) for a 1% point reduction in mild ADRs. Models accounting for psychosocial and sociocognitive characteristics were significantly different from the base case. Patients' intention to persist with treatment was associated with their willingness to trade potential benefits, harms and dosing frequency. Psychosocial and sociocognitive factors influenced the extent of trading. The utility model may have value in assessing patients' likelihood of persisting with medicines and to tailor treatment to maximize persistence. © 2016 The British Pharmacological Society.

Investigating the impact of design characteristics on statistical efficiency within discrete choice experiments: A systematic survey.

PubMed

Vanniyasingam, Thuva; Daly, Caitlin; Jin, Xuejing; Zhang, Yuan; Foster, Gary; Cunningham, Charles; Thabane, Lehana

2018-06-01

This study reviews simulation studies of discrete choice experiments to determine (i) how survey design features affect statistical efficiency, (ii) and to appraise their reporting quality. Statistical efficiency was measured using relative design (D-) efficiency, D-optimality, or D-error. For this systematic survey, we searched Journal Storage (JSTOR), Since Direct, PubMed, and OVID which included a search within EMBASE. Searches were conducted up to year 2016 for simulation studies investigating the impact of DCE design features on statistical efficiency. Studies were screened and data were extracted independently and in duplicate. Results for each included study were summarized by design characteristic. Previously developed criteria for reporting quality of simulation studies were also adapted and applied to each included study. Of 371 potentially relevant studies, 9 were found to be eligible, with several varying in study objectives. Statistical efficiency improved when increasing the number of choice tasks or alternatives; decreasing the number of attributes, attribute levels; using an unrestricted continuous "manipulator" attribute; using model-based approaches with covariates incorporating response behaviour; using sampling approaches that incorporate previous knowledge of response behaviour; incorporating heterogeneity in a model-based design; correctly specifying Bayesian priors; minimizing parameter prior variances; and using an appropriate method to create the DCE design for the research question. The simulation studies performed well in terms of reporting quality. Improvement is needed in regards to clearly specifying study objectives, number of failures, random number generators, starting seeds, and the software used. These results identify the best approaches to structure a DCE. An investigator can manipulate design characteristics to help reduce response burden and increase statistical efficiency. Since studies varied in their objectives, conclusions were made on several design characteristics, however, the validity of each conclusion was limited. Further research should be conducted to explore all conclusions in various design settings and scenarios. Additional reviews to explore other statistical efficiency outcomes and databases can also be performed to enhance the conclusions identified from this review.

Renal transplant patients' preference for the supply and delivery of immunosuppressants in Wales: a discrete choice experiment.

PubMed

Hagemi, Anke; Plumpton, Catrin; Hughes, Dyfrig A

2017-10-02

Prescribing policy recommendations aimed at moving immunosuppressant prescribing for renal transplant patients from primary to secondary care may result in benefits of increased safety and reduced cost. However, there is little evidence of patients' preferences for receiving their immunosuppressant therapy from hospitals compared to community dispensing. The aim of this study was to elicit patient preferences for different service configurations focusing in particular on home delivery versus collection of medication from hospital. A discrete choice experiment was administered to 265 renal transplant patients in North Wales. Respondents were presented 18 pairwise choices, labelled as either home delivery or hospital collection, and described by the attributes: frequency of supply, waiting time (for delivery or collection) and method of ordering (provider contact, patient contact via phone, patient contact electronically). Data were analysed using a random-effects logit model and marginal rates of substitution calculated based on the waiting time attribute. A response rate of 63% was achieved, with 5332 usable observations from 150 respondents. Method of delivery (β coefficient 1.21; 95% confidence interval 1.05 to 1.38), frequency of supply (0.05; 0.03 to 0.08) waiting time (-0.00, -0.00 to -0.00), provider contact (desirable) (0.20; 0.12 to 0.27), patient contact by telephone (desirable) (0.09; 0.01 to 0.17) and patient contact electronically (undesirable) (-0.292; -0.37 to -0.21) were statistically significant (p < 0.05). Results indicate that patients are willing to increase waiting time by nearly 10 h to have a home delivery service. Patients indicate a clear preference for a home delivery service. They prefer providers to make contact when new immunosuppressant supplies are required and show preference against ordering medication electronically. A policy for secondary care prescribing and hospital collection of medicines does not align with this preference.

Job Preferences of Nurses and Midwives for Taking Up a Rural Job in Peru: A Discrete Choice Experiment

PubMed Central

Huicho, Luis; Miranda, J. Jaime; Diez-Canseco, Francisco; Lema, Claudia; Lescano, Andrés G.; Lagarde, Mylene; Blaauw, Duane

2012-01-01

Background Robust evidence on interventions to improve the shortage of health workers in rural areas is needed. We assessed stated factors that would attract short-term contract nurses and midwives to work in a rural area of Peru. Methods and Findings A discrete choice experiment (DCE) was conducted to evaluate the job preferences of nurses and midwives currently working on a short-term contract in the public sector in Ayacucho, Peru. Job attributes, and their levels, were based on literature review, qualitative interviews and focus groups of local health personnel and policy makers. A labelled design with two choices, rural community or Ayacucho city, was used. Job attributes were tailored to these settings. Multiple conditional logistic regressions were used to assess the determinants of job preferences. Then we used the best-fitting estimated model to predict the impact of potential policy incentives on the probability of choosing a rural job or a job in Ayacucho city. We studied 205 nurses and midwives. The odds of choosing an urban post was 14.74 times than that of choosing a rural one. Salary increase, health center-type of facility and scholarship for specialization were preferred attributes for choosing a rural job. Increased number of years before securing a permanent contract acted as a disincentive for both rural and urban jobs. Policy simulations showed that the most effective attraction package to uptake a rural job included a 75% increase in salary plus scholarship for a specialization, which would increase the proportion of health workers taking a rural job from 36.4% up to 60%. Conclusions Urban jobs were more strongly preferred than rural ones. However, combined financial and non-financial incentives could almost double rural job uptake by nurses and midwifes. These packages may provide meaningful attraction strategies to rural areas and should be considered by policy makers for implementation. PMID:23284636

Preferences for working in rural clinics among trainee health professionals in Uganda: a discrete choice experiment.

PubMed

Rockers, Peter C; Jaskiewicz, Wanda; Wurts, Laura; Kruk, Margaret E; Mgomella, George S; Ntalazi, Francis; Tulenko, Kate

2012-07-23

Health facilities require teams of health workers with complementary skills and responsibilities to efficiently provide quality care. In low-income countries, failure to attract and retain health workers in rural areas reduces population access to health services and undermines facility performance, resulting in poor health outcomes. It is important that governments consider health worker preferences in crafting policies to address attraction and retention in underserved areas. We investigated preferences for job characteristics among final year medical, nursing, pharmacy, and laboratory students at select universities in Uganda. Participants were administered a cadre-specific discrete choice experiment that elicited preferences for attributes of potential job postings they were likely to pursue after graduation. Job attributes included salary, facility quality, housing, length of commitment, manager support, training tuition, and dual practice opportunities. Mixed logit models were used to estimate stated preferences for these attributes. Data were collected from 246 medical students, 132 nursing students, 50 pharmacy students and 57 laboratory students. For all student-groups, choice of job posting was strongly influenced by salary, facility quality and manager support, relative to other attributes. For medical and laboratory students, tuition support for future training was also important, while pharmacy students valued opportunities for dual practice. In Uganda, financial and non-financial incentives may be effective in attracting health workers to underserved areas. Our findings contribute to mounting evidence that salary is not the only important factor health workers consider when deciding where to work. Better quality facilities and supportive managers were important to all students. Similarities in preferences for these factors suggest that team-based, facility-level strategies for attracting health workers may be appropriate. Improving facility quality and training managers to be more supportive of facility staff may be particularly cost-effective, as investments are borne once while benefits accrue to a range of health workers at the facility.

Factors affecting residency rank-listing: a Maxdiff survey of graduating Canadian medical students.

PubMed

Wang, Tao; Wong, Benson; Huang, Alexander; Khatri, Prateek; Ng, Carly; Forgie, Melissa; Lanphear, Joel H; O'Neill, Peter J

2011-08-25

In Canada, graduating medical students consider many factors, including geographic, social, and academic, when ranking residency programs through the Canadian Residency Matching Service (CaRMS). The relative significance of these factors is poorly studied in Canada. It is also unknown how students differentiate between their top program choices. This survey study addresses the influence of various factors on applicant decision making. Graduating medical students from all six Ontario medical schools were invited to participate in an online survey available for three weeks prior to the CaRMS match day in 2010. Max-Diff discrete choice scaling, multiple choice, and drop-list style questions were employed. The Max-Diff data was analyzed using a scaled simple count method. Data for how students distinguish between top programs was analyzed as percentages. Comparisons were made between male and female applicants as well as between family medicine and specialist applicants; statistical significance was determined by the Mann-Whitney test. In total, 339 of 819 (41.4%) eligible students responded. The variety of clinical experiences and resident morale were weighed heavily in choosing a residency program; whereas financial incentives and parental leave attitudes had low influence. Major reasons that applicants selected their first choice program over their second choice included the distance to relatives and desirability of the city. Both genders had similar priorities when selecting programs. Family medicine applicants rated the variety of clinical experiences more importantly; whereas specialty applicants emphasized academic factors more. Graduating medical students consider program characteristics such as the variety of clinical experiences and resident morale heavily in terms of overall priority. However, differentiation between their top two choice programs is often dependent on social/geographic factors. The results of this survey will contribute to a better understanding of the CaRMS decision making process for both junior medical students and residency program directors.

Discrete choice experiments in pharmacy: a review of the literature.

PubMed

Naik-Panvelkar, Pradnya; Armour, Carol; Saini, Bandana

2013-02-01

Discrete choice experiments (DCEs) have been widely used to elicit patient preferences for various healthcare services and interventions. The aim of our study was to conduct an in-depth scoping review of the literature and provide a current overview of the progressive application of DCEs within the field of pharmacy. Electronic databases (MEDLINE, EMBASE, SCOPUS, ECONLIT) were searched (January 1990-August 2011) to identify published English language studies using DCEs within the pharmacy context. Data were abstracted with respect to DCE methodology and application to pharmacy. Our search identified 12 studies. The DCE methodology was utilised to elicit preferences for different aspects of pharmacy products, therapy or services. Preferences were elicited from either patients or pharmacists, with just two studies incorporating the views of both. Most reviewed studies examined preferences for process-related or provider-related aspects with a lesser focus on health outcomes. Monetary attributes were considered to be important by most patients and pharmacists in the studies reviewed. Logit, probit or multinomial logit models were most commonly employed for estimation. Our study showed that the pharmacy profession has adopted the DCE methodology consistent with the general health DCEs although the number of studies is quite limited. Future studies need to examine preferences of both patients and providers for particular products or disease-state management services. Incorporation of health outcome attributes in the design, testing for external validity and the incorporation of DCE results in economic evaluation framework to inform pharmacy policy remain important areas for future research. © 2012 The Authors. IJPP © 2012 Royal Pharmaceutical Society.

Using a Discrete Choice Conjoint Experiment to Engage Stakeholders in the Design of an Outpatient Children's Health Center.

PubMed

Cunningham, Charles E; Niccols, Alison; Rimas, Heather; Robicheau, Randi; Anderson, Colleen; DeVries, Bart

2017-10-01

To engage users in the design of a regional child and youth health center. The perspective of users should be an integral component of a patient-centered, evidence-based approach to the design of health facilities. We conducted a discrete choice conjoint experiment (DCE), a method from marketing research and health economics, as a component of a strategy to engage users in the preconstruction planning process. A sample of 467 participants (290 staff and 177 clients or community stakeholders) completed the DCE. Latent class analysis identified three segments with different design preferences. A group we termed an enhanced design (57%) segment preferred a fully featured facility with personal contacts at the start of visits (in-person check-in, personal waiting room notification, volunteer-assisted wayfinding, and visible security), a family resource center with a health librarian, and an outdoor playground equipped with covered heated pathways. The self-guided design segment (11%), in contrast, preferred a design allowing a more independent use of the facility (e.g., self-check-in at computer kiosks, color-coded wayfinding, and a self-guided family resource center). Designs affording privacy and personal contact with staff were important to the private design segment (32%). The theme and decor of the building was less important than interactive features and personal contacts. A DCE allowed us to engage users in the planning process by estimating the value of individual design elements, identifying segments with differing views, informing decisions regarding design trade-offs, and simulating user response to design options.

Is the Nintendo Wii Fit really acceptable to older people?: a discrete choice experiment

PubMed Central

2011-01-01

Background Interactive video games such as the Nintendo Wii Fit are increasingly used as a therapeutic tool in health and aged care settings however, their acceptability to older people is unclear. The aim of this study was to determine the acceptability of the Nintendo Wii Fit as a therapy tool for hospitalised older people using a discrete choice experiment (DCE) before and after exposure to the intervention. Methods A DCE was administered to 21 participants in an interview style format prior to, and following several sessions of using the Wii Fit in physiotherapy. The physiotherapist prescribed the Wii Fit activities, supervised and supported the patient during the therapy sessions. Attributes included in the DCE were: mode of therapy (traditional or using the Wii Fit), amount of therapy, cost of therapy program and percentage of recovery made. Data was analysed using conditional (fixed-effects) logistic regression. Results Prior to commencing the therapy program participants were most concerned about therapy time (avoiding programs that were too intensive), and the amount of recovery they would make. Following the therapy program, participants were more concerned with the mode of therapy and preferred traditional therapy programs over programs using the Wii Fit. Conclusions The usefulness of the Wii Fit as a therapy tool with hospitalised older people is limited not only by the small proportion of older people who are able to use it, but by older people's preferences for traditional approaches to therapy. Mainstream media portrayals of the popularity of the Wii Fit with older people may not reflect the true acceptability in the older hospitalised population. PMID:22011360

Allocating external financing for health: a discrete choice experiment of stakeholder preferences.

PubMed

Grépin, Karen A; Pinkstaff, Crossley B; Hole, Arne Risa; Henderson, Klara; Norheim, Ole Frithjof; Røttingen, John-Arne; Ottersen, Trygve

2018-02-01

Most donors of external financing for health use allocation policies to determine which countries are eligible to receive financial support and how much support each should receive. Currently, most of these policies place a great deal of weight on income per capita as a determinant of aid allocation but there is increasing interest in putting more weight on other country characteristics in the design of such policies. It is unclear, however, how much weight should be placed on other country characteristics. Using an online discrete choice experiment designed to elicit preferences over country characteristics to guide decisions about the allocation of external financing for health, we find that stakeholders assign a great deal of importance to health inequalities and the burden of disease but put very little weight on income per capita. We also find considerable variation in preferences across stakeholders, with people from low- and middle-income countries putting more weight on the burden of disease and people from high-income countries putting more weight on health inequalities. These findings suggest that stakeholders put more weight on burden of disease and health inequalities than on income per capita in evaluating which countries should received external financing for health and that that people living in aid recipient may have different preferences than people living in donor countries. Donors may wish to take these differences in preferences in mind if they are reconsidering their aid allocation policies. © The Author(s) 2018. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

An Empirical Comparison of Discrete Choice Experiment and Best-Worst Scaling to Estimate Stakeholders' Risk Tolerance for Hip Replacement Surgery.

PubMed

van Dijk, Joris D; Groothuis-Oudshoorn, Catharina G M; Marshall, Deborah A; IJzerman, Maarten J

2016-06-01

Previous studies have been inconclusive regarding the validity and reliability of preference elicitation methods. The aim of this study was to compare the metrics obtained from a discrete choice experiment (DCE) and profile-case best-worst scaling (BWS) with respect to hip replacement. We surveyed the general US population of men aged 45 to 65 years, and potentially eligible for hip replacement surgery. The survey included sociodemographic questions, eight DCE questions, and twelve BWS questions. Attributes were the probability of a first and second revision, pain relief, ability to participate in sports and perform daily activities, and length of hospital stay. Conditional logit analysis was used to estimate attribute weights, level preferences, and the maximum acceptable risk (MAR) for undergoing revision surgery in six hypothetical treatment scenarios with different attribute levels. A total of 429 (96%) respondents were included. Comparable attribute weights and level preferences were found for both BWS and DCE. Preferences were greatest for hip replacement surgery with high pain relief and the ability to participate in sports and perform daily activities. Although the estimated MARs for revision surgery followed the same trend, the MARs were systematically higher in five of the six scenarios using DCE. This study confirms previous findings that BWS or DCEs are comparable in estimating attribute weights and level preferences. However, the risk tolerance threshold based on the estimation of MAR differs between these methods, possibly leading to inconsistency in comparing treatment scenarios. Copyright © 2016 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Valuing EQ-5D-5L health states 'in context' using a discrete choice experiment.

PubMed

Cole, Amanda; Shah, Koonal; Mulhern, Brendan; Feng, Yan; Devlin, Nancy

2018-05-01

In health state valuation studies, health states are typically presented as a series of sentences, each describing a health dimension and severity 'level'. Differences in the severity levels can be subtle, and confusion about which is 'worse' can lead to logically inconsistent valuation data. A solution could be to mimic the way patients self-report health, where the ordinal structure of levels is clear. We develop and test the feasibility of presenting EQ-5D-5L health states in the 'context' of the entire EQ-5D-5L descriptive system. An online two-arm discrete choice experiment was conducted in the UK (n = 993). Respondents were randomly allocated to a control (standard presentation) or 'context' arm. Each respondent completed 16 paired comparison tasks and feedback questions about the tasks. Differences across arms were assessed using regression analyses. Presenting health states 'in context' can significantly reduce the selection of logically dominated health states, particularly for labels 'severe' and 'extreme' (χ 2  = 46.02, p < 0.001). Preferences differ significantly between arms (likelihood ratio statistic = 42.00, p < 0.05). Comparing conditional logit modeling results, coefficients are ordered as expected for both arms, but the magnitude of decrements between levels is larger for the context arm. Health state presentation is a key consideration in the design of valuation studies. Presenting health states 'in context' affects valuation data and reduces logical inconsistencies. Our results could have implications for other valuation tasks such as time trade-off, and for the valuation of other preference-based measures.

Citizen Participation in Patient Prioritization Policy Decisions: An Empirical and Experimental Study on Patients' Characteristics

PubMed Central

Diederich, Adele; Swait, Joffre; Wirsik, Norman

2012-01-01

Health systems worldwide are grappling with the need to control costs to maintain system viability. With the combination of worsening economic conditions, an aging population and reductions in tax revenues, the pressures to make structural changes are expected to continue growing. Common cost control mechanisms, e.g. curtailment of patient access and treatment prioritization, are likely to be adversely viewed by citizens. It seems therefore wise to include them in the decision making processes that lead up to policy changes. In the context of a multilevel iterative mixed-method design a quantitative survey representative of the German population (N = 2031) was conducted to probe the acceptance of priority setting in medicine and to explore the practicability of direct public involvement. Here we focus on preferences for patients' characteristics (medical aspects, lifestyle and socio-economic status) as possible criteria for prioritizing medical services. A questionnaire with closed response options was fielded to gain insight into attitudes toward broad prioritization criteria of patient groups. Furthermore, a discrete choice experiment was used as a rigorous approach to investigate citizens' preferences toward specific criteria level in context of other criteria. Both the questionnaire and the discrete choice experiment were performed with the same sample. The citizens' own health and social situation are included as explanatory variables. Data were evaluated using corresponding analysis, contingency analysis, logistic regression and a multinomial exploded logit model. The results show that some medical criteria are highly accepted for prioritizing patients whereas socio-economic criteria are rejected. PMID:22590619

Farmers' valuation of incentives to produce genetically modified organism-free milk: Insights from a discrete choice experiment in Germany.

PubMed

Schreiner, J A; Latacz-Lohmann, U

2015-11-01

This paper investigates farmers' willingness to participate in a genetically modified organism (GMO)-free milk production scheme offered by some German dairy companies. The empirical analysis is based upon discrete choice experiments with 151 dairy farmers from 2 regions in Germany. A conditional logit estimation reveals a strong positive effect of the price premium on offer. Reliable feed monitoring and free technical support increase the likelihood of scheme adoption, the latter however only in farms that have been receiving technical support in other fields. By contrast, any interference with the entrepreneurial autonomy of farmers, through pre-arranged feed procurement or prescriptive advice on the part of the dairy company, lowers acceptance probabilities. Farmers' attitudes toward cultivation of genetically modified soy, their assessment of the market potential of GMO-free milk and future feed prices were found to be significant determinants of adoption, as are farmer age, educational status, and current feeding regimens. Respondents requested on average a mark-up of 0.80 eurocents per kilogram of milk to accept a contract. Comparison of the estimates for the 2 regions suggests that farmers in northern Germany are, on average, more likely to convert to genetically modified-free production; however, farmers in the south are, ceteris paribus, more responsive to an increase in the price premium offered. A latent class model reveals significant differences in the valuation of scheme attributes between 2 latent classes of adopters and nonadopters. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Generalized Reduction Formula for Discrete Wigner Functions of Multiqubit Systems

NASA Astrophysics Data System (ADS)

Srinivasan, K.; Raghavan, G.

2018-03-01

Density matrices and Discrete Wigner Functions are equally valid representations of multiqubit quantum states. For density matrices, the partial trace operation is used to obtain the quantum state of subsystems, but an analogous prescription is not available for discrete Wigner Functions. Further, the discrete Wigner function corresponding to a density matrix is not unique but depends on the choice of the quantum net used for its reconstruction. In the present work, we derive a reduction formula for discrete Wigner functions of a general multiqubit state which works for arbitrary quantum nets. These results would be useful for the analysis and classification of entangled states and the study of decoherence purely in a discrete phase space setting and also in applications to quantum computing.

Dynamic Response-by-Response Models of Matching Behavior in Rhesus Monkeys

PubMed Central

Lau, Brian; Glimcher, Paul W

2005-01-01

We studied the choice behavior of 2 monkeys in a discrete-trial task with reinforcement contingencies similar to those Herrnstein (1961) used when he described the matching law. In each session, the monkeys experienced blocks of discrete trials at different relative-reinforcer frequencies or magnitudes with unsignalled transitions between the blocks. Steady-state data following adjustment to each transition were well characterized by the generalized matching law; response ratios undermatched reinforcer frequency ratios but matched reinforcer magnitude ratios. We modelled response-by-response behavior with linear models that used past reinforcers as well as past choices to predict the monkeys' choices on each trial. We found that more recently obtained reinforcers more strongly influenced choice behavior. Perhaps surprisingly, we also found that the monkeys' actions were influenced by the pattern of their own past choices. It was necessary to incorporate both past reinforcers and past choices in order to accurately capture steady-state behavior as well as the fluctuations during block transitions and the response-by-response patterns of behavior. Our results suggest that simple reinforcement learning models must account for the effects of past choices to accurately characterize behavior in this task, and that models with these properties provide a conceptual tool for studying how both past reinforcers and past choices are integrated by the neural systems that generate behavior. PMID:16596980

Investigating attribute non-attendance and its consequences in choice experiments with latent class models.

PubMed

Lagarde, Mylene

2013-05-01

A growing literature, mainly from transport and environment economics, has started to explore whether respondents violate some of the axioms about individuals' preferences in Discrete Choice Experiments (DCEs) and use simple strategies to make their choices. One of these strategies, termed attribute non-attendance (ANA), consists in ignoring one or more attributes. Using data from a DCE administered to healthcare providers in Ghana to evaluate their potential resistance to changes in clinical guidelines, this study illustrates how latent class models can be used in a step-wise approach to account for all possible ANA strategies used by respondents and explore the consequences of such behaviours. Results show that less than 3% of respondents considered all attributes when choosing between the two hypothetical scenarios proposed, with a majority looking at only one or two attributes. Accounting for ANA strategies improved the goodness-of-fit of the model and affected the magnitude of some of the coefficient and willingness-to-pay estimates. However, there was no difference in the predicted probabilities of the model taking into account ANA and the standard approach. Although the latter result is reassuring about the ability of DCEs to produce unbiased policy guidance, it should be confirmed by other studies. Copyright © 2012 John Wiley & Sons, Ltd.

Pros and cons of conjoint analysis of discrete choice experiments to define classification and response criteria in rheumatology.

PubMed

Taylor, William J

2016-03-01

Conjoint analysis of choice or preference data has been used in marketing for over 40 years but has appeared in healthcare settings much more recently. It may be a useful technique for applications within the rheumatology field. Conjoint analysis in rheumatology contexts has mainly used the approaches implemented in 1000Minds Ltd, Dunedin, New Zealand, Sawtooth Software, Orem UT, USA. Examples include classification criteria, composite response criteria, service prioritization tools and utilities assessment. Limitations imposed by very many attributes can be managed using new techniques. Conjoint analysis studies of classification and response criteria suggest that the assumption of equal weighting of attributes cannot be met, which challenges traditional approaches to composite criteria construction. Weights elicited through choice experiments with experts can derive more accurate classification criteria, than unweighted criteria. Studies that find significant variation in attribute weights for composite response criteria for gout make construction of such criteria problematic. Better understanding of various multiattribute phenomena is likely to increase with increased use of conjoint analysis, especially when the attributes concern individual perceptions or opinions. In addition to classification criteria, some applications for conjoint analysis that are emerging in rheumatology include prioritization tools, remission criteria, and utilities for life areas.

Channeling Consumers to Preferred Providers and the Impact of Status Quo Bias: Does Type of Provider Matter?

PubMed Central

Boonen, Lieke H H M; Donkers, Bas; Schut, Frederik T

2011-01-01

Context To effectively bargain about the price and quality of health services, health insurers need to successfully channel their enrollees. Little is known about consumer sensitivity to different channeling incentives. In particular, the impact of status quo bias, which is expected to differ between different provider types, can play a large role in insurers' channeling ability. Objective To examine consumer sensitivity to channeling strategies and to analyze the impact of status quo bias for different provider types. Data Sources/Study Design With a large-scale discrete choice experiment, we investigate the impact of channeling incentives on choices for pharmacies and general practitioners (GPs). Survey data were obtained among a representative Dutch household panel (n=2,500). Principal Findings Negative financial incentives have a two to three times larger impact on provider choice than positive ones. Positive financial incentives have a relatively small impact on GP choice, while the impact of qualitative incentives is relatively large. Status quo bias has a large impact on provider choice, which is more prominent in the case of GPs than in the case of pharmacies. Conclusion The large impact of the status quo bias makes channeling consumers away from their current providers a daunting task, particularly in the case of GPs. PMID:21029092

Channeling consumers to preferred providers and the impact of status quo bias: does type of provider matter?

PubMed

Boonen, Lieke H H M; Donkers, Bas; Schut, Frederik T

2011-04-01

To effectively bargain about the price and quality of health services, health insurers need to successfully channel their enrollees. Little is known about consumer sensitivity to different channeling incentives. In particular, the impact of status quo bias, which is expected to differ between different provider types, can play a large role in insurers' channeling ability. To examine consumer sensitivity to channeling strategies and to analyze the impact of status quo bias for different provider types. With a large-scale discrete choice experiment, we investigate the impact of channeling incentives on choices for pharmacies and general practitioners (GPs). Survey data were obtained among a representative Dutch household panel (n = 2,500). Negative financial incentives have a two to three times larger impact on provider choice than positive ones. Positive financial incentives have a relatively small impact on GP choice, while the impact of qualitative incentives is relatively large. Status quo bias has a large impact on provider choice, which is more prominent in the case of GPs than in the case of pharmacies. The large impact of the status quo bias makes channeling consumers away from their current providers a daunting task, particularly in the case of GPs. © Health Research and Educational Trust.

Alternative Reinforcer Response Cost Impacts Cocaine Choice in Humans

PubMed Central

Stoops, William W.; Lile, Joshua A.; Glaser, Paul E.A.; Hays, Lon R.; Rush, Craig R.

2011-01-01

Cocaine use disorders are an unrelenting public health concern. Behavioral treatments reduce cocaine use by providing non-drug alternative reinforcers. The purpose of this human laboratory experiment was to determine how response cost for non-drug alternative reinforcers influenced cocaine choice. Seven cocaine-using, non-treatment-seeking subjects completed a crossover, double-blind protocol in which they first sampled doses of intranasal cocaine (5, 10, 20 or 30 mg) and completed a battery of subject-rated and physiological measures. Subjects then made eight discrete choices between the sampled dose and an alternative reinforce (US$0.25). The response cost to earn a cocaine dose was always a fixed ratio (FR) of 100 responses. The response cost for the alternative reinforcer varied across sessions (FR1, FR10, FR100, FR1000). Dose-related increases were observed for cocaine choice. Subjects made fewer drug choices when the FR requirements for the alternative reinforcers were lower than that for drug relative to when the FR requirements were equal to or higher than that for drug. Intranasal cocaine also produced prototypical stimulant-like subject-rated and physiological effects (e.g., increased ratings of Like Drug; elevated blood pressure). These data demonstrate that making alternative reinforcers easier to earn reduces cocaine self-administration, which has implications for treatment efforts. PMID:22015480

Dynamic Response-by-Response Models of Matching Behavior in Rhesus Monkeys

ERIC Educational Resources Information Center

Lau, Brian; Glimcher, Paul W.

2005-01-01

We studied the choice behavior of 2 monkeys in a discrete-trial task with reinforcement contingencies similar to those Herrnstein (1961) used when he described the matching law. In each session, the monkeys experienced blocks of discrete trials at different relative-reinforcer frequencies or magnitudes with unsignalled transitions between the…

Flexible Automatic Discretization for Finite Differences: Eliminating the Human Factor

NASA Astrophysics Data System (ADS)

Pranger, Casper

2017-04-01

In the geophysical numerical modelling community, finite differences are (in part due to their small footprint) a popular spatial discretization method for PDEs in the regular-shaped continuum that is the earth. However, they rapidly become prone to programming mistakes when physics increase in complexity. To eliminate opportunities for human error, we have designed an automatic discretization algorithm using Wolfram Mathematica, in which the user supplies symbolic PDEs, the number of spatial dimensions, and a choice of symbolic boundary conditions, and the script transforms this information into matrix- and right-hand-side rules ready for use in a C++ code that will accept them. The symbolic PDEs are further used to automatically develop and perform manufactured solution benchmarks, ensuring at all stages physical fidelity while providing pragmatic targets for numerical accuracy. We find that this procedure greatly accelerates code development and provides a great deal of flexibility in ones choice of physics.

Taste, choice and timing: Investigating resident and carer preferences for meals in aged care homes.

PubMed

Milte, Rachel; Ratcliffe, Julie; Chen, Gang; Miller, Michelle; Crotty, Maria

2018-03-01

There has been little empirical investigation of the preferences of people living in aged care homes for food services. The aim of the present study was to elicit consumer preferences and their willingness to pay for food service in aged care homes. Current residents or their family members were invited to take part in the discrete choice experiment questionnaire administered via interview. Of the 109 eligible residents and 175 eligible family members approached for consent 121 (43%) participated, including 43 residents. Participant preferences were influenced by food taste, choice in relation to serving size, timing of meal selection, visual appeal, and additional cost. Participants indicated they would be willing to pay an additional $24 (US$18.42) per week for food which tasted excellent and $8 (US$6.14) per week to have choice in serving sizes. The study found that respondents were willing to pay a premium to receive food that met their expectations of taste, and for a high level of control over serving sizes, which has implications for the funding and provision of food and dining in long-term care in the future. © 2018 The Authors Nursing & Health Sciences Published by John Wiley & Sons Australia, Ltd.

Alternative Reinforcer Response Cost Impacts Methamphetamine Choice in Humans

PubMed Central

Bennett, J. Adam; Stoops, William W.; Rush, Craig R.

2012-01-01

Methamphetamine use disorders are a persistent public health concern. Behavioral treatments have demonstrated that providing access to non-drug alternative reinforcers reduces methamphetamine use. The purpose of this human laboratory experiment was to determine how changes in response cost for non-drug alternative reinforcers influenced methamphetamine choice. Seven subjects with past year histories of recreational stimulant use completed a placebo-controlled, crossover, double-blind protocol in which they first sampled doses of oral methamphetamine (0, 8 or 16 mg) and completed a battery of subject-rated and physiological measures. During subsequent sessions, subjects then made eight discrete choices between 1/8th of the sampled dose and an alternative reinforcer ($0.25). The response cost to earn a methamphetamine dose was always 500 responses (FR500). The response cost for the alternative reinforcer varied across sessions (FR500, FR1000, FR2000, FR3000). Methamphetamine functioned as a positive reinforcer and produced prototypical stimulant-like effects (e.g., elevated blood pressure, increased ratings of “Stimulated”). Choice for doses over money was sensitive to changes in response cost for alternative reinforcers in that more doses were taken at higher FR values than at lower FR values. Placebo choices changed as a function of alternative reinforcer response cost to a greater degree than active methamphetamine choices. These findings suggest that manipulating the effort necessary to earn alternative reinforcers could impact methamphetamine use. PMID:23046851

A preference-ordered discrete-gaming approach to air-combat analysis

NASA Technical Reports Server (NTRS)

Kelley, H. J.; Lefton, L.

1978-01-01

An approach to one-on-one air-combat analysis is described which employs discrete gaming of a parameterized model featuring choice between several closed-loop control policies. A preference-ordering formulation due to Falco is applied to rational choice between outcomes: win, loss, mutual capture, purposeful disengagement, draw. Approximate optimization is provided by an active-cell scheme similar to Falco's obtained by a 'backing up' process similar to that of Kopp. The approach is designed primarily for short-duration duels between craft with large-envelope weaponry. Some illustrative computations are presented for an example modeled using constant-speed vehicles and very rough estimation of energy shifts.

An empirical comparison of methods for analyzing correlated data from a discrete choice survey to elicit patient preference for colorectal cancer screening

PubMed Central

2012-01-01

Background A discrete choice experiment (DCE) is a preference survey which asks participants to make a choice among product portfolios comparing the key product characteristics by performing several choice tasks. Analyzing DCE data needs to account for within-participant correlation because choices from the same participant are likely to be similar. In this study, we empirically compared some commonly-used statistical methods for analyzing DCE data while accounting for within-participant correlation based on a survey of patient preference for colorectal cancer (CRC) screening tests conducted in Hamilton, Ontario, Canada in 2002. Methods A two-stage DCE design was used to investigate the impact of six attributes on participants' preferences for CRC screening test and willingness to undertake the test. We compared six models for clustered binary outcomes (logistic and probit regressions using cluster-robust standard error (SE), random-effects and generalized estimating equation approaches) and three models for clustered nominal outcomes (multinomial logistic and probit regressions with cluster-robust SE and random-effects multinomial logistic model). We also fitted a bivariate probit model with cluster-robust SE treating the choices from two stages as two correlated binary outcomes. The rank of relative importance between attributes and the estimates of β coefficient within attributes were used to assess the model robustness. Results In total 468 participants with each completing 10 choices were analyzed. Similar results were reported for the rank of relative importance and β coefficients across models for stage-one data on evaluating participants' preferences for the test. The six attributes ranked from high to low as follows: cost, specificity, process, sensitivity, preparation and pain. However, the results differed across models for stage-two data on evaluating participants' willingness to undertake the tests. Little within-patient correlation (ICC ≈ 0) was found in stage-one data, but substantial within-patient correlation existed (ICC = 0.659) in stage-two data. Conclusions When small clustering effect presented in DCE data, results remained robust across statistical models. However, results varied when larger clustering effect presented. Therefore, it is important to assess the robustness of the estimates via sensitivity analysis using different models for analyzing clustered data from DCE studies. PMID:22348526

An explicit scheme for ohmic dissipation with smoothed particle magnetohydrodynamics

NASA Astrophysics Data System (ADS)

Tsukamoto, Yusuke; Iwasaki, Kazunari; Inutsuka, Shu-ichiro

2013-09-01

In this paper, we present an explicit scheme for Ohmic dissipation with smoothed particle magnetohydrodynamics (SPMHD). We propose an SPH discretization of Ohmic dissipation and solve Ohmic dissipation part of induction equation with the super-time-stepping method (STS) which allows us to take a longer time step than Courant-Friedrich-Levy stability condition. Our scheme is second-order accurate in space and first-order accurate in time. Our numerical experiments show that optimal choice of the parameters of STS for Ohmic dissipation of SPMHD is νsts ˜ 0.01 and Nsts ˜ 5.

Relations among Spontaneous Preferences, Familiarized Preferences, and Novelty Effects: Measurements with Forced-Choice Techniques

ERIC Educational Resources Information Center

Civan, Andrea; Teller, Davida Y.; Palmer, John

2005-01-01

We here describe a discrete trial, forced-choice, combined spontaneous preference and novelty preference technique. In this technique, spontaneous preferences and familiarized (postfamiliarization) preferences are measured with the same stimulus pairs under closely parallel conditions. A variety of systematic stimulus variations were used in…

A Cognitive Diagnosis Model for Cognitively Based Multiple-Choice Options

ERIC Educational Resources Information Center

de la Torre, Jimmy

2009-01-01

Cognitive or skills diagnosis models are discrete latent variable models developed specifically for the purpose of identifying the presence or absence of multiple fine-grained skills. However, applications of these models typically involve dichotomous or dichotomized data, including data from multiple-choice (MC) assessments that are scored as…

Managing coastal area resources by stated choice experiments

NASA Astrophysics Data System (ADS)

Liu, Xin; Wirtz, Kai W.

2010-02-01

In many coastal regions, oil spills can be considered as one of the most important and certainly the most noticeable forms of marine pollution. Efficient contingency management responding to oil spills on waters, which aims at minimizing pollution effects on coastal resources, turns out to be critically important. Such a decision making highly depends on the importance attributed to different coastal economic and ecological resources. Economic uses can, in principal, be addressed by standard measures such as value added. However, there is a missing of market in the real world for natural goods. Coastal resources such as waters and beach cannot be directly measured in money terms, which increases the risk of being neglected in a decision making process. This paper evaluates these natural goods of coastal environment in a hypothetical market by employing stated choice experiments. Oil spill management practice in German North Sea is used as an example. Results from a pilot survey show that during a combat process, beach and eider ducks are of key concerns for households. An environmental friendly combat option has to be a minor cost for households. Moreover, households with less children, higher monthly income and a membership of environmental organization are more likely to state that they are willing to pay for combat option to prevent coastal resources from an oil pollution. Despite that choice experiments require knowledge of designing questionnaire and statistical skills to deal with discrete choices and conducting a survey is time consumed, the results have important implications for oil spill contingency management. Overall, such a stated preference method can offer useful information for decision makers to consider coastal resources into a decision making process and can further contribute to finding a cost-effective oil preventive measure, also has a wide application potential in the field of Integrated Coastal Zone Management (ICZM).

Surveys suck: Consumer preferences when purchasing genetically engineered foods.

PubMed

Powell, Douglas A

2013-01-01

Many studies have attempted to gauge consumers' acceptance of genetically engineered or modified (GM) foods. Surveys, asking people about attitudes and intentions, are easy-to-collect proxies of consumer behavior. However, participants tend to respond as citizens of society, not discrete individuals, thereby inaccurately portraying their potential behavior. The Theory of Planned Behavior improved the accuracy of self-reported information, but its limited capacity to account for intention variance has been attributed to the hypothetical scenarios to which survey participants must respond. Valuation methods, asking how much consumers may be willing to pay or accept for GM foods, have revealed that consumers are usually willing to accept them at some price, or in some cases willing to pay a premium. Ultimately, it's consumers' actual--not intended--behavior that is of most interest to policy makers and business decision-makers. Real choice experiments offer the best avenue for revealing consumers' food choices in normal life.

Consumer Behavior in the Choice of Mode of Transport: A Case Study in the Toledo-Madrid Corridor

PubMed Central

Muro-Rodríguez, Ana I.; Perez-Jiménez, Israel R.; Gutiérrez-Broncano, Santiago

2017-01-01

Within the context of the consumption of goods or services the decisions made by individuals involve the choice between a set of discrete alternatives, such as the choice of mode of transport. The methodology for analyzing the consumer behavior are the models of discrete choice based on the Theory of Random Utility. These models are based on the definition of preferences through a utility function that is maximized. These models also denominated of disaggregated demand derived from the decision of a set of individuals, who are formalized by the application of probabilistic models. The objective of this study is to determine the behavior of the consumer in the choice of a service, namely of transport services and in a short-distance corridor, such as Toledo-Madrid. The Toledo-Madrid corridor is characterized by being short distance, with high speed train available within the choice options to get the airport, along with the bus and the car. And where offers of HST and aircraft services can be proposed as complementary modes. By applying disaggregated transport models with revealed preference survey data and declared preferences, one can determine the most important variables involved in the choice and determine the arrangements for payment of individuals. These payment provisions may condition the use of certain transport policies to promote the use of efficient transportation. PMID:28676776

Consumer Behavior in the Choice of Mode of Transport: A Case Study in the Toledo-Madrid Corridor.

PubMed

Muro-Rodríguez, Ana I; Perez-Jiménez, Israel R; Gutiérrez-Broncano, Santiago

2017-01-01

Within the context of the consumption of goods or services the decisions made by individuals involve the choice between a set of discrete alternatives, such as the choice of mode of transport. The methodology for analyzing the consumer behavior are the models of discrete choice based on the Theory of Random Utility. These models are based on the definition of preferences through a utility function that is maximized. These models also denominated of disaggregated demand derived from the decision of a set of individuals, who are formalized by the application of probabilistic models. The objective of this study is to determine the behavior of the consumer in the choice of a service, namely of transport services and in a short-distance corridor, such as Toledo-Madrid. The Toledo-Madrid corridor is characterized by being short distance, with high speed train available within the choice options to get the airport, along with the bus and the car. And where offers of HST and aircraft services can be proposed as complementary modes. By applying disaggregated transport models with revealed preference survey data and declared preferences, one can determine the most important variables involved in the choice and determine the arrangements for payment of individuals. These payment provisions may condition the use of certain transport policies to promote the use of efficient transportation.

Solution to the indexing problem of frequency domain simulation experiments

NASA Technical Reports Server (NTRS)

Mitra, Mousumi; Park, Stephen K.

1991-01-01

A frequency domain simulation experiment is one in which selected system parameters are oscillated sinusoidally to induce oscillations in one or more system statistics of interest. A spectral (Fourier) analysis of these induced oscillations is then performed. To perform this spectral analysis, all oscillation frequencies must be referenced to a common, independent variable - an oscillation index. In a discrete-event simulation, the global simulation clock is the most natural choice for the oscillation index. However, past efforts to reference all frequencies to the simulation clock generally yielded unsatisfactory results. The reason for these unsatisfactory results is explained in this paper and a new methodology which uses the simulation clock as the oscillation index is presented. Techniques for implementing this new methodology are demonstrated by performing a frequency domain simulation experiment for a network of queues.

Incorporating environmental attitudes in discrete choice models: an exploration of the utility of the awareness of consequences scale.

PubMed

Hoyos, David; Mariel, Petr; Hess, Stephane

2015-02-01

Environmental economists are increasingly interested in better understanding how people cognitively organise their beliefs and attitudes towards environmental change in order to identify key motives and barriers that stimulate or prevent action. In this paper, we explore the utility of a commonly used psychometric scale, the awareness of consequences (AC) scale, in order to better understand stated choices. The main contribution of the paper is that it provides a novel approach to incorporate attitudinal information into discrete choice models for environmental valuation: firstly, environmental attitudes are incorporated using a reinterpretation of the classical AC scale recently proposed by Ryan and Spash (2012); and, secondly, attitudinal data is incorporated as latent variables under a hybrid choice modelling framework. This novel approach is applied to data from a survey conducted in the Basque Country (Spain) in 2008 aimed at valuing land-use policies in a Natura 2000 Network site. The results are relevant to policy-making because choice models that are able to accommodate underlying environmental attitudes may help in designing more effective environmental policies. Copyright © 2014 Elsevier B.V. All rights reserved.

Phase computations and phase models for discrete molecular oscillators.

PubMed

Suvak, Onder; Demir, Alper

2012-06-11

Biochemical oscillators perform crucial functions in cells, e.g., they set up circadian clocks. The dynamical behavior of oscillators is best described and analyzed in terms of the scalar quantity, phase. A rigorous and useful definition for phase is based on the so-called isochrons of oscillators. Phase computation techniques for continuous oscillators that are based on isochrons have been used for characterizing the behavior of various types of oscillators under the influence of perturbations such as noise. In this article, we extend the applicability of these phase computation methods to biochemical oscillators as discrete molecular systems, upon the information obtained from a continuous-state approximation of such oscillators. In particular, we describe techniques for computing the instantaneous phase of discrete, molecular oscillators for stochastic simulation algorithm generated sample paths. We comment on the accuracies and derive certain measures for assessing the feasibilities of the proposed phase computation methods. Phase computation experiments on the sample paths of well-known biological oscillators validate our analyses. The impact of noise that arises from the discrete and random nature of the mechanisms that make up molecular oscillators can be characterized based on the phase computation techniques proposed in this article. The concept of isochrons is the natural choice upon which the phase notion of oscillators can be founded. The isochron-theoretic phase computation methods that we propose can be applied to discrete molecular oscillators of any dimension, provided that the oscillatory behavior observed in discrete-state does not vanish in a continuous-state approximation. Analysis of the full versatility of phase noise phenomena in molecular oscillators will be possible if a proper phase model theory is developed, without resorting to such approximations.

Phase computations and phase models for discrete molecular oscillators

PubMed Central

2012-01-01

Background Biochemical oscillators perform crucial functions in cells, e.g., they set up circadian clocks. The dynamical behavior of oscillators is best described and analyzed in terms of the scalar quantity, phase. A rigorous and useful definition for phase is based on the so-called isochrons of oscillators. Phase computation techniques for continuous oscillators that are based on isochrons have been used for characterizing the behavior of various types of oscillators under the influence of perturbations such as noise. Results In this article, we extend the applicability of these phase computation methods to biochemical oscillators as discrete molecular systems, upon the information obtained from a continuous-state approximation of such oscillators. In particular, we describe techniques for computing the instantaneous phase of discrete, molecular oscillators for stochastic simulation algorithm generated sample paths. We comment on the accuracies and derive certain measures for assessing the feasibilities of the proposed phase computation methods. Phase computation experiments on the sample paths of well-known biological oscillators validate our analyses. Conclusions The impact of noise that arises from the discrete and random nature of the mechanisms that make up molecular oscillators can be characterized based on the phase computation techniques proposed in this article. The concept of isochrons is the natural choice upon which the phase notion of oscillators can be founded. The isochron-theoretic phase computation methods that we propose can be applied to discrete molecular oscillators of any dimension, provided that the oscillatory behavior observed in discrete-state does not vanish in a continuous-state approximation. Analysis of the full versatility of phase noise phenomena in molecular oscillators will be possible if a proper phase model theory is developed, without resorting to such approximations. PMID:22687330

Affective and cognitive mechanisms of risky decision making.

PubMed

Shimp, Kristy G; Mitchell, Marci R; Beas, B Sofia; Bizon, Jennifer L; Setlow, Barry

2015-01-01

The ability to make advantageous decisions under circumstances in which there is a risk of adverse consequences is an important component of adaptive behavior; however, extremes in risk taking (either high or low) can be maladaptive and are characteristic of a number of neuropsychiatric disorders. To better understand the contributions of various affective and cognitive factors to risky decision making, cohorts of male Long-Evans rats were trained in a "Risky Decision making Task" (RDT), in which they made discrete trial choices between a small, "safe" food reward and a large, "risky" food reward accompanied by varying probabilities of footshock. Experiment 1 evaluated the relative contributions of the affective stimuli (i.e., punishment vs. reward) to RDT performance by parametrically varying the magnitudes of the footshock and large reward. Varying the shock magnitude had a significant impact on choice of the large, "risky" reward, such that greater magnitudes were associated with reduced choice of the large reward. In contrast, varying the large, "risky" reward magnitude had minimal influence on reward choice. Experiment 2 compared individual variability in RDT performance with performance in an attentional set shifting task (assessing cognitive flexibility), a delayed response task (assessing working memory), and a delay discounting task (assessing impulsive choice). Rats characterized as risk averse in the RDT made more perseverative errors on the set shifting task than did their risk taking counterparts, whereas RDT performance was not related to working memory abilities or impulsive choice. In addition, rats that showed greater delay discounting (greater impulsive choice) showed corresponding poorer performance in the working memory task. Together, these results suggest that reward-related decision making under risk of punishment is more strongly influenced by the punishment than by the reward, and that risky and impulsive decision making are associated with distinct components of executive function. Copyright © 2014 Elsevier Inc. All rights reserved.

Affective and cognitive mechanisms of risky decision making

PubMed Central

Shimp, Kristy G.; Mitchell, Marci R.; Beas, B. Sofia; Bizon, Jennifer L.; Setlow, Barry

2014-01-01

The ability to make advantageous decisions under circumstances in which there is a risk of adverse consequences is an important component of adaptive behavior; however, extremes in risk taking (either high or low) can be maladaptive and are characteristic of a number of neuropsychiatric disorders. To better understand the contributions of various affective and cognitive factors to risky decision making, cohorts of male Long-Evans rats were trained in a “Risky Decision making Task” (RDT), in which they made discrete trial choices between a small, “safe” food reward and a large, “risky” food reward accompanied by varying probabilities of footshock. Experiment 1 evaluated the relative contributions of the affective stimuli (i.e., punishment vs. reward) to RDT performance by parametrically varying the magnitudes of the footshock and large reward. Varying the shock magnitude had a significant impact on choice of the large, “risky” reward, such that greater magnitudes were associated with reduced choice of the large reward. In contrast, varying the large, “risky” reward magnitude had minimal influence on reward choice. Experiment 2 compared individual variability in RDT performance with performance in an attentional set shifting task (assessing cognitive flexibility), a delayed response task (assessing working memory), and a delay discounting task (assessing impulsive choice). Rats characterized as risk averse in the RDT made more perseverative errors on the set shifting task than did their risk taking counterparts, whereas RDT performance was not related to working memory abilities or impulsive choice. In addition, rats that showed greater delay discounting (greater impulsive choice) showed corresponding poorer performance in the working memory task. Together, these results suggest that reward-related decision making under risk of punishment is more strongly influenced by the punishment than by the reward, and that risky and impulsive decision making are associated with distinct components of executive function. PMID:24642448

Dual Formulations of Mixed Finite Element Methods with Applications

PubMed Central

Gillette, Andrew; Bajaj, Chandrajit

2011-01-01

Mixed finite element methods solve a PDE using two or more variables. The theory of Discrete Exterior Calculus explains why the degrees of freedom associated to the different variables should be stored on both primal and dual domain meshes with a discrete Hodge star used to transfer information between the meshes. We show through analysis and examples that the choice of discrete Hodge star is essential to the numerical stability of the method. Additionally, we define interpolation functions and discrete Hodge stars on dual meshes which can be used to create previously unconsidered mixed methods. Examples from magnetostatics and Darcy flow are examined in detail. PMID:21984841

Patient preferences for healthcare delivery through community pharmacy settings in the USA: A discrete choice study.

PubMed

Feehan, M; Walsh, M; Godin, J; Sundwall, D; Munger, M A

2017-12-01

In order to improve public health, it is necessary to facilitate patients' easy access to affordable high-quality primary health care, and one enhanced approach to do so may be to provide primary healthcare services in the community pharmacy setting. Discrete choice experiments to evaluate patient demand for services in pharmacy are relatively limited and have been hampered by a focus on only a few service alternatives, most focusing on changes in more traditional pharmacy services. The study aim was to gauge patient preferences explicitly for primary healthcare services that could be delivered through community pharmacy settings in the USA, using a very large sample to accommodate multiple service delivery options. An online survey was administered to a total of 9202 adult patients from the general population. A subsequent online survey was administered to 50 payer reimbursement decision-makers. The patient survey included a discrete choice experiment (DCE) which showed competing scenarios describing primary care service offerings. The respondents chose which scenario would be most likely to induce them to switch from their current pharmacy, and an optimal patient primary care service model was derived. The likelihood this model would be reimbursed was then determined in the payer survey. The final optimal service configuration that would maximize patient preference included the pharmacy: offering appointments to see a healthcare provider in the pharmacy, having access to their full medical record, provide point-of-care diagnostic testing, offer health preventive screening, provide limited physical examinations such as measuring vital signs, and drug prescribing in the pharmacy. The optimal model had the pharmacist as the provider; however, little change in demand was evident if the provider was a nurse-practitioner or physician's assistant. The demand for this optimal model was 2-fold higher (25.5%; 95% Bayesian precision interval (BPI) 23.5%-27.0%) than for a base pharmacy offering minimal primary care services (12.6%; 95% BPI 12.2%-13.2%), and was highest among Hispanic (30.6%; 95% BPI: 25.7%-34.3%) and African American patients (30.7%; 95% BPI: 27.1%-35.2%). In the second reimbursement decision-maker survey, the majority (66%) indicated their organization would be likely to reimburse the services described in the optimal patient model if provided in the pharmacy setting. This United States national study provides empirical support for a model of providing primary care services through community pharmacy settings that would increase access, with the potential to improve the public health. © 2017 John Wiley & Sons Ltd.

Australian Public Preferences for the Funding of New Health Technologies: A Comparison of Discrete Choice and Profile Case Best-Worst Scaling Methods.

PubMed

Whitty, Jennifer A; Ratcliffe, Julie; Chen, Gang; Scuffham, Paul A

2014-07-01

Ethical, economic, political, and legitimacy arguments support the consideration of public preferences in health technology decision making. The objective was to assess public preferences for funding new health technologies and to compare a profile case best-worst scaling (BWS) and traditional discrete choice experiment (DCE) method. An online survey consisting of a DCE and BWS task was completed by 930 adults recruited via an Internet panel. Respondents traded between 7 technology attributes. Participation quotas broadly reflected the population of Queensland, Australia, by gender and age. Choice data were analyzed using a generalized multinomial logit model. The findings from both the BWS and DCE were generally consistent in that respondents exhibited stronger preferences for technologies offering prevention or early diagnosis over other benefit types. Respondents also prioritized technologies that benefit younger people, larger numbers of people, those in rural areas, or indigenous Australians; that provide value for money; that have no available alternative; or that upgrade an existing technology. However, the relative preference weights and consequent preference orderings differed between the DCE and BWS models. Further, poor correlation between the DCE and BWS weights was observed. While only a minority of respondents reported difficulty completing either task (22.2% DCE, 31.9% BWS), the majority (72.6%) preferred the DCE over BWS task. This study provides reassurance that many criteria routinely used for technology decision making are considered to be relevant by the public. The findings clearly indicate the perceived importance of prevention and early diagnosis. The dissimilarity observed between DCE and profile case BWS weights is contrary to the findings of previous comparisons and raises uncertainty regarding the comparative merits of these stated preference methods in a priority-setting context. © The Author(s) 2014.

The Role of Qualitative Research Methods in Discrete Choice Experiments

PubMed Central

Vass, Caroline; Rigby, Dan; Payne, Katherine

2017-01-01

Background. The use of qualitative research (QR) methods is recommended as good practice in discrete choice experiments (DCEs). This study investigated the use and reporting of QR to inform the design and/or interpretation of healthcare-related DCEs and explored the perceived usefulness of such methods. Methods. DCEs were identified from a systematic search of the MEDLINE database. Studies were classified by the quantity of QR reported (none, basic, or extensive). Authors (n = 91) of papers reporting the use of QR were invited to complete an online survey eliciting their views about using the methods. Results. A total of 254 healthcare DCEs were included in the review; of these, 111 (44%) did not report using any qualitative methods; 114 (45%) reported “basic” information; and 29 (11%) reported or cited “extensive” use of qualitative methods. Studies reporting the use of qualitative methods used them to select attributes and/or levels (n = 95; 66%) and/or pilot the DCE survey (n = 26; 18%). Popular qualitative methods included focus groups (n = 63; 44%) and interviews (n = 109; 76%). Forty-four studies (31%) reported the analytical approach, with content (n = 10; 7%) and framework analysis (n = 5; 4%) most commonly reported. The survey identified that all responding authors (n = 50; 100%) found that qualitative methods added value to their DCE study, but many (n = 22; 44%) reported that journals were uninterested in the reporting of QR results. Conclusions. Despite recommendations that QR methods be used alongside DCEs, the use of QR methods is not consistently reported. The lack of reporting risks the inference that QR methods are of little use in DCE research, contradicting practitioners’ assessments. Explicit guidelines would enable more clarity and consistency in reporting, and journals should facilitate such reporting via online supplementary materials. PMID:28061040

The Role of Qualitative Research Methods in Discrete Choice Experiments.

PubMed

Vass, Caroline; Rigby, Dan; Payne, Katherine

2017-04-01

The use of qualitative research (QR) methods is recommended as good practice in discrete choice experiments (DCEs). This study investigated the use and reporting of QR to inform the design and/or interpretation of healthcare-related DCEs and explored the perceived usefulness of such methods. DCEs were identified from a systematic search of the MEDLINE database. Studies were classified by the quantity of QR reported (none, basic, or extensive). Authors ( n = 91) of papers reporting the use of QR were invited to complete an online survey eliciting their views about using the methods. A total of 254 healthcare DCEs were included in the review; of these, 111 (44%) did not report using any qualitative methods; 114 (45%) reported "basic" information; and 29 (11%) reported or cited "extensive" use of qualitative methods. Studies reporting the use of qualitative methods used them to select attributes and/or levels ( n = 95; 66%) and/or pilot the DCE survey ( n = 26; 18%). Popular qualitative methods included focus groups ( n = 63; 44%) and interviews ( n = 109; 76%). Forty-four studies (31%) reported the analytical approach, with content ( n = 10; 7%) and framework analysis ( n = 5; 4%) most commonly reported. The survey identified that all responding authors ( n = 50; 100%) found that qualitative methods added value to their DCE study, but many ( n = 22; 44%) reported that journals were uninterested in the reporting of QR results. Despite recommendations that QR methods be used alongside DCEs, the use of QR methods is not consistently reported. The lack of reporting risks the inference that QR methods are of little use in DCE research, contradicting practitioners' assessments. Explicit guidelines would enable more clarity and consistency in reporting, and journals should facilitate such reporting via online supplementary materials.

Valuing Health Using Time Trade-Off and Discrete Choice Experiment Methods: Does Dimension Order Impact on Health State Values?

PubMed

Mulhern, Brendan; Shah, Koonal; Janssen, Mathieu F Bas; Longworth, Louise; Ibbotson, Rachel

2016-01-01

Health states defined by multiattribute instruments such as the EuroQol five-dimensional questionnaire with five response levels (EQ-5D-5L) can be valued using time trade-off (TTO) or discrete choice experiment (DCE) methods. A key feature of the tasks is the order in which the health state dimensions are presented. Respondents may use various heuristics to complete the tasks, and therefore the order of the dimensions may impact on the importance assigned to particular states. To assess the impact of different EQ-5D-5L dimension orders on health state values. Preferences for EQ-5D-5L health states were elicited from a broadly representative sample of members of the UK general public. Respondents valued EQ-5D-5L health states using TTO and DCE methods across one of three dimension orderings via face-to-face computer-assisted personal interviews. Differences in mean values and the size of the health dimension coefficients across the arms were compared using difference testing and regression analyses. Descriptive analysis suggested some differences between the mean TTO health state values across the different dimension orderings, but these were not systematic. Regression analysis suggested that the magnitude of the dimension coefficients differs across the different dimension orderings (for both TTO and DCE), but there was no clear pattern. There is some evidence that the order in which the dimensions are presented impacts on the coefficients, which may impact on the health state values provided. The order of dimensions is a key consideration in the design of health state valuation studies. Copyright © 2016. Published by Elsevier Inc.

Acceptability of Financial Incentives for Health Behaviours: A Discrete Choice Experiment.

PubMed

Giles, Emma L; Becker, Frauke; Ternent, Laura; Sniehotta, Falko F; McColl, Elaine; Adams, Jean

2016-01-01

Healthy behaviours are important determinants of health and disease, but many people find it difficult to perform these behaviours. Systematic reviews support the use of personal financial incentives to encourage healthy behaviours. There is concern that financial incentives may be unacceptable to the public, those delivering services and policymakers, but this has been poorly studied. Without widespread acceptability, financial incentives are unlikely to be widely implemented. We sought to answer two questions: what are the relative preferences of UK adults for attributes of financial incentives for healthy behaviours? Do preferences vary according to the respondents' socio-demographic characteristics? We conducted an online discrete choice experiment. Participants were adult members of a market research panel living in the UK selected using quota sampling. Preferences were examined for financial incentives for: smoking cessation, regular physical activity, attendance for vaccination, and attendance for screening. Attributes of interest (and their levels) were: type of incentive (none, cash, shopping vouchers or lottery tickets); value of incentive (a continuous variable); schedule of incentive (same value each week, or value increases as behaviour change is sustained); other information provided (none, written information, face-to-face discussion, or both); and recipients (all eligible individuals, people living in low-income households, or pregnant women). Cash or shopping voucher incentives were preferred as much as, or more than, no incentive in all cases. Lower value incentives and those offered to all eligible individuals were preferred. Preferences for additional information provided alongside incentives varied between behaviours. Younger participants and men were more likely to prefer incentives. There were no clear differences in preference according to educational attainment. Cash or shopping voucher-type financial incentives for healthy behaviours are not necessarily less acceptable than no incentives to UK adults.

The impact of vaccination and patient characteristics on influenza vaccination uptake of elderly people: A discrete choice experiment.

PubMed

de Bekker-Grob, Esther W; Veldwijk, Jorien; Jonker, Marcel; Donkers, Bas; Huisman, Jan; Buis, Sylvia; Swait, Joffre; Lancsar, Emily; Witteman, Cilia L M; Bonsel, Gouke; Bindels, Patrick

2018-03-07

To improve information for patients and to facilitate a vaccination coverage that is in line with the EU and World Health Organization goals, we aimed to quantify how vaccination and patient characteristics impact on influenza vaccination uptake of elderly people. An online discrete choice experiment (DCE) was conducted among 1261 representatives of the Dutch general population aged 60 years or older. In the DCE, we used influenza vaccination scenarios based on five vaccination characteristics: effectiveness, risk of severe side effects, risk of mild side effects, protection duration, and absorption time. A heteroscedastic multinomial logit model was used, taking scale and preference heterogeneity (based on 19 patient characteristics) into account. Vaccination and patient characteristics both contributed to explain influenza vaccination uptake. Assuming a base case respondent and a realistic vaccination scenario, the predicted uptake was 58%. One-way changes in vaccination characteristics and patient characteristics changed this uptake from 46% up to 61% and from 37% up to 95%, respectively. The strongest impact on vaccination uptake was whether the patient had been vaccinated last year, whether s/he had experienced vaccination side effects, and the patient's general attitude towards vaccination. Although vaccination characteristics proved to influence influenza vaccination uptake, certain patient characteristics had an even higher impact on influenza vaccination uptake. Policy makers and general practitioners can use these insights to improve their communication plans and information regarding influenza vaccination for individuals aged 60 years or older. For instance, physicians should focus more on patients who had experienced side effects due to vaccination in the past, and policy makers should tailor the standard information folder to patients who had been vaccinated last year and to patient who had not. Copyright © 2018 Elsevier Ltd. All rights reserved.

Women's preferences and mode of delivery in public and private hospitals: a prospective cohort study.

PubMed

Mazzoni, Agustina; Althabe, Fernando; Gutierrez, Laura; Gibbons, Luz; Liu, Nancy H; Bonotti, Ana María; Izbizky, Gustavo H; Ferrary, Marta; Viergue, Nora; Vigil, Silvia I; Zalazar Denett, Gabriela; Belizán, José M

2016-02-08

Rates of caesarean section have steadily increased in most middle- and high-income countries over the last few decades without medical justification. Maternal request is one of the frequently cited non-medical factors contributing to this trend. The objectives of this study were to assess pregnant women's preferences regarding mode of delivery and to compare actual caesarean section rates in the public and private sectors. A prospective cohort study was conducted in two public and three private hospitals in Buenos Aires, Argentina. 382 nulliparous pregnant women (183 from the private sector and 199 from the public sector) aged 18 to 35 years, with single pregnancies over 32 weeks of gestational age were enrolled during antenatal care visits between October 2010 and September 2011. We excluded women with pregnancies resulting from assisted fertility, women with known pre-existing major diseases or, with pregnancy complications, or with a medical indication of elective cesarean section. We used two different approaches to assess women's preferences: a survey using a tailored questionnaire, and a discrete choice experiment. Only 8 and 6% of the healthy nulliparous women in the public and private sectors, respectively, expressed a preference for caesarean section. Fear of pain and safety were the most frequently expressed reasons for preferring caesarean section. When reasons for delivery mode were assessed by a discrete choice experiment, women placed the most emphasis on sex after childbirth. Of women who expressed their preference for vaginal delivery, 34 and 40% ended their pregnancies by caesarean section in public and private hospitals, respectively. The preference for caesarean section is low among healthy nulliparous women in Buenos Aires. The reasons why these women had a rate of more than 35% caesarean sections are unlikely related to their preferences for mode of delivery.

Job preferences among clinical officers in public sector facilities in rural Kenya: a discrete choice experiment.

PubMed

Takemura, Toshio; Kielmann, Karina; Blaauw, Duane

2016-01-08

Clinical officers (COs), a mid-level cadre of health worker, are the backbone of healthcare provision in rural Kenya. However, the vacancy rate for COs in rural primary healthcare facilities is high. Little is known about factors motivating COs' preferences for rural postings. A discrete choice experiment (DCE) questionnaire was used with 57 COs at public health facilities in nine districts of Nyanza Province, Kenya. The questionnaire was developed on the basis of formative qualitative interviews with COs (n = 5) and examined how five selected job attributes influenced COs' preferences for working in rural areas. Conditional logit models were employed to examine the relative importance of different job attributes. Analysis of the qualitative data revealed five important job attributes influencing COs' preferences: quality of the facility, educational opportunities, housing, monthly salary and promotion. Analysis of the DCE indicated that a 1-year guaranteed study leave after 3 years of service would have the greatest impact on retention, followed by good quality health facility infrastructure and equipment and a 30% salary increase. Sub-group analysis shows that younger COs demonstrated a significantly stronger preference for study leave than older COs. Female COs placed significantly higher value on promotion than male COs. Although both financial incentives and non-financial incentives were effective in motivating COs to stay in post, the study leave intervention was shown to have the strongest impact on COs' retention in our study. Further research is required to examine appropriate interventions at each career stage that might boost COs' professional identity and status but without leading to larger deficits in the availability of generalist COs.

Public preferences for interventions to prevent emerging infectious disease threats: a discrete choice experiment.

PubMed

Cook, Alex R; Zhao, Xiahong; Chen, Mark I C; Finkelstein, Eric A

2018-02-16

When faced with an emergent epidemic with high mortality and morbidity potential, policy makers must decide what public health interventions to deploy at different stages of the outbreak. However, almost nothing is known about how the public view these interventions or how they trade off risks (of disease) with inconvenience (of interventions). In this paper, we aim to understand public perceptions on pandemic interventions, as well as to identify if there are any distinct respondent preference classes. A discrete choice experiment. This study was fielded in Singapore between November 2012 and February 2013. A random sample of 500 Singapore residents aged 21 and over, including 271 women and 229 men, was analysed. Demographic information was collected from each participant. Participants were also shown a series of pairs of alternatives, each combining interventions and morbidity, mortality and cost outcomes and declared a preference for one combination. A random utility model was developed to determine the individual's preference for interventions and a hierarchical cluster analysis was performed to identify distinct respondent preference classes. On average, participants preferred more intense interventions, and preferred scenarios with fewer deaths and lower tax. The number of infections did not significantly influence respondents' responses. We identified two broad classes of respondents: those who were mortality averse and those who were expenditure averse. Education was found to be a predictor of group membership. Overall, there was considerable support for government interventions to prevent or mitigate outbreaks of emerging infectious diseases, including those that greatly restricted individual liberties, as long as the restrictions showed a reasonable chance of reducing the adverse health effects of the outbreak. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Patient and nurse preferences for nurse handover—using preferences to inform policy: a discrete choice experiment protocol

PubMed Central

Spinks, Jean; Chaboyer, Wendy; Bucknall, Tracey; Tobiano, Georgia; Whitty, Jennifer A

2015-01-01

Introduction Nursing bedside handover in hospital has been identified as an opportunity to involve patients and promote patient-centred care. It is important to consider the preferences of both patients and nurses when implementing bedside handover to maximise the successful uptake of this policy. We outline a study which aims to (1) identify, compare and contrast the preferences for various aspects of handover common to nurses and patients while accounting for other factors, such as the time constraints of nurses that may influence these preferences.; (2) identify opportunities for nurses to better involve patients in bedside handover and (3) identify patient and nurse preferences that may challenge the full implementation of bedside handover in the acute medical setting. Methods and analysis We outline the protocol for a discrete choice experiment (DCE) which uses a survey design common to both patients and nurses. We describe the qualitative and pilot work undertaken to design the DCE. We use a D-efficient design which is informed by prior coefficients collected during the pilot phase. We also discuss the face-to-face administration of this survey in a population of acutely unwell, hospitalised patients and describe how data collection challenges have been informed by our pilot phase. Mixed multinomial logit regression analysis will be used to estimate the final results. Ethics and dissemination This study has been approved by a university ethics committee as well as two participating hospital ethics committees. Results will be used within a knowledge translation framework to inform any strategies that can be used by nursing staff to improve the uptake of bedside handover. Results will also be disseminated via peer-reviewed journal articles and will be presented at national and international conferences. PMID:26560060

Application of discrete choice experiment to assess farmers' willingness to report swine diseases in the Red River Delta region, Vietnam.

PubMed

Pham, Hoa T T; Peyre, Marisa; Trinh, Tuyen Quang; Nguyen, Oanh Cong; Vu, Ton Dinh; Rukkwamsuk, Theera; Antoine-Moussiaux, Nicolas

2017-03-01

A discrete choice experiment (DCE) is carried out to value socio-economic factors influencing the farmer's decision to report swine diseases and to assess the willingness of farmers to report swine diseases. Data were collected between March and July 2015 in two provinces in the Red River Delta, Northern Vietnam, from 196 pig producers by face-to face interview. A conditional logit model is used to measure the relative importance of the socio-economic factors and calculate the expected probability of disease reporting under changes of levels of these factors. Results of the study indicated that the likelihood of compensation and the type of culling implemented (all or only unrecovered pigs) are the two most important factors influencing farmer reporting. Compensation level, movement restriction and delay in compensation payment also have significant impacts on farmer's decision to report animal disease but they are not as important as the above factors. Three different scenarios including changes in six different factors (attributes) are tested to predict probability of animal disease reporting. Under the current situation (uncertainty of being compensated), only 4% of the farmers would report swine disease outbreak to the official surveillance system if the culling policy involves all pigs in affected farms. This number is increased to 26% if culling in affected farms is restricted to unrecovered pigs only. Ensuring certainty of compensation increases reporting probability by up to 50% and 90% if all or only unrecovered pigs are destroyed, respectively. The results of this study are important for improving the performance and sustainability of swine disease surveillance system in Vietnam. Copyright © 2017 Elsevier B.V. All rights reserved.

Mothers' Preferences and Willingness to Pay for Human Papillomavirus Vaccination for Their Daughters: A Discrete Choice Experiment in Hong Kong.

PubMed

Wong, Carlos K H; Man, Kenneth K C; Ip, Patrick; Kwan, Mike; McGhee, Sarah M

2018-05-01

To determine the preference of mothers in Hong Kong and their willingness to pay (WTP) for human papillomavirus (HPV) vaccination for their daughters. A discrete choice experiment survey with a two-alternative study design was developed. Data were collected from pediatric specialist outpatient clinics from 482 mothers with daughters aged between 8 and 17 years. Preferences of the four attributes of HPV vaccines (protection against cervical cancer, protection duration, side effects, and out-of-pocket costs) were evaluated. The marginal and overall WTP were estimated using multinomial logistic regression. A subgroup analysis was conducted to explore the impact of socioeconomic factors on mothers' WTP. Side effects, protection against cervical cancer, protection duration, and out-of-pocket cost determined the decision to receive or not receive the vaccine. All attributes had a statistically significant effect on the preference of and the WTP for the vaccine. Maximum WTP for ideal vaccines (i.e., 100% protection, lifetime protection duration, and 0% side effects) was HK$8976 (US $1129). The estimated WTP for vaccines currently available was HK$1620 (US $208), lower than the current market price. Among those who had a monthly household income of more than HK$100,000 (US $12,821), the WTP for vaccines currently offered was higher than the market price. This study provides new data on how features of the HPV vaccine are viewed and valued by mothers by determining their perception of ideal or improved and current vaccine technologies. These findings could contribute to future policies on the improvement of HPV vaccine and be useful for the immunization service in Hong Kong. Copyright © 2017 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Providing Informal Care in Terminal Illness: An Analysis of Preferences for Support Using a Discrete Choice Experiment.

PubMed

Hall, Jane; Kenny, Patricia; Hossain, Ishrat; Street, Deborah J; Knox, Stephanie A

2014-08-01

The trend for terminally ill patients to receive much of their end-of-life care at home necessitates the design of services to facilitate this. Care at home also requires that informal care be provided by family members and friends. This study investigated informal carers' preferences for support services to aid the development of end-of-life health care services. This cross-sectional study used 2 discrete choice experiments to ascertain the preferences of carers supporting patients with different levels of care need, determined by the assistance needed with personal care and labeled High Care (HC) and Low Care (LC). The sample included 168 informal carers of people receiving palliative care at home from 2 palliative care services in Sydney, Australia. Data were collected in face-to-face interviews; carers chose between 2 hypothetical plans of support services and their current services. Data were analyzed with generalized multinomial logit models that were used to calculate the impact of each attribute on the probability of a carer choosing a service plan. Preferred support included nursing services; the probability of choosing a plan increased significantly if it included nurse home visits and phone advice (P < 0.001). HC carers also wanted doctor home visits, home respite, and help with personal care (P < 0.05), and LC carers wanted help with household tasks, transport, and a case coordinator (P < 0.001). On average, both groups of carers preferred their current services, but this varied with characteristics of the carer and the caregiving situation. The most valued services are those that support carers in their caregiving role; however, supportive care preferences vary with the different circumstances of patients and carers. © The Author(s) 2013.

Valuations of genetic test information for treatable conditions: the case of colorectal cancer screening.

PubMed

Kilambi, Vikram; Johnson, F Reed; González, Juan Marcos; Mohamed, Ateesha F

2014-12-01

The value of the information that genetic testing services provide can be questioned for insurance-based health systems. The results of genetic tests oftentimes may not lead to well-defined clinical interventions; however, Lynch syndrome, a genetic mutation for which carriers are at an increased risk for colorectal cancer, can be identified through genetic testing, and meaningful health interventions are available via increased colonoscopic surveillance. Valuations of test information for such conditions ought to account for the full impact of interventions and contingent outcomes. To conduct a discrete-choice experiment to elicit individuals' preferences for genetic test information. A Web-enabled discrete-choice experiment survey was administered to a representative sample of US residents aged 50 years and older. In addition to specifying expenditures on colonoscopies, respondents were asked to make a series of nine selections between two hypothetical genetic tests or a no-test option under the premise that a relative had Lynch syndrome. The hypothetical genetic tests were defined by the probability of developing colorectal cancer, the probability of a false-negative test result, privacy of the result, and out-of-pocket cost. A model specification identifying necessary interactions was derived from assumptions of risk behavior and the decision context and was estimated using random-parameters logit. A total of 650 respondents were contacted, and 385 completed the survey. The monetary equivalent of test information was approximately $1800. Expenditures on colonoscopies to reduce mortality risks affected valuations. Respondents with lower income or who reported being employed significantly valued genetic tests more. Genetic testing may confer benefits through the impact of subsequent interventions on private individuals. Copyright © 2014. Published by Elsevier Inc.

A novel design process for selection of attributes for inclusion in discrete choice experiments: case study exploring variation in clinical decision-making about thrombolysis in the treatment of acute ischaemic stroke.

PubMed

De Brún, Aoife; Flynn, Darren; Ternent, Laura; Price, Christopher I; Rodgers, Helen; Ford, Gary A; Rudd, Matthew; Lancsar, Emily; Simpson, Stephen; Teah, John; Thomson, Richard G

2018-06-22

A discrete choice experiment (DCE) is a method used to elicit participants' preferences and the relative importance of different attributes and levels within a decision-making process. DCEs have become popular in healthcare; however, approaches to identify the attributes/levels influencing a decision of interest and to selection methods for their inclusion in a DCE are under-reported. Our objectives were: to explore the development process used to select/present attributes/levels from the identified range that may be influential; to describe a systematic and rigorous development process for design of a DCE in the context of thrombolytic therapy for acute stroke; and, to discuss the advantages of our five-stage approach to enhance current guidance for developing DCEs. A five-stage DCE development process was undertaken. Methods employed included literature review, qualitative analysis of interview and ethnographic data, expert panel discussions, a quantitative structured prioritisation (ranking) exercise and pilot testing of the DCE using a 'think aloud' approach. The five-stage process reported helped to reduce the list of 22 initial patient-related factors to a final set of nine variable factors and six fixed factors for inclusion in a testable DCE using a vignette model of presentation. In order for the data and conclusions generated by DCEs to be deemed valid, it is crucial that the methods of design and development are documented and reported. This paper has detailed a rigorous and systematic approach to DCE development which may be useful to researchers seeking to establish methods for reducing and prioritising attributes for inclusion in future DCEs.

Factors that influence midwifery students in Ghana when deciding where to practice: a discrete choice experiment.

PubMed

Ageyi-Baffour, Peter; Rominski, Sarah; Nakua, Emmanuel; Gyakobo, Mawuli; Lori, Jody R

2013-05-04

Mal-distribution of the health workforce with a strong bias for urban living is a major constraint to expanding midwifery services in Ghana. According to the UN Millennium Development Goals (MDG) report, the high risk of dying in pregnancy or childbirth continues in Africa. Maternal death is currently estimated at 350 per 100,000, partially a reflection of the low rates of professional support during birth. Many women in rural areas of Ghana give birth alone or with a non-skilled attendant. Midwives are key healthcare providers in achieving the MDGs, specifically in reducing maternal mortality by three-quarters and reducing by two-thirds the under 5 child mortality rate by 2015. This quantitative research study used a computerized structured survey containing a discrete choice experiment (DCE) to quantify the importance of different incentives and policies to encourage service to deprived, rural and remote areas by upper-year midwifery students following graduation. Using a hierarchical Bayes procedure we estimated individual and mean utility parameters for two hundred and ninety eight third year midwifery students from two of the largest midwifery training schools in Ghana. Midwifery students in our sample identified: 1) study leave after two years of rural service; 2) an advanced work environment with reliable electricity, appropriate technology and a constant drug supply; and 3) superior housing (2 bedroom, 1 bathroom, kitchen, living room, not shared) as the top three motivating factors to accept a rural posting. Addressing the motivating factors for rural postings among midwifery students who are about to graduate and enter the workforce could significantly contribute to the current mal-distribution of the health workforce.

Understanding HIV-positive patients' preferences for healthcare services: a protocol for a discrete choice experiment.

PubMed

Youssef, Elaney; Cooper, Vanessa; Miners, Alec; Llewellyn, Carrie; Pollard, Alex; Lagarde, Mylene; Sachikonye, Memory; Sabin, Caroline; Foreman, Claire; Perry, Nicky; Nixon, Eileen; Fisher, Martin

2016-07-18

While the care of HIV-positive patients, including the detection and management of comorbidities, has historically been provided in HIV specialist outpatient clinics, recent years have seen a greater involvement of non-HIV specialists and general practitioners (GPs). The aim of this study is to determine whether patients would prefer to see their GP or HIV physician given general symptoms, and to understand what aspects of care influence their preferences. We have developed and piloted a discrete choice experiment (DCE) to better understand patients' preferences for care of non-HIV-related acute symptoms. The design of the DCE was informed by our exploratory research, including the findings of a systematic literature review and a qualitative study. Additional questionnaire items have been included to measure demographics, service use and experience of non-HIV illnesses and quality of life (EQ5D). We plan to recruit 1000 patients from 14 HIV clinics across South East England. Data will be analysed using random-effects logistic regression and latent class analysis. ORs and 95% CIs will be used to estimate the relative importance of each of the attribute levels. Latent class analysis will identify whether particular groups of people value the service attribute levels differently. Ethical approval for this study was obtained from the Newcastle and North Tyneside Research Ethics Committee (reference number 14/NE/1193). The results will be disseminated at national and international conferences and peer-reviewed publications. A study report, written in plain English, will be made available to all participants. The Patient Advisory Group will develop a strategy for wider dissemination of the findings to patients and the public. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

"It can be challenging, it can be scary, it can be gratifying": Obstetricians' narratives of negotiating patient choice, clinical experience, and standards of care in decision-making.

PubMed

Diamond-Brown, Lauren

2018-05-01

This paper examines obstetricians' perceptions of standards of care and patient-centered care in clinical decision-making in childbirth. Patient-centered care and standardization of medicine are two social movements that seek to change how physicians make clinical decisions. Sociologists question if these limit physician discretion and weaken their social power; the degree to which this occurs in everyday practice is up for debate. Of additional concern is how physicians deal with observed tensions between these ideals. These questions are answered through in-depth interviews with 50 self-selected obstetricians from Massachusetts, Louisiana, and Vermont collected between 2013 and 2015. Interview data was analyzed using a grounded theory and template approach. The author problematizes obstetricians' attitudes about standards of care and shared decision-making, mechanisms that encourage or discourage these approaches to decision-making, and how obstetricians negotiate tensions between patient choice, clinical experience, and standards. The key findings are that most obstetricians feel they have the authority to interpret the appropriateness of standards and patient choice on a case-by-case basis. They feel empowered and/or constrained by pressures to practice patient-centered care and standards depending upon their style of practice and the organizational context. Following standards of care is encouraged through organizational mechanisms such as pressure from colleagues, malpractice threat, hospital policy, and payer restrictions. Practicing shared decision-making is challenged when the patient wants something that violates the physician's clinical experience and/or standards of care. When obstetricians prioritize patient choice over experience and/or standards this is done for moral reasons, less so because of organizational pressures. These findings have implications for theorizing the social status of medical professionals, understanding how physicians deal with tensions between standardized and individualized ideals in medicine, and illuminating the way obstetricians interpret power in the physician-patient relationship. Copyright © 2018 Elsevier Ltd. All rights reserved.

A curvilinear, fully implicit, conservative electromagnetic PIC algorithm in multiple dimensions

DOE PAGES

Chacon, L.; Chen, G.

2016-04-19

Here, we extend a recently proposed fully implicit PIC algorithm for the Vlasov–Darwin model in multiple dimensions (Chen and Chacón (2015) [1]) to curvilinear geometry. As in the Cartesian case, the approach is based on a potential formulation (Φ, A), and overcomes many difficulties of traditional semi-implicit Darwin PIC algorithms. Conservation theorems for local charge and global energy are derived in curvilinear representation, and then enforced discretely by a careful choice of the discretization of field and particle equations. Additionally, the algorithm conserves canonical-momentum in any ignorable direction, and preserves the Coulomb gauge ∇ • A = 0 exactly. Anmore » asymptotically well-posed fluid preconditioner allows efficient use of large cell sizes, which are determined by accuracy considerations, not stability, and can be orders of magnitude larger than required in a standard explicit electromagnetic PIC simulation. We demonstrate the accuracy and efficiency properties of the algorithm with numerical experiments in mapped meshes in 1D-3V and 2D-3V.« less

A curvilinear, fully implicit, conservative electromagnetic PIC algorithm in multiple dimensions

NASA Astrophysics Data System (ADS)

Chacón, L.; Chen, G.

2016-07-01

We extend a recently proposed fully implicit PIC algorithm for the Vlasov-Darwin model in multiple dimensions (Chen and Chacón (2015) [1]) to curvilinear geometry. As in the Cartesian case, the approach is based on a potential formulation (ϕ, A), and overcomes many difficulties of traditional semi-implicit Darwin PIC algorithms. Conservation theorems for local charge and global energy are derived in curvilinear representation, and then enforced discretely by a careful choice of the discretization of field and particle equations. Additionally, the algorithm conserves canonical-momentum in any ignorable direction, and preserves the Coulomb gauge ∇ ṡ A = 0 exactly. An asymptotically well-posed fluid preconditioner allows efficient use of large cell sizes, which are determined by accuracy considerations, not stability, and can be orders of magnitude larger than required in a standard explicit electromagnetic PIC simulation. We demonstrate the accuracy and efficiency properties of the algorithm with numerical experiments in mapped meshes in 1D-3V and 2D-3V.

A curvilinear, fully implicit, conservative electromagnetic PIC algorithm in multiple dimensions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chacon, L.; Chen, G.

Here, we extend a recently proposed fully implicit PIC algorithm for the Vlasov–Darwin model in multiple dimensions (Chen and Chacón (2015) [1]) to curvilinear geometry. As in the Cartesian case, the approach is based on a potential formulation (Φ, A), and overcomes many difficulties of traditional semi-implicit Darwin PIC algorithms. Conservation theorems for local charge and global energy are derived in curvilinear representation, and then enforced discretely by a careful choice of the discretization of field and particle equations. Additionally, the algorithm conserves canonical-momentum in any ignorable direction, and preserves the Coulomb gauge ∇ • A = 0 exactly. Anmore » asymptotically well-posed fluid preconditioner allows efficient use of large cell sizes, which are determined by accuracy considerations, not stability, and can be orders of magnitude larger than required in a standard explicit electromagnetic PIC simulation. We demonstrate the accuracy and efficiency properties of the algorithm with numerical experiments in mapped meshes in 1D-3V and 2D-3V.« less

Supporting driver headway choice: the effects of discrete headway feedback when following headway instructions.

PubMed

Risto, Malte; Martens, Marieke H

2014-07-01

With specific headway instructions drivers are not able to attain the exact headways as instructed. In this study, the effects of discrete headway feedback (and the direction of headway adjustment) on headway accuracy for drivers carrying out time headway instructions were assessed experimentally. Two groups of each 10 participants (one receiving headway feedback; one control) carried out headway instructions in a driving simulator; increasing and decreasing their headway to a target headway of 2 s at speeds of 50, 80, and 100 km/h. The difference between the instructed and chosen headway was a measure for headway accuracy. The feedback group heard a sound signal at the moment that they crossed the distance of the instructed headway. Unsupported participants showed no significant difference in headway accuracy when increasing or decreasing headways. Discrete headway feedback had varying effects on headway choice accuracy. When participants decreased their headway, feedback led to higher accuracy. When increasing their headway, feedback led to a lower accuracy, compared to no headway feedback. Support did not affect driver's performance in maintaining the chosen headway. The present results suggest that (a) in its current form discrete headway feedback is not sufficient to improve the overall accuracy of chosen headways when carrying out headway instructions; (b) the effect of discrete headway feedback depends on the direction of headway adjustment. Copyright © 2014 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Incompressible Navier-Stokes and parabolized Navier-Stokes solution procedures and computational techniques

NASA Technical Reports Server (NTRS)

Rubin, S. G.

1982-01-01

Recent developments with finite-difference techniques are emphasized. The quotation marks reflect the fact that any finite discretization procedure can be included in this category. Many so-called finite element collocation and galerkin methods can be reproduced by appropriate forms of the differential equations and discretization formulas. Many of the difficulties encountered in early Navier-Stokes calculations were inherent not only in the choice of the different equations (accuracy), but also in the method of solution or choice of algorithm (convergence and stability, in the manner in which the dependent variables or discretized equations are related (coupling), in the manner that boundary conditions are applied, in the manner that the coordinate mesh is specified (grid generation), and finally, in recognizing that for many high Reynolds number flows not all contributions to the Navier-Stokes equations are necessarily of equal importance (parabolization, preferred direction, pressure interaction, asymptotic and mathematical character). It is these elements that are reviewed. Several Navier-Stokes and parabolized Navier-Stokes formulations are also presented.

Decision-makers' preferences for approving new medicines in Wales: a discrete-choice experiment with assessment of external validity.

PubMed

Linley, Warren G; Hughes, Dyfrig A

2013-04-01

Few studies to date have explored the stated preferences of national decision makers for health technology adoption criteria, and none of these have compared stated decision-making behaviours against actual behaviours. Assessment of the external validity of stated preference studies, such as discrete-choice experiments (DCEs), remains an under-researched area. The primary aim was to explore the preferences of All Wales Medicines Strategy Group (AWMSG) appraisal committee and appraisal sub-committee (the New Medicines Group) members ('appraisal committees') for specific new medicines adoption criteria. Secondary aims were to explore the external validity of respondents' stated preferences and the impact of question choice options upon preference structures in DCEs. A DCE was conducted to estimate appraisal committees members' preferences for incremental cost effectiveness, quality-adjusted life-years (QALYs) gained, annual number of patients expected to be treated, the impact of the disease on patients before treatment, and the assessment of uncertainty in the economic evidence submitted for new medicines compared with current UK NHS treatment. Respondents evaluated 28 pairs of hypothetical new medicines, making a primary forced choice between each pair and a more flexible secondary choice, which permitted either, neither or both new medicines to be chosen. The performance of the resultant models was compared against previous AWMSG decisions. Forty-one out of a total of 80 past and present members of AWMSG appraisal committees completed the DCE. The incremental cost effectiveness of new medicines, and the QALY gains they provide, significantly (p < 0.0001) influence recommendations. Committee members were willing to accept higher incremental cost-effectiveness ratios and lower QALY gains for medicines that treat disease impacting primarily upon survival rather than quality of life, and where uncertainty in the cost-effectiveness estimates has been thoroughly explored. The number of patients to be treated by the new medicine did not exert a significant influence upon recommendations. The use of a flexible-choice question format revealed a different preference structure to the forced-choice format, but the performance of the two models was similar. Aggregate decisions of the AWMSG were well predicted by both models, but their sensitivity (64 %, 68 %) and specificity (55 %, 64 %) were limited. A willingness to trade the cost effectiveness and QALY gains against other factors indicates that economic efficiency and QALY maximisation are not the only considerations of committee members when making recommendations on the use of medicines in Wales. On average, appraisal committee members' stated preferences appear consistent with their actual decision-making behaviours, providing support for the external validity of our DCEs. However, as health technology assessment involves complex decision-making processes, and each individual recommendation may be influenced to varying degrees by a multitude of different considerations, the ability of our models to predict individual medicine recommendations is more limited.

Women's preferences for childbirth experiences in the Republic of Ireland; a mixed methods study.

PubMed

Larkin, Patricia; Begley, Cecily M; Devane, Declan

2017-01-10

How women experience childbirth is acknowledged as critical to the postnatal wellbeing of mother and baby. However there is a knowledge deficit in identifying the important elements of these experiences in order to enhance care. This study elicits women's preferences for the most important elements of their childbirth experiences. A mixed methods design was used. An initial qualitative phase (reported previously) was followed by a second quantitative one using a discrete choice experiment (DCE), which is reported on here. Participants who had experienced labour, were over 18 and had a healthy baby were recruited from four randomly selected and one pilot hospital in the Republic of Ireland. Data were collected by means of a DCE survey instrument. Questions were piloted, refined, and then arranged in eight pair-wise scenarios. Women identified their preferences by choosing one scenario over another. Nine hundred and five women were sent the DCE three months after childbirth, with a response rate of 59.3% (N =531). Women clearly identified priorities for their childbirth experiences as: the availability of pain relief, partnership with the midwife, and individualised care being the most important attributes. In the context of other choices, women rated decision-making, presence of a consultant, and interventions as less important elements. Comments from open questions provided contextual information about their choices. Most women did not want to be typified as wanting the dichotomy of 'all natural' or 'all technology' births but wanted 'the best of both worlds'. The results suggest that availability of pain relief was the most important element of women's childbirth experiences, and superseded all other elements including partnership with the midwife which was the second most important attribute. The preferences identified might reflect the busy medicalised hospital environments, in which the vast majority of women had given birth, and may differ in settings such as midwifery led care or home births.

Managing Minor Ailments; The Public's Preferences for Attributes of Community Pharmacies. A Discrete Choice Experiment.

PubMed

Porteous, Terry; Ryan, Mandy; Bond, Christine; Watson, Margaret; Watson, Verity

2016-01-01

Demand for health services continues to rise. Greater use of community pharmacy services instead of medical services for minor ailments could help relieve pressure on healthcare providers in high-cost settings. Community pharmacies are recognised sources of treatment and advice for people wishing to manage these ailments. However, increasing the public's use of pharmacy services may depend on attributes of pharmacies and their staff. This study aimed to determine the general public's relative preferences for community pharmacy attributes using a discrete choice experiment (DCE). A UK-wide DCE survey of the general public was conducted using face-to-face computer-assisted personal interviews. Attributes and levels for the DCE were informed by a literature review and a cohort study of community pharmacy customers. The context for the experiment was a minor ailment scenario describing flu-like symptoms. The DCE choice sets described two hypothetical community pharmacy services; respondents were asked to choose which (if either) of the two pharmacies they would prefer to help them manage symptoms. Data from 1,049 interviews were analysed using an error components logit model. Willingness to pay (WTP), a monetary measure of benefit, was estimated for the different attribute levels. When seeking help or treatment for flu-like symptoms, respondents most valued a pharmacy service that would improve their understanding and management of symptoms (WTP = £6.28), provided by staff who are trained (WTP (pharmacist) = £2.63: WTP(trained assistant) = £3.22), friendly and approachable (WTP = £3.38). Waiting time, pharmacy location and availability of parking also contributed to respondents' preferences. WTP for a service comprising the best possible combination of attributes and levels was calculated as £55.43. Attributes of a community pharmacy and its staff may influence people's decisions about which pharmacy they would visit to access treatment and advice for minor ailments. In line with the public's preferences, offering community pharmacy services that help people to better understand and manage symptoms, are provided promptly by trained staff who are friendly and approachable, and in a local setting with easy access to parking, has the potential to increase uptake amongst those seeking help to manage minor ailments. In this way it may be possible to shift demand away from high-cost health services and make more efficient use of scarce public resources.

Trading off dietary choices, physical exercise and cardiovascular disease risks.

PubMed

Grisolía, José M; Longo, Alberto; Boeri, Marco; Hutchinson, George; Kee, Frank

2013-09-01

Despite several decades of decline, cardiovascular diseases are still the most common causes of death in Western societies. Sedentary living and high fat diets contribute to the prevalence of cardiovascular diseases. This paper analyses the trade-offs between lifestyle choices defined in terms of diet, physical activity, cost, and risk of cardiovascular disease that a representative sample of the population of Northern Ireland aged 40-65 are willing to make. Using computer assisted personal interviews, we survey 493 individuals at their homes using a Discrete Choice Experiment (DCE) questionnaire administered between February and July 2011 in Northern Ireland. Unlike most DCE studies for valuing public health programmes, this questionnaire uses a tailored exercise, based on the individuals' baseline choices. A "fat screener" module in the questionnaire links personal cardiovascular disease risk to each specific choice set in terms of dietary constituents. Individuals are informed about their real status quo risk of a fatal cardiovascular event, based on an initial set of health questions. Thus, actual risks, real diet and exercise choices are the elements that constitute the choice task. Our results show that our respondents are willing to pay for reducing mortality risk and, more importantly, are willing to change physical exercise and dietary behaviours. In particular, we find that to improve their lifestyles, overweight and obese people would be more likely to do more physical activity than to change their diets. Therefore, public policies aimed to target obesity and its related illnesses in Northern Ireland should invest public money in promoting physical activity rather than healthier diets. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effect of premium, copayments, and health status on the choice of health plans.

PubMed

Naessens, James M; Khan, Mahmud; Shah, Nilay D; Wagie, Amy; Pautz, Rebecca A; Campbell, Claudia R

2008-10-01

Explore effects of comorbidity and prior health care utilization on choice of employee health plans with different levels of cost sharing. Mayo Clinic employees in Rochester, Minnesota (MCR) under age 65 in January 2004; N = 20,379. Assessment of a natural experiment where self-funded medical care benefit options were changed to contain costs within a large medical group practice. Before the change, most employees were enrolled in a plan with first dollar coverage, while 18% had a plan with copays and deductibles. In 2004, 3 existing plans were replaced by 2 new options, one with lower premiums and higher out-of-pocket costs and the other with higher premiums, a lower coinsurance rate, and lower out-of-pocket maximums. Data on employees were merged across insurance claims, medical records, eligibility files, and employment files for 2003 and 2004. As the number of chronic comorbidities among family members increased, the probability of choosing high-premium option also increased. Seventy-two percent of employees with at least 1 family member with comorbidity chose the high-cost option versus 54.7% of employees with no comorbidities. High-premium and low-premium plans seem to subdivide population into discrete risk categories, which may adversely affect the future stability of the insurance plan options. Various factors affect decision making of employees regarding the choice of plan with different levels of cost-sharing. In a natural experiment setting where all options were redesigned, the health status of employees and their dependents played a very significant role in plan choice.

Patient preferences for community pharmacy asthma services: a discrete choice experiment.

PubMed

Naik-Panvelkar, Pradnya; Armour, Carol; Rose, John M; Saini, Bandana

2012-10-01

Specialized community pharmacy services, involving the provision of disease state management and care by pharmacists, have been developed and trialled and have demonstrated very good health outcomes. Most of these services have been developed from a healthcare professional perspective. However, for the future uptake and long-term sustainability of these services as well as for better and sustained health outcomes for patients, it is vital to gain an understanding of patients' preferences. We can then structure healthcare services to match these preferences and needs rather than around clinical viewpoints alone. The aim of this study was to elicit patient preferences for pharmacy-based specialized asthma services using a discrete choice experiment and to explore the value/importance that patients place on the different attributes of the asthma service. The existence of preference heterogeneity in the population was also investigated. The study was conducted with asthma patients who had recently experienced a specialized asthma management service at their pharmacy in New South Wales, Australia. Pharmacists delivering the asthma service mailed out the discrete choice questionnaires to participating patients at the end of 6 months of service provision. A latent class (LC) model was used to investigate each patient's strength of preference and preference heterogeneity for several key attributes related to asthma service provision: frequency of visits, access to pharmacist, interaction with pharmacy staff, availability of a private area for consultation, provision of lung function testing, type and depth of advice provision, number of days with asthma symptoms and cost of service. Eighty useable questionnaires (of 170 questionnaires sent out) were received (response rate 47.1%). The study identified various key elements of asthma services important to patients. Further, the LC analysis revealed three classes with differing patient preferences for levels of asthma service provision. Patients in the Minimalistic Model class valued provision of lung function testing and preferred more frequent service visits. Cost of service had a negative effect on service preference for patients in this class. Patients in the Partial Model class mainly derived utility from the provision of lung function testing and comprehensive advice at the pharmacy and also wanted more frequent service visits. The Holistic Model class patients considered all attributes of the service to be important when making a choice. While the majority of the service attributes had a positive effect on preference for patients in this class, cost of service and days with symptoms of asthma had a negative effect on service preference. These patients also preferred fewer service visits. The study identified various key attributes that are important to patients with respect to community pharmacy-based asthma services. The results also demonstrate the existence of preference heterogeneity in the population. Asthma service providers need to take these findings into consideration in the design and development of future service models so as to increase their uptake and ensure their long-term sustainability.

Applications of algebraic topology to compatible spatial discretizations.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bochev, Pavel Blagoveston; Hyman, James M.

We provide a common framework for compatible discretizations using algebraic topology to guide our analysis. The main concept is the natural inner product on cochains, which induces a combinatorial Hodge theory. The framework comprises of mutually consistent operations of differentiation and integration, has a discrete Stokes theorem, and preserves the invariants of the DeRham cohomology groups. The latter allows for an elementary calculation of the kernel of the discrete Laplacian. Our framework provides an abstraction that includes examples of compatible finite element, finite volume and finite difference methods. We describe how these methods result from the choice of a reconstructionmore » operator and when they are equivalent.« less

Multiple-Choice versus Constructed-Response Tests in the Assessment of Mathematics Computation Skills.

ERIC Educational Resources Information Center

Gadalla, Tahany M.

The equivalence of multiple-choice (MC) and constructed response (discrete) (CR-D) response formats as applied to mathematics computation at grade levels two to six was tested. The difference between total scores from the two response formats was tested for statistical significance, and the factor structure of items in both response formats was…

An Empirical Investigation of Occupational Choice and Human Capital Accumulation at Mid-Life

ERIC Educational Resources Information Center

Xue, Yu

2010-01-01

Individual variation in labor supply can arise from more than just a choice among discrete occupation groups, especially given the joint process of wage determination and time allocation. Other factors can include differential preferences for earnings, the time length of work and other related occupational attributes. Using data from the Wisconsin…

Species-specific preferences of German recreational anglers for freshwater fishing experiences, with emphasis on the intrinsic utilities of fish stocking and wild fishes.

PubMed

Arlinghaus, R; Beardmore, B; Riepe, C; Meyerhoff, J; Pagel, T

2014-12-01

To answer the question, whether anglers have an intrinsic preference for stocking or a preference for catch outcomes (e.g. catch rates) believed to be maintained by stocking, a discrete choice experiment was conducted among a sample of anglers (n = 1335) in Lower Saxony, Germany. After controlling for catch aspects of the fishing experience, no significant influence of two stocking attributes (stocking frequency and composition of the catch in terms of wild v. hatchery fishes) on the utility gained from fishing was found for any of the freshwater species that were studied. It was concluded that the previously documented large appreciation of fish stocking by anglers may be indicative of an underlying preference for sufficiently high catches rather than reflect an intrinsic preference for stocking or the catching of wild fishes per se. © 2014 The Fisheries Society of the British Isles.

A Conditional Curie-Weiss Model for Stylized Multi-group Binary Choice with Social Interaction

NASA Astrophysics Data System (ADS)

Opoku, Alex Akwasi; Edusei, Kwame Owusu; Ansah, Richard Kwame

2018-04-01

This paper proposes a conditional Curie-Weiss model as a model for decision making in a stylized society made up of binary decision makers that face a particular dichotomous choice between two options. Following Brock and Durlauf (Discrete choice with social interaction I: theory, 1955), we set-up both socio-economic and statistical mechanical models for the choice problem. We point out when both the socio-economic and statistical mechanical models give rise to the same self-consistent equilibrium mean choice level(s). Phase diagram of the associated statistical mechanical model and its socio-economic implications are discussed.

Quantity judgments of sequentially presented food items by capuchin monkeys (Cebus apella).

PubMed

Evans, Theodore A; Beran, Michael J; Harris, Emily H; Rice, Daniel F

2009-01-01

Recent assessments have shown that capuchin monkeys, like chimpanzees and other Old World primate species, are sensitive to quantitative differences between sets of visible stimuli. In the present study, we examined capuchins' performance in a more sophisticated quantity judgment task that required the ability to form representations of food quantities while viewing the quantities only one piece at a time. In three experiments, we presented monkeys with the choice between two sets of discrete homogeneous food items and allowed the monkeys to consume the set of their choice. In Experiments 1 and 2, monkeys compared an entirely visible food set to a second set, presented item-by-item into an opaque container. All monkeys exhibited high accuracy in choosing the larger set, even when the entirely visible set was presented last, preventing the use of one-to-one item correspondence to compare quantities. In Experiment 3, monkeys compared two sets that were each presented item-by-item into opaque containers, but at different rates to control for temporal cues. Some monkeys performed well in this experiment, though others exhibited near-chance performance, suggesting that this species' ability to form representations of food quantities may be limited compared to previously tested species such as chimpanzees. Overall, these findings support the analog magnitude model of quantity representation as an explanation for capuchin monkeys' quantification of sequentially presented food items.

Inclusiveness in the health economic evaluation space.

PubMed

Ryan, Mandy; Gerard, Karen

2014-05-01

This paper presents an overview of Gavin Mooney's contributions to broadening the evaluative space in health economics. It outlines how Mooney's ideas have encouraged many, including ourselves, to expand the conventional QALYs/health gain approach and look more broadly at what it is that is of value from health services. We reflect on Mooney's contributions to debates around cost-effectiveness analysis, Quality Adjusted Life Years (QALYs) and cost-utility analysis as well as his contribution to the development and application of contingent valuation and discrete choice experiments in health economics. We conclude by suggesting important avenues for future research to take forward Mooney's work. Copyright © 2014 Elsevier Ltd. All rights reserved.

The effects of physical activity on impulsive choice: Influence of sensitivity to reinforcement amount and delay

PubMed Central

Strickland, Justin C.; Feinstein, Max A.; Lacy, Ryan T.; Smith, Mark A.

2016-01-01

Impulsive choice is a diagnostic feature and/or complicating factor for several psychological disorders and may be examined in the laboratory using delay-discounting procedures. Recent investigators have proposed using quantitative measures of analysis to examine the behavioral processes contributing to impulsive choice. The purpose of this study was to examine the effects of physical activity (i.e., wheel running) on impulsive choice in a single-response, discrete-trial procedure using two quantitative methods of analysis. To this end, rats were assigned to physical activity or sedentary groups and trained to respond in a delay-discounting procedure. In this procedure, one lever always produced one food pellet immediately, whereas a second lever produced three food pellets after a 0, 10, 20, 40, or 80-second delay. Estimates of sensitivity to reinforcement amount and sensitivity to reinforcement delay were determined using (1) a simple linear analysis and (2) an analysis of logarithmically transformed response ratios. Both analyses revealed that physical activity decreased sensitivity to reinforcement amount and sensitivity to reinforcement delay. These findings indicate that (1) physical activity has significant but functionally opposing effects on the behavioral processes that contribute to impulsive choice and (2) both quantitative methods of analysis are appropriate for use in single-response, discrete-trial procedures. PMID:26964905

The association between general practitioner participation in joint teleconsultations and rates of referral: a discrete choice experiment.

PubMed

Cravo Oliveira, Tiago; Barlow, James; Bayer, Steffen

2015-04-21

Joint consultations - such as teleconsultations - provide opportunities for continuing education of general practitioners (GPs). It has been reported this form of interactive case-based learning may lead to fewer GP referrals, yet these studies have relied on expert opinion and simple frequencies, without accounting for other factors known to influence referrals. We use a survey-based discrete choice experiment of GPs' referral preferences to estimate how referral rates are associated with participation in joint teleconsultations, explicitly controlling for a number of potentially confounding variables. We distributed questionnaires at two meetings of the Portuguese Association of General Practice. GPs were presented with descriptions of patients with dermatological lesions and asked whether they would refer based on the waiting time, the distance to appointment, and pressure from patients for a referral. We analysed GPs' responses to multiple combinations of these factors, coupled with information on GP and practice characteristics, using a binary logit model. We estimated the probabilities of referral of different lesions using marginal effects. Questionnaires were returned by 44 GPs, giving a total of 721 referral choices. The average referral rate for the 11 GPs (25%) who had participated in teleconsultations was 68.1% (range 53-88%), compared to 74.4% (range 47-100%) for the remaining physicians. Participation in teleconsultations was associated with reductions in the probabilities of referral of 17.6% for patients presenting with keratosis (p = 0.02), 42.3% for psoriasis (p < 0.001), 8.4% for melanoma (p = 0.14), and 5.4% for naevus (p = 0.19). The results indicate that GP participation in teleconsultations is associated with overall reductions in referral rates and in variation across GPs, and that these effects are robust to the inclusion of other factors known to influence referrals. The reduction in range, coupled with different effects for different clinical presentations, may suggest an educational effect. However, more research is needed to establish whether there are causal relationships between participation in teleconsultations, continuing education, and referral rates.

Public preferences for establishing nephrology facilities in Greenland: estimating willingness-to-pay using a discrete choice experiment.

PubMed

Kjær, Trine; Bech, Mickael; Kronborg, Christian; Mørkbak, Morten Raun

2013-10-01

At present there are no nephrology facilities in Greenland. Greenlandic patients with renal failure needing dialysis thus have to travel to Denmark to obtain treatment. For patients in haemodialysis this necessitates a permanent residence in Denmark. Our study was aimed at examining Greenlanders' preferences for establishing nephrology facilities in Greenland at Queen Ingrid's Hospital in Nuuk, and to estimate the associated change in welfare. Preferences were elicited using a discrete choice experiment (DCE). A random sample of 500 individuals of the general population was sent a postal questionnaire in which they were asked to consider the trade-offs of establishing nephrology facilities in Greenland as opposed to the current situation. This involved trading off the benefits of having such facilities in their home country against the costs of the intervention. Besides including a payment attribute described in terms of incremental tax payment, the DCE included two interventions attributes related to (1) the organisation of labour, and (2) the physical settings of the patients. Respondents succeeded in answering the DCE despite cultural and linguistic disparity. We found that all the included attributes had a significant effect on respondents' choices, and that respondents' answers to the DCE were in keeping with their values as stated in the questionnaire. DCE data was analyzed using a random parameter logit model reparametrized in willingness-to-pay space. The results showed that establishing facilities in Greenland were preferred to the current treatment in Denmark. The welfare estimate from the DCE, at DKK 18.74 million, exceeds the estimated annual costs of establishing treatment facilities for patients with chronic renal failure. Given the estimated confidence interval this result seems robust. Establishing facilities in Greenland therefore would appear to be welfare-improving, deriving positive net benefits. Despite the relatively narrow policy focus, we believe that our findings provide some insight into individuals' preferences for decentralization of public services and on citizens' views of 'self-governance' that go beyond the case of Greenland. More generally, this paper illustrates how DCE can be applied successfully to developing countries with culturally, demographically, and geographically distinct features.

Constructing experimental designs for discrete-choice experiments: report of the ISPOR Conjoint Analysis Experimental Design Good Research Practices Task Force.

PubMed

Reed Johnson, F; Lancsar, Emily; Marshall, Deborah; Kilambi, Vikram; Mühlbacher, Axel; Regier, Dean A; Bresnahan, Brian W; Kanninen, Barbara; Bridges, John F P

2013-01-01

Stated-preference methods are a class of evaluation techniques for studying the preferences of patients and other stakeholders. While these methods span a variety of techniques, conjoint-analysis methods-and particularly discrete-choice experiments (DCEs)-have become the most frequently applied approach in health care in recent years. Experimental design is an important stage in the development of such methods, but establishing a consensus on standards is hampered by lack of understanding of available techniques and software. This report builds on the previous ISPOR Conjoint Analysis Task Force Report: Conjoint Analysis Applications in Health-A Checklist: A Report of the ISPOR Good Research Practices for Conjoint Analysis Task Force. This report aims to assist researchers specifically in evaluating alternative approaches to experimental design, a difficult and important element of successful DCEs. While this report does not endorse any specific approach, it does provide a guide for choosing an approach that is appropriate for a particular study. In particular, it provides an overview of the role of experimental designs for the successful implementation of the DCE approach in health care studies, and it provides researchers with an introduction to constructing experimental designs on the basis of study objectives and the statistical model researchers have selected for the study. The report outlines the theoretical requirements for designs that identify choice-model preference parameters and summarizes and compares a number of available approaches for constructing experimental designs. The task-force leadership group met via bimonthly teleconferences and in person at ISPOR meetings in the United States and Europe. An international group of experimental-design experts was consulted during this process to discuss existing approaches for experimental design and to review the task force's draft reports. In addition, ISPOR members contributed to developing a consensus report by submitting written comments during the review process and oral comments during two forum presentations at the ISPOR 16th and 17th Annual International Meetings held in Baltimore (2011) and Washington, DC (2012). Copyright © 2013 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Accounting for Scale Heterogeneity in Healthcare-Related Discrete Choice Experiments when Comparing Stated Preferences: A Systematic Review.

PubMed

Wright, Stuart J; Vass, Caroline M; Sim, Gene; Burton, Michael; Fiebig, Denzil G; Payne, Katherine

2018-02-28

Scale heterogeneity, or differences in the error variance of choices, may account for a significant amount of the observed variation in the results of discrete choice experiments (DCEs) when comparing preferences between different groups of respondents. The aim of this study was to identify if, and how, scale heterogeneity has been addressed in healthcare DCEs that compare the preferences of different groups. A systematic review identified all healthcare DCEs published between 1990 and February 2016. The full-text of each DCE was then screened to identify studies that compared preferences using data generated from multiple groups. Data were extracted and tabulated on year of publication, samples compared, tests for scale heterogeneity, and analytical methods to account for scale heterogeneity. Narrative analysis was used to describe if, and how, scale heterogeneity was accounted for when preferences were compared. A total of 626 healthcare DCEs were identified. Of these 199 (32%) aimed to compare the preferences of different groups specified at the design stage, while 79 (13%) compared the preferences of groups identified at the analysis stage. Of the 278 included papers, 49 (18%) discussed potential scale issues, 18 (7%) used a formal method of analysis to account for scale between groups, and 2 (1%) accounted for scale differences between preference groups at the analysis stage. Scale heterogeneity was present in 65% (n = 13) of studies that tested for it. Analytical methods to test for scale heterogeneity included coefficient plots (n = 5, 2%), heteroscedastic conditional logit models (n = 6, 2%), Swait and Louviere tests (n = 4, 1%), generalised multinomial logit models (n = 5, 2%), and scale-adjusted latent class analysis (n = 2, 1%). Scale heterogeneity is a prevalent issue in healthcare DCEs. Despite this, few published DCEs have discussed such issues, and fewer still have used formal methods to identify and account for the impact of scale heterogeneity. The use of formal methods to test for scale heterogeneity should be used, otherwise the results of DCEs potentially risk producing biased and potentially misleading conclusions regarding preferences for aspects of healthcare.

Adolescent, parent and societal preferences and willingness to pay for meningococcal B vaccine: A Discrete Choice Experiment.

PubMed

Marshall, H S; Chen, G; Clarke, M; Ratcliffe, J

2016-01-27

Meningococcal B (MenB) vaccines have been licensed in many countries with private purchase the only option until recently, when a funded programme was introduced in the UK. The aim of this study was to explore adolescent/parental values for a variety of salient vaccine attributes (cost, effectiveness, side effect profile) to assess preferences and willingness-to-pay (WTP) for a MenB vaccine. A national cross-sectional population study was conducted in Australia using Discrete Choice Experiment methodology to assess adolescent/parent/adult preferences for attributes related to MenB vaccine. 2003 adults and 502 adolescents completed the survey in 2013. The majority of participants were willing to be vaccinated with MenB vaccine with vaccination opt-out chosen by 11.9% of adolescents and parents, and 18.2% of non-parent adults. A mixed logit regression model examining adolescent/adult preferences indicated consistent findings; the higher the effectiveness, the longer the duration of protection, the less chance of adverse events and the lower the cost, the more likely respondents were to agree to vaccination. For an ideal MenB vaccine, including the most favoured level of each attribute summed together (90% effectiveness, 10 year duration, 1 injection, no adverse events) adolescents would pay AU$251.60 and parents AU$295.10. Adolescents and parents would pay AU$90.70 or AU$127.20 for 90% vaccine effectiveness vs AU$18.50 or AU$16.70 for 70% effectiveness and would want to be financially compensated for 50% effectiveness; pay AU$63.30 or AU$76.40 for 10 years protection; and pay AU$48.50 or AU$49.20 for no vaccine related adverse events. A slight fever post vaccination was a preferred choice with parents and adolescents willing to pay AU$9.60 or AU$12.30 for this attribute. Vaccine effectiveness, adverse events and duration of immunity are important drivers for parental and adolescent decisions about WTP for MenB vaccine and should be included in discussions on the benefits, risks and cost. Copyright © 2015 Elsevier Ltd. All rights reserved.

Redesigning printed educational materials for primary care physicians: design improvements increase usability.

PubMed

Grudniewicz, Agnes; Bhattacharyya, Onil; McKibbon, K Ann; Straus, Sharon E

2015-11-04

Printed educational materials (PEMs) are a frequently used tool to disseminate clinical information and attempt to change behavior within primary care. However, their effect on clinician behavior is limited. In this study, we explored how PEMs can be redesigned to better meet the needs of primary care physicians (PCPs) and whether usability and selection can be increased when design principles and user preferences are used. We redesigned a publicly available PEM using physician preferences, design principles, and graphic designer support. We invited PCPs to select their preferred document between the redesigned and original versions in a discrete choice experiment, followed by an assessment of usability with the System Usability Scale and a think aloud process. We conducted this study in both a controlled and opportunistic setting to determine whether usability testing results vary by study location. Think aloud data was thematically analyzed, and results were interpreted using the Technology Acceptance Model. One hundred and eighty four PCPs participated in the discrete choice experiment at the 2014 Family Medicine Forum, a large Canadian conference for family physicians. Of these, 87.7 % preferred the redesigned version. Follow-up interviews were held with a randomly selected group of seven participants. We repeated this in a controlled setting in Toronto, Canada, with a set of 14 participants. Using the System Usability Scale, we found that usability scores were significantly increased with the redesign (p < 0.001). We also found that when PCPs were given the choice between the two versions, they selected the redesigned version as their preferred PEM more often than the original (p < 0.001). Results did not appear to differ between the opportunistic and controlled setting. We used the results of the think aloud process to add to a list of end user preferences developed in a previous study. We found that redesigning a PEM with user preferences and design principles can improve its usability and result in the PEM being selected more often than the original. We feel this finding supports the involvement of the user, application of design principles, and the assistance of a graphic designer in the development of PEMs.

Heterogeneity in general practitioners' preferences for quality improvement programs: a choice experiment and policy simulation in France.

PubMed

Ammi, Mehdi; Peyron, Christine

2016-12-01

Despite increasing popularity, quality improvement programs (QIP) have had modest and variable impacts on enhancing the quality of physician practice. We investigate the heterogeneity of physicians' preferences as a potential explanation of these mixed results in France, where the national voluntary QIP - the CAPI - has been cancelled due to its unpopularity. We rely on a discrete choice experiment to elicit heterogeneity in physicians' preferences for the financial and non-financial components of QIP. Using mixed and latent class logit models, results show that the two models should be used in concert to shed light on different aspects of the heterogeneity in preferences. In particular, the mixed logit demonstrates that heterogeneity in preferences is concentrated on the pay-for-performance component of the QIP, while the latent class model shows that physicians can be grouped in four homogeneous groups with specific preference patterns. Using policy simulation, we compare the French CAPI with other possible QIPs, and show that the majority of the physician subgroups modelled dislike the CAPI, while favouring a QIP using only non-financial interventions. We underline the importance of modelling preference heterogeneity in designing and implementing QIPs.

Do Sequentially-Presented Answer Options Prevent the Use of Testwiseness Cues on Continuing Medical Education Tests?

ERIC Educational Resources Information Center

Willing, Sonja; Ostapczuk, Martin; Musch, Jochen

2015-01-01

Testwiseness--that is, the ability to find subtle cues towards the solution by the simultaneous comparison of the available answer options--threatens the validity of multiple-choice (MC) tests. Discrete-option multiple-choice (DOMC) has recently been proposed as a computerized alternative testing format for MC tests, and presumably allows for a…

An integrated logit model for contamination event detection in water distribution systems.

PubMed

Housh, Mashor; Ostfeld, Avi

2015-05-15

The problem of contamination event detection in water distribution systems has become one of the most challenging research topics in water distribution systems analysis. Current attempts for event detection utilize a variety of approaches including statistical, heuristics, machine learning, and optimization methods. Several existing event detection systems share a common feature in which alarms are obtained separately for each of the water quality indicators. Unifying those single alarms from different indicators is usually performed by means of simple heuristics. A salient feature of the current developed approach is using a statistically oriented model for discrete choice prediction which is estimated using the maximum likelihood method for integrating the single alarms. The discrete choice model is jointly calibrated with other components of the event detection system framework in a training data set using genetic algorithms. The fusing process of each indicator probabilities, which is left out of focus in many existing event detection system models, is confirmed to be a crucial part of the system which could be modelled by exploiting a discrete choice model for improving its performance. The developed methodology is tested on real water quality data, showing improved performances in decreasing the number of false positive alarms and in its ability to detect events with higher probabilities, compared to previous studies. Copyright © 2015 Elsevier Ltd. All rights reserved.

Tracking Second Thoughts: Continuous and Discrete Revision Processes during Visual Lexical Decision

PubMed Central

Barca, Laura; Pezzulo, Giovanni

2015-01-01

We studied the dynamics of lexical decisions by asking participants to categorize lexical and nonlexical stimuli and recording their mouse movements toward response buttons during the choice. In a previous report we revealed greater trajectory curvature and attraction to competitors for Low Frequency words and Pseudowords. This analysis did not clarify whether the trajectory curvature in the two conditions was due to a continuous dynamic competition between the response alternatives or if a discrete revision process (a "change of mind") took place during the choice from an initially selected response to the opposite one. To disentangle these two possibilities, here we analyse the velocity and acceleration profiles of mouse movements during the choice. Pseudowords' peak movement velocity occurred with 100ms delay with respect to words and Letters Strings. Acceleration profile for High and Low Frequency words and Letters Strings exhibited a butterfly plot with one acceleration peak at 400ms and one deceleration peak at 650ms. Differently, Pseudowords' acceleration profile had double positive peaks (at 400 and 600ms) followed by movement deceleration, in correspondence with changes in the decision from lexical to nonlexical response buttons. These results speak to different online processes during the categorization of Low Frequency words and Pseudowords, with a continuous competition process for the former and a discrete revision process for the latter. PMID:25699992

A Generalized Measurement Model to Quantify Health: The Multi-Attribute Preference Response Model

PubMed Central

Krabbe, Paul F. M.

2013-01-01

After 40 years of deriving metric values for health status or health-related quality of life, the effective quantification of subjective health outcomes is still a challenge. Here, two of the best measurement tools, the discrete choice and the Rasch model, are combined to create a new model for deriving health values. First, existing techniques to value health states are briefly discussed followed by a reflection on the recent revival of interest in patients’ experience with regard to their possible role in health measurement. Subsequently, three basic principles for valid health measurement are reviewed, namely unidimensionality, interval level, and invariance. In the main section, the basic operation of measurement is then discussed in the framework of probabilistic discrete choice analysis (random utility model) and the psychometric Rasch model. It is then shown how combining the main features of these two models yields an integrated measurement model, called the multi-attribute preference response (MAPR) model, which is introduced here. This new model transforms subjective individual rank data into a metric scale using responses from patients who have experienced certain health states. Its measurement mechanism largely prevents biases such as adaptation and coping. Several extensions of the MAPR model are presented. The MAPR model can be applied to a wide range of research problems. If extended with the self-selection of relevant health domains for the individual patient, this model will be more valid than existing valuation techniques. PMID:24278141

The Influences of Landscape Features on Visitation of Hospital Green Spaces-A Choice Experiment Approach.

PubMed

Chang, Kaowen Grace; Chien, Hungju

2017-07-05

Studies have suggested that visiting and viewing landscaping at hospitals accelerates patient's recovery from surgery and help staff's recovery from mental fatigue. To plan and construct such landscapes, we need to unravel landscape features desirable to different groups so that the space can benefit a wide range of hospital users. Using discrete choice modeling, we developed experimental choice sets to investigate how landscape features influence the visitations of different users in a large regional hospital in Taiwan. The empirical survey provides quantitative estimates of the influence of each landscape feature on four user groups, including patients, caregivers, staff, and neighborhood residents. Our findings suggest that different types of features promote visits from specific user groups. Landscape features facilitating physical activities effectively encourage visits across user groups especially for caregivers and staff. Patients in this study specify a strong need for contact with nature. The nearby community favors the features designed for children's play and family activities. People across user groups value the features that provide a mitigated microclimate of comfort, such as a shelter. Study implications and limitations are also discussed. Our study provides information essential for creating a better healing environment in a hospital setting.

Age and choice in health insurance: evidence from a discrete choice experiment.

PubMed

Becker, Karolin; Zweifel, Peter

2008-01-01

A uniform package of benefits and uniform cost sharing are elements of regulation inherent in most social health insurance systems. Both elements risk burdening the population with a welfare loss if preferences for risk and insurance attributes differ. This suggests the introduction of more choice in social health insurance packages may be advantageous; however, it is widely believed that this would not benefit the elderly.A representative telephone survey of 1000 people aged >24 years living in the German- and French-speaking parts of Switzerland was conducted. Participants were asked to compare the status quo (i.e. their current insurance contract) with ten hypothetical alternatives. In addition, participants were asked questions concerning utilization of healthcare services; overall satisfaction with the healthcare system, insurer and insurance policy; and a general preference for new elements in the insurance package. Socioeconomic variables surveyed were age, sex, total household income, education (seven categories ranging from primary school to university degree), place of residence, occupation, and marital status. To examine the relationship between age and willingness to pay (WTP) for additional options in Swiss social health insurance.A representative telephone survey of 1000 people aged >24 years living in the German- and French-speaking parts of Switzerland was conducted. Participants were asked to compare the status quo (i.e. their current insurance contract) with ten hypothetical alternatives. In addition, participants were asked questions concerning utilization of healthcare services; overall satisfaction with the healthcare system, insurer and insurance policy; and a general preference for new elements in the insurance package. Socioeconomic variables surveyed were age, sex, total household income, education (seven categories ranging from primary school to university degree), place of residence, occupation, and marital status. A discrete choice experiment was developed using six attributes (deductibles, co-payment, access to alternative medicines, medication choice, access to innovation, and monthly premium) that are currently in debate within the context of Swiss health insurance. These attributes have been shown to be important in the choice of insurance contract. Using statistical design optimization procedures, the number of choice sets was reduced to 27 and randomly split into three groups. One choice was included twice to test for consistency. Two random effects probit models were developed: a simple model where marginal utilities and WTP values were not allowed to vary according to socioeconomic characteristics, and a more complex model where the values were permitted to depend on socioeconomic variables.A representative telephone survey of 1000 people aged >24 years living in the German- and French-speaking parts of Switzerland was conducted. Participants were asked to compare the status quo (i.e. their current insurance contract) with ten hypothetical alternatives. In addition, participants were asked questions concerning utilization of healthcare services; overall satisfaction with the healthcare system, insurer and insurance policy; and a general preference for new elements in the insurance package. Socioeconomic variables surveyed were age, sex, total household income, education (seven categories ranging from primary school to university degree), place of residence, occupation, and marital status. All chosen elements proved relevant for choice in the simple model. Accounting for socioeconomic characteristics in the comprehensive model reveals preference heterogeneity for contract attributes, but also for the propensity to consider deviating from the status quo and choosing an alternative health insurance contract. The findings suggest that while the elderly do exhibit a stronger status quo bias than younger age groups, they require less rather than more specific compensation for selected cutbacks, indicating a potential for contracts that induce self-rationing in return for lower premiums.

Measuring customer preferences in the German statutory health insurance.

PubMed

Pendzialek, Jonas B; Simic, Dusan; Stock, Stephanie

2017-09-01

This paper investigates consumer preferences in the German statutory health insurance market. It further aims to test whether preferences differ by age and health status. Evidence is provided by a discrete choice experiment conducted in 2014 using the six most important attributes in sickness fund competition and ten random generated choice sets per participant. Price is found to be the most important attribute followed by additional benefits, managed care programmes, and distance to nearest branch. Other positive attributes of sickness funds are found to balance out a higher price, which would allow a sickness fund to position itself as high quality. However, significant differences in preferences were found between age and health status group. In particular, compromised health is associated with higher preference for illness-related additional benefits and less distance to the lowest branch, but lower preference for a lower price. Based on these differences, a distinct sickness fund offer could be constructed that would allow passive risk selection.

Functional forms and price elasticities in a discrete continuous choice model of the residential water demand

NASA Astrophysics Data System (ADS)

Vásquez Lavín, F. A.; Hernandez, J. I.; Ponce, R. D.; Orrego, S. A.

2017-07-01

During recent decades, water demand estimation has gained considerable attention from scholars. From an econometric perspective, the most used functional forms include log-log and linear specifications. Despite the advances in this field and the relevance for policymaking, little attention has been paid to the functional forms used in these estimations, and most authors have not provided justifications for their selection of functional forms. A discrete continuous choice model of the residential water demand is estimated using six functional forms (log-log, full-log, log-quadratic, semilog, linear, and Stone-Geary), and the expected consumption and price elasticity are evaluated. From a policy perspective, our results highlight the relevance of functional form selection for both the expected consumption and price elasticity.

The Effect of Including an Opt-Out Option in Discrete Choice Experiments

PubMed Central

Veldwijk, Jorien; Lambooij, Mattijs S.; de Bekker-Grob, Esther W.; Smit, Henriëtte A.; de Wit, G. Ardine

2014-01-01

Objective to determine to what extent the inclusion of an opt-out option in a DCE may have an effect on choice behaviour and therefore might influence the attribute level estimates, the relative importance of the attributes and calculated trade-offs. Methods 781 Dutch Type 2 Diabetes Mellitus patients completed a questionnaire containing nine choice tasks with an opt-out option and nice forced choice tasks. Mixed-logit models were used to estimate the relative importance of the five lifestyle program related attributes that were included. Willingness to pay (WTP) values were calculated and it was tested whether results differed between respondents who answered the choice tasks with an opt-out option in the first or second part of the questionnaire. Results 21.4% of the respondents always opted out. Respondents who were given the opt-out option in the first part of the questionnaire as well as lower educated respondents significantly more often opted out. For both the forced and unforced choice model, different attributes showed significant estimates, the relative importance of the attributes was equal. However, due to differences in relative importance weights, the WTP values for the PA schedule differed significantly between both datasets. Conclusions Results show differences in opting out based on the location of the opt-out option and respondents' educational level; this resulted in small differences between the forced and unforced choice model. Since respondents seem to learn from answering forced choice tasks, a dual response design might result in higher data quality compared to offering a direct opt-out option. Future research should empirically explore how choice sets should be presented to make them as easy and less complex as possible in order to reduce the proportion of respondents that opts-out due to choice task complexity. Moreover, future research should debrief respondents to examine the reasons for choosing the opt-out alternative. PMID:25365169

The effect of including an opt-out option in discrete choice experiments.

PubMed

Veldwijk, Jorien; Lambooij, Mattijs S; de Bekker-Grob, Esther W; Smit, Henriëtte A; de Wit, G Ardine

2014-01-01

to determine to what extent the inclusion of an opt-out option in a DCE may have an effect on choice behaviour and therefore might influence the attribute level estimates, the relative importance of the attributes and calculated trade-offs. 781 Dutch Type 2 Diabetes Mellitus patients completed a questionnaire containing nine choice tasks with an opt-out option and nice forced choice tasks. Mixed-logit models were used to estimate the relative importance of the five lifestyle program related attributes that were included. Willingness to pay (WTP) values were calculated and it was tested whether results differed between respondents who answered the choice tasks with an opt-out option in the first or second part of the questionnaire. 21.4% of the respondents always opted out. Respondents who were given the opt-out option in the first part of the questionnaire as well as lower educated respondents significantly more often opted out. For both the forced and unforced choice model, different attributes showed significant estimates, the relative importance of the attributes was equal. However, due to differences in relative importance weights, the WTP values for the PA schedule differed significantly between both datasets. Results show differences in opting out based on the location of the opt-out option and respondents' educational level; this resulted in small differences between the forced and unforced choice model. Since respondents seem to learn from answering forced choice tasks, a dual response design might result in higher data quality compared to offering a direct opt-out option. Future research should empirically explore how choice sets should be presented to make them as easy and less complex as possible in order to reduce the proportion of respondents that opts-out due to choice task complexity. Moreover, future research should debrief respondents to examine the reasons for choosing the opt-out alternative.

Persistent palatable food preference in rats with a history of limited and extended access to methamphetamine self-administration

PubMed Central

Caprioli, Daniele; Zeric, Tamara; Thorndike, Eric B; Venniro, Marco

2015-01-01

Recent studies have shown that when given a mutually exclusive choice between cocaine and palatable foods most rats prefer the non-drug rewards over cocaine. Here, we used a discrete choice procedure to assess whether palatable food preference generalizes to rats with a history of limited (3 hr/day) or extended (6 or 9 hr/day) access to methamphetamine self-administration. On different daily sessions, we trained rats to lever-press for either methamphetamine (0.1–0.2 mg/kg/infusion) or palatable food (5 pellets per reward delivery) for several weeks; regular food was freely available. We then assessed food-methamphetamine preference either during training, after priming methamphetamine injections (0.5–1.0 mg/kg), following a satiety manipulation (palatable food exposure in the home cage), or after 21 days of withdrawal from methamphetamine. We also assessed progressive ratio responding for palatable food and methamphetamine. We found that independent of the daily drug access conditions and the withdrawal period, the rats strongly preferred the palatable food over methamphetamine, even when they were given free access to the palatable food in the home cage. Intake of methamphetamine and progressive ratio responding for the drug, both of which increased or escalated over time, did not predict preference in the discrete choice test. Results demonstrate that most rats strongly prefer palatable food pellets over intravenous methamphetamine, confirming previous studies using discrete choice procedures with intravenous cocaine. Results also demonstrate that escalation of drug self-administration, a popular model of compulsive drug use, is not associated with a cardinal feature of human addiction of reduced behavioral responding for non-drug rewards. PMID:25582886

Persistent palatable food preference in rats with a history of limited and extended access to methamphetamine self-administration.

PubMed

Caprioli, Daniele; Zeric, Tamara; Thorndike, Eric B; Venniro, Marco

2015-09-01

Recent studies have shown that when given a mutually exclusive choice between cocaine and palatable foods, most rats prefer the non-drug rewards over cocaine. Here, we used a discrete choice procedure to assess whether palatable food preference generalizes to rats with a history of limited (3 hours/day) or extended (6 or 9 hours/day) access to methamphetamine self-administration. On different daily sessions, we trained rats to lever-press for either methamphetamine (0.1-0.2 mg/kg/infusion) or palatable food (five pellets per reward delivery) for several weeks; regular food was freely available. We then assessed food-methamphetamine preference either during training, after priming methamphetamine injections (0.5-1.0 mg/kg), following a satiety manipulation (palatable food exposure in the home cage) or after 21 days of withdrawal from methamphetamine. We also assessed progressive ratio responding for palatable food and methamphetamine. We found that independent of the daily drug access conditions and the withdrawal period, the rats strongly preferred the palatable food over methamphetamine, even when they were given free access to the palatable food in the home cage. Intake of methamphetamine and progressive ratio responding for the drug, both of which increased or escalated over time, did not predict preference in the discrete choice test. Results demonstrate that most rats strongly prefer palatable food pellets over intravenous methamphetamine, confirming previous studies using discrete choice procedures with intravenous cocaine. Results also demonstrate that escalation of drug self-administration, a popular model of compulsive drug use, is not associated with a cardinal feature of human addiction of reduced behavioral responding for non-drug rewards. © 2015 Society for the Study of Addiction.

Discrete Choice Model of Food Store Trips Using National Household Food Acquisition and Purchase Survey (FoodAPS).

PubMed

Hillier, Amy; Smith, Tony E; Whiteman, Eliza D; Chrisinger, Benjamin W

2017-09-27

Where households across income levels shop for food is of central concern within a growing body of research focused on where people live relative to where they shop, what they purchase and eat, and how those choices influence the risk of obesity and chronic disease. We analyzed data from the National Household Food Acquisition and Purchase Survey (FoodAPS) using a conditional logit model to determine where participants shop for food to be prepared and eaten at home and how individual and household characteristics of food shoppers interact with store characteristics and distance from home in determining store choice. Store size, whether or not it was a full-service supermarket, and the driving distance from home to the store constituted the three significant main effects on store choice. Overall, participants were more likely to choose larger stores, conventional supermarkets rather than super-centers and other types of stores, and stores closer to home. Interaction effects show that participants receiving Supplemental Nutrition Assistance Program (SNAP) were even more likely to choose larger stores. Hispanic participants were more likely than non-Hispanics to choose full-service supermarkets while White participants were more likely to travel further than non-Whites. This study demonstrates the value of explicitly spatial discrete choice models and provides evidence of national trends consistent with previous smaller, local studies.

Discrete Choice Model of Food Store Trips Using National Household Food Acquisition and Purchase Survey (FoodAPS)

PubMed Central

Hillier, Amy; Smith, Tony E.; Whiteman, Eliza D.

2017-01-01

Where households across income levels shop for food is of central concern within a growing body of research focused on where people live relative to where they shop, what they purchase and eat, and how those choices influence the risk of obesity and chronic disease. We analyzed data from the National Household Food Acquisition and Purchase Survey (FoodAPS) using a conditional logit model to determine where participants shop for food to be prepared and eaten at home and how individual and household characteristics of food shoppers interact with store characteristics and distance from home in determining store choice. Store size, whether or not it was a full-service supermarket, and the driving distance from home to the store constituted the three significant main effects on store choice. Overall, participants were more likely to choose larger stores, conventional supermarkets rather than super-centers and other types of stores, and stores closer to home. Interaction effects show that participants receiving Supplemental Nutrition Assistance Program (SNAP) were even more likely to choose larger stores. Hispanic participants were more likely than non-Hispanics to choose full-service supermarkets while White participants were more likely to travel further than non-Whites. This study demonstrates the value of explicitly spatial discrete choice models and provides evidence of national trends consistent with previous smaller, local studies. PMID:28953221

The effects of physical activity on impulsive choice: Influence of sensitivity to reinforcement amount and delay.

PubMed

Strickland, Justin C; Feinstein, Max A; Lacy, Ryan T; Smith, Mark A

2016-05-01

Impulsive choice is a diagnostic feature and/or complicating factor for several psychological disorders and may be examined in the laboratory using delay-discounting procedures. Recent investigators have proposed using quantitative measures of analysis to examine the behavioral processes contributing to impulsive choice. The purpose of this study was to examine the effects of physical activity (i.e., wheel running) on impulsive choice in a single-response, discrete-trial procedure using two quantitative methods of analysis. To this end, rats were assigned to physical activity or sedentary groups and trained to respond in a delay-discounting procedure. In this procedure, one lever always produced one food pellet immediately, whereas a second lever produced three food pellets after a 0, 10, 20, 40, or 80-s delay. Estimates of sensitivity to reinforcement amount and sensitivity to reinforcement delay were determined using (1) a simple linear analysis and (2) an analysis of logarithmically transformed response ratios. Both analyses revealed that physical activity decreased sensitivity to reinforcement amount and sensitivity to reinforcement delay. These findings indicate that (1) physical activity has significant but functionally opposing effects on the behavioral processes that contribute to impulsive choice and (2) both quantitative methods of analysis are appropriate for use in single-response, discrete-trial procedures. Copyright © 2016 Elsevier B.V. All rights reserved.

Spherical harmonics and rigged Hilbert spaces

NASA Astrophysics Data System (ADS)

Celeghini, E.; Gadella, M.; del Olmo, M. A.

2018-05-01

This paper is devoted to study discrete and continuous bases for spaces supporting representations of SO(3) and SO(3, 2) where the spherical harmonics are involved. We show how discrete and continuous bases coexist on appropriate choices of rigged Hilbert spaces. We prove the continuity of relevant operators and the operators in the algebras spanned by them using appropriate topologies on our spaces. Finally, we discuss the properties of the functionals that form the continuous basis.

The theory of planned behaviour and discrete food choices: a systematic review and meta-analysis.

PubMed

McDermott, Máirtín S; Oliver, Madalyn; Svenson, Alexander; Simnadis, Thomas; Beck, Eleanor J; Coltman, Tim; Iverson, Don; Caputi, Peter; Sharma, Rajeev

2015-12-30

The combination of economic and social costs associated with non-communicable diseases provide a compelling argument for developing strategies that can influence modifiable risk factors, such as discrete food choices. Models of behaviour, such as the Theory of Planned Behaviour (TPB) provide conceptual order that allows program designers and policy makers to identify the substantive elements that drive behaviour and design effective interventions. The primary aim of the current review was to examine the association between TPB variables and discrete food choice behaviours. A systematic literature search was conducted to identify relevant studies. Calculation of the pooled mean effect size (r(+)) was conducted using inverse-variance weighted, random effects meta-analysis. Heterogeneity across studies was assessed using the Q- and I(2)-statistics. Meta-regression was used to test the impact of moderator variables: type of food choice behaviour; participants' age and gender. A total of 42 journal articles and four unpublished dissertations met the inclusion criteria. TPB variables were found to have medium to large associations with both intention and behaviour. Attitudes had the strongest association with intention (r(+)  = 0.54) followed by perceived behavioural control (PBC, r(+)  = 0.42) and subjective norm (SN, r(+)  = 0.37). The association between intention and behaviour was r(+)  = 0.45 and between PBC and behaviour was r(+)  = 0.27. Moderator analyses revealed the complex nature of dietary behaviour and the factors that underpin individual food choices. Significantly higher PBC-behaviour associations were found for choosing health compromising compared to health promoting foods. Significantly higher intention-behaviour and PBC-behaviour associations were found for choosing health promoting foods compared to avoiding health compromising foods. Participant characteristics were also found to moderate associations within the model. Higher intention-behaviour associations were found for older, compared to younger age groups. The variability in the association of the TPB with different food choice behaviours uncovered by the moderator analyses strongly suggest that researchers should carefully consider the nature of the behaviour being exhibited prior to selecting a theory.

Consumer preferences for teledermoscopy screening to detect melanoma early.

PubMed

Spinks, Jean; Janda, Monika; Soyer, H Peter; Whitty, Jennifer A

2016-01-01

'Store and forward' teledermoscopy is a technology with potential advantages for melanoma screening. Any large-scale implementation of this technology is dependent on consumer acceptance. To investigate preferences for melanoma screening options compared with skin self-examination in adults considered to be at increased risk of developing skin cancer. A discrete choice experiment was completed by 35 consumers, all of whom had prior experience with the use of teledermoscopy, in Queensland, Australia. Participants made 12 choices between screening alternatives described by seven attributes including monetary cost. A mixed logit model was used to estimate the relative weights that consumers place on different aspects of screening, along with the marginal willingness to pay for teledermoscopy as opposed to screening at a clinic. Overall, participants preferred screening/diagnosis by a health professional rather than skin self-examination. Key drivers of screening choice were for results to be reviewed by a dermatologist; a higher detection rate; fewer non-cancerous moles being removed in relation to every skin cancer detected; and less time spent away from usual activities. On average, participants were willing to pay AUD110 to have teledermoscopy with dermatologist review available to them as a screening option. Consumers preferentially value aspects of care that are more feasible with a teledermoscopy screening model, as compared with other skin cancer screening and diagnosis options. This study adds to previous literature in the area which has relied on the use of consumer satisfaction scales to assess the acceptability of teledermoscopy. © The Author(s) 2015.

Estimating preferences for local public services using migration data.

PubMed

Dahlberg, Matz; Eklöf, Matias; Fredriksson, Peter; Jofre-Monseny, Jordi

2012-01-01

Using Swedish micro data, the paper examines the impact of local public services on community choice. The choice of community is modelled as a choice between a discrete set of alternatives. It is found that, given taxes, high spending on child care attracts migrants. Less conclusive results are obtained with respect to the role of spending on education and elderly care. High local taxes deter migrants. Relaxing the independence of the irrelevant alternatives assumption, by estimating a mixed logit model, has a significant impact on the results.

Dialysis modality preference of patients with CKD and family caregivers: a discrete-choice study.

PubMed

Morton, Rachael L; Snelling, Paul; Webster, Angela C; Rose, John; Masterson, Rosemary; Johnson, David W; Howard, Kirsten

2012-07-01

Dialysis modality preferences of patients with chronic kidney disease (CKD) and family caregivers are important, yet rarely quantified. Prospective, unlabeled, discrete-choice experiment with random-parameter logit analysis. Adults with stages 3-5 CKD and caregivers educated about dialysis treatment options from 8 Australian renal clinics. Preferences for and trade-offs between the dialysis treatment attributes of life expectancy, number of hospital visits per week, ability to travel, hours per treatment, treatment time of day, subsidized transport service, and flexibility of treatment schedule. Results presented as ORs for preferring home-based or in-center dialysis to conservative care. 105 predialysis patients and 73 family caregivers completed the study. Median patient age was 63 years, and mean estimated glomerular filtration rate was 18.1 (range, 6-34) mL/min/1.73 m(2). Median caregiver age was 61 years. Home-based dialysis (either peritoneal or home hemodialysis) was chosen by patients in 65% of choice sets; in-center dialysis, in 35%; and conservative care, in 10%. For caregivers, this was 72%, 25%, and 3%, respectively. Both patients and caregivers preferred longer rather than shorter hours of dialysis (ORs of 2.02 [95% CI, 1.51-2.70] and 2.67 [95% CI, 1.85-3.85] for patients and caregivers, respectively), but were less likely to choose nocturnal than daytime dialysis (ORs of 0.07 [95% CI, 0.01-0.75] and 0.03 [95% CI, 0.01-0.20]). Patients were willing to forgo 23 (95% CI, 19-27) months of life expectancy with home-based dialysis to decrease their travel restrictions. For caregivers, this was 17 (95% CI, 16-18) patient-months. Data were limited to stated preferences rather than actual choice of dialysis modality. Our study suggests that it is rare for caregivers to prefer conservative nondialytic care for family members with CKD. Home-based dialysis modalities that enable patients and their family members to travel with minimal restriction would be strongly aligned with the preferences of both parties. Copyright © 2012 National Kidney Foundation, Inc. All rights reserved.

A Bell-Curved Based Algorithm for Mixed Continuous and Discrete Structural Optimization

NASA Technical Reports Server (NTRS)

Kincaid, Rex K.; Weber, Michael; Sobieszczanski-Sobieski, Jaroslaw

2001-01-01

An evolutionary based strategy utilizing two normal distributions to generate children is developed to solve mixed integer nonlinear programming problems. This Bell-Curve Based (BCB) evolutionary algorithm is similar in spirit to (mu + mu) evolutionary strategies and evolutionary programs but with fewer parameters to adjust and no mechanism for self adaptation. First, a new version of BCB to solve purely discrete optimization problems is described and its performance tested against a tabu search code for an actuator placement problem. Next, the performance of a combined version of discrete and continuous BCB is tested on 2-dimensional shape problems and on a minimum weight hub design problem. In the latter case the discrete portion is the choice of the underlying beam shape (I, triangular, circular, rectangular, or U).

Learning may need only a few bits of synaptic precision

NASA Astrophysics Data System (ADS)

Baldassi, Carlo; Gerace, Federica; Lucibello, Carlo; Saglietti, Luca; Zecchina, Riccardo

2016-05-01

Learning in neural networks poses peculiar challenges when using discretized rather then continuous synaptic states. The choice of discrete synapses is motivated by biological reasoning and experiments, and possibly by hardware implementation considerations as well. In this paper we extend a previous large deviations analysis which unveiled the existence of peculiar dense regions in the space of synaptic states which accounts for the possibility of learning efficiently in networks with binary synapses. We extend the analysis to synapses with multiple states and generally more plausible biological features. The results clearly indicate that the overall qualitative picture is unchanged with respect to the binary case, and very robust to variation of the details of the model. We also provide quantitative results which suggest that the advantages of increasing the synaptic precision (i.e., the number of internal synaptic states) rapidly vanish after the first few bits, and therefore that, for practical applications, only few bits may be needed for near-optimal performance, consistent with recent biological findings. Finally, we demonstrate how the theoretical analysis can be exploited to design efficient algorithmic search strategies.

Using decision mapping to inform the development of a stated choice survey to elicit youth preferences for sexual and reproductive health and HIV services in rural Malawi.

PubMed

Michaels-Igbokwe, Christine; Lagarde, Mylene; Cairns, John; Terris-Prestholt, Fern

2014-03-01

The process of designing and developing discrete choice experiments (DCEs) is often under reported. The need to adequately report the results of qualitative work used to identify attributes and levels used in a DCE is recognised. However, one area that has received relatively little attention is the exploration of the choice question of interest. This paper provides a case study of the process used to design a stated preference survey to assess youth preferences for integrated sexual and reproductive health (SRH) and HIV outreach services in Malawi. Development and design consisted of six distinct but overlapping and iterative stages. Stage one was a review of the literature. Stage two involved developing a decision map to conceptualise the choice processes involved. Stage three included twelve focus group discussions with young people aged 15-24 (n = 113) and three key informant interviews (n = 3) conducted in Ntcheu District, Malawi. Stage four involved analysis of qualitative data and identification of potential attributes and levels. The choice format and experimental design were selected in stages five and six. The results of the literature review were used to develop a decision map outlining the choices that young people accessing SRH services may face. For youth that would like to use services two key choices were identified: the choice between providers and the choice of service delivery attributes within a provider type. Youth preferences for provider type are best explored using a DCE with a labelled design, while preferences for service delivery attributes associated with a particular provider are better understood using an unlabelled design. Consequently, two DCEs were adopted to jointly assess preferences in this context. Used in combination, the results of the literature review, the decision mapping process and the qualitative work provided robust approach to designing the DCEs individually and as complementary pieces of work. Copyright © 2014 Elsevier Ltd. All rights reserved.

Isogeometric Divergence-conforming B-splines for the Darcy-Stokes-Brinkman Equations

DTIC Science & Technology

2012-01-01

dimensionality ofQ0,h using T-splines [5]. However, a proof of mesh-independent discrete stability remains absent with this choice of pressure space ... the boundary ∂K +/− of element K+/−. With the above notation established, let us define the following bilinear form: a ∗h(w,v) = np∑ i=1 ( (2ν∇sw,∇sv...8.3 Two- Dimensional Problem with a Singular Solution To examine how our discretization performs in

Stated preferences for anti-malarial drug characteristics in Zomba, a malaria endemic area of Malawi

PubMed Central

2014-01-01

Background The evidence on determinants of individuals’ choices for anti-malarial drug treatments is scarce. This study sought to measure the strength of preference for adult antimalarial drug treatment attributes of heads of urban, rural and peri-urban households in a resource-limited malaria-endemic area of sub-Saharan Africa. Methods Discrete choice experiments were conducted with 508 heads of household interviewed face-to-face for a household population survey of health-seeking behavior in Zomba District, Malawi. The interviews were held in Chichewa and the choice experiment questions were presented with cartoon aids. The anti-malarial drug attributes included in the stated preference experiment were: speed of fever resolution, side effects (pruritus) risk, protection (duration of prophylactic effect), price, duration of treatment course and recommendation by a health professional. Sixteen treatment profiles from a fractional factorial design by orthogonal array were paired into choice scenarios, and scenarios were randomly assigned to participants so that each participant was presented with a series of eight pairwise choice scenarios. Respondents had the option to state indifference between the two profiles or decline to choose. Data were analysed in a mixed logit model, with normally distributed coefficients for all six attributes. Results The sex ratio was balanced in urban areas, whereas 63% of participants in rural areas were male. The proportion of individuals with no education was considerably higher in the rural group (25%) than in the urban (5%) and peri-urban (6%) groups. All attributes investigated had the expected influence, and traded-off in most respondents’ choices. There were heterogeneous effects of price, pruritus risk, treatment recommendation by a professional, and duration of prophylaxis across respondents, only partly explained by their differences in education, household per capita expenditure, sex and age. Individuals´ demand elasticity (simulated median, inter-quartile range) was highest (most responsive) to speed of symptom resolution (0.88, 0.80-0.89) and pruritus risk (0.25, 0.08-0.62). Conclusions Most adult antimalarial users are willing to use treatments without recommendation from health professional, and may be influenced by price. Future studies should investigate the magnitude of differences in price and treatment attribute sensitivity between adult anti-malarial drug users in rural, peri-urban and urban areas in order to determine optimal price subsidies. PMID:25005466

A spatial econometric analysis of land-use change with land cover trends data: an application to the Pacific Northwest

Treesearch

David J. Lewis; Ralph J. Alig

2014-01-01

This paper develops a plot-level spatial econometric land-use model and estimates it with U.S. Geological Survey Land Cover Trends (LCT) geographic information system panel data for the western halves of the states of Oregon and Washington. The discrete-choice framework we use models plot-scale choices of the three dominant land uses in this region: forest, agriculture...

Managing Minor Ailments; The Public’s Preferences for Attributes of Community Pharmacies. A Discrete Choice Experiment

PubMed Central

Ryan, Mandy; Bond, Christine; Watson, Margaret

2016-01-01

Background Demand for health services continues to rise. Greater use of community pharmacy services instead of medical services for minor ailments could help relieve pressure on healthcare providers in high-cost settings. Community pharmacies are recognised sources of treatment and advice for people wishing to manage these ailments. However, increasing the public’s use of pharmacy services may depend on attributes of pharmacies and their staff. This study aimed to determine the general public’s relative preferences for community pharmacy attributes using a discrete choice experiment (DCE). Method A UK-wide DCE survey of the general public was conducted using face-to-face computer-assisted personal interviews. Attributes and levels for the DCE were informed by a literature review and a cohort study of community pharmacy customers. The context for the experiment was a minor ailment scenario describing flu-like symptoms. The DCE choice sets described two hypothetical community pharmacy services; respondents were asked to choose which (if either) of the two pharmacies they would prefer to help them manage symptoms. Data from 1,049 interviews were analysed using an error components logit model. Willingness to pay (WTP), a monetary measure of benefit, was estimated for the different attribute levels. Results When seeking help or treatment for flu-like symptoms, respondents most valued a pharmacy service that would improve their understanding and management of symptoms (WTP = £6.28), provided by staff who are trained (WTP (pharmacist) = £2.63: WTP(trained assistant) = £3.22), friendly and approachable (WTP = £3.38). Waiting time, pharmacy location and availability of parking also contributed to respondents’ preferences. WTP for a service comprising the best possible combination of attributes and levels was calculated as £55.43. Conclusion Attributes of a community pharmacy and its staff may influence people’s decisions about which pharmacy they would visit to access treatment and advice for minor ailments. In line with the public’s preferences, offering community pharmacy services that help people to better understand and manage symptoms, are provided promptly by trained staff who are friendly and approachable, and in a local setting with easy access to parking, has the potential to increase uptake amongst those seeking help to manage minor ailments. In this way it may be possible to shift demand away from high-cost health services and make more efficient use of scarce public resources. PMID:27031588

What are colorectal cancer survivors' preferences for dietary advice? A best-worst discrete choice experiment.

PubMed

Wright, Stuart J; Gibson, Debbie; Eden, Martin; Lal, Simon; Todd, Chris; Ness, Andy; Burden, Sorrel

2017-12-01

Studies on healthy lifestyle interventions in survivors of colorectal cancer have been disappointing, demonstrating only modest changes. This study aims to quantify people's preferences for different aspects of dietary intervention. A best-worst discrete choice experiment was designed and incorporated into a questionnaire including participants' characteristics and a self-assessment of lifestyle. The response rate was 68% and 179 questionnaires were analysed. When analysing aggregate preferences, the modes of information provision selected as the most preferred were "face-to-face" (willingness to pay (WTP) £63.97, p ≤ 0.001) and "telephone" (WTP £62.36, p < 0.001) discussions whereas group discussions were preferred least (WTP -£118.96, p ≤ 0.001). Scenarios that included hospitals were most preferred (WTP £17.94, p = 0.031), and the favoured provider was bowel cancer nurses (WTP £75.11, p ≤ 0.001). When investigating preference heterogeneity, three sub-groups were identified: Firstly, "technophiles" preferring email (WTP £239.60, p ≤ 0.001) were male, were younger and had fewer risk factors. Secondly, a "one-to-one" group had strong preference for interventions over the telephone or at their local doctors and were older (WTP £642.13, p ≤ 0.001). Finally, a "person-centred" group preferred face-to-face individual or group sessions (WTP £358.79, p < 0.001) and had a high risk lifestyle. For survivors of colorectal cancer, there is not one approach that suits all when it comes to providing dietary advice. This is important information to consider when planning healthy lifestyle interventions which include dietary advice for survivors of colorectal cancer. Aligning services to individuals' preferences has the potential to improve patient experience and outcomes by increasing uptake of healthy lifestyle advice services and promoting a more tailored approach to dietary modifications, acknowledging sub-groups of people within the total population of colorectal cancer survivors.

Health worker preferences for community-based health insurance payment mechanisms: a discrete choice experiment

PubMed Central

2012-01-01

Background In 2004, a community-based health insurance scheme (CBI) was introduced in Nouna health district, Burkina Faso. Since its inception, coverage has remained low and dropout rates high. One important reason for low coverage and high dropout is that health workers do not support the CBI scheme because they are dissatisfied with the provider payment mechanism of the CBI. Methods A discrete choice experiment (DCE) was used to examine CBI provider payment attributes that influence health workers’ stated preferences for payment mechanisms. The DCE was conducted among 176 health workers employed at one of the 34 primary care facilities or the district hospital in Nouna health district. Conditional logit models with main effects and interactions terms were used for analysis. Results Reimbursement of service fees (adjusted odds ratio (aOR) 1.49, p < 0.001) and CBI contributions for medical supplies and equipment (aOR 1.47, p < 0.001) had the strongest effect on whether the health workers chose a given provider payment mechanism. The odds of selecting a payment mechanism decreased significantly if the mechanism included (i) results-based financing (RBF) payments made through the local health management team (instead of directly to the health workers (aOR 0.86, p < 0.001)) or (ii) RBF payments based on CBI coverage achieved in the health worker’s facility relative to the coverage achieved at other facilities (instead of payments based on the numbers of individuals or households enrolled at the health worker’s facility (aOR 0.86, p < 0.001)). Conclusions Provider payment mechanisms can crucially determine CBI performance. Based on the results from this DCE, revised CBI payment mechanisms were introduced in Nouna health district in January 2011, taking into consideration health worker preferences on how they are paid. PMID:22697498

Improving the public health sector in South Africa: eliciting public preferences using a discrete choice experiment.

PubMed

Honda, Ayako; Ryan, Mandy; van Niekerk, Robert; McIntyre, Diane

2015-06-01

The introduction of national health insurance (NHI), aimed at achieving universal coverage, is the most important issue currently on the South African health policy agenda. Improvement in public sector health-care provision is crucial for the successful implementation of NHI as, regardless of whether health-care services become more affordable and available, if the quality of the services provided is not acceptable, people will not use the services. Although there has been criticism of the quality of public sector health services, limited research is available to identify what communities regard as the greatest problems with the services. A discrete choice experiment (DCE) was undertaken to elicit public preferences on key dimensions of quality of care when selecting public health facilities in South Africa. Qualitative methods were applied to establish attributes and levels for the DCE. To elicit preferences, interviews with community members were held in two South African provinces: 491 in Western Cape and 499 in Eastern Cape. The availability of necessary medicine at health facilities has the greatest impact on the probability of attending public health facilities. Other clinical quality attributes (i.e. provision of expert advice and provision of a thorough examination) are more valued than non-clinical quality of care attributes (i.e. staff attitude, treatment by doctors or nurses, and waiting time). Treatment by a doctor was less valued than all other attributes. Communities are prepared to tolerate public sector health service characteristics such as a long waiting time, poor staff attitudes and lack of direct access to doctors if they receive the medicine they need, a thorough examination and a clear explanation of the diagnosis and prescribed treatment from health professionals. These findings prioritize issues that the South African government must address in order to meet their commitment to improve public sector health-care service provision. Published by Oxford University Press in association with The London School of Hygiene and Tropical Medicine © The Author 2014; all rights reserved.

Prescriber preferences for behavioural economics interventions to improve treatment of acute respiratory infections: a discrete choice experiment

PubMed Central

Gong, Cynthia L; Hay, Joel W; Meeker, Daniella; Doctor, Jason N

2016-01-01

Objective To elicit prescribers' preferences for behavioural economics interventions designed to reduce inappropriate antibiotic prescribing, and compare these to actual behaviour. Design Discrete choice experiment (DCE). Setting 47 primary care centres in Boston and Los Angeles. Participants 234 primary care providers, with an average 20 years of practice. Main outcomes and measures Results of a behavioural economic intervention trial were compared to prescribers' stated preferences for the same interventions relative to monetary and time rewards for improved prescribing outcomes. In the randomised controlled trial (RCT) component, the 3 computerised prescription order entry-triggered interventions studied included: Suggested Alternatives (SA), an alert that populated non-antibiotic treatment options if an inappropriate antibiotic was prescribed; Accountable Justifications (JA), which prompted the prescriber to enter a justification for an inappropriately prescribed antibiotic that would then be documented in the patient's chart; and Peer Comparison (PC), an email periodically sent to each prescriber comparing his/her antibiotic prescribing rate with those who had the lowest rates of inappropriate antibiotic prescribing. A DCE study component was administered to determine whether prescribers felt SA, JA, PC, pay-for-performance or additional clinic time would most effectively reduce their inappropriate antibiotic prescribing. Willingness-to-pay (WTP) was calculated for each intervention. Results In the RCT, PC and JA were found to be the most effective interventions to reduce inappropriate antibiotic prescribing, whereas SA was not significantly different from controls. In the DCE however, regardless of treatment intervention received during the RCT, prescribers overwhelmingly preferred SA, followed by PC, then JA. WTP estimates indicated that each intervention would be significantly cheaper to implement than pay-for-performance incentives of $200/month. Conclusions Prescribing behaviour and stated preferences are not concordant, suggesting that relying on stated preferences alone to inform intervention design may eliminate effective interventions. Trial registration number NCT01454947; Results. PMID:27660322

Societal Preferences for Funding Orphan Drugs in the United Kingdom: An Application of Person Trade-Off and Discrete Choice Experiment Methods.

PubMed

Bourke, Siobhan M; Plumpton, Catrin O; Hughes, Dyfrig A

2018-05-01

It is unclear whether UK National Health Service (NHS) policies for orphan drugs, which permit funding of non-cost-effective treatments, reflect societal preferences. We conducted person trade-off (PTO) and discrete choice experiment (DCE) among 3950 adults selected to be representative of the UK general population. Experimental design was informed by surveys of patients affected by rare diseases, their caregivers, health care staff, and policymakers. Societal preferences were estimated in relation to treating a common disease, increases in waiting lists, or filling of vacant NHS posts. Results of the DCE were applied to recently licensed orphan drugs. On the basis of equal cost, the majority of respondents to the PTO (54%; 95% confidence interval [CI] 50-59) chose to allocate funds equally between patients treated for rare diseases and those treated for common diseases, with 32% (95% CI 28-36) favoring treating rare diseases over treating common diseases (14%; 95% CI 11-17), which this reduced to 23% (95% CI 20-27) when rare disease treatments were 10 times more expensive. When framed differently, more respondents prioritized not increasing waiting list size (43%; 95% CI 39-48) than to treat rare disease patients (34%; 95% CI 30-38). The DCE indicated a greater preference for treating a common disease over a rare disease. Respondents agreed with five of 12 positive appraisal recommendations for orphan drugs, even if their list price was higher, but preferred the NHS not to fund the remainder. The general public does not value rarity as a sufficient reason to justify special consideration for additional NHS funding of orphan drugs. This has implications regarding the appropriateness of operating higher thresholds of cost-effectiveness. Copyright © 2018 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Therapy preferences of patients with lung and colon cancer: a discrete choice experiment.

PubMed

Schmidt, Katharina; Damm, Kathrin; Vogel, Arndt; Golpon, Heiko; Manns, Michael P; Welte, Tobias; Graf von der Schulenburg, J-Matthias

2017-01-01

There is increasing interest in studies that examine patient preferences to measure health-related outcomes. Understanding patients' preferences can improve the treatment process and is particularly relevant for oncology. In this study, we aimed to identify the subgroup-specific treatment preferences of German patients with lung cancer (LC) or colorectal cancer (CRC). Six discrete choice experiment (DCE) attributes were established on the basis of a systematic literature review and qualitative interviews. The DCE analyses comprised generalized linear mixed-effects model and latent class mixed logit model. The study cohort comprised 310 patients (194 with LC, 108 with CRC, 8 with both types of cancer) with a median age of 63 (SD =10.66) years. The generalized linear mixed-effects model showed a significant ( P <0.05) degree of association for all of the tested attributes. "Strongly increased life expectancy" was the attribute given the greatest weight by all patient groups. Using latent class mixed logit model analysis, we identified three classes of patients. Patients who were better informed tended to prefer a more balanced relationship between length and health-related quality of life (HRQoL) than those who were less informed. Class 2 (LC patients with low HRQoL who had undergone surgery) gave a very strong weighting to increased length of life. We deduced from Class 3 patients that those with a relatively good life expectancy (CRC compared with LC) gave a greater weight to moderate effects on HRQoL than to a longer life. Overall survival was the most important attribute of therapy for patients with LC or CRC. Differences in treatment preferences between subgroups should be considered in regard to treatment and development of guidelines. Patients' preferences were not affected by sex or age, but were affected by the cancer type, HRQoL, surgery status, and the main source of information on the disease.

Adolescent values for immunisation programs in Australia: A discrete choice experiment.

PubMed

Wang, Bing; Chen, Gang; Ratcliffe, Julie; Afzali, Hossein Haji Ali; Giles, Lynne; Marshall, Helen

2017-01-01

The importance of adolescent engagement in health decisions and public health programs such as immunisation is becoming increasingly recognised. Understanding adolescent preferences and further identifying barriers and facilitators for immunisation acceptance is critical to the success of adolescent immunisation programs. This study applied a discrete choice experiment (DCE) to assess vaccination preferences in adolescents. This study was conducted as a cross-sectional, national online survey in Australian adolescents. The DCE survey evaluated adolescent vaccination preferences. Six attributes were assessed including disease severity, target for protection, price, location of vaccination provision, potential side effects and vaccine delivery method. A mixed logit model was used to analyse DCE data. This survey was conducted between December 2014 and January 2015. Of 800 adolescents aged 15 to 19 years, stronger preferences were observed overall for: vaccination in the case of a life threatening illness (p<0.001), lower price vaccinations (p<0.001), mild but common side effects (p = 0.004), delivery via a skin patch (p<0.001) and being administered by a family practitioner (p<0.001). Participants suggested that they and their families would be willing to pay AU$394.28 (95%CI: AU$348.40 to AU$446.92) more for a vaccine targeting a life threatening illness than a mild-moderate illness, AU$37.94 (95%CI: AU$19.22 to AU$57.39) more for being vaccinated at a family practitioner clinic than a council immunisation clinic, AU$23.01 (95%CI: AU$7.12 to AU$39.24) more for common but mild and resolving side effects compared to rare but serious side effects, and AU$51.80 (95%CI: AU$30.42 to AU$73.70) more for delivery via a skin patch than injection. Consideration of adolescent preferences may result in improved acceptance of, engagement in and uptake of immunisation programs targeted for this age group.

Identifying Societal Preferences for River Restoration in a Densely Populated Urban Environment: Evidence from a Discrete Choice Experiment in Central Brussels

NASA Astrophysics Data System (ADS)

Chen, Wendy Y.; Liekens, Inge; Broekx, Steven

2017-08-01

One of the major challenges facing river restoration in densely populated urban areas has been the disparity between the expectations of policy-makers and societal preferences. This study aimed to elicit public preferences and elucidate underlying sources of preference heterogeneity, using the Zenne River in central Brussels, Belgium, as a case study. A discrete choice experiment was administered to a representative sample of the Brussels population. Five attributes were specified, including water quality, ecological status, hydromorphological features of channels, recreational opportunities, and monetary cost. Our econometric analysis based on mixed logit models revealed that overall public would like to have a more natural river (open and naturalized channel, good water quality, and with rich species diversity), while achieving good water quality was the most preferred attribute. Respondents categorized as male, non-Belgian citizen, or not being a member of an environmental organization constituted an inclination to prefer the status quo. Belgian citizens showed a pronounced preference for good biodiversity, and being a member of an environmental organization could moderate the strong preference for good water quality. This study provided insights into the relative attractiveness of key attributes pertaining to river restoration, in general, and served as a useful input to the ongoing discussion concerning the future plan for the Zenne River in Brussels, specifically. Possible implications also exist for other urban river restorations in the rest of Europe, where the Water Framework Directive has become a major impetus for the expansion of freshwater ecosystem restoration from rural and peri-urban areas to densely populated urban areas. Particularly, the cultural heterogeneity of societal preferences should be tested and accounted for to compare the welfare impacts of river restoration and to facilitate benefit transfer, within and between river basins, in the Water Framework Directive implementation.

The effects of convenience and quality on the demand for vaccination: Results from a discrete choice experiment.

PubMed

Guo, Na; Zhang, Guojie; Zhu, Dawei; Wang, Jian; Shi, Luwen

2017-05-15

Vaccination is an effective way to prevent infectious diseases. Most studies analysed people's vaccine decisions, but few studies have analysed the effects of convenience such as immunisation schedule and distance and the quality of vaccination service on vaccination uptake. The aim of this paper was to investigate adults' preferences for convenience and quality of vaccination service, calculate the private economic benefit from convenience (vaccination schedule and distance) and quality, and predict the uptake rate for different vaccine scenarios. In our study, we interviewed 266 adults in 2 counties of Shandong province in China. The discrete choice experiment (DCE) was employed to analyse the preference for hepatitis B virus (HBV) vaccination, and a mixed logit model was used to estimate respondent preferences for vaccination attributes included in the DCE. The protection rate against hepatitis B (HB), duration of protection, risk of side effects, vaccination cost, schedule, and vaccination sites were proved to influence adults' preferences for HBV vaccination. The estimated willingness to pay (WTP) for 1 dose schedule instead of 3 doses and for a third-level vaccination site instead of a first-level site was almost equal (19 RMB). However, if the protection duration of the vaccination programme changed from 5years to 20years, the adults were willing to pay 35.05 RMB, and WTP for a 99% protection rate instead of a 79% rate was 67.71 RMB. The predicted uptake rate is almost 43% for the base case of HBV vaccination. Adults made trade-offs between vaccination schedules, vaccination sites, and other characteristics of HBV vaccine. The impact of attributes of the vaccine itself, especially protection rate against HB, duration of protection, and risk of side-effects, is more dramatic than convenience and quality of vaccination service. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Patient and nurse preferences for nurse handover-using preferences to inform policy: a discrete choice experiment protocol.

PubMed

Spinks, Jean; Chaboyer, Wendy; Bucknall, Tracey; Tobiano, Georgia; Whitty, Jennifer A

2015-11-11

Nursing bedside handover in hospital has been identified as an opportunity to involve patients and promote patient-centred care. It is important to consider the preferences of both patients and nurses when implementing bedside handover to maximise the successful uptake of this policy. We outline a study which aims to (1) identify, compare and contrast the preferences for various aspects of handover common to nurses and patients while accounting for other factors, such as the time constraints of nurses that may influence these preferences.; (2) identify opportunities for nurses to better involve patients in bedside handover and (3) identify patient and nurse preferences that may challenge the full implementation of bedside handover in the acute medical setting. We outline the protocol for a discrete choice experiment (DCE) which uses a survey design common to both patients and nurses. We describe the qualitative and pilot work undertaken to design the DCE. We use a D-efficient design which is informed by prior coefficients collected during the pilot phase. We also discuss the face-to-face administration of this survey in a population of acutely unwell, hospitalised patients and describe how data collection challenges have been informed by our pilot phase. Mixed multinomial logit regression analysis will be used to estimate the final results. This study has been approved by a university ethics committee as well as two participating hospital ethics committees. Results will be used within a knowledge translation framework to inform any strategies that can be used by nursing staff to improve the uptake of bedside handover. Results will also be disseminated via peer-reviewed journal articles and will be presented at national and international conferences. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Quantifying parental preferences for interventions designed to improve home food preparation and home food environments during early childhood.

PubMed

Virudachalam, Senbagam; Chung, Paul J; Faerber, Jennifer A; Pian, Timothy M; Thomas, Karen; Feudtner, Chris

2016-03-01

Though preparing healthy food at home is a critical health promotion habit, few interventions have aimed to improve parental cooking skills and behaviors. We sought to understand parents' preferences and priorities regarding interventions to improve home food preparation practices and home food environments during early childhood. We administered a discrete choice experiment using maximum difference scaling. Eighty English-speaking parents of healthy 1-4 year-old children rated the relative importance of potential attributes of interventions to improve home food preparation practices and home food environments. We performed latent class analysis to identify subgroups of parents with similar preferences and tested for differences between the subgroups. Participants were mostly white or black 21-45 year-old women whose prevalence of overweight/obesity mirrored the general population. Latent class analysis revealed three distinct groups of parental preferences for intervention content: a healthy cooking group, focused on nutrition and cooking healthier food; a child persuasion group, focused on convincing toddlers to eat home-cooked food; and a creative cooking group, focused on cooking without recipes, meal planning, and time-saving strategies. Younger, lower income, 1-parent households comprised the healthy cooking group, while older, higher income, 2-parent households comprised the creative cooking group (p < 0.05). The child persuasion group was more varied with regard to age, income, and household structure but cooked dinner regularly, unlike the other two groups (p < 0.05). Discrete choice experiments using maximum difference scaling can be employed to design and tailor interventions to change health behaviors. Segmenting a diverse target population by needs and preferences enables the tailoring and optimization of future interventions to improve parental home food preparation practices. Such interventions are important for creating healthier home food environments and preventing obesity starting from early childhood. Copyright © 2015 Elsevier Ltd. All rights reserved.

Acceptance of Vaccinations in Pandemic Outbreaks: A Discrete Choice Experiment

PubMed Central

Determann, Domino; Korfage, Ida J.; Lambooij, Mattijs S.; Bliemer, Michiel; Richardus, Jan Hendrik; Steyerberg, Ewout W.; de Bekker-Grob, Esther W.

2014-01-01

Background Preventive measures are essential to limit the spread of new viruses; their uptake is key to their success. However, the vaccination uptake in pandemic outbreaks is often low. We aim to elicit how disease and vaccination characteristics determine preferences of the general public for new pandemic vaccinations. Methods In an internet-based discrete choice experiment (DCE) a representative sample of 536 participants (49% participation rate) from the Dutch population was asked for their preference for vaccination programs in hypothetical communicable disease outbreaks. We used scenarios based on two disease characteristics (susceptibility to and severity of the disease) and five vaccination program characteristics (effectiveness, safety, advice regarding vaccination, media attention, and out-of-pocket costs). The DCE design was based on a literature review, expert interviews and focus group discussions. A panel latent class logit model was used to estimate which trade-offs individuals were willing to make. Results All above mentioned characteristics proved to influence respondents’ preferences for vaccination. Preference heterogeneity was substantial. Females who stated that they were never in favor of vaccination made different trade-offs than males who stated that they were (possibly) willing to get vaccinated. As expected, respondents preferred and were willing to pay more for more effective vaccines, especially if the outbreak was more serious (€6–€39 for a 10% more effective vaccine). Changes in effectiveness, out-of-pocket costs and in the body that advises the vaccine all substantially influenced the predicted uptake. Conclusions We conclude that various disease and vaccination program characteristics influence respondents’ preferences for pandemic vaccination programs. Agencies responsible for preventive measures during pandemics can use the knowledge that out-of-pocket costs and the way advice is given affect vaccination uptake to improve their plans for future pandemic outbreaks. The preference heterogeneity shows that information regarding vaccination needs to be targeted differently depending on gender and willingness to get vaccinated. PMID:25057914

Preferences for long-term care services: willingness to pay estimates derived from a discrete choice experiment.

PubMed

Nieboer, Anna P; Koolman, Xander; Stolk, Elly A

2010-05-01

Ageing populations increase pressure on long-term care. Optimal resource allocation requires an optimal mix of care services based on costs and benefits. Contrary to costs, benefits remain largely unknown. This study elicits preferences in the general elderly population for long-term care services for varying types of patients. A discrete choice experiment was conducted in a general population subsample aged 50-65 years (N = 1082) drawn from the Dutch Survey Sampling International panel. To ascertain relative preferences for long-term care and willingness to pay for these, participants were asked to choose the best of two care scenarios for four groups of hypothetical patients: frail and demented elderly, with and without partner. The scenarios described long-term care using ten attributes based on Social Production Function theory: hours of care, organized social activities, transportation, living situation, same person delivering care, room for individual preferences, coordination of services, punctuality, time on waiting list, and co-payments. We found the greatest value was attached to same person delivering care and transportation services. Low value was attached to punctuality and room for individual preferences. Nursing homes were generally considered to be detrimental for well-being except for dementia patients without a partner. Overall, long-term care services were thought to produce greatest well-being for the patients 'without a partner' and those 'with dementia'. Individuals combining these two risk factors would benefit the most from all services except transportation which was considered more important for the frail elderly. The results support the notion that long-term care services represent different value for different types of patients and that the value of a service depends upon the social context. Examination of patient profiles confirmed the notion that physical, mental and social vulnerability affect valuation of the services. Policy-making would profit from allocation models in which budgetary requirements of different services can be balanced against the well-being they produce for individuals. Copyright 2010 Elsevier Ltd. All rights reserved.

Acceptance of vaccinations in pandemic outbreaks: a discrete choice experiment.

PubMed

Determann, Domino; Korfage, Ida J; Lambooij, Mattijs S; Bliemer, Michiel; Richardus, Jan Hendrik; Steyerberg, Ewout W; de Bekker-Grob, Esther W

2014-01-01

Preventive measures are essential to limit the spread of new viruses; their uptake is key to their success. However, the vaccination uptake in pandemic outbreaks is often low. We aim to elicit how disease and vaccination characteristics determine preferences of the general public for new pandemic vaccinations. In an internet-based discrete choice experiment (DCE) a representative sample of 536 participants (49% participation rate) from the Dutch population was asked for their preference for vaccination programs in hypothetical communicable disease outbreaks. We used scenarios based on two disease characteristics (susceptibility to and severity of the disease) and five vaccination program characteristics (effectiveness, safety, advice regarding vaccination, media attention, and out-of-pocket costs). The DCE design was based on a literature review, expert interviews and focus group discussions. A panel latent class logit model was used to estimate which trade-offs individuals were willing to make. All above mentioned characteristics proved to influence respondents' preferences for vaccination. Preference heterogeneity was substantial. Females who stated that they were never in favor of vaccination made different trade-offs than males who stated that they were (possibly) willing to get vaccinated. As expected, respondents preferred and were willing to pay more for more effective vaccines, especially if the outbreak was more serious (€6-€39 for a 10% more effective vaccine). Changes in effectiveness, out-of-pocket costs and in the body that advises the vaccine all substantially influenced the predicted uptake. We conclude that various disease and vaccination program characteristics influence respondents' preferences for pandemic vaccination programs. Agencies responsible for preventive measures during pandemics can use the knowledge that out-of-pocket costs and the way advice is given affect vaccination uptake to improve their plans for future pandemic outbreaks. The preference heterogeneity shows that information regarding vaccination needs to be targeted differently depending on gender and willingness to get vaccinated.

Identifying Societal Preferences for River Restoration in a Densely Populated Urban Environment: Evidence from a Discrete Choice Experiment in Central Brussels.

PubMed

Chen, Wendy Y; Liekens, Inge; Broekx, Steven

2017-08-01

One of the major challenges facing river restoration in densely populated urban areas has been the disparity between the expectations of policy-makers and societal preferences. This study aimed to elicit public preferences and elucidate underlying sources of preference heterogeneity, using the Zenne River in central Brussels, Belgium, as a case study. A discrete choice experiment was administered to a representative sample of the Brussels population. Five attributes were specified, including water quality, ecological status, hydromorphological features of channels, recreational opportunities, and monetary cost. Our econometric analysis based on mixed logit models revealed that overall public would like to have a more natural river (open and naturalized channel, good water quality, and with rich species diversity), while achieving good water quality was the most preferred attribute. Respondents categorized as male, non-Belgian citizen, or not being a member of an environmental organization constituted an inclination to prefer the status quo. Belgian citizens showed a pronounced preference for good biodiversity, and being a member of an environmental organization could moderate the strong preference for good water quality. This study provided insights into the relative attractiveness of key attributes pertaining to river restoration, in general, and served as a useful input to the ongoing discussion concerning the future plan for the Zenne River in Brussels, specifically. Possible implications also exist for other urban river restorations in the rest of Europe, where the Water Framework Directive has become a major impetus for the expansion of freshwater ecosystem restoration from rural and peri-urban areas to densely populated urban areas. Particularly, the cultural heterogeneity of societal preferences should be tested and accounted for to compare the welfare impacts of river restoration and to facilitate benefit transfer, within and between river basins, in the Water Framework Directive implementation.

Stated Preferences of Doctors for Choosing a Job in Rural Areas of Peru: A Discrete Choice Experiment

PubMed Central

Miranda, J. Jaime; Diez-Canseco, Francisco; Lema, Claudia; Lescano, Andrés G.; Lagarde, Mylene; Blaauw, Duane; Huicho, Luis

2012-01-01

Background Doctors’ scarcity in rural areas remains a serious problem in Latin America and Peru. Few studies have explored job preferences of doctors working in underserved areas. We aimed to investigate doctors’ stated preferences for rural jobs. Methods and Findings A labelled discrete choice experiment (DCE) was performed in Ayacucho, an underserved department of Peru. Preferences were assessed for three locations: rural community, Ayacucho city (Ayacucho’s capital) and other provincial capital city. Policy simulations were run to assess the effect of job attributes on uptake of a rural post. Multiple conditional logistic regressions were used to assess the relative importance of job attributes and of individual characteristics. A total of 102 doctors participated. They were five times more likely to choose a job post in Ayacucho city over a rural community (OR 4.97, 95%CI 1.2; 20.54). Salary increases and bonus points for specialization acted as incentives to choose a rural area, while increase in the number of years needed to get a permanent post acted as a disincentive. Being male and working in a hospital reduced considerably chances of choosing a rural job, while not living with a partner increased them. Policy simulations showed that a package of 75% salary increase, getting a permanent contract after two years in rural settings, and getting bonus points for further specialisation increased rural job uptake from 21% to 77%. A package of 50% salary increase plus bonus points for further specialisation would also increase the rural uptake from 21% to 52%. Conclusions Doctors are five times more likely to favour a job in urban areas over rural settings. This strong preference needs to be overcome by future policies aimed at improving the scarcity of rural doctors. Some incentives, alone or combined, seem feasible and sustainable, whilst others may pose a high fiscal burden. PMID:23272065

Type 2 diabetes patients’ preferences and willingness to pay for lifestyle programs: a discrete choice experiment

PubMed Central

2013-01-01

Background Participation rates of lifestyle programs among type 2 diabetes mellitus (T2DM) patients are less than optimal around the globe. Whereas research shows notable delays in the development of the disease among lifestyle program participants. Very little is known about the relative importance of barriers for participation as well as the willingness of T2DM patients to pay for participation in such programs. The aim of this study was to identify the preferences of T2DM patients with regard to lifestyle programs and to calculate participants’ willingness to pay (WTP) as well as to estimate the potential participation rates of lifestyle programs. Methods A Discrete Choice Experiment (DCE) questionnaire assessing five different lifestyle program attributes was distributed among 1250 Dutch adults aged 35–65 years with T2DM, 391 questionnaires (31%) were returned and included in the analysis. The relative importance of the program attributes (i.e., meal plan, physical activity (PA) schedule, consultation structure, expected program outcome and out-of-pocket costs) was determined using panel-mixed logit models. Based on the retrieved attribute estimates, patients’ WTP and potential participation rates were determined. Results The out-of-pocket costs (β = −0.75, P < .001), consultation structure (β = −0.46, P < .001) and expected outcome (β = 0.72, P < .001) were the most important factors for respondents when deciding whether to participate in a lifestyle program. Respondents were willing to pay €128 per year for individual instead of group consultation and €97 per year for 10 kilograms anticipated weight loss. Potential participation rates for different lifestyle-program scenarios ranged between 48.5% and 62.4%. Conclusions When deciding whether to participate in a lifestyle program, T2DM patients are mostly driven by low levels of out-of-pocket costs. Thereafter, they prefer individual consultation and high levels of anticipated outcomes with respect to weight loss. PMID:24289831

An exploration of parents' preferences for foot care in juvenile idiopathic arthritis: a possible role for the discrete choice experiment.

PubMed

Hendry, Gordon J; Turner, Debbie E; Gardner-Medwin, Janet; Lorgelly, Paula K; Woodburn, James

2014-02-06

An increased awareness of patients' and parents' care preferences regarding foot care is desirable from a clinical perspective as such information may be utilised to optimise care delivery. The aim of this study was to examine parents' preferences for, and valuations of foot care and foot-related outcomes in juvenile idiopathic arthritis (JIA). A discrete choice experiment (DCE) incorporating willingness-to-pay (WTP) questions was conducted by surveying 42 parents of children with JIA who were enrolled in a randomised-controlled trial of multidisciplinary foot care at a single UK paediatric rheumatology outpatients department. Attributes explored were: levels of pain; mobility; ability to perform activities of daily living (ADL); waiting time; referral route; and footwear. The DCE was administered at trial baseline. DCE data were analysed using a multinomial-logit-regression model to estimate preferences and relative importance of attributes of foot care. A stated-preference WTP question was presented to estimate parents' monetary valuation of health and service improvements. Every attribute in the DCE was statistically significant (p < 0.01) except that of cost (p = 0.118), suggesting that all attributes, except cost, have an impact on parents' preferences for foot care for their child. The magnitudes of the coefficients indicate that the strength of preference for each attribute was (in descending order): improved ability to perform ADL, reductions in foot pain, improved mobility, improved ability to wear desired footwear, multidisciplinary foot care route, and reduced waiting time. Parents' estimated mean annual WTP for a multidisciplinary foot care service was £1,119.05. In terms of foot care service provision for children with JIA, parents appear to prefer improvements in health outcomes over non-health outcomes and service process attributes. Cost was relatively less important than other attributes suggesting that it does not appear to impact on parents' preferences.

Application of discrete choice experiments to enhance stakeholder engagement as a strategy for advancing implementation: a systematic review.

PubMed

Salloum, Ramzi G; Shenkman, Elizabeth A; Louviere, Jordan J; Chambers, David A

2017-11-23

One of the key strategies to successful implementation of effective health-related interventions is targeting improvements in stakeholder engagement. The discrete choice experiment (DCE) is a stated preference technique for eliciting individual preferences over hypothetical alternative scenarios that is increasingly being used in health-related applications. DCEs are a dynamic approach to systematically measure health preferences which can be applied in enhancing stakeholder engagement. However, a knowledge gap exists in characterizing the extent to which DCEs are used in implementation science. We conducted a systematic literature search (up to December 2016) of the English literature to identify and describe the use of DCEs in engaging stakeholders as an implementation strategy. We searched the following electronic databases: MEDLINE, Econlit, PsychINFO, and the CINAHL using mesh terms. Studies were categorized according to application type, stakeholder(s), healthcare setting, and implementation outcome. Seventy-five publications were selected for analysis in this systematic review. Studies were categorized by application type: (1) characterizing demand for therapies and treatment technologies (n = 32), (2) comparing implementation strategies (n = 22), (3) incentivizing workforce participation (n = 11), and (4) prioritizing interventions (n = 10). Stakeholders included providers (n = 27), patients (n = 25), caregivers (n = 5), and administrators (n = 2). The remaining studies (n = 16) engaged multiple stakeholders (i.e., combination of patients, caregivers, providers, and/or administrators). The following implementation outcomes were discussed: acceptability (n = 75), appropriateness (n = 34), adoption (n = 19), feasibility (n = 16), and fidelity (n = 3). The number of DCE studies engaging stakeholders as an implementation strategy has been increasing over the past decade. As DCEs are more widely used as a healthcare assessment tool, there is a wide range of applications for them in stakeholder engagement. The DCE approach could serve as a tool for engaging stakeholders in implementation science.

Analysis of farmers' willingness to participate in pasture grazing programs: Results from a discrete choice experiment with German dairy farmers.

PubMed

Danne, M; Musshoff, O

2017-09-01

Over the last decades, the usage of pasture for grazing of dairy cows has decreased considerably. Pasture grazing programs initiated by dairy companies try to counteract this trend. The present paper investigates farmers' willingness to participate in such grazing programs. A special aim was to quantify the price premiums farmers require for program participation and to identify determinants influencing the premium level. The empirical analysis is based on a discrete choice experiment with 293 German dairy farmers. Models are estimated in terms of willingness to accept. It was found that farmers have no substantial preference for whether the pasture grazing program is financed by the food industry, a governmental scheme, or the dairy company. However, an extension of the annual or daily grazing period results in a decreasing willingness of farmers to participate in a pasture grazing program. In addition, farmers decline the option of a feeding standard prescribing the use of only green fodder when offered an alternative program that merely reduces the amount of concentrated feed or maize silage in the diet. Farmers' with an aversion toward program participation have a significant higher price demand for fulfilling the program requirements. Furthermore, the required price premiums increase with growing milk yields and a greater number of cows kept on the farm. However, if the availability of pasture is high, farmers are more likely to participate. The estimated price premiums and factors influencing farmers' willingness to participate found by this study should be considered by dairies and policymakers to gain insights into the design of possible pasture grazing programs from the perspective of farmers. Thereby, paying price premiums to farmers may increase the attractiveness of pasture grazing, which could finally result in an extended usage of pasture grazing. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Patient and Oncology Nurse Preferences for the Treatment Options in Advanced Melanoma: A Discrete Choice Experiment.

PubMed

Liu, Frank Xiaoqing; Witt, Edward A; Ebbinghaus, Scot; DiBonaventura Beyer, Grace; Basurto, Enrique; Joseph, Richard W

2017-10-25

Understanding the perceptions of patients and oncology nurses about the relative importance of benefits and risks associated with newer treatments of advanced melanoma can help to inform clinical decision-making. The aims of this study were to quantify and compare the views of patients and oncology nurses regarding the importance of attributes of treatments of advanced melanoma. A discrete choice experiment (DCE) was conducted in US-based oncology nurses and patients diagnosed with advanced melanoma. Patients and nurses were enlisted through online panels. In a series of scenarios, respondents had to choose between 2 hypothetical treatments, each with 7 attributes: mode of administration (MoA), dosing schedule (DS), median duration of therapy (DoT), objective response rate (ORR), progression-free survival (PFS), overall survival (OS), and grade 3 or 4 adverse events (AEs). Hierarchical Bayesian logistic regression models were used to estimate preference weights. A total of 200 patients with advanced melanoma and 150 oncology nurses participated. The relative importance estimates of attributes by patients and nurses, respectively, were as follows: OS, 33% and 28%; AEs, 29% and 26%; ORR, 25% and 27%; PFS, 12% and 15%; DS, 2% and 3%; DoT, 0% and 0%; and MoA, 0% and 0%. Both patients and oncology nurses valued OS, ORR, and AEs as the most important treatment attributes for advanced melanoma, followed by PFS, whereas DS, DoT, and MoA were given less value in their treatment decisions. Oncology nurses and patients have similar views on important treatment considerations for advanced melanoma, which can help build trust in shared decision-making.This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal.

What factors are critical to attracting NHS foundation doctors into specialty or core training? A discrete choice experiment

PubMed Central

Cleland, Jennifer; Johnston, Peter; Walker, Kim; Krucien, Nicolas; Skåtun, Diane

2018-01-01

Objectives Multiple personal and work-related factors influence medical trainees’ career decision-making. The relative value of these diverse factors is under-researched, yet this intelligence is crucially important for informing medical workforce planning and retention and recruitment policies. Our aim was to investigate the relative value of UK doctors’ preferences for different training post characteristics during the time period when they either apply for specialty or core training or take time out. Methods We developed a discrete choice experiment (DCE) specifically for this population. The DCE was distributed to all Foundation Programme Year 2 (F2) doctors across Scotland as part of the National Career Destination Survey in June 2016. The main outcome measure was the monetary value of training post characteristics, based on willingness to forgo additional potential income and willingness to accept extra income for a change in each job characteristic calculated from regression coefficients. Results 677/798 F2 doctors provided usable DCE responses. Location was the most influential characteristic of a training position, followed closely by supportive culture and then working conditions. F2 doctors would need to be compensated by an additional 45.75% above potential earnings to move from a post in a desirable location to one in an undesirable location. Doctors who applied for a training post placed less value on supportive culture and excellent working conditions than those who did not apply. Male F2s valued location and a supportive culture less than female F2s. Conclusion This is the first study focusing on the career decision-making of UK doctors at a critical careers decision-making point. Both location and specific job-related attributes are highly valued by F2 doctors when deciding their future. This intelligence can inform workforce policy to focus their efforts in terms of making training posts attractive to this group of doctors to enhance recruitment and retention. PMID:29530910

Understanding clinicians’ decisions to offer intravenous thrombolytic treatment to patients with acute ischaemic stroke: a protocol for a discrete choice experiment

PubMed Central

De Brún,, Aoife; Flynn, Darren; Joyce, Kerry; Ternent, Laura; Price, Christopher; Rodgers, Helen; Ford, Gary A; Lancsar, Emily; Rudd, Matthew; Thomson, Richard G

2014-01-01

Background Intravenous thrombolysis is an effective emergency treatment for acute ischaemic stroke for patients meeting specific criteria. Approximately 12% of eligible patients in England, Wales and Northern Ireland received thrombolysis in the first quarter of 2013, yet as many as 15% are eligible to receive treatment. Suboptimal use of thrombolysis may have been largely attributable to structural factors; however, with the widespread implementation of 24/7 hyper acute stroke services, continuing variation is likely to reflect differences in clinical decision-making, in particular the influence of ambiguous areas within the guidelines, licensing criteria and research evidence. Clinicians’ perceptions about thrombolysis may now exert a greater influence on treatment rates than structural/service factors. This research seeks to elucidate factors influencing thrombolysis decision-making by using patient vignettes to identify (1) patient-related and clinician-related factors that may help to explain variation in treatment and (2) associated trade-offs in decision-making based on the interplay of critical factors. Methods/analysis A discrete choice experiment (DCE) will be conducted to better understand how clinicians make decisions about whether or not to offer thrombolysis to patients with acute ischaemic stroke. To inform the design, exploratory work will be undertaken to ensure that (1) all potentially influential factors are considered for inclusion; and (2) to gain insights into the ‘grey areas’ of patient factors. A fractional factorial design will be used to combine levels of patient factors in vignettes, which will be presented to clinicians to allow estimation of the variable effects on decisions to offer thrombolysis. Ethics and dissemination Ethical approval for this study was obtained from the Newcastle University Research Ethics Committee. The results will be disseminated in peer review publications and at national conferences. Findings will be translated into continuing professional development activities and will support implementation of a computerised decision aid for thrombolysis (COMPASS) in acute stroke care. PMID:25009137

Assessment of the societal and individual preferences for fertility treatment in Australia: study protocol for stated preference discrete choice experiments

PubMed Central

Donnolley, Natasha; Shanahan, Marian; Chambers, Georgina M

2018-01-01

Introduction In Australia, societal and individual preferences for funding fertility treatment remain largely unknown. This has resulted in a lack of evidence about willingness to pay (WTP) for fertility treatment by either the general population (the funders) or infertile individuals (who directly benefit). Using a stated preference discrete choice experiment (SPDCE) approach has been suggested as a more appropriate method to inform economic evaluations of fertility treatment. We outline the protocol for an ongoing study which aims to assess fertility treatment preferences of both the general population and infertile individuals, and indirectly estimate their WTP for fertility treatment. Methods and analysis Two separate but related SPDCEs will be conducted for two population samples—the general population and infertile individuals—to elicit preferences for fertility treatment to indirectly estimate WTP. We describe the qualitative work to be undertaken to design the SPDCEs. We will use D-efficient fractional experimental designs informed by prior coefficients from the pilot surveys. The mode of administration for the SPDCE is also discussed. The final results will be analysed using mixed logit or latent class model. Ethics and dissemination This study is being funded by the Australian National Health and Medical Research Council (NHMRC) project grant AP1104543 and has been approved by the University of New South Wales Human Research Ethics Committee (HEC 17255) and a fertility clinic’s ethics committee. Findings of the study will be disseminated in peer-reviewed journals and presented at various conferences. A lay summary of the results will be made publicly available on the University of New South Wales National Perinatal Epidemiology and Statistics Unit website. Our results will contribute to the development of an evidence-based policy framework for the provision of cost-effective and patient-centred fertility treatment in Australia. PMID:29444788

An exploration of parents’ preferences for foot care in juvenile idiopathic arthritis: a possible role for the discrete choice experiment

PubMed Central

2014-01-01

Background An increased awareness of patients’ and parents’ care preferences regarding foot care is desirable from a clinical perspective as such information may be utilised to optimise care delivery. The aim of this study was to examine parents’ preferences for, and valuations of foot care and foot-related outcomes in juvenile idiopathic arthritis (JIA). Methods A discrete choice experiment (DCE) incorporating willingness-to-pay (WTP) questions was conducted by surveying 42 parents of children with JIA who were enrolled in a randomised-controlled trial of multidisciplinary foot care at a single UK paediatric rheumatology outpatients department. Attributes explored were: levels of pain; mobility; ability to perform activities of daily living (ADL); waiting time; referral route; and footwear. The DCE was administered at trial baseline. DCE data were analysed using a multinomial-logit-regression model to estimate preferences and relative importance of attributes of foot care. A stated-preference WTP question was presented to estimate parents’ monetary valuation of health and service improvements. Results Every attribute in the DCE was statistically significant (p < 0.01) except that of cost (p = 0.118), suggesting that all attributes, except cost, have an impact on parents’ preferences for foot care for their child. The magnitudes of the coefficients indicate that the strength of preference for each attribute was (in descending order): improved ability to perform ADL, reductions in foot pain, improved mobility, improved ability to wear desired footwear, multidisciplinary foot care route, and reduced waiting time. Parents’ estimated mean annual WTP for a multidisciplinary foot care service was £1,119.05. Conclusions In terms of foot care service provision for children with JIA, parents appear to prefer improvements in health outcomes over non-health outcomes and service process attributes. Cost was relatively less important than other attributes suggesting that it does not appear to impact on parents’ preferences. PMID:24502508

Measuring the importance of health domains in psoriasis - discrete choice experiment versus rating scales.

PubMed

Gutknecht, Mandy; Schaarschmidt, Marthe-Lisa; Danner, Marion; Blome, Christine; Augustin, Matthias

2018-01-01

Psoriasis affects different aspects of health-related quality of life (eg, physical, psychological, and social impairments); these health domains can be of different importance for patients. The importance of domains can be measured with the Patient Benefit Index (PBI). This questionnaire weights the achievement of treatment goals by Likert scales (0, "not important at all" to 4, "very important") using the Patient Needs Questionnaire (PNQ). Treatment goals assessed with the PBI have been assigned to five health domains; the importance of each domain can be calculated as the average importance of the respective treatment goals. In this study, the PBI approach of deriving importance weights is contrasted to a discrete choice experiment (DCE), in order to determine the importance of health domains in psoriasis, and to find if the resulting weights will differ when derived from these two methods. Adult patients with psoriasis completed both questionnaires (PNQ, DCE). The PBI domains were used as attributes in the DCE with the levels "did not help at all", "helped moderately", and "helped a lot". Using DCE, "improving physical functioning" was the most important health domain, followed by "improving psychological well-being". Using PNQ, these domains were ranked in position two and three following "strengthening confidence in the therapy and in a possible healing". The latter was least important using DCE. The only agreement of ranking was shown in "reducing impairments due to therapy" (position four). "Improving social functioning" was ranked in position three (DCE) and five (PNQ). Health domains have different importance to patients with psoriasis. Using PNQ or DCE to determine the importance of domains results in markedly different rankings; both approaches can thus not be considered equivalent. However, in this study, importance was assessed at the domain level in DCE and at the single item level in PNQ, which may have added to the differences.

What do UK doctors in training value in a post? A discrete choice experiment.

PubMed

Cleland, Jennifer; Johnston, Peter; Watson, Verity; Krucien, Nicolas; Skåtun, Diane

2016-02-01

Many individual and job-related factors are known to influence medical careers decision making. Medical trainees' (residents) views of which characteristics of a training post are important to them have been extensively studied but how they trade-off these characteristics is under-researched. Such information is crucial for the development of effective policies to enhance recruitment and retention. Our aim was to investigate the strength of UK foundation doctors' and trainees' preferences for training post characteristics in terms of monetary value. We used an online questionnaire study incorporating a discrete choice experiment (DCE), distributed to foundation programme doctors and doctors in training across all specialty groups within three UK regions, in August-October 2013. The main outcome measures were monetary values for training-post characteristics, based on willingness to forgo and willingness to accept extra income for a change in each job characteristic, calculated from regression coefficients. The questionnaire was answered by 1323 trainees. Good working conditions were the most influential characteristics of a training position. Trainee doctors would need to be compensated by an additional 49.8% above the average earnings within their specialty to move from a post with good working conditions to one with poor working conditions. A training post with limited rather than good opportunities for one's spouse or partner would require compensation of 38.4% above the average earnings within their specialty. Trainees would require compensation of 30.8% above the average earnings within their specialty to move from a desirable to a less desirable locality. These preferences varied only to a limited extent according to individual characteristics. Trainees place most value on good working conditions, good opportunities for their partners and desirable geographical location when making career-related decisions. This intelligence can be used to develop alternative models of workforce planning or to develop information about job opportunities that address trainees' values. © 2016 John Wiley & Sons Ltd.

What do UK medical students value most in their careers? A discrete choice experiment.

PubMed

Cleland, Jennifer A; Johnston, Peter; Watson, Verity; Krucien, Nicolas; Skåtun, Diane

2017-08-01

Many individual- and job-related factors are known to influence medical careers decision making. Previous research has extensively studied medical trainees' (residents') and students' views of the factors that are important. However, how trainees and students trade off these factors at times of important careers-related decision making is under-researched. Information about trade-offs is crucial to the development of effective policies to enhance the recruitment and retention of junior doctors. Our aim was to investigate the strength of UK medical students' preferences for the characteristics of training posts in terms of monetary value. We distributed a paper questionnaire that included a discrete choice experiment (DCE) to final-year medical students in six diverse medical schools across the UK. The main outcome measure was the monetary value of training post characteristics, based on willingness to forgo and willingness to accept extra income for a change in each job characteristic calculated from regression coefficients. A total of 810 medical students answered the questionnaire. The presence of good working conditions was by far the most influential characteristic of a training position. Medical students consider that, as newly graduated doctors, they will require compensation of an additional 43.68% above average earnings to move from a post with excellent working conditions to one with poor working conditions. Female students value excellent working conditions more highly than male students, whereas older medical students value them less highly than younger students. Students on the point of completing medical school and starting postgraduate training value good working conditions significantly more than they value desirable geographical location, unit reputation, familiarity with the unit or opportunities for partners or spouses. This intelligence can be used to address the crisis in workforce staffing that has developed in the UK and opens up fruitful areas for future research across contexts and in terms of examining stated preferences versus actual career-related behaviour. © 2017 John Wiley & Sons Ltd and The Association for the Study of Medical Education.

Preferences for general practice jobs: a survey of principals and sessional GPs

PubMed Central

Wordsworth, Sarah; Skåtun, Diane; Scott, Anthony; French, Fiona

2004-01-01

Background: Many countries are experiencing recruitment and retention problems in general practice, particularly in rural areas. In the United Kingdom (UK), recent contractual changes aim to address general practitioner (GP) recruitment and retention difficulties. However, the evidence base for their impact is limited, and preference differences between principals and sessional GPs (previously called non-principals) are insufficiently explored. Aim: To elicit GP principals' and sessional GPs' preferences for alternative jobs in general practice, and to identify the most important work attributes. Design of study: A discrete choice experiment. Setting: National Health Service (NHS) general practices throughout Scotland. Method: A postal questionnaire was sent to 1862 principals and 712 sessional GPs. The questionnaire contained a discrete choice experiment to quantify GPs' preferences for different job attributes. Results: A response rate of 49% (904/1862) was achieved for principals and 54% (388/712) for sessional GPs. Of responders, most principals were male (60%), and sessional GPs female (75%), with the average age being 42 years. All GPs preferred a job with longer consultations, no increase in working hours, but an increase in earnings. A job with outside commitments (for example, a health board or hospital) was preferable; one with additional out-of-hours work was less preferable. Sessional GPs placed a lower value on consultation length, were less worried about hours of work, and a job offering sufficient continuing professional development was less important. Conclusion: The differences in preferences between principals and sessional GPs, and also between different personal characteristics, suggests that a general contract could fail to cater for all GPs. Recruitment and retention of GPs may improve if the least preferred aspects of their jobs are changed. However, the long-term success of contractual reform will require enhancement of the positive aspects of working, such as patient contact. PMID:15469673

The impact of front-of-pack marketing attributes versus nutrition and health information on parents' food choices.

PubMed

Georgina Russell, Catherine; Burke, Paul F; Waller, David S; Wei, Edward

2017-09-01

Front-of-pack attributes have the potential to affect parents' food choices on behalf of their children and form one avenue through which strategies to address the obesogenic environment can be developed. Previous work has focused on the isolated effects of nutrition and health information (e.g. labeling systems, health claims), and how parents trade off this information against co-occurring marketing features (e.g. product imagery, cartoons) is unclear. A Discrete Choice Experiment was utilized to understand how front-of-pack nutrition, health and marketing attributes, as well as pricing, influenced parents' choices of cereal for their child. Packages varied with respect to the two elements of the Australian Health Star Rating system (stars and nutrient facts panel), along with written claims, product visuals, additional visuals, and price. A total of 520 parents (53% male) with a child aged between five and eleven years were recruited via an online panel company and completed the survey. Product visuals, followed by star ratings, were found to be the most significant attributes in driving choice, while written claims and other visuals were the least significant. Use of the Health Star Rating (HSR) system and other features were related to the child's fussiness level and parents' concerns about their child's weight with parents of fussy children, in particular, being less influenced by the HSR star information and price. The findings suggest that front-of-pack health labeling systems can affect choice when parents trade this information off against marketing attributes, yet some marketing attributes can be more influential, and not all parents utilize this information in the same way. Copyright © 2017. Published by Elsevier Ltd.

What sort of follow-up services would Australian breast cancer survivors prefer if we could no longer offer long-term specialist-based care? A discrete choice experiment

PubMed Central

Bessen, T; Chen, G; Street, J; Eliott, J; Karnon, J; Keefe, D; Ratcliffe, J

2014-01-01

Background: Early diagnosis and improved treatment outcomes have increased breast cancer survival rates that, in turn, have led to increased numbers of women undergoing follow-up after completion of primary treatment. The current workload growth is unsustainable for breast cancer specialists who also provide care for women newly diagnosed or with a recurrence. Appropriate and acceptable follow-up care is important; yet, currently we know little about patient preferences. The aim of this study was to explore the preferences of Australian breast cancer survivors for alternative modes of delivery of follow-up services. Methods: A self-administered questionnaire (online or paper) was developed. The questionnaire contained a discrete choice experiment (DCE) designed to explore patient preferences with respect to provider, location, frequency and method of delivery of routine follow-up care in years 3, 4 and 5 after diagnosis, as well as the perceived value of ‘drop-in' clinics providing additional support. Participants were recruited throughout Australia over a 6-month period from May to October 2012. Preference scores and choice probabilities were used to rank the top 10 most preferred follow-up scenarios for respondents. Results: A total of 836 women participated in the study, of whom 722 (86.4%) completed the DCE. In the absence of specialist follow-up, the 10 most valued surveillance scenarios all included a Breast Physician as the provider of follow-up care. The most preferred scenario is a face-to-face local breast cancer follow-up clinic held every 6 months and led by a Breast Physician, where additional clinics focused on the side effects of treatment are also provided. Conclusion: Beyond the first 2 years from diagnosis, in the absence of a specialist led follow-up, women prefer to have their routine breast cancer follow-up by a Breast Physician (or a Breast Cancer Nurse) in a dedicated local breast cancer clinic, rather than with their local General Practitioner. Drop-in clinics for the management of treatment related side effects and to provide advice to both develop and maintain good health are also highly valued by breast cancer survivors. PMID:24423927

Population Preferences for Health Care in Liberia: Insights for Rebuilding a Health System

PubMed Central

Kruk, Margaret E; Rockers, Peter C; Tornorlah Varpilah, S; Macauley, Rose

2011-01-01

Objective To quantify the influence of health system attributes, particularly quality of care, on preferences for health clinics in Liberia, a country with a high burden of disease that is rebuilding its health system after 14 years of civil war. Data Sources/Study Setting Informed by focus group discussions, a discrete choice experiment (DCE) was designed to assess preferences for structure and process of care at health clinics. The DCE was fielded in rural, northern Liberia as part of a 2008 population-based survey on health care utilization. Data Collection The survey response rate was 98 percent with DCE data available for 1,431 respondents. Mixed logit models were used to estimate the influence of six attributes on choice of hypothetical clinics for a future illness. Principal Findings Participants' choice of clinic was most influenced by provision of a thorough physical exam and consistent availability of medicines. Respectful treatment and government (versus NGO) management marginally increased utility, whereas waiting time was not significant. Conclusions Liberians value technical quality of care over convenience, courtesy, and public management in selecting clinics for curative care. This suggests that investments in improved competence of providers and availability of medicines may increase population utilization of essential services as well as promote better clinical outcomes. PMID:21517835

The Influences of Landscape Features on Visitation of Hospital Green Spaces—A Choice Experiment Approach

PubMed Central

Chang, Kaowen Grace; Chien, Hungju

2017-01-01

Studies have suggested that visiting and viewing landscaping at hospitals accelerates patient’s recovery from surgery and help staff’s recovery from mental fatigue. To plan and construct such landscapes, we need to unravel landscape features desirable to different groups so that the space can benefit a wide range of hospital users. Using discrete choice modeling, we developed experimental choice sets to investigate how landscape features influence the visitations of different users in a large regional hospital in Taiwan. The empirical survey provides quantitative estimates of the influence of each landscape feature on four user groups, including patients, caregivers, staff, and neighborhood residents. Our findings suggest that different types of features promote visits from specific user groups. Landscape features facilitating physical activities effectively encourage visits across user groups especially for caregivers and staff. Patients in this study specify a strong need for contact with nature. The nearby community favors the features designed for children’s play and family activities. People across user groups value the features that provide a mitigated microclimate of comfort, such as a shelter. Study implications and limitations are also discussed. Our study provides information essential for creating a better healing environment in a hospital setting. PMID:28678168

Population preferences for health care in liberia: insights for rebuilding a health system.

PubMed

Kruk, Margaret E; Rockers, Peter C; Tornorlah Varpilah, S; Macauley, Rose

2011-12-01

OBJECTIVE. To quantify the influence of health system attributes, particularly quality of care, on preferences for health clinics in Liberia, a country with a high burden of disease that is rebuilding its health system after 14 years of civil war. DATA SOURCES/STUDY SETTING. Informed by focus group discussions, a discrete choice experiment (DCE) was designed to assess preferences for structure and process of care at health clinics. The DCE was fielded in rural, northern Liberia as part of a 2008 population-based survey on health care utilization. DATA COLLECTION. The survey response rate was 98 percent with DCE data available for 1,431 respondents. Mixed logit models were used to estimate the influence of six attributes on choice of hypothetical clinics for a future illness. PRINCIPAL FINDINGS. Participants' choice of clinic was most influenced by provision of a thorough physical exam and consistent availability of medicines. Respectful treatment and government (versus NGO) management marginally increased utility, whereas waiting time was not significant. CONCLUSIONS. Liberians value technical quality of care over convenience, courtesy, and public management in selecting clinics for curative care. This suggests that investments in improved competence of providers and availability of medicines may increase population utilization of essential services as well as promote better clinical outcomes. © Health Research and Educational Trust.

Psoriasis patients' willingness to accept side-effect risks for improved treatment efficacy.

PubMed

Kauf, Teresa L; Yang, Jui-Chen; Kimball, Alexa B; Sundaram, Murali; Bao, Yanjun; Okun, Martin; Mulani, Parvez; Hauber, A Brett; Johnson, F Reed

2015-01-01

Previous studies suggest that efficacy is more important than side-effect risks to psoriasis patients. However, those studies did not consider potentially fatal risks of biologic treatments. To quantify the risks patients are willing to accept for improvements in psoriasis symptoms. Adults with a self-reported physician diagnosis of psoriasis were recruited through the National Psoriasis Foundation. Using a discrete-choice experiment, patients completed a series of nine choice questions, each including a pair of hypothetical treatments. Treatments were defined by severity of plaques, body surface area (BSA), and 10-year risks of tuberculosis, serious infection and lymphoma. For complete clearance of 25% BSA with mild plaques, respondents (n = 1608) were willing to accept a 20% (95% confidence interval: 9-26%) risk of serious infection, 10% (5-15%) risk of tuberculosis and 2% (1-3%) risk of lymphoma. For complete clearance of 25% BSA with severe plaques, respondents were willing to accept a 54% (48-62%) risk of serious infection, 36% (28-49%) risk of tuberculosis and 8% (7-9%) risk of lymphoma. Respondents were asked to evaluate hypothetical scenarios. Actual treatment choices may differ. Respondents were willing to accept risks above likely clinical exposures for improvements in psoriasis symptoms. Individual risk tolerances may vary.

Relative judgment theory and the mediation of facial recognition: Implications for theories of eyewitness identification.

PubMed

McAdoo, Ryan M; Gronlund, Scott D

2016-01-01

Many in the eyewitness identification community believe that sequential lineups are superior to simultaneous lineups because simultaneous lineups encourage inappropriate choosing due to promoting comparisons among choices (a relative judgment strategy), but sequential lineups reduce this propensity by inducing comparisons of lineup members directly to memory rather than to each other (an absolute judgment strategy). Different versions of the relative judgment theory have implicated both discrete-state and continuous mediation of eyewitness decisions. The theory has never been formally specified, but (Yonelinas, J Exp Psychol Learn Mem Cogn 20:1341-1354, 1994) dual-process models provide one possible specification, thereby allowing us to evaluate how eyewitness decisions are mediated. We utilized a ranking task (Kellen and Klauer, J Exp Psychol Learn Mem Cogn 40:1795-1804, 2014) and found evidence for continuous mediation when facial stimuli match from study to test (Experiment 1) and when they mismatch (Experiment 2). This evidence, which is contrary to a version of relative judgment theory that has gained a lot of traction in the legal community, compels reassessment of the role that guessing plays in eyewitness identification. Future research should continue to test formal explanations in order to advance theory, expedite the development of new procedures that can enhance the reliability of eyewitness evidence, and to facilitate the exploration of task factors and emergent strategies that might influence when recognition is continuously or discretely mediated.

Dimers in Piecewise Temperleyan Domains

NASA Astrophysics Data System (ADS)

Russkikh, Marianna

2018-03-01

We study the large-scale behavior of the height function in the dimer model on the square lattice. Richard Kenyon has shown that the fluctuations of the height function on Temperleyan discretizations of a planar domain converge in the scaling limit (as the mesh size tends to zero) to the Gaussian Free Field with Dirichlet boundary conditions. We extend Kenyon's result to a more general class of discretizations. Moreover, we introduce a new factorization of the coupling function of the double-dimer model into two discrete holomorphic functions, which are similar to discrete fermions defined in Smirnov (Proceedings of the international congress of mathematicians (ICM), Madrid, Spain, 2006; Ann Math (2) 172:1435-1467, 2010). For Temperleyan discretizations with appropriate boundary modifications, the results of Kenyon imply that the expectation of the double-dimer height function converges to a harmonic function in the scaling limit. We use the above factorization to extend this result to the class of all polygonal discretizations, that are not necessarily Temperleyan. Furthermore, we show that, quite surprisingly, the expectation of the double-dimer height function in the Temperleyan case is exactly discrete harmonic (for an appropriate choice of Laplacian) even before taking the scaling limit.

GEMPIC: geometric electromagnetic particle-in-cell methods

NASA Astrophysics Data System (ADS)

Kraus, Michael; Kormann, Katharina; Morrison, Philip J.; Sonnendrücker, Eric

2017-08-01

We present a novel framework for finite element particle-in-cell methods based on the discretization of the underlying Hamiltonian structure of the Vlasov-Maxwell system. We derive a semi-discrete Poisson bracket, which retains the defining properties of a bracket, anti-symmetry and the Jacobi identity, as well as conservation of its Casimir invariants, implying that the semi-discrete system is still a Hamiltonian system. In order to obtain a fully discrete Poisson integrator, the semi-discrete bracket is used in conjunction with Hamiltonian splitting methods for integration in time. Techniques from finite element exterior calculus ensure conservation of the divergence of the magnetic field and Gauss' law as well as stability of the field solver. The resulting methods are gauge invariant, feature exact charge conservation and show excellent long-time energy and momentum behaviour. Due to the generality of our framework, these conservation properties are guaranteed independently of a particular choice of the finite element basis, as long as the corresponding finite element spaces satisfy certain compatibility conditions.

Impacts of invasive plants on Sandhill Crane (Grus canadensis) roosting habitat

USGS Publications Warehouse

Kessler, Andrew C.; Merchant, James W.; Allen, Craig R.; Shultz, Steven D.

2011-01-01

Invasive plants continue to spread in riparian ecosystems, causing both ecological and economic damage. This research investigated the impacts of common reed, purple loosestrife, riparian shrubland, and riparian woodlands on the quality and quantity of sandhill crane roosting habitat in the central Platte River, Nebraska, using a discrete choice model. A more detailed investigation of the impacts of common reed on sandhill crane roosting habitat was performed by forecasting a spread or contraction of this invasive plant. The discrete choice model indicates that riparian woodlands had the largest negative impact on sandhill crane roosting habitat. The forecasting results predict that a contraction of common reed could increase sandhill crane habitat availability by 50%, whereas an expansion could reduce the availability by as much as 250%. This suggests that if the distribution of common reed continues to expand in the central Platte River the availability of sandhill crane roosting habitat would likely be greatly reduced.

Investigating preferences for support with life after stroke: a discrete choice experiment.

PubMed

Burton, Christopher R; Fargher, Emily; Plumpton, Catrin; Roberts, Gwerfyl W; Owen, Heledd; Roberts, Eryl

2014-02-08

There is little evidence of service user preferences to guide the commissioning and improvement of services that support life after stroke. We report the first investigation of patients' and family carers' preferences for community services after stroke using a discrete choice experiment (DCE). Two workshops with patients and family carers (n = 8) explored stroke experiences, identifying attributes important in shaping views about service design, and piloted data collection strategies. Attributes were group versus individual support; service provider; additional support for social and leisure activities; and the total time required to access services. Patients and family carers were recruited six months post stroke-onset (mean 331 days) from four stroke services, and invited to participate in the DCE. Patients' general health (EQ5D) and functional dependence (Barthel Index) were also assessed. Of 474 eligible patients, 144 (30%) expressed an interest in the study, and 80 (56%) of these completed the survey questionnaire. 34 of 74 (46%) family carers recruited through patients completed the DCE. All four attributes were significant in shaping patients preferences for stroke support service delivery (p < 0.05), confirming the interpretation of workshop findings. Patients prefer help and support for emotional needs, communication problems and physical difficulties to be provided on an individual basis; and to be offered additional social and leisure activities that they are able to attend on their own. Patients would appear to prefer that voluntary organisations do not provide these services, although this may be linked to lack of experience of these services. Family carers would prefer help and support in their caring role on a one-to-one basis. Whilst health related quality of life is associated with preference for format of service, results were relatively consistent across sub-groups, with the exception of time since stroke, where social and leisure activities had a greater impact on preferences of established service users. The data provide unique insights into how preferences for community services that support life after stroke are shaped. This information can be used to inform both service re-design, and barriers to implementation that will need to be accounted for in policy shifts towards a more mixed economy of service provision.

Investigating the preferences of older people for telehealth as a new model of health care service delivery: A discrete choice experiment.

PubMed

Kaambwa, Billingsley; Ratcliffe, Julie; Shulver, Wendy; Killington, Maggie; Taylor, Alan; Crotty, Maria; Carati, Colin; Tieman, Jennifer; Wade, Victoria; Kidd, Michael R

2017-02-01

Introduction Telehealth approaches to health care delivery can potentially improve quality of care and clinical outcomes, reduce mortality and hospital utilisation, and complement conventional treatments. However, substantial research into the potential for integrating telehealth within health care in Australia, particularly in the provision of services relevant to older people, including palliative care, aged care and rehabilitation, is lacking. Furthermore, to date, no discrete choice experiment (DCE) studies internationally have sought the views and preferences of older people about the basic features that should make up a telehealth approach to these services. Methods Using a DCE, we investigated the relative importance of six salient features of telehealth (what aspects of care are to be pursued during telehealth sessions, distance to the nearest hospital or clinic, clinicians' attitude to telehealth, patients' experience of using technology, what types of assessments should be conducted face-to-face versus via telehealth sessions and the costs associated with receiving telehealth). Data were obtained from an online panel of older people aged 65 years and above, drawn from the Australian general population. Results The mean age for 330 study participants was 69 years. In general, individuals expressed strong preferences for telehealth services that offered all aspects of care, were relatively inexpensive and targeted specifically at individuals living in remote regions without easy access to a hospital or clinic. Participants also preferred telehealth services to be offered to individuals with some prior experience of using technology, provided by clinicians who were positive about telehealth but wanted all or some pre-telehealth health assessments to take place in a hospital or clinic. Preferences only differed by gender. Additionally, respondents did not feel that telehealth led to loss of privacy and confidentiality. Discussion Our findings indicate a preference amongst respondents for face-to-face pre-telehealth health assessments and, thereafter, a comprehensive telehealth model (in terms of services offered) targeted at those with some technological know-how as a substitute for attendance at hospitals and clinics, especially where these health facilities were far away from older people's homes. The findings may be usefully incorporated into the design of future telehealth models of service delivery for older people.

Conjoint analysis: using a market-based research model for healthcare decision making.

PubMed

Mele, Nancy L

2008-01-01

Conjoint analysis is a market-based research model that has been used by businesses for more than 35 years to predict consumer preferences in product design and purchasing. Researchers in medicine, healthcare economics, and health policy have discovered the value of this methodology in determining treatment preferences, resource allocation, and willingness to pay. To describe the conjoint analysis methodology and explore value-added applications in nursing research. Conjoint analysis methodology is described, using examples from the healthcare and business literature, and personal experience with the method. Nurses are called upon to increase interdisciplinary research, provide an evidence base for nursing practice, create patient-centered treatments, and revise nursing education. Other disciplines have met challenges like these using conjoint analysis and discrete choice modeling.

Who joins the network? Physicians' resistance to take budgetary co-responsibility.

PubMed

Rischatsch, Maurus

2015-03-01

Managed Care (MC) is expected to provide health care at a lower cost than conventional provision. Therefore, Switzerland intends to promote MC by forcing health insurers to write MC contracts and introducing budgetary co-responsibility for ambulatory care physicians. A discrete choice experiment conducted in 2011 including 872 physicians reveals a strong preference heterogeneity with respect to network participation and alternative remuneration schemes. The number of physicians working in networks is unlikely to rise on a voluntary basis, while general practitioners are more likely to join networks than specialists with surgical activities. For physicians considering joining networks, cost savings are predicted to be higher than the estimated willingness-to-accept payments. Copyright © 2014 Elsevier B.V. All rights reserved.

Numerical Error Estimation with UQ

NASA Astrophysics Data System (ADS)

Ackmann, Jan; Korn, Peter; Marotzke, Jochem

2014-05-01

Ocean models are still in need of means to quantify model errors, which are inevitably made when running numerical experiments. The total model error can formally be decomposed into two parts, the formulation error and the discretization error. The formulation error arises from the continuous formulation of the model not fully describing the studied physical process. The discretization error arises from having to solve a discretized model instead of the continuously formulated model. Our work on error estimation is concerned with the discretization error. Given a solution of a discretized model, our general problem statement is to find a way to quantify the uncertainties due to discretization in physical quantities of interest (diagnostics), which are frequently used in Geophysical Fluid Dynamics. The approach we use to tackle this problem is called the "Goal Error Ensemble method". The basic idea of the Goal Error Ensemble method is that errors in diagnostics can be translated into a weighted sum of local model errors, which makes it conceptually based on the Dual Weighted Residual method from Computational Fluid Dynamics. In contrast to the Dual Weighted Residual method these local model errors are not considered deterministically but interpreted as local model uncertainty and described stochastically by a random process. The parameters for the random process are tuned with high-resolution near-initial model information. However, the original Goal Error Ensemble method, introduced in [1], was successfully evaluated only in the case of inviscid flows without lateral boundaries in a shallow-water framework and is hence only of limited use in a numerical ocean model. Our work consists in extending the method to bounded, viscous flows in a shallow-water framework. As our numerical model, we use the ICON-Shallow-Water model. In viscous flows our high-resolution information is dependent on the viscosity parameter, making our uncertainty measures viscosity-dependent. We will show that we can choose a sensible parameter by using the Reynolds-number as a criteria. Another topic, we will discuss is the choice of the underlying distribution of the random process. This is especially of importance in the scope of lateral boundaries. We will present resulting error estimates for different height- and velocity-based diagnostics applied to the Munk gyre experiment. References [1] F. RAUSER: Error Estimation in Geophysical Fluid Dynamics through Learning; PhD Thesis, IMPRS-ESM, Hamburg, 2010 [2] F. RAUSER, J. MAROTZKE, P. KORN: Ensemble-type numerical uncertainty quantification from single model integrations; SIAM/ASA Journal on Uncertainty Quantification, submitted

Estimating demand for perennial pigeon pea in Malawi using choice experiments.

PubMed

Waldman, Kurt B; Ortega, David L; Richardson, Robert B; Snapp, Sieglinde S

2017-01-01

Perennial crops have numerous ecological and agronomic advantages over their annual counterparts. We estimate discrete choice models to evaluate farmers' preferences for perennial attributes of pigeon pea intercropped with maize in central and southern Malawi. Pigeon pea is a nitrogen-fixing leguminous crop, which has the potential to ameliorate soil fertility problems related to continuous maize cultivation, which are common in Southern Africa. Adoption of annual pigeon pea is relatively low but perennial production of pigeon pea may be more appealing to farmers due to some of the ancillary benefits associated with perenniality. We model perennial production of pigeon pea as a function of the attributes that differ between annual and perennial production: lower labor and seed requirements resulting from a single planting with multiple harvests, enhanced soil fertility and higher levels of biomass production. The primary tradeoff associated with perennial pigeon pea intercropped with maize is competition with maize in subsequent years of production. While maize yield is approximately twice as valuable to farmers as pigeon pea yield, we find positive yet heterogeneous demand for perenniality driven by soil fertility improvements and pigeon pea grain yield.

Individual preferences for physical exercise as secondary prevention for non-specific low back pain: A discrete choice experiment

PubMed Central

Hagberg, Jan; Axén, Iben; Kwak, Lydia; Lohela-Karlsson, Malin; Skillgate, Eva; Dahlgren, Gunilla; Jensen, Irene

2017-01-01

Background Exercise is effective in improving non-specific low back pain (LBP). Certain components of physical exercise, such as the type, intensity and frequency of exercise, are likely to influence participation among working adults with non-specific LBP, but the value and relative importance of these components remain unknown. The study’s aim was to examine such specific components and their influence on individual preferences for exercise for secondary prevention of non-specific LBP among working adults. Methods In a discrete choice experiment, working individuals with non-specific LBP answered a web-based questionnaire. Each respondent was given ten pairs of hypothetical exercise programs and asked to choose one option from each pair. The choices comprised six attributes of exercise (i.e., type of training, design, intensity, frequency, proximity and incentives), each with either three or four levels. A conditional logit regression that reflected the random utility model was used to analyze the responses. Results The final study population consisted of 112 participants. The participants’ preferred exercise option was aerobic (i.e., cardiovascular) rather than strength training, group exercise with trainer supervision, rather than individual or unsupervised exercise. They also preferred high intensity exercise performed at least once or twice per week. The most popular types of incentive were exercise during working hours and a wellness allowance rather than coupons for sports goods. The results show that the relative value of some attribute levels differed between young adults (age ≤ 44 years) and older adults (age ≥ 45 years) in terms of the level of trainer supervision required, exercise intensity, travel time to exercise location and financial incentives. For active study participants, exercise frequency (i.e., twice per week, 1.15; CI: 0.25; 2.06) influenced choice of exercise. For individuals with more than one child, travel time (i.e., 20 minutes, -0.55; CI: 0.65; 3.26) was also an influential attribute for choice of exercise, showing that people with children at home preferred to exercise close to home. Conclusions This study adds to our knowledge about what types of exercise working adults with back pain are most likely to participate in. The exercise should be a cardiovascular type of training carried out in a group with trainer supervision. It should also be of high intensity and preferably performed twice per week during working hours. Coupons for sports goods do not appear to motivate physical activity among workers with LBP. The findings of the study could have a substantial impact on the planning and development of exercise provision and promotion strategies to improve non-specific LBP. Providers and employers may be able to improve participation in exercise programs for adults with non-specific LBP by focusing on the exercise components which are the most attractive. This in turn would improve satisfaction and adherence to exercise interventions aimed at preventing recurrent non-specific LBP. PMID:29244841

Individual preferences for physical exercise as secondary prevention for non-specific low back pain: A discrete choice experiment.

PubMed

Aboagye, Emmanuel; Hagberg, Jan; Axén, Iben; Kwak, Lydia; Lohela-Karlsson, Malin; Skillgate, Eva; Dahlgren, Gunilla; Jensen, Irene

2017-01-01

Exercise is effective in improving non-specific low back pain (LBP). Certain components of physical exercise, such as the type, intensity and frequency of exercise, are likely to influence participation among working adults with non-specific LBP, but the value and relative importance of these components remain unknown. The study's aim was to examine such specific components and their influence on individual preferences for exercise for secondary prevention of non-specific LBP among working adults. In a discrete choice experiment, working individuals with non-specific LBP answered a web-based questionnaire. Each respondent was given ten pairs of hypothetical exercise programs and asked to choose one option from each pair. The choices comprised six attributes of exercise (i.e., type of training, design, intensity, frequency, proximity and incentives), each with either three or four levels. A conditional logit regression that reflected the random utility model was used to analyze the responses. The final study population consisted of 112 participants. The participants' preferred exercise option was aerobic (i.e., cardiovascular) rather than strength training, group exercise with trainer supervision, rather than individual or unsupervised exercise. They also preferred high intensity exercise performed at least once or twice per week. The most popular types of incentive were exercise during working hours and a wellness allowance rather than coupons for sports goods. The results show that the relative value of some attribute levels differed between young adults (age ≤ 44 years) and older adults (age ≥ 45 years) in terms of the level of trainer supervision required, exercise intensity, travel time to exercise location and financial incentives. For active study participants, exercise frequency (i.e., twice per week, 1.15; CI: 0.25; 2.06) influenced choice of exercise. For individuals with more than one child, travel time (i.e., 20 minutes, -0.55; CI: 0.65; 3.26) was also an influential attribute for choice of exercise, showing that people with children at home preferred to exercise close to home. This study adds to our knowledge about what types of exercise working adults with back pain are most likely to participate in. The exercise should be a cardiovascular type of training carried out in a group with trainer supervision. It should also be of high intensity and preferably performed twice per week during working hours. Coupons for sports goods do not appear to motivate physical activity among workers with LBP. The findings of the study could have a substantial impact on the planning and development of exercise provision and promotion strategies to improve non-specific LBP. Providers and employers may be able to improve participation in exercise programs for adults with non-specific LBP by focusing on the exercise components which are the most attractive. This in turn would improve satisfaction and adherence to exercise interventions aimed at preventing recurrent non-specific LBP.

Valuing Non-market Benefits of Rehabilitation of Hydrologic Cycle Improvements in the Anyangcheon Watershed: Using Mixed Logit Models

NASA Astrophysics Data System (ADS)

Yoo, J.; Kong, K.

2010-12-01

This research the findings from a discrete-choice experiment designed to estimate the economic benefits associated with the Anyangcheon watershed improvements in Rep. of Korea. The Anyangcheon watershed has suffered from streamflow depletion and poor stream quality, which often negatively affect instream and near-stream ecologic integrity, as well as water supply. Such distortions in the hydrologic cycle mainly result from rapid increase of impermeable area due to urbanization, decreases of baseflow runoff due to groundwater pumping, and reduced precipitation inputs driven by climate forcing. As well, combined sewer overflows and increase of non-point source pollution from urban regions decrease water quality. The appeal of choice experiments (CE) in economic analysis is that it is based on random utility theory (McFadden, 1974; Ben-Akiva and Lerman, 1985). In contrast to contingent valuation method (CVM), which asks people to choose between a base case and a specific alternative, CE asks people to choice between cases that are described by attributes. The attributes of this study were selected from hydrologic vulnerability components that represent flood damage possibility, instreamflow depletion, water quality deterioration, form of the watershed and tax. Their levels were divided into three grades include status quo. Two grades represented the ideal conditions. These scenarios were constructed from a 35 orthogonal main effect design. This design resulted in twenty-seven choice sets. The design had nine different choice scenarios presented to each respondent. The most popular choice models in use are the conditional logit (CNL). This model provides closed-form choice probability calculation. The shortcoming of CNL comes from irrelevant alternatives (IIA). In this paper, the mixed logit (ML) is applied to allow the coefficient’s variation for random taste heterogeneity in the population. The mixed logit model(with normal distributions for the attributes) fit the data best, indication that allowing for both heterogeneous preferences across households and correlation between repeated choices may represent actual choice behaviors best of all the estimated models. The annual benefits to improve of the Anyancheon watershed for 1% improvement of each attribute was 406.7 billion Won(0.34 billion USD). This study is expected to contribute to the decision-making process for policy-makers by providing useful methodological framework and quantitative information related to watershed improvement projects.Table 1. Estimated Results of Conditional Logit and Mixed Logit Model 1) t-values are shown in brackets

Proportional exponentiated link transformed hazards (ELTH) models for discrete time survival data with application

PubMed Central

Joeng, Hee-Koung; Chen, Ming-Hui; Kang, Sangwook

2015-01-01

Discrete survival data are routinely encountered in many fields of study including behavior science, economics, epidemiology, medicine, and social science. In this paper, we develop a class of proportional exponentiated link transformed hazards (ELTH) models. We carry out a detailed examination of the role of links in fitting discrete survival data and estimating regression coefficients. Several interesting results are established regarding the choice of links and baseline hazards. We also characterize the conditions for improper survival functions and the conditions for existence of the maximum likelihood estimates under the proposed ELTH models. An extensive simulation study is conducted to examine the empirical performance of the parameter estimates under the Cox proportional hazards model by treating discrete survival times as continuous survival times, and the model comparison criteria, AIC and BIC, in determining links and baseline hazards. A SEER breast cancer dataset is analyzed in details to further demonstrate the proposed methodology. PMID:25772374

On the consistency between nearest-neighbor peridynamic discretizations and discretized classical elasticity models

DOE PAGES

Seleson, Pablo; Du, Qiang; Parks, Michael L.

2016-08-16

The peridynamic theory of solid mechanics is a nonlocal reformulation of the classical continuum mechanics theory. At the continuum level, it has been demonstrated that classical (local) elasticity is a special case of peridynamics. Such a connection between these theories has not been extensively explored at the discrete level. This paper investigates the consistency between nearest-neighbor discretizations of linear elastic peridynamic models and finite difference discretizations of the Navier–Cauchy equation of classical elasticity. While nearest-neighbor discretizations in peridynamics have been numerically observed to present grid-dependent crack paths or spurious microcracks, this paper focuses on a different, analytical aspect of suchmore » discretizations. We demonstrate that, even in the absence of cracks, such discretizations may be problematic unless a proper selection of weights is used. Specifically, we demonstrate that using the standard meshfree approach in peridynamics, nearest-neighbor discretizations do not reduce, in general, to discretizations of corresponding classical models. We study nodal-based quadratures for the discretization of peridynamic models, and we derive quadrature weights that result in consistency between nearest-neighbor discretizations of peridynamic models and discretized classical models. The quadrature weights that lead to such consistency are, however, model-/discretization-dependent. We motivate the choice of those quadrature weights through a quadratic approximation of displacement fields. The stability of nearest-neighbor peridynamic schemes is demonstrated through a Fourier mode analysis. Finally, an approach based on a normalization of peridynamic constitutive constants at the discrete level is explored. This approach results in the desired consistency for one-dimensional models, but does not work in higher dimensions. The results of the work presented in this paper suggest that even though nearest-neighbor discretizations should be avoided in peridynamic simulations involving cracks, such discretizations are viable, for example for verification or validation purposes, in problems characterized by smooth deformations. Furthermore, we demonstrate that better quadrature rules in peridynamics can be obtained based on the functional form of solutions.« less

Α4β2 and α7 nicotinic acetylcholine receptor binding predicts choice preference in two cost benefit decision-making tasks.

PubMed

Mendez, I A; Damborsky, J C; Winzer-Serhan, U H; Bizon, J L; Setlow, B

2013-01-29

Nicotinic receptors have been linked to a wide range of cognitive and behavioral functions, but surprisingly little is known about their involvement in cost benefit decision making. The goal of these experiments was to determine how nicotinic acetylcholine receptor (nAChR) expression is related to two forms of cost benefit decision making. Male Long Evans rats were tested in probability- and delay-discounting tasks, which required discrete trial choices between a small reward and a large reward associated with varying probabilities of omission and varying delays to reward delivery, respectively. Following testing, radioligand binding to α4β2 and α7 nAChR subtypes in brain regions implicated in cost benefit decision making was examined. Significant linear relationships were observed between choice of the large delayed reward in the delay discounting task and α4β2 receptor binding in both the dorsal and ventral hippocampus. Additionally, trends were found suggesting that choice of the large costly reward in both discounting tasks was inversely related to α4β2 receptor binding in the medial prefrontal cortex and nucleus accumbens shell. Similar trends suggested that choice of the large delayed reward in the delay discounting task was inversely related to α4β2 receptor binding in the orbitofrontal cortex, nucleus accumbens core, and basolateral amygdala, as well as to α7 receptor binding in the basolateral amygdala. These data suggest that nAChRs (particularly α4β2) play both unique and common roles in decisions that require consideration of different types of reward costs. Copyright © 2012 IBRO. Published by Elsevier Ltd. All rights reserved.

Effects of financial incentives on motivating physical activity among older adults: results from a discrete choice experiment.

PubMed

Farooqui, Muhammad Assad; Tan, Yock-Theng; Bilger, Marcel; Finkelstein, Eric A

2014-02-10

There is extensive evidence that regular physical activity confers numerous health benefits. Despite this, high rates of physical inactivity prevail among older adults. This study aimed to ascertain if incentives could be effective in motivating physical activity through improving uptake of walking programs, either with or without an enrolment fee to cover corresponding costs. A discrete-choice conjoint survey was fielded to a national sample of older adults in Singapore. Each respondent was given ten pairs of hypothetical walking programs and asked to choose the option they preferred. Each option varied along several dimensions, including the level and type (cash, voucher, or health savings credit) of incentive and an enrolment fee. For each option, they were asked how likely they would be to join their preferred program. A random utility model (RUM) was used to analyze the responses. Results suggest that a free 6-month program with a $500 cash incentive would generate enrolment rates of 58.5%; charging $50 to enroll lowers this to 55.7%. In terms of incentive type, cash payments were the most preferred incentive but not significantly different from supermarket vouchers. Both were preferred to health savings credits and sporting goods vouchers. Concerns of adverse selection were minimal because those who were inactive represented at least 72% of new participants for any offered program(s) and were the majority. Study results demonstrate the potential for even modest incentives to increase program uptake among inactive older adults. Moreover, although cash was the most preferred option, supermarket vouchers, which could potentially be purchased at a discount, were a close alternative. Results also suggest that an enrolment fee is a viable option to offset the costs of incentives as it has only minimal impact on participation.

A scalable block-preconditioning strategy for divergence-conforming B-spline discretizations of the Stokes problem

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cortes, Adriano M.; Dalcin, Lisandro; Sarmiento, Adel F.

The recently introduced divergence-conforming B-spline discretizations allow the construction of smooth discrete velocity–pressure pairs for viscous incompressible flows that are at the same time inf–sup stable and pointwise divergence-free. When applied to the discretized Stokes problem, these spaces generate a symmetric and indefinite saddle-point linear system. The iterative method of choice to solve such system is the Generalized Minimum Residual Method. This method lacks robustness, and one remedy is to use preconditioners. For linear systems of saddle-point type, a large family of preconditioners can be obtained by using a block factorization of the system. In this paper, we show howmore » the nesting of “black-box” solvers and preconditioners can be put together in a block triangular strategy to build a scalable block preconditioner for the Stokes system discretized by divergence-conforming B-splines. Lastly, besides the known cavity flow problem, we used for benchmark flows defined on complex geometries: an eccentric annulus and hollow torus of an eccentric annular cross-section.« less

A scalable block-preconditioning strategy for divergence-conforming B-spline discretizations of the Stokes problem

DOE PAGES

Cortes, Adriano M.; Dalcin, Lisandro; Sarmiento, Adel F.; ...

2016-10-19

The recently introduced divergence-conforming B-spline discretizations allow the construction of smooth discrete velocity–pressure pairs for viscous incompressible flows that are at the same time inf–sup stable and pointwise divergence-free. When applied to the discretized Stokes problem, these spaces generate a symmetric and indefinite saddle-point linear system. The iterative method of choice to solve such system is the Generalized Minimum Residual Method. This method lacks robustness, and one remedy is to use preconditioners. For linear systems of saddle-point type, a large family of preconditioners can be obtained by using a block factorization of the system. In this paper, we show howmore » the nesting of “black-box” solvers and preconditioners can be put together in a block triangular strategy to build a scalable block preconditioner for the Stokes system discretized by divergence-conforming B-splines. Lastly, besides the known cavity flow problem, we used for benchmark flows defined on complex geometries: an eccentric annulus and hollow torus of an eccentric annular cross-section.« less

High temporal resolution delayed analysis of clinical microdialysate streams† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c7an01209h

PubMed Central

Gowers, S. A. N.; Hamaoui, K.; Cunnea, P.; Anastasova, S.; Curto, V. F.; Vadgama, P.; Yang, G.-Z.; Papalois, V.; Drakakis, E. M.; Fotopoulou, C.; Weber, S. G.

2018-01-01

This paper presents the use of tubing to store clinical microdialysis samples for delayed analysis with high temporal resolution, offering an alternative to traditional discrete offline microdialysis sampling. Samples stored in this way were found to be stable for up to 72 days at –80 °C. Examples of how this methodology can be applied to glucose and lactate measurement in a wide range of in vivo monitoring experiments are presented. This paper presents a general model, which allows for an informed choice of tubing parameters for a given storage time and flow rate avoiding high back pressure, which would otherwise cause the microdialysis probe to leak, while maximising temporal resolution. PMID:29336454

Shared decision making in mental health: the importance for current clinical practice.

PubMed

Alguera-Lara, Victoria; Dowsey, Michelle M; Ride, Jemimah; Kinder, Skye; Castle, David

2017-12-01

We reviewed the literature on shared decision making (regarding treatments in psychiatry), with a view to informing our understanding of the decision making process and the barriers that exist in clinical practice. Narrative review of published English-language articles. After culling, 18 relevant articles were included. Themes identified included models of psychiatric care, benefits for patients, and barriers. There is a paucity of published studies specifically related to antipsychotic medications. Shared decision making is a central part of the recovery paradigm and is of increasing importance in mental health service delivery. The field needs to better understand the basis on which decisions are reached regarding psychiatric treatments. Discrete choice experiments might be useful to inform the development of tools to assist shared decision making in psychiatry.

Discrete emotions predict changes in cognition, judgment, experience, behavior, and physiology: a meta-analysis of experimental emotion elicitations.

PubMed

Lench, Heather C; Flores, Sarah A; Bench, Shane W

2011-09-01

Our purpose in the present meta-analysis was to examine the extent to which discrete emotions elicit changes in cognition, judgment, experience, behavior, and physiology; whether these changes are correlated as would be expected if emotions organize responses across these systems; and which factors moderate the magnitude of these effects. Studies (687; 4,946 effects, 49,473 participants) were included that elicited the discrete emotions of happiness, sadness, anger, and anxiety as independent variables with adults. Consistent with discrete emotion theory, there were (a) moderate differences among discrete emotions; (b) differences among discrete negative emotions; and (c) correlated changes in behavior, experience, and physiology (cognition and judgment were mostly not correlated with other changes). Valence, valence-arousal, and approach-avoidance models of emotion were not as clearly supported. There was evidence that these factors are likely important components of emotion but that they could not fully account for the pattern of results. Most emotion elicitations were effective, although the efficacy varied with the emotions being compared. Picture presentations were overall the most effective elicitor of discrete emotions. Stronger effects of emotion elicitations were associated with happiness versus negative emotions, self-reported experience, a greater proportion of women (for elicitations of happiness and sadness), omission of a cover story, and participants alone versus in groups. Conclusions are limited by the inclusion of only some discrete emotions, exclusion of studies that did not elicit discrete emotions, few available effect sizes for some contrasts and moderators, and the methodological rigor of included studies. (PsycINFO Database Record (c) 2011 APA, all rights reserved).

Effects of acute administration of nicotinic and muscarinic cholinergic agonists and antagonists on performance in different cost–benefit decision making tasks in rats

PubMed Central

Mendez, Ian A.; Gilbert, Ryan J.; Bizon, Jennifer L.

2012-01-01

Rationale Alterations in cost–benefit decision making accompany numerous neuropsychiatric conditions, including schizophrenia, attention deficit hyperactivity disorder, and addiction. Central cholinergic systems have been linked to the etiology and/or treatment of many of these conditions, but little is known about the role of cholinergic signaling in cost–benefit decision making. Objectives The goal of these experiments was to determine how cholinergic signaling is involved in cost–benefit decision making, using a behavioral pharmacological approach. Methods Male Long-Evans rats were trained in either “probability discounting” or “delay discounting” tasks, in which rats made discrete-trial choices between a small food reward and a large food reward associated with either varying probabilities of omission or varying delays to delivery, respectively. The effects of acute administration of different doses of nicotinic and muscarinic acetylcholine receptor agonists and antagonists were assessed in each task. Results In the probability discounting task, acute nicotine administration (1.0 mg/kg) significantly increased choice of the large risky reward, and control experiments suggested that this was due to robust nicotine-induced impairments in behavioral flexibility. In the delay discounting task, the muscarinic antagonists scopolamine (0.03, 0.1, and 0.3 mg/kg) and atropine (0.3 mg/kg) both significantly increased choice of the small immediate reward. Neither mecamylamine nor oxotremorine produced reliable effects on either of the decision making tasks. Conclusions These data suggest that cholinergic receptors play multiple roles in decision making contexts which include consideration of reward delay or probability. These roles should be considered when targeting these receptors for therapeutic purposes. PMID:22760484

Dynamic combination of sensory and reward information under time pressure

PubMed Central

Farashahi, Shiva; Kao, Chang-Hao

2018-01-01

When making choices, collecting more information is beneficial but comes at the cost of sacrificing time that could be allocated to making other potentially rewarding decisions. To investigate how the brain balances these costs and benefits, we conducted a series of novel experiments in humans and simulated various computational models. Under six levels of time pressure, subjects made decisions either by integrating sensory information over time or by dynamically combining sensory and reward information over time. We found that during sensory integration, time pressure reduced performance as the deadline approached, and choice was more strongly influenced by the most recent sensory evidence. By fitting performance and reaction time with various models we found that our experimental results are more compatible with leaky integration of sensory information with an urgency signal or a decision process based on stochastic transitions between discrete states modulated by an urgency signal. When combining sensory and reward information, subjects spent less time on integration than optimally prescribed when reward decreased slowly over time, and the most recent evidence did not have the maximal influence on choice. The suboptimal pattern of reaction time was partially mitigated in an equivalent control experiment in which sensory integration over time was not required, indicating that the suboptimal response time was influenced by the perception of imperfect sensory integration. Meanwhile, during combination of sensory and reward information, performance did not drop as the deadline approached, and response time was not different between correct and incorrect trials. These results indicate a decision process different from what is involved in the integration of sensory information over time. Together, our results not only reveal limitations in sensory integration over time but also illustrate how these limitations influence dynamic combination of sensory and reward information. PMID:29584717

Preferences for prenatal testing among pregnant women, partners and health professionals.

PubMed

Lund, Ida Charlotte Bay; Becher, Naja; Petersen, Olav Bjørn; Hill, Melissa; Chitty, Lyn; Vogel, Ida

2018-05-01

Cell-free DNA testing (cfDNA testing) in maternal plasma has recently been implemented in Danish healthcare. Prior to that we wanted to evaluate the preferences among pregnant women, partners and health professionals regarding cfDNA testing compared with invasive prenatal diagnostics. Responders were recruited at public hospitals in the Central and North Denmark Regions. Stated preferences for prenatal testing were obtained through an online questionnaire incorporating a discrete choice experiment. Test choices differed according to attributes such as risk of miscarriage (none or small) and genetic information provided by the test; simple (Down syndrome only) or comprehensive (chromosomal abnormalities beyond Down syndrome). No risk of miscarriage was the key attribute affecting the preferences of women (n = 315) and partners (n = 102). However, women with experiences of invasive testing placed more emphasis on comprehensive genetic information and less on risk of miscarriage compared with other women. Likewise, foetal medicine experts, obstetricians and sonographers (n = 57) had a greater preference for comprehensive genetic information than midwives who were not directly involved in counselling for prenatal testing (n = 48). As safety seems to affect the majority of pregnant couples' choice behaviour, thorough pre-test counselling by trained health professionals is of paramount importance. Aarhus University and The Foundation of 17-12-1981. This study was registered with the Danish Data Protection Agency (1-16-02-586-13/ 2007-58-0010). Articles published in the DMJ are “open access”. This means that the articles are distributed under the terms of the Creative Commons Attribution Non-commercial License, which permits any non-commercial use, distribution, and reproduction in any medium, provided the original author(s) and source are credited.

Effects of acute administration of nicotinic and muscarinic cholinergic agonists and antagonists on performance in different cost-benefit decision making tasks in rats.

PubMed

Mendez, Ian A; Gilbert, Ryan J; Bizon, Jennifer L; Setlow, Barry

2012-12-01

Alterations in cost-benefit decision making accompany numerous neuropsychiatric conditions, including schizophrenia, attention deficit hyperactivity disorder, and addiction. Central cholinergic systems have been linked to the etiology and/or treatment of many of these conditions, but little is known about the role of cholinergic signaling in cost-benefit decision making. The goal of these experiments was to determine how cholinergic signaling is involved in cost-benefit decision making, using a behavioral pharmacological approach. Male Long-Evans rats were trained in either "probability discounting" or "delay discounting" tasks, in which rats made discrete-trial choices between a small food reward and a large food reward associated with either varying probabilities of omission or varying delays to delivery, respectively. The effects of acute administration of different doses of nicotinic and muscarinic acetylcholine receptor agonists and antagonists were assessed in each task. In the probability discounting task, acute nicotine administration (1.0 mg/kg) significantly increased choice of the large risky reward, and control experiments suggested that this was due to robust nicotine-induced impairments in behavioral flexibility. In the delay discounting task, the muscarinic antagonists scopolamine (0.03, 0.1, and 0.3 mg/kg) and atropine (0.3 mg/kg) both significantly increased choice of the small immediate reward. Neither mecamylamine nor oxotremorine produced reliable effects on either of the decision making tasks. These data suggest that cholinergic receptors play multiple roles in decision making contexts which include consideration of reward delay or probability. These roles should be considered when targeting these receptors for therapeutic purposes.

Exclusive queueing model including the choice of service windows

NASA Astrophysics Data System (ADS)

Tanaka, Masahiro; Yanagisawa, Daichi; Nishinari, Katsuhiro

2018-01-01

In a queueing system involving multiple service windows, choice behavior is a significant concern. This paper incorporates the choice of service windows into a queueing model with a floor represented by discrete cells. We contrived a logit-based choice algorithm for agents considering the numbers of agents and the distances to all service windows. Simulations were conducted with various parameters of agent choice preference for these two elements and for different floor configurations, including the floor length and the number of service windows. We investigated the model from the viewpoint of transit times and entrance block rates. The influences of the parameters on these factors were surveyed in detail and we determined that there are optimum floor lengths that minimize the transit times. In addition, we observed that the transit times were determined almost entirely by the entrance block rates. The results of the presented model are relevant to understanding queueing systems including the choice of service windows and can be employed to optimize facility design and floor management.

A PREFERENCE-OPPORTUNITY-CHOICE FRAMEWORK WITH APPLICATIONS TO INTERGROUP FRIENDSHIP*

PubMed Central

Zeng, Zhen; Xie, Yu

2009-01-01

A longstanding objective of friendship research is to identify the effects of personal preference and structural opportunity on intergroup friendship choice. Although past studies have used various methods to separate preference from opportunity, researchers have not yet systematically compared the properties and implications of these methods. We put forward a general framework for discrete choice, where choice probability is specified as proportional to the product of preference and opportunity. To implement this framework, we propose a modification to the conditional logit model for estimating preference parameters free from the influence of opportunity structure. We then compare our approach to several alternative methods for separating preference and opportunity used in the friendship choice literature. As an empirical example, we test hypotheses of homophily and status asymmetry in friendship choice using data from the National Longitudinal Study of Adolescent Health. The example also demonstrates the approach of conducting a sensitivity analysis to examine how parameter estimates vary by specification of the opportunity structure. PMID:19569394

Incentives for non-physician health professionals to work in the rural and remote areas of Mozambique--a discrete choice experiment for eliciting job preferences.

PubMed

Honda, Ayako; Vio, Ferruccio

2015-04-26

Successfully motivating and retaining health workers is critical for the effective performance of health systems. In Mozambique, a shortage of health care professionals and low levels of staff motivation in rural and remote areas pose challenges to the provision of equitable health care delivery. This study provides quantitative information on the job preferences of non-physician health professionals in Mozambique, examining how different aspects of jobs are valued and how health professionals might respond to policy options that would post them to district hospitals in rural areas. The study used a discrete choice experiment (DCE) to elicit the job preferences of non-physician health professionals. Data collection took place in four Mozambique provinces: Maputo City, Maputo Province, Sofala and Nampula. DCE questionnaires were administered to 334 non-physician health professionals with specialized or university training ('mid-level specialists' and N1 and N2 categories). In addition, questionnaires were administered to 123 N1 and N2 students to enable comparison of the results for those with work experience with those without and determine how new N1 and N2 graduates can be attracted to rural posts. The results indicate that the provision of basic government housing has the greatest impact on the probability of choosing a job at a public health facility, followed by the provision of formal education opportunities and the availability of equipment and medicine at a health facility. The sub-group analysis suggests that job preferences vary according to stage of life and that incentive packages should vary accordingly. Recruitment strategies to encourage non-clinical professionals to work in rural/remote areas should also consider birthplace, as those born in rural/remote areas are more willing to work remotely. The study was undertaken within an overarching project that aimed to develop incentive packages for non-physician health professionals assigned to work in remote/rural areas. Based on the DCE results, the project team, together with the Mozambique Ministry of Health, has developed a range of health workforce retention strategies focusing on the provision of housing benefits and professional development opportunities to be utilized when assigning non-physician health professionals to rural/remote areas.

Patient Preferences for Injectable Treatments for Multiple Sclerosis in the United States: A Discrete-Choice Experiment.

PubMed

Poulos, Christine; Kinter, Elizabeth; Yang, Jui-Chen; Bridges, John F P; Posner, Joshua; Reder, Anthony T

2016-04-01

Patients' perceptions and experiences of medication efficacy, medication adverse events, dosing frequency, and dosing complexity have been found to influence adherence to injectable disease-modifying treatments (DMTs) in patients with multiple sclerosis (MS). The aim of this study was to quantify patient preferences for features of injectable DMTs for MS. Adult patients in the United States (US) with a self-reported diagnosis of MS completed an online discrete-choice experiment survey to assess preference for a number of features of a hypothetical injectable DMT. Patients chose hypothetical treatments in paired comparisons, where each treatment was described by features or attributes, including the number of years until disability progression, the number of relapses in the next 4 years, injection time, the frequency of injections, the occurrence of flu-like symptoms (FLS), and severity of injection-site reactions. Random-parameters logit regression parameters were used to calculate preference weights of attribute levels and the relative importance of changes in treatment features. Of the 205 patients who completed the survey, 192 provided sufficient data for analysis. The results indicated a broad range of tradeoffs that patients would be willing to make. With regard to this, the relative importance of an improvement in the number of years until disability progression from 1 to 2 (i.e., vertical distance between preference weights for these attribute levels) was 0.9 [95% confidence interval (CI) 0.5-1.2], the relative importance of this change was approximately equivalent to that of an improvement from 12 injections per month to two (mean 0.8, 95% CI 0.4-1.2), or approximately equivalent to a decrease from four to one relapses in the next 4 years (mean 0.8, 95% CI 0.5-1.2), or FLS 3 days after every injection to 3 days after some injections (mean 1.0, 95% CI 0.6-1.4). These results suggest that an improvement in treatment efficacy may be as important as a reduction in injection frequency or a reduction in some adverse events for patients who self-administer injectable DMTs for MS. Understanding the preferences of patients who use injectable treatments will inform the development of such treatments, which may in turn improve patient medication adherence and well-being.

Fiber-dependent deautonomization of integrable 2D mappings and discrete Painlevé equations

NASA Astrophysics Data System (ADS)

Carstea, Adrian Stefan; Dzhamay, Anton; Takenawa, Tomoyuki

2017-10-01

It is well known that two-dimensional mappings preserving a rational elliptic fibration, like the Quispel-Roberts-Thompson mappings, can be deautonomized to discrete Painlevé equations. However, the dependence of this procedure on the choice of a particular elliptic fiber has not been sufficiently investigated. In this paper we establish a way of performing the deautonomization for a pair of an autonomous mapping and a fiber. Starting from a single autonomous mapping but varying the type of a chosen fiber, we obtain different types of discrete Painlevé equations using this deautonomization procedure. We also introduce a technique for reconstructing a mapping from the knowledge of its induced action on the Picard group and some additional geometric data. This technique allows us to obtain factorized expressions of discrete Painlevé equations, including the elliptic case. Further, by imposing certain restrictions on such non-autonomous mappings we obtain new and simple elliptic difference Painlevé equations, including examples whose symmetry groups do not appear explicitly in Sakai’s classification.

Brain without mind: Computer simulation of neural networks with modifiable neuronal interactions

NASA Astrophysics Data System (ADS)

Clark, John W.; Rafelski, Johann; Winston, Jeffrey V.

1985-07-01

Aspects of brain function are examined in terms of a nonlinear dynamical system of highly interconnected neuron-like binary decision elements. The model neurons operate synchronously in discrete time, according to deterministic or probabilistic equations of motion. Plasticity of the nervous system, which underlies such cognitive collective phenomena as adaptive development, learning, and memory, is represented by temporal modification of interneuronal connection strengths depending on momentary or recent neural activity. A formal basis is presented for the construction of local plasticity algorithms, or connection-modification routines, spanning a large class. To build an intuitive understanding of the behavior of discrete-time network models, extensive computer simulations have been carried out (a) for nets with fixed, quasirandom connectivity and (b) for nets with connections that evolve under one or another choice of plasticity algorithm. From the former experiments, insights are gained concerning the spontaneous emergence of order in the form of cyclic modes of neuronal activity. In the course of the latter experiments, a simple plasticity routine (“brainwashing,” or “anti-learning”) was identified which, applied to nets with initially quasirandom connectivity, creates model networks which provide more felicitous starting points for computer experiments on the engramming of content-addressable memories and on learning more generally. The potential relevance of this algorithm to developmental neurobiology and to sleep states is discussed. The model considered is at the same time a synthesis of earlier synchronous neural-network models and an elaboration upon them; accordingly, the present article offers both a focused review of the dynamical properties of such systems and a selection of new findings derived from computer simulation.

Emotion regulation choice: the role of environmental affordances.

PubMed

Suri, Gaurav; Sheppes, Gal; Young, Gerald; Abraham, Damon; McRae, Kateri; Gross, James J

2017-09-01

Which emotion regulation strategy one uses in a given context can have profound affective, cognitive, and social consequences. It is therefore important to understand the determinants of emotion regulation choice. Many prior studies have examined person-specific, internal determinants of emotion regulation choice. Recently, it has become clear that external variables that are properties of the stimulus can also influence emotion regulation choice. In the present research, we consider whether reappraisal affordances, defined as the opportunities for re-interpretation of a stimulus that are inherent in that stimulus, can shape individuals' emotion regulation choices. We show that reappraisal affordances have stability across people and across time (Study 1), and are confounded with emotional intensity for a standardised set of picture stimuli (Study 2). Since emotional intensity has been shown to drive emotion regulation choice, we construct a context in which emotional intensity is separable from reappraisal affordances (Study 3) and use this context to show that reappraisal affordances powerfully influence emotion regulation choice even when emotional intensity and discrete emotions are taken into account (Study 4).

Quantifying benefit-risk preferences for new medicines in rare disease patients and caregivers.

PubMed

Morel, T; Aymé, S; Cassiman, D; Simoens, S; Morgan, M; Vandebroek, M

2016-05-26

Rare disease patients and caregivers face uncommon, serious, debilitating conditions often characterised by poor prognosis and limited treatment options. This study aimed to explore what they consider of value when choosing between hypothetical therapeutic options and to quantify both their benefit-risk preferences and the influence of disease context. A mixed-methods survey with patients and caregivers was conducted in the United Kingdom across a range of rare diseases. Discrete-choice experiments that compared hypothetical treatment profiles of benefits and risks were used to measure respondent preferences across a set of seven attributes related to health outcomes, safety, and process of care. Bespoke questions on current disease management and the joint use of the 12-item WHODAS 2.0 questionnaire and of two Likert scales capturing self- and proxy-assessed disease-induced threat to life and impairment were implemented to describe disease context. Additionally, qualitative insights on the definitions of value and risk were collected from respondents. Final study sample included 721 patients and 152 informal caregivers, across 52 rare diseases. When choosing between hypothetical novel treatments for rare diseases, respondents attributed most importance to drug response, risk of serious side effects, and the ability to conduct usual activities while on treatment. In contrast, attributes related to treatment modalities were the least important. Respondents expressed a willingness to accept risks in hopes of finding some benefit, such as a higher chance of drug response or greater health improvement potential. Increasing disease severity, impairment or disability, and the lack of effective therapeutic options were shown to raise significantly the willingness to gain benefit through increased risk. This is the first study performing a quantitative discrete choice experiment amongst patients and caregivers across 52 rare conditions. It enables a more detailed understanding of the relationship between disease context, treatment attributes and the degree of risk respondents are willing to take to gain a specific degree of benefit. Researchers of novel therapeutics for rare diseases should be encouraged to invest in preference elicitation studies to generate rigorous patient evidence and specific regulatory guidance should be issued to acknowledge their importance and their use in marketing authorisations.

Using a discrete choice experiment to inform the design of programs to promote colon cancer screening for vulnerable populations in North Carolina.

PubMed

Pignone, Michael P; Crutchfield, Trisha M; Brown, Paul M; Hawley, Sarah T; Laping, Jane L; Lewis, Carmen L; Lich, Kristen Hassmiller; Richardson, Lisa C; Tangka, Florence Kl; Wheeler, Stephanie B

2014-11-30

Screening for colorectal cancer (CRC) is suboptimal, particularly for vulnerable populations. Effective intervention programs are needed to increase screening rates. We used a discrete choice experiment (DCE) to learn about how vulnerable individuals in North Carolina value different aspects of CRC screening programs. We enrolled English-speaking adults ages 50-75 at average risk of CRC from rural North Carolina communities with low rates of CRC screening, targeting those with public or no insurance and low incomes. Participants received basic information about CRC screening and potential program features, then completed a 16 task DCE and survey questions that examined preferences for four attributes of screening programs: testing options available; travel time required; money paid for screening or rewards for completing screening; and the portion of the cost of follow-up care paid out of pocket. We used Hierarchical Bayesian methods to calculate individual-level utilities for the 4 attributes' levels and individual-level attribute importance scores. For each individual, the attribute with the highest importance score was considered the most important attribute. Individual utilities were then aggregated to produce mean utilities for each attribute. We also compared DCE-based results with those from direct questions in a post-DCE survey. We enrolled 150 adults. Mean age was 57.8 (range 50-74); 55% were women; 76% White and 19% African-American; 87% annual household income under $30,000; and 51% were uninsured. Individuals preferred shorter travel; rewards or small copayments compared with large copayments; programs that included stool testing as an option; and greater coverage of follow-up costs. Follow-up cost coverage was most frequently found to be the most important attribute from the DCE (47%); followed by test reward/copayment (33%). From the survey, proportion of follow-up costs paid was most frequently cited as most important (42% of participants), followed by testing options (32%). There was moderate agreement (45%) in attribute importance between the DCE and the single question in the post-DCE survey. Screening test copayments and follow-up care coverage costs are important program characteristics in this vulnerable, rural population.

Understanding clinicians' decisions to offer intravenous thrombolytic treatment to patients with acute ischaemic stroke: a protocol for a discrete choice experiment.

PubMed

De Brún, Aoife; Flynn, Darren; Joyce, Kerry; Ternent, Laura; Price, Christopher; Rodgers, Helen; Ford, Gary A; Lancsar, Emily; Rudd, Matthew; Thomson, Richard G

2014-07-09

Intravenous thrombolysis is an effective emergency treatment for acute ischaemic stroke for patients meeting specific criteria. Approximately 12% of eligible patients in England, Wales and Northern Ireland received thrombolysis in the first quarter of 2013, yet as many as 15% are eligible to receive treatment. Suboptimal use of thrombolysis may have been largely attributable to structural factors; however, with the widespread implementation of 24/7 hyper acute stroke services, continuing variation is likely to reflect differences in clinical decision-making, in particular the influence of ambiguous areas within the guidelines, licensing criteria and research evidence. Clinicians' perceptions about thrombolysis may now exert a greater influence on treatment rates than structural/service factors. This research seeks to elucidate factors influencing thrombolysis decision-making by using patient vignettes to identify (1) patient-related and clinician-related factors that may help to explain variation in treatment and (2) associated trade-offs in decision-making based on the interplay of critical factors. A discrete choice experiment (DCE) will be conducted to better understand how clinicians make decisions about whether or not to offer thrombolysis to patients with acute ischaemic stroke. To inform the design, exploratory work will be undertaken to ensure that (1) all potentially influential factors are considered for inclusion; and (2) to gain insights into the 'grey areas' of patient factors. A fractional factorial design will be used to combine levels of patient factors in vignettes, which will be presented to clinicians to allow estimation of the variable effects on decisions to offer thrombolysis. Ethical approval for this study was obtained from the Newcastle University Research Ethics Committee. The results will be disseminated in peer review publications and at national conferences. Findings will be translated into continuing professional development activities and will support implementation of a computerised decision aid for thrombolysis (COMPASS) in acute stroke care. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

What factors are critical to attracting NHS foundation doctors into specialty or core training? A discrete choice experiment.

PubMed

Scanlan, Gillian Marion; Cleland, Jennifer; Johnston, Peter; Walker, Kim; Krucien, Nicolas; Skåtun, Diane

2018-03-12

Multiple personal and work-related factors influence medical trainees' career decision-making. The relative value of these diverse factors is under-researched, yet this intelligence is crucially important for informing medical workforce planning and retention and recruitment policies. Our aim was to investigate the relative value of UK doctors' preferences for different training post characteristics during the time period when they either apply for specialty or core training or take time out. We developed a discrete choice experiment (DCE) specifically for this population. The DCE was distributed to all Foundation Programme Year 2 (F2) doctors across Scotland as part of the National Career Destination Survey in June 2016. The main outcome measure was the monetary value of training post characteristics, based on willingness to forgo additional potential income and willingness to accept extra income for a change in each job characteristic calculated from regression coefficients. 677/798 F2 doctors provided usable DCE responses. Location was the most influential characteristic of a training position, followed closely by supportive culture and then working conditions. F2 doctors would need to be compensated by an additional 45.75% above potential earnings to move from a post in a desirable location to one in an undesirable location. Doctors who applied for a training post placed less value on supportive culture and excellent working conditions than those who did not apply. Male F2s valued location and a supportive culture less than female F2s. This is the first study focusing on the career decision-making of UK doctors at a critical careers decision-making point. Both location and specific job-related attributes are highly valued by F2 doctors when deciding their future. This intelligence can inform workforce policy to focus their efforts in terms of making training posts attractive to this group of doctors to enhance recruitment and retention. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

What matters in type 2 diabetes mellitus oral treatment? A discrete choice experiment to evaluate patient preferences.

PubMed

Mühlbacher, Axel; Bethge, Susanne

2016-12-01

The aim of this empirical study is to evaluate patient preferences for different characteristics of oral type 2 diabetes mellitus (T2DM) treatment. As T2DM treatment requires strict adherence, patient needs and preferences should be taken into consideration. Based on a qualitative and quantitative analysis, a discrete choice experiment (DCE) was applied to identify patient preferences. Apart from six identical attributes (adjustment of glycated hemoglobin [HbA1c], prevention of hypoglycemia, risk of genital infection, risk of gastrointestinal problems, risk of urinary tract infection, and weight change), one continuous variable of either "additional healthy life years" (AHY) or "additional costs" attribute (AC) was included. The DCE was conducted using a fractional factorial design, and the statistical data analysis used random effect logit models. In total, N = 626 (N = 318 AHY + N = 308 AC) T2DM patients participated in the survey. The estimation revealed a clear dominance for prevention of hypoglycemia (coefficient 0.937) and adjustment of HbA1c (coefficient 0.541). The attributes, "additional healthy life years" (coefficient 0.458) or "additional costs" (coefficient 0.420), were in the middle rank and both of significant impact. The side effects, risk of genital infection (coefficient 0.301), risk of gastrointestinal problems (coefficient 0.296), and risk of urinary tract infection (coefficient 0.241) followed in this respective order. Possible weight change (coefficient 0.047) was of less importance (last rank) to the patients in this evaluation. These survey results demonstrate how much a (hypothetical) T2DM oral treatment characteristic affects the treatment decision. The preference data can be used for risk-benefit assessment, cost-benefit assessment, and the establishment of patient-oriented evidence. Understanding how patients perceive and value different aspects of diabetes oral treatment is vital to the optimal design and evaluation of treatment options. The present results can be an additional source of information for design, assessment, and decision in T2DM treatment regimes. As such, more effective and efficient care of patients can be achieved, thereby increasing adherence.

Do patients and health care providers have discordant preferences about which aspects of treatments matter most? Evidence from a systematic review of discrete choice experiments.

PubMed

Harrison, Mark; Milbers, Katherine; Hudson, Marie; Bansback, Nick

2017-05-17

To review studies eliciting patient and healthcare provider preferences for healthcare interventions using discrete choice experiments (DCEs) to (1) review the methodology to evaluate similarities, differences, rigour of designs and whether comparisons are made at the aggregate level or account for individual heterogeneity; and (2) quantify the extent to which they demonstrate concordance of patient and healthcare provider preferences. A systematic review searching Medline, EMBASE, Econlit, PsycINFO and Web of Science for DCEs using patient and healthcare providers. peer-reviewed; complete empiric text in English from 1995 to 31July 2015; discussing a healthcare-related topic; DCE methodology; comparing patients and healthcare providers. Systematic review. We identified 38 papers exploring 16 interventions in 26 diseases/indications. Methods to analyse results, determine concordance between patient and physician values, and explore heterogeneity varied considerably between studies. The majority of studies we reviewed found more evidence of mixed concordance and discordance (n=28) or discordance of patient and healthcare provider preferences (n=12) than of concordant preferences (n=4). A synthesis of concordance suggested that healthcare providers rank structure and outcome attributes more highly than patients, while patients rank process attributes more highly than healthcare providers. Discordant patient and healthcare provider preferences for different attributes of healthcare interventions are common. Concordance varies according to whether attributes are processes, structures or outcomes, and therefore determining preference concordance should consider all aspects jointly and not a binary outcome. DCE studies provide excellent opportunities to assess value concordance between patients and providers, but assessment of concordance was limited by a lack of consistency in the approaches used and consideration of heterogeneity of preferences. Future DCEs assessing concordance should fully report the framing of the questions and investigate the heterogeneity of preferences within groups and how these compare. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Preferences for ARV-based HIV prevention methods among men and women, adolescent girls and female sex workers in Gauteng Province, South Africa: a protocol for a discrete choice experiment.

PubMed

Quaife, Matthew; Eakle, Robyn; Cabrera, Maria; Vickerman, Peter; Tsepe, Motlalepule; Cianci, Fiona; Delany-Moretlwe, Sinead; Terris-Prestholt, Fern

2016-06-27

For the past few decades, condoms have been the main method of HIV prevention. Recent advances in antiretroviral (ARV)-based prevention products have substantially changed the prevention landscape, yet little is known about how popular these products will be among potential users, or whether new methods might be used in conjunction with, or instead of, condoms. This study will use a discrete choice experiment (DCE) to (1) explore potential users' preferences regarding HIV prevention products, (2) quantify the importance of product attributes and (3) predict the uptake of products to inform estimates of their potential impact on the HIV epidemic in South Africa. We consider preferences for oral pre-exposure prophylaxis; a vaginal microbicide gel; a long-acting vaginal ring; a SILCS diaphragm used in concert with gel; and a long-acting ARV-based injectable. This study will gather data from 4 populations: 200 women, 200 men, 200 adolescent girls (aged 16-17 years) and 200 female sex workers. The DCE attributes and design will be developed through a literature review, supplemented by a thematic analysis of qualitative focus group discussions. Extensive piloting will be carried out in each population through semistructured interviews. The final survey will be conducted using computer tablets via a household sample (for women, men and adolescents) and respondent-driven sampling (for female sex workers), and DCE data analysed using a range of multinomial logit models. This study has been approved by the University of the Witwatersrand Human Research Ethics Committee and the Research Ethics Committee at the London School of Hygiene and Tropical Medicine. Findings will be presented to international conferences and peer-reviewed journals. Meetings will be held with opinion leaders in South Africa, while results will be disseminated to participants in Ekurhuleni through a public meeting or newsletter. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Willingness to pay for flexible working conditions of people with type 2 diabetes: discrete choice experiments.

PubMed

Nexo, M A; Cleal, B; Hagelund, Lise; Willaing, I; Olesen, K

2017-12-15

The increasing number of people with chronic diseases challenges workforce capacity. Type 2 diabetes (T2D) can have work-related consequences, such as early retirement. Laws of most high-income countries require workplaces to provide accommodations to enable people with chronic disabilities to manage their condition at work. A barrier to successful implementation of such accommodations can be lack of co-workers' willingness to support people with T2D. This study aimed to examine the willingness to pay (WTP) of people with and without T2D for five workplace initiatives that help individuals with type 2 diabetes manage their diabetes at work. Three samples with employed Danish participants were drawn from existing online panels: a general population sample (n = 600), a T2D sample (n = 693), and a matched sample of people without diabetes (n = 539). Participants completed discrete choice experiments eliciting their WTP (reduction in monthly salary, €/month) for five hypothetical workplace initiatives: part-time job, customized work, extra breaks with pay, and time off for medical consultations with and without pay. WTP was estimated by conditional logits models. Bootstrapping was used to estimate confidence intervals for WTP. There was an overall WTP for all initiatives. Average WTP for all attributes was 34 €/month (95% confidence interval [CI]: 27-43] in the general population sample, 32 €/month (95% CI: 26-38) in the T2D sample, and 55 €/month (95% CI: 43-71) in the matched sample. WTP for additional breaks with pay was considerably lower than for the other initiatives in all samples. People with T2D had significantly lower WTP than people without diabetes for part-time work, customized work, and time off without pay, but not for extra breaks or time off with pay. For people with and without T2D, WTP was present for initiatives that could improve management of diabetes at the workplace. WTP was lowest among people with T2D. Implementation of these initiatives seems feasible and may help unnecessary exclusion of people with T2D from work.

Undesirable Choice Biases with Small Differences in the Spatial Structure of Chance Stimulus Sequences.

PubMed

Herrera, David; Treviño, Mario

2015-01-01

In two-alternative discrimination tasks, experimenters usually randomize the location of the rewarded stimulus so that systematic behavior with respect to irrelevant stimuli can only produce chance performance on the learning curves. One way to achieve this is to use random numbers derived from a discrete binomial distribution to create a 'full random training schedule' (FRS). When using FRS, however, sporadic but long laterally-biased training sequences occur by chance and such 'input biases' are thought to promote the generation of laterally-biased choices (i.e., 'output biases'). As an alternative, a 'Gellerman-like training schedule' (GLS) can be used. It removes most input biases by prohibiting the reward from appearing on the same location for more than three consecutive trials. The sequence of past rewards obtained from choosing a particular discriminative stimulus influences the probability of choosing that same stimulus on subsequent trials. Assuming that the long-term average ratio of choices matches the long-term average ratio of reinforcers, we hypothesized that a reduced amount of input biases in GLS compared to FRS should lead to a reduced production of output biases. We compared the choice patterns produced by a 'Rational Decision Maker' (RDM) in response to computer-generated FRS and GLS training sequences. To create a virtual RDM, we implemented an algorithm that generated choices based on past rewards. Our simulations revealed that, although the GLS presented fewer input biases than the FRS, the virtual RDM produced more output biases with GLS than with FRS under a variety of test conditions. Our results reveal that the statistical and temporal properties of training sequences interacted with the RDM to influence the production of output biases. Thus, discrete changes in the training paradigms did not translate linearly into modifications in the pattern of choices generated by a RDM. Virtual RDMs could be further employed to guide the selection of proper training schedules for perceptual decision-making studies.

Valuing the chances of survival of two distinct Eurasian lynx populations in Poland - do people want to keep the doors open?

PubMed

Bartczak, Anna; Meyerhoff, Jürgen

2013-11-15

This study investigates individuals' preferences toward protection programs aimed at increasing the chances of survival of the two distinct Eurasian lynx populations in Poland. Those two groups, the Lowland and the Carpathian population, are exposed to different risks of extinction as they have different numbers, different-sized areas of occupation and different migration possibilities. Using a discrete choice experiment we examine the influence of the initial degree of endangerment on the allocation of respondents' funds. The results show that people prefer to invest in the conservation of the lynx population, which has initially lower chances of survival. The main driver of respondents' choices seems to be loss aversion rather than the urge to invest in an option with an expected higher outcome. This observation can be interpreted as people trying to keep all the options - doors - open by devoting more funds to the more vulnerable population than to the more stable one. Employing a scale-extended latent class model allowed us to detect segments among individuals showing different types of response behavior, including a form of serial non-participation. Copyright © 2013 Elsevier Ltd. All rights reserved.

What is clearance worth? Patients' stated risk tolerance for psoriasis treatments.

PubMed

Fairchild, Angelyn O; Reed, Shelby D; Johnson, F Reed; Anglin, Greg; Wolka, Anne M; Noel, Rebecca A

2017-12-01

The purpose of this study was to provide quantitative evidence of patients' tolerance for therapeutic risks associated with psoriasis treatments that could offer psoriasis improvements beyond the PASI 75 benchmark. We used a discrete-choice experiment in which respondents chose between competing psoriasis treatments characterized by benefits (i.e. reduced plaque severity, reduced plaque area), risks (i.e. 10-year risk of tuberculosis, 10-year risk of death from infection), and treatment regimen. We analyzed choice data using random-parameters logit models for psoriasis affecting the body, face, or hands. Of 927 eligible members of the National Psoriasis Foundation who completed the survey, 28% were unwilling to accept any greater risk of treatment-related infection mortality. Among the remaining 72%, respondents were willing to accept higher risks of infection-related mortality associated with treatment to completely remove plaques covering only 1% of the body, compared to reducing lesions from 10 to 1% of the affected area. This finding was more pronounced for lesions on the face. Most patients placed greater value on eliminating even very small plaques compared to avoiding treatment-related risks. The perceived importance of complete versus near-complete clearance was stronger than previously documented.

Consumer preferences for food allergen labeling.

PubMed

Marra, Carlo A; Harvard, Stephanie; Grubisic, Maja; Galo, Jessica; Clarke, Ann; Elliott, Susan; Lynd, Larry D

2017-01-01

Food allergen labeling is an important tool to reduce risk of exposure and prevent anaphylaxis for individuals with food allergies. Health Canada released a Canadian food allergen labeling regulation (2008) and subsequent update (2012) suggesting that research is needed to guide further iterations of the regulation to improve food allergen labeling and reduce risk of exposure. The primary objective of this study was to examine consumer preferences in food labeling for allergy avoidance and anaphylaxis prevention. A secondary objective was to identify whether different subgroups within the consumer population emerged. A discrete choice experiment using a fractional factorial design divided into ten different versions with 18 choice-sets per version was developed to examine consumer preferences for different attributes of food labeling. Three distinct subgroups of Canadian consumers with different allergen considerations and food allergen labeling needs were identified. Overall, preferences for standardized precautionary and safety symbols at little or no increased cost emerged. While three distinct groups with different preferences were identified, in general the results revealed that the current Canadian food allergen labeling regulation can be improved by enforcing the use of standardized precautionary and safety symbols and educating the public on the use of these symbols.

Free choice and career choice: Clerkship electives in medical education.

PubMed

Mihalynuk, Tanis; Leung, Gentson; Fraser, Joan; Bates, Joanna; Snadden, David

2006-11-01

Medical education experiences, particularly in clinical years, are reported determinants of career choice. Less is known about features of clinical education experiences including length, discipline, setting and choice, which may serve as landmarks in career choice decisions. This study's purpose was to explore the benefits of a free choice clerkship elective, and more specifically, its role in clarifying career choice. Using framework and content analysis methodology, we analysed University of British Columbia, third-year medical student anonymised assignments regarding free choice and 2-week clerkship elective experiences. This clerkship was designed to provide students with clerkship experiences outside the conventional curricular model, while encouraging student choice of ambulatory and community settings. Assignment questions included: reasons for choosing elective; whether learning objectives were met; influence of elective on career choice; and unique elective experiences. Iterative review, coding, analysis and indexing of assignments were carried out to identify themes and corroborate findings. Emergent themes included: positive views of experience; transferable knowledge and skills; and influencer of future education and career choices. Although students were encouraged to choose clerkship experiences outside the conventional curricular model, most students chose the elective to clarify future career decisions. This qualitative descriptive study highlights the influence of highly regarded, free choice clerkship elective experiences in the career decision making process in medical education. Further examination of the details of clerkship elective experiences which influence career choice is recommended.

Using the Nobel Laureates in Economics to Teach Quantitative Methods

ERIC Educational Resources Information Center

Becker, William E.; Greene, William H.

2005-01-01

The authors show how the work of Nobel Laureates in economics can enhance student understanding and bring them up to date on topics such as probability, uncertainty and decision theory, hypothesis testing, regression to the mean, instrumental variable techniques, discrete choice modeling, and time-series analysis. (Contains 2 notes.)

Japanese Children's Reasoning about Conflicts with Parents

ERIC Educational Resources Information Center

Yamada, Hiroyuki

2009-01-01

Ninety-five Japanese children (aged 6-12) were interviewed using hypothetical stories to examine their reasoning about parent-child conflicts. Participants were most likely to reject parental authority and to support child's discretion in conflict situations where the parent interfered in the child's personal choice and gave the child commands…

Welfare Reform when Recipients Are Forward-Looking

ERIC Educational Resources Information Center

Swann, Christopher A.

2005-01-01

By studying recipients of aid under the Temporary Assistance for Needy Families (TANF) welfare scheme, the effect of time limits of welfare schemes on forward looking recipients is assessed using a discrete-choice dynamic programming framework model. The policy simulations for the preferred specification of utility reveal that two year time limits…

Strategic planning for national security: Lessons from business experience. Interim report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bracken, P.

1990-02-01

United States defense planning is at a crossroads and it is therefore useful to review not only discrete issues, but even basic concepts of strategic planning. This Note reviews concepts used in the business world to build insights about how to view current and prospective problems, opportunities, and choices. The author draws upon the business literature for both ideas and metaphors. He observes that U.S. national security planning could profit greatly from an approach that distinguishes among core, environmental, and hedging strategies, and that considers security analogs to such business concepts as defining the business, dealing with new competitors, controllingmore » the intensity of competition, entry and exit barriers, and the need to redeploy assets and restructure the organization. He then relates these concepts to specific problems of national security interest.« less

The excess choice effect: The role of outcome valence and counterfactual thinking.

PubMed

Hafner, Rebecca J; White, Mathew P; Handley, Simon J

2016-02-01

Contrary to economic theory, psychological research has demonstrated increased choice can undermine satisfaction. When and why this 'excess choice effect' (ECE) occurs remains unclear. Building on theories of counterfactual thinking we argue the ECE is more likely to occur when people experience counterfactual thought or emotion and that a key trigger is a negative versus positive task outcome. Participants either selected a drink (Experiment 1) or chocolate (Experiment 2) from a limited (6) versus extensive (24) selection (Experiment 1) or were given no choice versus extensive (24) choice (Experiment 2). In both experiments, however, the choice was illusory: Half the participants tasted a 'good' flavour, half a 'bad' flavour. As predicted, extensive choice was only detrimental to satisfaction when participants tasted the 'bad' drink or chocolate, and this was mediated by the experience of counterfactual thought (Experiment 1) or emotion (Experiment 2). When outcomes were positive, participants were similarly satisfied with limited versus extensive and no choice versus extensive choice. Implications for our theoretical understanding of the ECE and for the construction of choice architectures aimed at promoting individual satisfaction and well-being are discussed. © 2015 The British Psychological Society.

Physician and patient willingness to pay for electronic cardiovascular disease management.

PubMed

Deal, Ken; Keshavjee, Karim; Troyan, Sue; Kyba, Robert; Holbrook, Anne Marie

2014-07-01

Cardiovascular disease (CVD) is an important target for electronic decision support. We examined the potential sustainability of an electronic CVD management program using a discrete choice experiment (DCE). Our objective was to estimate physician and patient willingness-to-pay (WTP) for the current and enhanced programs. Focus groups, expert input and literature searches decided the attributes to be evaluated for the physician and patient DCEs, which were carried out using a Web-based program. Hierarchical Bayes analysis estimated preference coefficients for each respondent and latent class analysis segmented each sample. Simulations were used to estimate WTP for each of the attributes individually and for an enhanced vascular management system. 144 participants (70 physicians, 74 patients) completed the DCE. Overall, access speed to updated records and monthly payments for a nurse coordinator were the main determinants of physician choices. Two distinctly different segments of physicians were identified - one very sensitive to monthly subscription fee and speed of updating the tracker with new patient data and the other very sensitive to the monthly cost of the nurse coordinator and government billing incentives. Patient choices were most significantly influenced by the yearly subscription cost. The estimated physician WTP was slightly above the estimated threshold for sustainability while the patient WTP was below. Current willingness to pay for electronic cardiovascular disease management should encourage innovation to provide economies of scale in program development, delivery and maintenance to meet sustainability thresholds. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

CONSUMER PREFERENCES FOR SCANNING MODALITY TO DIAGNOSE FOCAL LIVER LESIONS.

PubMed

Whitty, Jennifer; Filby, Alexandra; Smith, Adam B; Carr, Louise M

2015-01-01

Differences in the process of using liver imaging technologies might be important to patients. This study aimed to investigate preferences for scanning modalities used in diagnosing focal liver lesions. A discrete choice experiment was administered to 504 adults aged 25 ≥years. Respondents made repeated choices between two hypothetical scans, described according to waiting time for scan and results, procedure type, the chance of minor side-effects, and whether further scanning procedures were likely to be required. Choice data were analyzed using mixed-logit models with respondent characteristics used to explain preference heterogeneity. Respondents preferred shorter waiting times, the procedure to be undertaken with a handheld scanner on a couch instead of within a body scanner, no side-effects, and no follow–up scans (p≤.01). The average respondent was willing to wait an additional 2 weeks for the scan if it resulted in avoiding side-effects, 1.5 weeks to avoid further procedures or to be told the results immediately, and 1 week to have the scan performed on a couch with a handheld scanner. However, substantial heterogeneity was observed in the strength of preference for desirable imaging characteristics. An average individual belonging to a general population sub–group most likely to require imaging to characterize focal liver lesions in the United Kingdom would prefer contrast–enhanced ultrasound over magnetic resonance imaging or computed tomography. Insights into the patient perspective around differential characteristics of imaging modalities have the potential to be used to guide recommendations around the use of these technologie

Cognitive Judgment Bias Interacts with Risk Based Decision Making and Sensitivity to Dopaminergic Challenge in Male Rats

PubMed Central

Drozd, Robert; Cieslak, Przemyslaw E.; Rychlik, Michal; Rodriguez Parkitna, Jan; Rygula, Rafal

2016-01-01

Although the cognitive theory has implicated judgment bias in various psychopathologies, its role in decision making under risk remains relatively unexplored. In the present study, we assessed the effects of cognitive judgment bias on risky choices in rats. First, we trained and tested the animals on the rat version of the probability-discounting (PD) task. During discrete trials, the rats chose between two levers; a press on the “small/certain” lever always resulted in the delivery of one reward pellet, whereas a press on the “large/risky” lever resulted in the delivery of four pellets. However, the probability of receiving a reward from the “large/risky” lever gradually decreased over the four trial blocks. Subsequently, the rats were re-trained and evaluated on a series of ambiguous-cue interpretation (ACI) tests, which permitted their classification according to the display of “optimistic” or “pessimistic” traits. Because dopamine (DA) has been implicated in both: risky choices and optimism, in the last experiment, we compared the reactivity of the dopaminergic system in the “optimistic” and “pessimistic” animals using the apomorphine (APO; 2 mg/kg s.c.) sensitivity test. We demonstrated that as risk increased, the proportion of risky lever choices decreased significantly slower in “optimists” compared with “pessimists” and that these differences between the two groups of rats were associated with different levels of dopaminergic system reactivity. Our findings suggest that cognitive judgment bias, risky decision-making and DA are linked, and they provide a foundation for further investigation of the behavioral traits and cognitive processes that influence risky choices in animal models. PMID:27601984

Impact of Treatment Subsidies and Cash Payouts on Treatment Choices at the End of Life.

PubMed

Finkelstein, Eric; Malhotra, Chetna; Chay, Junxing; Ozdemir, Semra; Chopra, Akhil; Kanesvaran, Ravindran

To examine the extent to which financial assistance, in the form of subsidies for life-extending treatments (LETs) or cash payouts, distorts the demand for end-of-life treatments. A discrete choice experiment was administered to 290 patients with cancer in Singapore to elicit preferences for LETs and only palliative care (PC). Responses were fitted to a latent class conditional logistic regression model. We also quantified patients' willingness to pay to avoid and willingness to accept a less effective LET or PC-only. We then simulated the effects of various LET subsidy and cash payout policies on treatment choices. We identified three classes of patients according to their preferences. The first class (26.1% of the sample) had a strong preference for PC and were willing to give up life expectancy gains and even pay for receiving only PC. The second class (29.8% of the sample) had a strong preference for LETs and preferred to extend life regardless of cost or quality of life. The final class (44.1% of the sample) preferred LETs to PC, but actively traded off costs and length and quality of life when making end-of-life treatment choices. Policy simulations showed that LET subsidies increase demand for LETs at the expense of demand for PC, but an equivalent cash payout was not shown to distort demand. Patients with cancer have heterogeneous end-of-life preferences. LET subsidies and cash payouts have differing effects on the use of LETs. Policymakers should be mindful of these differences when designing health care financing schemes for patients with life-limiting illnesses. Copyright © 2016. Published by Elsevier Inc.

Using the animal to the last bit: Consumer preferences for different beef cuts.

PubMed

Scozzafava, Gabriele; Corsi, Armando Maria; Casini, Leonardo; Contini, Caterina; Loose, Simone Mueller

2016-01-01

Meat is expensive to produce, making it is essential to understand the importance consumers pay to different meat cuts. Previous research on consumers' meat choices has mainly focused on meat species, while consumer preferences for meat cuts has so far only received limited interest. The aim of this study is to shed some light into this relatively unexplored area by answering four research questions. First, this study intends to show the relative importance meat cuts play in relation to other extrinsic product attributes. Secondly, this paper looks into differences in choice criteria between regular and special occasions. Third, consumer segments that differ in their preferences and beef purchase are identified, and, finally, the meat purchase portfolios of these segments are revealed. A stated preference methodology of a discrete choice experiment with cut-specific prices covering several meat cuts simultaneously is proposed to answer the research questions. The sample consists of 1500 respondents representative of the Italian population in terms of age, gender and geographic location The results shows that meat cut is the most important factor when choosing bovine meat followed by quality certification (origin), production technique, the type of breed and price. In terms of consumption occasions, we observe significantly lower price sensitivity for marbled steaks and cutlets for special occasions compared to normal occasions. Segmentation analysis shows that while the choices of two segments (comprising about 40% of the sample) are mostly driven by extrinsic product attributes, the remaining segments are mostly driven by meat cuts. These varying preferences are also reflected in the purchase portfolios of the different segments, while less variability is detected from a socio-demographic perspective. Copyright © 2015 Elsevier Ltd. All rights reserved.

Genetic Algorithms for Multiple-Choice Problems

NASA Astrophysics Data System (ADS)

Aickelin, Uwe

2010-04-01

This thesis investigates the use of problem-specific knowledge to enhance a genetic algorithm approach to multiple-choice optimisation problems.It shows that such information can significantly enhance performance, but that the choice of information and the way it is included are important factors for success.Two multiple-choice problems are considered.The first is constructing a feasible nurse roster that considers as many requests as possible.In the second problem, shops are allocated to locations in a mall subject to constraints and maximising the overall income.Genetic algorithms are chosen for their well-known robustness and ability to solve large and complex discrete optimisation problems.However, a survey of the literature reveals room for further research into generic ways to include constraints into a genetic algorithm framework.Hence, the main theme of this work is to balance feasibility and cost of solutions.In particular, co-operative co-evolution with hierarchical sub-populations, problem structure exploiting repair schemes and indirect genetic algorithms with self-adjusting decoder functions are identified as promising approaches.The research starts by applying standard genetic algorithms to the problems and explaining the failure of such approaches due to epistasis.To overcome this, problem-specific information is added in a variety of ways, some of which are designed to increase the number of feasible solutions found whilst others are intended to improve the quality of such solutions.As well as a theoretical discussion as to the underlying reasons for using each operator,extensive computational experiments are carried out on a variety of data.These show that the indirect approach relies less on problem structure and hence is easier to implement and superior in solution quality.

Does Introducing Imprecision around Probabilities for Benefit and Harm Influence the Way People Value Treatments?

PubMed

Bansback, Nick; Harrison, Mark; Marra, Carlo

2016-05-01

Imprecision in estimates of benefits and harms around treatment choices is rarely described to patients. Variation in sampling error between treatment alternatives (e.g., treatments have similar average risks, but one treatment has a larger confidence interval) can result in patients failing to choose the option that is best for them. The aim of this study is to use a discrete choice experiment to describe how 2 methods for conveying imprecision in risk influence people's treatment decisions. We randomized a representative sample of the Canadian general population to 1 of 3 surveys that sought choices between hypothetical treatments for rheumatoid arthritis based on different levels of 7 attributes: route and frequency of administration, chance of benefit, serious and minor side effects and life expectancy, and imprecision in benefit and side-effect estimates. The surveys differed in the way imprecision was described: 1) no imprecision, 2) quantitative description based on a range with a visual graphic, and 3) qualitative description simply describing the confidence in the evidence. The analyzed data were from 2663 respondents. Results suggested that more people understood imprecision when it was described qualitatively (88%) versus quantitatively (68%). Respondents who appeared to understand imprecision descriptions placed high value on increased precision regarding the actual benefits and harms of treatment, equivalent to the value placed on the information about the probability of serious side effects. Both qualitative and quantitative methods led to small but significant increases in decision uncertainty for choosing any treatment. Limitations included some issues in defining understanding of imprecision and the use of an internet survey of panel members. These findings provide insight into how conveying imprecision information influences patient treatment choices. © The Author(s) 2015.

Effect of terminal accuracy requirements on temporal gaze-hand coordination during fast discrete and reciprocal pointings

PubMed Central

2011-01-01

Background Rapid discrete goal-directed movements are characterized by a well known coordination pattern between the gaze and the hand displacements. The gaze always starts prior to the hand movement and reaches the target before hand velocity peak. Surprisingly, the effect of the target size on the temporal gaze-hand coordination has not been directly investigated. Moreover, goal-directed movements are often produced in a reciprocal rather than in a discrete manner. The objectives of this work were to assess the effect of the target size on temporal gaze-hand coordination during fast 1) discrete and 2) reciprocal pointings. Methods Subjects performed fast discrete (experiment 1) and reciprocal (experiment 2) pointings with an amplitude of 50 cm and four target diameters (7.6, 3.8, 1.9 and 0.95 cm) leading to indexes of difficulty (ID = log2[2A/D]) of 3.7, 4.7, 5.7 and 6.7 bits. Gaze and hand displacements were synchronously recorded. Temporal gaze-hand coordination parameters were compared between experiments (discrete and reciprocal pointings) and IDs using analyses of variance (ANOVAs). Results Data showed that the magnitude of the gaze-hand lead pattern was much higher for discrete than for reciprocal pointings. Moreover, while it was constant for discrete pointings, it decreased systematically with an increasing ID for reciprocal pointings because of the longer duration of gaze anchoring on target. Conclusion Overall, the temporal gaze-hand coordination analysis revealed that even for high IDs, fast reciprocal pointings could not be considered as a concatenation of discrete units. Moreover, our data clearly illustrate the smooth adaptation of temporal gaze-hand coordination to terminal accuracy requirements during fast reciprocal pointings. It will be interesting for further researches to investigate if the methodology used in the experiment 2 allows assessing the effect of sensori-motor deficits on gaze-hand coordination. PMID:21320315

24 CFR 982.315 - Family break-up.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 24 Housing and Urban Development 4 2011-04-01 2011-04-01 false Family break-up. 982.315 Section... SECTION 8 TENANT BASED ASSISTANCE: HOUSING CHOICE VOUCHER PROGRAM Leasing a Unit § 982.315 Family break-up. (a)(1) The PHA has discretion to determine which members of an assisted family continue to receive...

Learner Flexibility Profiles. Coombe Lodge Working Paper. Information Bank Number 1612.

ERIC Educational Resources Information Center

Latcham, J.; Spencer, D. C.

To help in the exploration of developments in increasing learning flexibility in Great Britain's further education system, this paper suggests the development of learner flexibility profiles as devices for analyzing and recording the nature and extent of student choice or discretion. The introductory section reviews developments in open learning…

Empirical methods for modeling landscape change, ecosystem services, and biodiversity

Treesearch

David Lewis; Ralph Alig

2009-01-01

The purpose of this paper is to synthesize recent economics research aimed at integrating discrete-choice econometric models of land-use change with spatially-explicit landscape simulations and quantitative ecology. This research explicitly models changes in the spatial pattern of landscapes in two steps: 1) econometric estimation of parcel-scale transition...

Scale of harvesting by non-industrial private forest landowners

Treesearch

Melinda Vokoun; Gregory S. Amacher; David N. Wear

2006-01-01

We examine the intensity of harvesting decision by non-industrial landowners at the lowest price offer they deem acceptable, using a multiple bounded discrete choice stated preference approach that draws upon and connects two subfields of forestry, one identifying characteristics of landowners important to past harvesting or reforestation decisions, and another...

Learning large-scale dynamic discrete choice models of spatio-temporal preferences with application to migratory pastoralism in East Africa

USDA-ARS?s Scientific Manuscript database

Understanding spatio-temporal resource preferences is paramount in the design of policies for sustainable development. Unfortunately, resource preferences are often unknown to policy-makers and have to be inferred from data. In this paper we consider the problem of inferring agents’ preferences fro...

24 CFR 982.315 - Family break-up.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Family break-up. 982.315 Section... SECTION 8 TENANT BASED ASSISTANCE: HOUSING CHOICE VOUCHER PROGRAM Leasing a Unit § 982.315 Family break-up. (a) The PHA has discretion to determine which members of an assisted family continue to receive...

The European Union and the Comprehensive Civil-Military Approach in Euro-Atlantic Security: Matching Reality to Rhetoric

DTIC Science & Technology

2010-01-01

aspects below the political PSC level. This practically guaranteed inco - herence and disunity as an institutional inheritance. Second, and equally as...central point of emphasis that “defense and diplomacy are no longer discrete choices . . . but must complement one another throughout the messy process

Is Accessing of Words Affected by Affective Valence Only? A Discrete Emotion View on the Emotional Congruency Effect

PubMed Central

Chen, Xuqian; Liu, Bo; Lin, Shouwen

2016-01-01

This paper advances the discussion on which emotion information affects word accessing. Emotion information, which is formed as a result of repeated experiences, is primary and necessary in learning and representing word meanings. Previous findings suggested that valence (i.e., positive or negative) denoted by words can be automatically activated and plays a role in many significant cognitive processes. However, there has been a lack of discussion about whether discrete emotion information (i.e., happiness, anger, sadness, and fear) is also involved in these processes. According to the hierarchy model, emotions are considered organized within an abstract-to-concrete hierarchy, in which emotion prototypes are organized following affective valence. By controlling different congruencies of emotion relations (i.e., matches or mismatches between valences and prototypes of emotion), the present study showed both an evaluative congruency effect (Experiment 1) and a discrete emotional congruency effect (Experiment 2). These findings indicate that not only affective valences but also discrete emotions can be activated under the present priming lexical decision task. However, the present findings also suggest that discrete emotions might be activated at the later priming stage as compared to valences. The present work provides evidence that information about discrete emotion could be involved in word processing. This might be a result of subjects’ embodied experiences. PMID:27379000

Is Accessing of Words Affected by Affective Valence Only? A Discrete Emotion View on the Emotional Congruency Effect.

PubMed

Chen, Xuqian; Liu, Bo; Lin, Shouwen

2016-01-01

This paper advances the discussion on which emotion information affects word accessing. Emotion information, which is formed as a result of repeated experiences, is primary and necessary in learning and representing word meanings. Previous findings suggested that valence (i.e., positive or negative) denoted by words can be automatically activated and plays a role in many significant cognitive processes. However, there has been a lack of discussion about whether discrete emotion information (i.e., happiness, anger, sadness, and fear) is also involved in these processes. According to the hierarchy model, emotions are considered organized within an abstract-to-concrete hierarchy, in which emotion prototypes are organized following affective valence. By controlling different congruencies of emotion relations (i.e., matches or mismatches between valences and prototypes of emotion), the present study showed both an evaluative congruency effect (Experiment 1) and a discrete emotional congruency effect (Experiment 2). These findings indicate that not only affective valences but also discrete emotions can be activated under the present priming lexical decision task. However, the present findings also suggest that discrete emotions might be activated at the later priming stage as compared to valences. The present work provides evidence that information about discrete emotion could be involved in word processing. This might be a result of subjects' embodied experiences.

MEDICAL EXPENDITURE RISK AND HOUSEHOLD PORTFOLIO CHOICE

PubMed Central

Goldman, Dana

2013-01-01

Medical expenses are an increasingly important contributor to household financial risk. We examine the effect of medical expenditure risk on the willingness of Medicare beneficiaries to hold risky assets. Using a discrete factor maximum likelihood method to address the endogeneity of insurance choices, we find that having a moderately protective Medigap or employer supplemental policy increases risky asset holding by 7.1 percentage points relative to those without supplemental coverage, while participation in a highly protective Medicare HMO increases risky asset holding by 13.0 percentage points. Our results highlight an important link between the availability of health insurance and financial behavior. PMID:23997424

The Pasinetti-Solow Growth Model with Optimal Saving Behaviour: A Local Bifurcation Analysis

NASA Astrophysics Data System (ADS)

Commendatore, P.; Palmisani, C.

We present a discrete time version of the Pasinetti-Solow economic growth model. Workers and capitalists are assumed to save on the basis of rational choices. Workers face a finite time horizon and base their consumption choices on a life-cycle motive, whereas capitalists behave like an infinitely-lived dynasty. The accumulation of both capitalists' and workers' wealth through time is reduced to a two-dimensional map whose local asymptotic stability properties are studied. Various types of bifurcation emerge (flip, Neimark-Sacker, saddle-node and transcritical): a precondition for chaotic dynamics.

A Kronecker product splitting preconditioner for two-dimensional space-fractional diffusion equations

NASA Astrophysics Data System (ADS)

Chen, Hao; Lv, Wen; Zhang, Tongtong

2018-05-01

We study preconditioned iterative methods for the linear system arising in the numerical discretization of a two-dimensional space-fractional diffusion equation. Our approach is based on a formulation of the discrete problem that is shown to be the sum of two Kronecker products. By making use of an alternating Kronecker product splitting iteration technique we establish a class of fixed-point iteration methods. Theoretical analysis shows that the new method converges to the unique solution of the linear system. Moreover, the optimal choice of the involved iteration parameters and the corresponding asymptotic convergence rate are computed exactly when the eigenvalues of the system matrix are all real. The basic iteration is accelerated by a Krylov subspace method like GMRES. The corresponding preconditioner is in a form of a Kronecker product structure and requires at each iteration the solution of a set of discrete one-dimensional fractional diffusion equations. We use structure preserving approximations to the discrete one-dimensional fractional diffusion operators in the action of the preconditioning matrix. Numerical examples are presented to illustrate the effectiveness of this approach.

Lens elliptic gamma function solution of the Yang-Baxter equation at roots of unity

NASA Astrophysics Data System (ADS)

Kels, Andrew P.; Yamazaki, Masahito

2018-02-01

We study the root of unity limit of the lens elliptic gamma function solution of the star-triangle relation, for an integrable model with continuous and discrete spin variables. This limit involves taking an elliptic nome to a primitive rNth root of unity, where r is an existing integer parameter of the lens elliptic gamma function, and N is an additional integer parameter. This is a singular limit of the star-triangle relation, and at subleading order of an asymptotic expansion, another star-triangle relation is obtained for a model with discrete spin variables in {Z}rN . Some special choices of solutions of equation of motion are shown to result in well-known discrete spin solutions of the star-triangle relation. The saddle point equations themselves are identified with three-leg forms of ‘3D-consistent’ classical discrete integrable equations, known as Q4 and Q3(δ=0) . We also comment on the implications for supersymmetric gauge theories, and in particular comment on a close parallel with the works of Nekrasov and Shatashvili.

Kink dynamics in a topological φ4 lattice

NASA Astrophysics Data System (ADS)

Adib, A. B.; Almeida, C. A. S.

2001-09-01

Recently proposed was a discretization for nonlinear Klein-Gordon field theories in which the resulting lattice preserves the topological (Bogomol'nyi) lower bound on the kink energy and, as a consequence, has no Peierls-Nabarro barrier even for large spatial discretizations (h~1.0). It was then suggested that these ``topological discrete systems'' are a natural choice for the numerical study of continuum kink dynamics. Giving particular emphasis to the φ4 theory, we numerically investigate kink-antikink scattering and breather formation in these topological lattices. Our results indicate that, even though these systems are quite accurate for studying free kinks in coarse lattices, for legitimate dynamical kink problems the accuracy is rather restricted to fine lattices (h~0.1). We suggest that this fact is related to the breaking of the Bogomol'nyi bound during the kink-antikink interaction, where the field profile loses its static property as required by the Bogomol'nyi argument. We conclude, therefore, that these lattices are not suitable for the study of more general kink dynamics, since a standard discretization is simpler and has effectively the same accuracy for such resolutions.