The case-control design in veterinary sciences: A survey.
Cullen, Jonah N; Sargeant, Jan M; Makielski, Kelly M; O'Connor, Annette M
2016-11-01
The case-control study design is deceptively simple. However, many design considerations influence the estimated effect measure. An investigation of case-control studies in the human health literature suggested that some of these considerations are not described in reports of case-control studies. Our hypothesis was that the majority of veterinary studies labeled as case-controls would be incident density designs, and many would not interpret the effect measure obtained from those studies as the rate ratio rather than the odds ratio. Reference databases were searched for author-designated case-control studies. A survey of 100 randomly selected studies was conducted to examine the different design options described and estimated effect measures. Of the 100 author-identified case-control studies, 83 assessed an exposure-outcome association and, of those, only 54 (65.1%) sampled the study population based on an outcome and would thus be considered case-control designs. Twelve studies were incidence density designs but none used this terminology. Of the studies that reported an odds ratio as the effect measure, none reported on additional considerations that would have enabled a more interpretable result. This survey indicated many case-control-labeled studies were not case-control designs and among case-control studies, key design aspects were not often described. The absence of information about study design elements and underlying assumptions in case-control studies limits the ability to establish the effect measured by the study and the evidentiary value of the study might be underestimated. Copyright © 2016 Elsevier B.V. All rights reserved.
Henk, Henry J; Li, Xiaoyan; Becker, Laura K; Xu, Hairong; Gong, Qi; Deeter, Robert G; Barron, Richard L
2015-01-01
To examine the impact of research design on results in two published comparative effectiveness studies. Guidelines for comparative effectiveness research have recommended incorporating disease process in study design. Based on the recommendations, we develop a checklist of considerations and apply the checklist in review of two published studies on comparative effectiveness of colony-stimulating factors. Both studies used similar administrative claims data, but different methods, which resulted in directionally different estimates. Major design differences between the two studies include: whether the timing of intervention in disease process was identified and whether study cohort and outcome assessment period were defined based on this temporal relationship. Disease process and timing of intervention should be incorporated into the design of comparative effectiveness studies.
The Minicommunity Design to Assess Indirect Effects of Vaccination.
Halloran, M Elizabeth
2012-08-01
We propose the minicommunity design to estimate indirect effects of vaccination. Establishing indirect effects of vaccination in unvaccinated subpopulations could have important implications for global vaccine policies. In the minicommunity design, the household or other small transmission unit serves as the cluster in which to estimate indirect effects of vaccination, similar to studies in larger communities to estimate indirect, total, and overall effects. Examples from the literature include studies in small transmission units to estimate indirect effects of pertussis, pneumococcal, influenza, and cholera vaccines. We characterize the minicommunity design by several methodologic considerations, including the assignment mechanism, ascertainment, the role of transmission outside the transmission unit, and the relation of the size of the transmission unit to number of people vaccinated. The minicommunity study for indirect effects is contrasted with studies to estimate vaccine effects on infectiousness and protective effects under conditions of household exposure within small transmission units. The minicommunity design can be easily implemented in individually randomized studies by enrolling and following-up members of households of the randomized individuals. The methodology for the minicommunity design for estimating indirect effects of vaccination deserves much future research.
The effects of design details on cost and weight of fuselage structures
NASA Technical Reports Server (NTRS)
Swanson, G. D.; Metschan, S. L.; Morris, M. R.; Kassapoglou, C.
1993-01-01
Crown panel design studies showing the relationship between panel size, cost, weight, and aircraft configuration are compared to aluminum design configurations. The effects of a stiffened sandwich design concept are also discussed. This paper summarizes the effect of a design cost model in assessing the cost and weight relationships for fuselage crown panel designs. Studies were performed using data from existing aircraft to assess the effects of different design variables on the cost and weight of transport fuselage crown panel design. Results show a strong influence of load levels, panel size, and material choices on the cost and weight of specific designs. A design tool being developed under the NASA ACT program is used in the study to assess these issues. The effects of panel configuration comparing postbuckled and buckle resistant stiffened laminated structure is compared to a stiffened sandwich concept. Results suggest some potential economy with stiffened sandwich designs for compression dominated structure with relatively high load levels.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-07-01
... on the Experimental Study of Comparative Direct-to-Consumer (DTC) Advertising. This study is designed... indirect comparisons, using comparative visuals, and using vaguer language. This study is designed to apply... Effectiveness) studies designed to explore comparative effectiveness. When this large project is completed, FDA...
Escalator Design Features Evaluation
DOT National Transportation Integrated Search
1982-05-01
This study provides an evaluation of the effectiveness of several special design features associated with escalators in rail transit systems. The objective of the study was to evaluate the effectiveness of three escalator design features: (1) mat ope...
Statistical power calculations for mixed pharmacokinetic study designs using a population approach.
Kloprogge, Frank; Simpson, Julie A; Day, Nicholas P J; White, Nicholas J; Tarning, Joel
2014-09-01
Simultaneous modelling of dense and sparse pharmacokinetic data is possible with a population approach. To determine the number of individuals required to detect the effect of a covariate, simulation-based power calculation methodologies can be employed. The Monte Carlo Mapped Power method (a simulation-based power calculation methodology using the likelihood ratio test) was extended in the current study to perform sample size calculations for mixed pharmacokinetic studies (i.e. both sparse and dense data collection). A workflow guiding an easy and straightforward pharmacokinetic study design, considering also the cost-effectiveness of alternative study designs, was used in this analysis. Initially, data were simulated for a hypothetical drug and then for the anti-malarial drug, dihydroartemisinin. Two datasets (sampling design A: dense; sampling design B: sparse) were simulated using a pharmacokinetic model that included a binary covariate effect and subsequently re-estimated using (1) the same model and (2) a model not including the covariate effect in NONMEM 7.2. Power calculations were performed for varying numbers of patients with sampling designs A and B. Study designs with statistical power >80% were selected and further evaluated for cost-effectiveness. The simulation studies of the hypothetical drug and the anti-malarial drug dihydroartemisinin demonstrated that the simulation-based power calculation methodology, based on the Monte Carlo Mapped Power method, can be utilised to evaluate and determine the sample size of mixed (part sparsely and part densely sampled) study designs. The developed method can contribute to the design of robust and efficient pharmacokinetic studies.
Techniques for Conducting Effective Concept Design and Design-to-Cost Trade Studies
NASA Technical Reports Server (NTRS)
Di Pietro, David A.
2015-01-01
Concept design plays a central role in project success as its product effectively locks the majority of system life cycle cost. Such extraordinary leverage presents a business case for conducting concept design in a credible fashion, particularly for first-of-a-kind systems that advance the state of the art and that have high design uncertainty. A key challenge, however, is to know when credible design convergence has been achieved in such systems. Using a space system example, this paper characterizes the level of convergence needed for concept design in the context of technical and programmatic resource margins available in preliminary design and highlights the importance of design and cost evaluation learning curves in determining credible convergence. It also provides techniques for selecting trade study cases that promote objective concept evaluation, help reveal unknowns, and expedite convergence within the trade space and conveys general practices for conducting effective concept design-to-cost studies.
Evaluating Effectiveness of a Frigate in an Anti-Air Warfare (AAW) Environment
2016-06-01
missions to accomplish. Both studies are used in ship design to determine the ship’s required combat capabilities before finalizing the hull design. This...accomplish. Both studies are used in ship design to determine the ship’s required combat capabilities before finalizing the hull design. This...capabilities should be determined before the ship’s hull design is complete to make operational effectiveness independent from physical design considerations
Boessen, Ruud; van der Baan, Frederieke; Groenwold, Rolf; Egberts, Antoine; Klungel, Olaf; Grobbee, Diederick; Knol, Mirjam; Roes, Kit
2013-01-01
Two-stage clinical trial designs may be efficient in pharmacogenetics research when there is some but inconclusive evidence of effect modification by a genomic marker. Two-stage designs allow to stop early for efficacy or futility and can offer the additional opportunity to enrich the study population to a specific patient subgroup after an interim analysis. This study compared sample size requirements for fixed parallel group, group sequential, and adaptive selection designs with equal overall power and control of the family-wise type I error rate. The designs were evaluated across scenarios that defined the effect sizes in the marker positive and marker negative subgroups and the prevalence of marker positive patients in the overall study population. Effect sizes were chosen to reflect realistic planning scenarios, where at least some effect is present in the marker negative subgroup. In addition, scenarios were considered in which the assumed 'true' subgroup effects (i.e., the postulated effects) differed from those hypothesized at the planning stage. As expected, both two-stage designs generally required fewer patients than a fixed parallel group design, and the advantage increased as the difference between subgroups increased. The adaptive selection design added little further reduction in sample size, as compared with the group sequential design, when the postulated effect sizes were equal to those hypothesized at the planning stage. However, when the postulated effects deviated strongly in favor of enrichment, the comparative advantage of the adaptive selection design increased, which precisely reflects the adaptive nature of the design. Copyright © 2013 John Wiley & Sons, Ltd.
ERIC Educational Resources Information Center
Yuruk, Nejla; Beeth, Michael E.; Andersen, Christopher
2009-01-01
This study investigated the effect of metaconceptual teaching interventions on students' understanding of force and motion concepts. A multimethod research design including quasi-experimental design and case study designs was employed to compare the effect of the metaconceptual activities and traditional instruction and investigate students'…
A powerful test for Balaam's design.
Mori, Joji; Kano, Yutaka
2015-01-01
The crossover trial design (AB/BA design) is often used to compare the effects of two treatments in medical science because it performs within-subject comparisons, which increase the precision of a treatment effect (i.e., a between-treatment difference). However, the AB/BA design cannot be applied in the presence of carryover effects and/or treatments-by-period interaction. In such cases, Balaam's design is a more suitable choice. Unlike the AB/BA design, Balaam's design inflates the variance of an estimate of the treatment effect, thereby reducing the statistical power of tests. This is a serious drawback of the design. Although the variance of parameter estimators in Balaam's design has been extensively studied, the estimators of the treatment effect to improve the inference have received little attention. If the estimate of the treatment effect is obtained by solving the mixed model equations, the AA and BB sequences are excluded from the estimation process. In this study, we develop a new estimator of the treatment effect and a new test statistic using the estimator. The aim is to improve the statistical inference in Balaam's design. Simulation studies indicate that the type I error of the proposed test is well controlled, and that the test is more powerful and has more suitable characteristics than other existing tests when interactions are substantial. The proposed test is also applied to analyze a real dataset. Copyright © 2015 John Wiley & Sons, Ltd.
Factors in Human-Computer Interface Design (A Pilot Study).
1994-12-01
This study used a pretest - posttest control group experimental design to test the effect of consistency on speed, retention, and user satisfaction. Four...analysis. The overall methodology was a pretest - posttest control group experimental design using different prototypes to test the effects of...methodology used for this study was a pretest - posttest control group experimental design using different prototypes to test for features of the human
Zeng, Yaohui; Singh, Sachinkumar; Wang, Kai
2017-01-01
Abstract Pharmacodynamic studies that use methacholine challenge to assess bioequivalence of generic and innovator albuterol formulations are generally designed per published Food and Drug Administration guidance, with 3 reference doses and 1 test dose (3‐by‐1 design). These studies are challenging and expensive to conduct, typically requiring large sample sizes. We proposed 14 modified study designs as alternatives to the Food and Drug Administration–recommended 3‐by‐1 design, hypothesizing that adding reference and/or test doses would reduce sample size and cost. We used Monte Carlo simulation to estimate sample size. Simulation inputs were selected based on published studies and our own experience with this type of trial. We also estimated effects of these modified study designs on study cost. Most of these altered designs reduced sample size and cost relative to the 3‐by‐1 design, some decreasing cost by more than 40%. The most effective single study dose to add was 180 μg of test formulation, which resulted in an estimated 30% relative cost reduction. Adding a single test dose of 90 μg was less effective, producing only a 13% cost reduction. Adding a lone reference dose of either 180, 270, or 360 μg yielded little benefit (less than 10% cost reduction), whereas adding 720 μg resulted in a 19% cost reduction. Of the 14 study design modifications we evaluated, the most effective was addition of both a 90‐μg test dose and a 720‐μg reference dose (42% cost reduction). Combining a 180‐μg test dose and a 720‐μg reference dose produced an estimated 36% cost reduction. PMID:29281130
Stratton, Shawna L; Henrich, Cindy L; Matthews, Nell I; Bogusiewicz, Anna; Dawson, Amanda M; Horvath, Thomas D; Owen, Suzanne N; Boysen, Gunnar; Moran, Jeffery H; Mock, Donald M
2012-01-01
To date, marginal, asymptomatic biotin deficiency has been successfully induced experimentally by the use of labor-intensive inpatient designs requiring rigorous dietary control. We sought to determine if marginal biotin deficiency could be induced in humans in a less expensive outpatient design incorporating a self-selected, mixed general diet. We sought to examine the efficacy of three outpatient study designs: two based on oral avidin dosing and one based on a diet high in undenatured egg white for a period of 28 d. In study design 1, participants (n = 4; 3 women) received avidin in capsules with a biotin binding capacity of 7 times the estimated dietary biotin intake of a typical self-selected diet. In study design 2, participants (n = 2; 2 women) received double the amount of avidin capsules (14 times the estimated dietary biotin intake). In study design 3, participants (n = 5; 3 women) consumed egg-white beverages containing avidin with a biotin binding capacity of 7 times the estimated dietary biotin intake. Established indices of biotin status [lymphocyte propionyl-CoA carboxylase activity; urinary excretion of 3-hydroxyisovaleric acid, 3-hydroxyisovaleryl carnitine (3HIA-carnitine), and biotin; and plasma concentration of 3HIA-carnitine] indicated that study designs 1 and 2 were not effective in inducing marginal biotin deficiency, but study design 3 was as effective as previous inpatient study designs that induced deficiency by egg-white beverage. Marginal biotin deficiency can be induced experimentally by using a cost-effective outpatient design by avidin delivery in egg-white beverages. This design should be useful to the broader nutritional research community.
ERIC Educational Resources Information Center
Alias, Norlidah; Siraj, Saedah; Daud, Mohd Khairul Azman Md; Hussin, Zaharah
2013-01-01
The study examines the effectiveness of Facebook based learning to enhance creativity among Islamic Studies students in the secondary educational setting in Malaysia. It describes the design process by employing the Isman Instructional Design Model. A quantitative study was carried out using experimental method and background survey. The…
Recommendations for research design of telehealth studies.
Chumbler, Neale R; Kobb, Rita; Brennan, David M; Rabinowitz, Terry
2008-11-01
Properly designed randomized controlled trials (RCTs) are the gold standard to use when examining the effectiveness of telehealth interventions on clinical outcomes. Some published telehealth studies have employed well-designed RCTs. However, such methods are not always feasible and practical in particular settings. This white paper addresses not only the need for properly designed RCTs, but also offers alternative research designs, such as quasi-experimental designs, and statistical techniques that can be employed to rigorously assess the effectiveness of telehealth studies. This paper further offers design and measurement recommendations aimed at and relevant to administrative decision-makers, policymakers, and practicing clinicians.
NASA Astrophysics Data System (ADS)
Nash, A. E., III
2017-12-01
The most common approaches to identifying the most effective mission design to maximize science return from a potential set of competing alternative design approaches are often inefficient and inaccurate. Recently, Team-X at the Jet Propulsion Laboratory undertook an effort to improve both the speed and quality of science - measurement - mission design trade studies. We will report on the methodology & processes employed and their effectiveness in trade study speed and quality. Our results indicate that facilitated subject matter expert peers are the keys to speed and quality improvements in the effectiveness of science - measurement - mission design trade studies.
Designing Effective Safety Signs, Based on a Study of Recall for Safety Signs.
ERIC Educational Resources Information Center
Berry, Dennis W.
Aside from direct supervision at a recreational facility, safety signs, if designed properly, are the most effective approach to facility safety. This study was conducted to investigate the effectiveness of various sign designs: (l) multiple concepts with text; (2) single concept with text; and (3) single concept with graphics. A discussion of…
ERIC Educational Resources Information Center
Crits-Christoph, Paul; Mintz, Jim
1991-01-01
Presents reasons therapist should be included as random design factor in nested analysis of (co)variance (AN[C]OVA) design used in psychotherapy research. Reviews studies which indicate majority of investigators ignore issue of effects from incorrect specification of ANOVA design. Presents reanalysis of data from 10 psychotherapy outcome studies…
The Single-Group, Pre- and Posttest Design in Nursing Education Research: It's Time to Move on.
Spurlock, Darrell R
2018-02-01
Studying the effectiveness of educational interventions is centrally important to building the science of nursing education. Yet, the design most commonly used in the study of nursing education interventions-the single-group, preand posttest design-provides limited evidence to support claims of intervention effectiveness. In this Methodology Corner installment, the limitations of the single-group, preand posttest design are outlined and a review of the requirements for establishing stronger arguments for causality is presented. To overcome the limitations of single-group, preand posttest designs, nursing education researchers are encouraged to employ study designs and procedures that can significantly strengthen researchers' claims of intervention effectiveness. [J Nurs Educ. 2018;57(2):69-71.]. Copyright 2018, SLACK Incorporated.
Anglemyer, Andrew; Horvath, Hacsi T; Bero, Lisa
2014-04-29
Researchers and organizations often use evidence from randomized controlled trials (RCTs) to determine the efficacy of a treatment or intervention under ideal conditions. Studies of observational designs are often used to measure the effectiveness of an intervention in 'real world' scenarios. Numerous study designs and modifications of existing designs, including both randomized and observational, are used for comparative effectiveness research in an attempt to give an unbiased estimate of whether one treatment is more effective or safer than another for a particular population.A systematic analysis of study design features, risk of bias, parameter interpretation, and effect size for all types of randomized and non-experimental observational studies is needed to identify specific differences in design types and potential biases. This review summarizes the results of methodological reviews that compare the outcomes of observational studies with randomized trials addressing the same question, as well as methodological reviews that compare the outcomes of different types of observational studies. To assess the impact of study design (including RCTs versus observational study designs) on the effect measures estimated.To explore methodological variables that might explain any differences identified.To identify gaps in the existing research comparing study designs. We searched seven electronic databases, from January 1990 to December 2013.Along with MeSH terms and relevant keywords, we used the sensitivity-specificity balanced version of a validated strategy to identify reviews in PubMed, augmented with one term ("review" in article titles) so that it better targeted narrative reviews. No language restrictions were applied. We examined systematic reviews that were designed as methodological reviews to compare quantitative effect size estimates measuring efficacy or effectiveness of interventions tested in trials with those tested in observational studies. Comparisons included RCTs versus observational studies (including retrospective cohorts, prospective cohorts, case-control designs, and cross-sectional designs). Reviews were not eligible if they compared randomized trials with other studies that had used some form of concurrent allocation. In general, outcome measures included relative risks or rate ratios (RR), odds ratios (OR), hazard ratios (HR). Using results from observational studies as the reference group, we examined the published estimates to see whether there was a relative larger or smaller effect in the ratio of odds ratios (ROR).Within each identified review, if an estimate comparing results from observational studies with RCTs was not provided, we pooled the estimates for observational studies and RCTs. Then, we estimated the ratio of ratios (risk ratio or odds ratio) for each identified review using observational studies as the reference category. Across all reviews, we synthesized these ratios to get a pooled ROR comparing results from RCTs with results from observational studies. Our initial search yielded 4406 unique references. Fifteen reviews met our inclusion criteria; 14 of which were included in the quantitative analysis.The included reviews analyzed data from 1583 meta-analyses that covered 228 different medical conditions. The mean number of included studies per paper was 178 (range 19 to 530).Eleven (73%) reviews had low risk of bias for explicit criteria for study selection, nine (60%) were low risk of bias for investigators' agreement for study selection, five (33%) included a complete sample of studies, seven (47%) assessed the risk of bias of their included studies,Seven (47%) reviews controlled for methodological differences between studies,Eight (53%) reviews controlled for heterogeneity among studies, nine (60%) analyzed similar outcome measures, and four (27%) were judged to be at low risk of reporting bias.Our primary quantitative analysis, including 14 reviews, showed that the pooled ROR comparing effects from RCTs with effects from observational studies was 1.08 (95% confidence interval (CI) 0.96 to 1.22). Of 14 reviews included in this analysis, 11 (79%) found no significant difference between observational studies and RCTs. One review suggested observational studies had larger effects of interest, and two reviews suggested observational studies had smaller effects of interest.Similar to the effect across all included reviews, effects from reviews comparing RCTs with cohort studies had a pooled ROR of 1.04 (95% CI 0.89 to 1.21), with substantial heterogeneity (I(2) = 68%). Three reviews compared effects of RCTs and case-control designs (pooled ROR: 1.11 (95% CI 0.91 to 1.35)).No significant difference in point estimates across heterogeneity, pharmacological intervention, or propensity score adjustment subgroups were noted. No reviews had compared RCTs with observational studies that used two of the most common causal inference methods, instrumental variables and marginal structural models. Our results across all reviews (pooled ROR 1.08) are very similar to results reported by similarly conducted reviews. As such, we have reached similar conclusions; on average, there is little evidence for significant effect estimate differences between observational studies and RCTs, regardless of specific observational study design, heterogeneity, or inclusion of studies of pharmacological interventions. Factors other than study design per se need to be considered when exploring reasons for a lack of agreement between results of RCTs and observational studies. Our results underscore that it is important for review authors to consider not only study design, but the level of heterogeneity in meta-analyses of RCTs or observational studies. A better understanding of how these factors influence study effects might yield estimates reflective of true effectiveness.
Stratton, Shawna L.; Henrich, Cindy L.; Matthews, Nell I.; Bogusiewicz, Anna; Dawson, Amanda M.; Horvath, Thomas D.; Owen, Suzanne N.; Boysen, Gunnar; Moran, Jeffery H.; Mock, Donald M.
2012-01-01
To date, marginal, asymptomatic biotin deficiency has been successfully induced experimentally by the use of labor-intensive inpatient designs requiring rigorous dietary control. We sought to determine if marginal biotin deficiency could be induced in humans in a less expensive outpatient design incorporating a self-selected, mixed general diet. We sought to examine the efficacy of three outpatient study designs: two based on oral avidin dosing and one based on a diet high in undenatured egg white for a period of 28 d. In study design 1, participants (n = 4; 3 women) received avidin in capsules with a biotin binding capacity of 7 times the estimated dietary biotin intake of a typical self-selected diet. In study design 2, participants (n = 2; 2 women) received double the amount of avidin capsules (14 times the estimated dietary biotin intake). In study design 3, participants (n = 5; 3 women) consumed egg-white beverages containing avidin with a biotin binding capacity of 7 times the estimated dietary biotin intake. Established indices of biotin status [lymphocyte propionyl-CoA carboxylase activity; urinary excretion of 3-hydroxyisovaleric acid, 3-hydroxyisovaleryl carnitine (3HIA-carnitine), and biotin; and plasma concentration of 3HIA-carnitine] indicated that study designs 1 and 2 were not effective in inducing marginal biotin deficiency, but study design 3 was as effective as previous inpatient study designs that induced deficiency by egg-white beverage. Marginal biotin deficiency can be induced experimentally by using a cost-effective outpatient design by avidin delivery in egg-white beverages. This design should be useful to the broader nutritional research community. PMID:22157538
Development of an end-of-life vehicle recovery model using system dynamics and future research needs
NASA Astrophysics Data System (ADS)
Mohamad-Ali, N.; Ghazilla, R. A. R.; Abdul-Rashid, S. H.; Sakundarini, N.; Ahmad-Yazid, A.; Stephenie, L.
2017-06-01
The implementation of end-of-life vehicle (ELV) recovery policy in Malaysia has led vehicle manufacturers to look at different ways to improve design and development of vehicles. Nowadays, it is crucial to incorporate end-of-life (EOL) design strategies into the vehicle design in order to enhance the effectiveness of the ELV recovery network. Although recent studies have shown that product design has a significant effect on the product recovery rate, there is a lack of studies on how EOL design strategies affects the effectiveness of ELV recovery, particularly when there are dynamic changes in the behaviour of the product recovery network. Thus, in this study, we developed a preliminary model based on the system dynamics approach in order to predict the effectiveness of ELV recovery in response to dynamic changes of various factors (including EOL design strategies) in the business environment. We developed this model based on preliminary data that we had gathered from unstructured interviews with the key stakeholders of ELV management in Malaysia. We believe that our model will greatly benefit product designers in incorporating the appropriate EOL design strategies in order to boost ELV recovery effectiveness in Malaysia.
Gu, C; Rao, D C
2001-01-01
Because simplistic designs will lead to prohibitively large sample sizes, the optimization of genetic study designs is critical for successfully mapping genes for complex diseases. Creative designs are necessary for detecting and amplifying the usually weak signals for complex traits. Two important outcomes of a study design--power and resolution--are implicitly tied together by the principle of uncertainty. Overemphasis on either one may lead to suboptimal designs. To achieve optimality for a particular study, therefore, practical measures such as cost-effectiveness must be used to strike a balance between power and resolution. In this light, the myriad of factors involved in study design can be checked for their effects on the ultimate outcomes, and the popular existing designs can be sorted into building blocks that may be useful for particular situations. It is hoped that imaginative construction of novel designs using such building blocks will lead to enhanced efficiency in finding genes for complex human traits.
Active-comparator design and new-user design in observational studies
Yoshida, Kazuki; Solomon, Daniel H.; Kim, Seoyoung C.
2015-01-01
SUMMARY Over the past decade, an increasing number of observational studies have examined the effectiveness or safety of rheumatoid arthritis treatments. However, unlike randomized controlled trials (RCTs), observational studies of drug effects face methodological challenges including confounding by indication. Two design principles - active comparator design and new user design can help mitigate such challenges in observational studies. To improve validity of study findings, observational studies should be designed in such a way that makes them more closely approximate RCTs. The active comparator design compares the drug of interest to another commonly used agent for the same indication, rather than a ‘non-user’ group. This principle helps select treatment groups similar in treatment indications (both measured and unmeasured characteristics). The new user design includes a cohort of patients from the time of treatment initiation, so that it can assess patients’ pretreatment characteristics and capture all events occurring anytime during follow-up. PMID:25800216
A standardized mean difference effect size for multiple baseline designs across individuals.
Hedges, Larry V; Pustejovsky, James E; Shadish, William R
2013-12-01
Single-case designs are a class of research methods for evaluating treatment effects by measuring outcomes repeatedly over time while systematically introducing different condition (e.g., treatment and control) to the same individual. The designs are used across fields such as behavior analysis, clinical psychology, special education, and medicine. Emerging standards for single-case designs have focused attention on methods for summarizing and meta-analyzing findings and on the need for effect sizes indices that are comparable to those used in between-subjects designs. In the previous work, we discussed how to define and estimate an effect size that is directly comparable to the standardized mean difference often used in between-subjects research based on the data from a particular type of single-case design, the treatment reversal or (AB)(k) design. This paper extends the effect size measure to another type of single-case study, the multiple baseline design. We propose estimation methods for the effect size and its variance, study the estimators using simulation, and demonstrate the approach in two applications. Copyright © 2013 John Wiley & Sons, Ltd.
Quasi-experimental study designs series-paper 9: collecting data from quasi-experimental studies.
Aloe, Ariel M; Becker, Betsy Jane; Duvendack, Maren; Valentine, Jeffrey C; Shemilt, Ian; Waddington, Hugh
2017-09-01
To identify variables that must be coded when synthesizing primary studies that use quasi-experimental designs. All quasi-experimental (QE) designs. When designing a systematic review of QE studies, potential sources of heterogeneity-both theory-based and methodological-must be identified. We outline key components of inclusion criteria for syntheses of quasi-experimental studies. We provide recommendations for coding content-relevant and methodological variables and outlined the distinction between bivariate effect sizes and partial (i.e., adjusted) effect sizes. Designs used and controls used are viewed as of greatest importance. Potential sources of bias and confounding are also addressed. Careful consideration must be given to inclusion criteria and the coding of theoretical and methodological variables during the design phase of a synthesis of quasi-experimental studies. The success of the meta-regression analysis relies on the data available to the meta-analyst. Omission of critical moderator variables (i.e., effect modifiers) will undermine the conclusions of a meta-analysis. Copyright © 2017 Elsevier Inc. All rights reserved.
Cook, David A; Hamstra, Stanley J; Brydges, Ryan; Zendejas, Benjamin; Szostek, Jason H; Wang, Amy T; Erwin, Patricia J; Hatala, Rose
2013-01-01
Although technology-enhanced simulation is increasingly used in health professions education, features of effective simulation-based instructional design remain uncertain. Evaluate the effectiveness of instructional design features through a systematic review of studies comparing different simulation-based interventions. We systematically searched MEDLINE, EMBASE, CINAHL, ERIC, PsycINFO, Scopus, key journals, and previous review bibliographies through May 2011. We included original research studies that compared one simulation intervention with another and involved health professions learners. Working in duplicate, we evaluated study quality and abstracted information on learners, outcomes, and instructional design features. We pooled results using random effects meta-analysis. From a pool of 10,903 articles we identified 289 eligible studies enrolling 18,971 trainees, including 208 randomized trials. Inconsistency was usually large (I2 > 50%). For skills outcomes, pooled effect sizes (positive numbers favoring the instructional design feature) were 0.68 for range of difficulty (20 studies; p < 0.001), 0.68 for repetitive practice (7 studies; p = 0.06), 0.66 for distributed practice (6 studies; p = 0.03), 0.65 for interactivity (89 studies; p < 0.001), 0.62 for multiple learning strategies (70 studies; p < 0.001), 0.52 for individualized learning (59 studies; p < 0.001), 0.45 for mastery learning (3 studies; p = 0.57), 0.44 for feedback (80 studies; p < 0.001), 0.34 for longer time (23 studies; p = 0.005), 0.20 for clinical variation (16 studies; p = 0.24), and -0.22 for group training (8 studies; p = 0.09). These results confirm quantitatively the effectiveness of several instructional design features in simulation-based education.
Castellucci, H I; Arezes, P M; Molenbroek, J F M; de Bruin, R; Viviani, C
2017-01-01
The purpose of this study was to determine, using a systematic review, whether the design and/or dimensions of school furniture affect the students' physical responses and/or their performance. Of the review studies, 64% presented positive results, i.e. proven effects; 24% presented negative effects or no change/effect; and the remaining 12% showed an unclear effect. The compatibility between school furniture dimensions and students' anthropometric characteristics was identified as a key factor for improving some students' physical responses. Design characteristics such as high furniture, sit-stand furniture, and tilt tables and seats also present positive effects. Finally, we concluded that further research should be conducted exploring various aspects of those variables, particularly focusing on more objective measures complemented by controlled and prospective design. Practitioner Summary: A systematic review of the literature presents a clearly positive effect of school furniture dimensions on students' performance and physical responses. Similar results appeared when school furniture design was tested. However, studying the effects of design and dimensions together produced an unclear positive effect.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Newman, Ken
1997-06-01
Experiment designs to estimate the effect of transportation on survival and return rates of Columbia River system salmonids are discussed along with statistical modeling techniques. Besides transportation, river flow and dam spill are necessary components in the design and analysis otherwise questions as to the effects of reservoir drawdowns and increased dam spill may never be satisfactorily answered. Four criteria for comparing different experiment designs are: (1) feasibility, (2) clarity of results, (3) scope of inference, and (4) time to learn. In this report, alternative designs for conducting experimental manipulations of smolt tagging studies to study effects of river operationsmore » such as flow levels, spill fractions, and transporting outmigrating salmonids around dams in the Columbia River system are presented. The principles of study design discussed in this report have broad implications for the many studies proposed to investigate both smolt and adult survival relationships. The concepts are illustrated for the case of the design and analysis of smolt transportation experiments. The merits of proposed transportation studies should be measured relative to these principles of proper statistical design and analysis.« less
Zeng, Yaohui; Singh, Sachinkumar; Wang, Kai; Ahrens, Richard C
2018-04-01
Pharmacodynamic studies that use methacholine challenge to assess bioequivalence of generic and innovator albuterol formulations are generally designed per published Food and Drug Administration guidance, with 3 reference doses and 1 test dose (3-by-1 design). These studies are challenging and expensive to conduct, typically requiring large sample sizes. We proposed 14 modified study designs as alternatives to the Food and Drug Administration-recommended 3-by-1 design, hypothesizing that adding reference and/or test doses would reduce sample size and cost. We used Monte Carlo simulation to estimate sample size. Simulation inputs were selected based on published studies and our own experience with this type of trial. We also estimated effects of these modified study designs on study cost. Most of these altered designs reduced sample size and cost relative to the 3-by-1 design, some decreasing cost by more than 40%. The most effective single study dose to add was 180 μg of test formulation, which resulted in an estimated 30% relative cost reduction. Adding a single test dose of 90 μg was less effective, producing only a 13% cost reduction. Adding a lone reference dose of either 180, 270, or 360 μg yielded little benefit (less than 10% cost reduction), whereas adding 720 μg resulted in a 19% cost reduction. Of the 14 study design modifications we evaluated, the most effective was addition of both a 90-μg test dose and a 720-μg reference dose (42% cost reduction). Combining a 180-μg test dose and a 720-μg reference dose produced an estimated 36% cost reduction. © 2017, The Authors. The Journal of Clinical Pharmacology published by Wiley Periodicals, Inc. on behalf of American College of Clinical Pharmacology.
The incident user design in comparative effectiveness research.
Johnson, Eric S; Bartman, Barbara A; Briesacher, Becky A; Fleming, Neil S; Gerhard, Tobias; Kornegay, Cynthia J; Nourjah, Parivash; Sauer, Brian; Schumock, Glen T; Sedrakyan, Art; Stürmer, Til; West, Suzanne L; Schneeweiss, Sebastian
2013-01-01
Comparative effectiveness research includes cohort studies and registries of interventions. When investigators design such studies, how important is it to follow patients from the day they initiated treatment with the study interventions? Our article considers this question and related issues to start a dialogue on the value of the incident user design in comparative effectiveness research. By incident user design, we mean a study that sets the cohort's inception date according to patients' new use of an intervention. In contrast, most epidemiologic studies enroll patients who were currently or recently using an intervention when follow-up began. We take the incident user design as a reasonable default strategy because it reduces biases that can impact non-randomized studies, especially when investigators use healthcare databases. We review case studies where investigators have explored the consequences of designing a cohort study by restricting to incident users, but most of the discussion has been informed by expert opinion, not by systematic evidence. Published 2012. This article is a U.S. Government work and is in the public domain in the USA.
Diaz, Francisco J; Berg, Michel J; Krebill, Ron; Welty, Timothy; Gidal, Barry E; Alloway, Rita; Privitera, Michael
2013-12-01
Due to concern and debate in the epilepsy medical community and to the current interest of the US Food and Drug Administration (FDA) in revising approaches to the approval of generic drugs, the FDA is currently supporting ongoing bioequivalence studies of antiepileptic drugs, the EQUIGEN studies. During the design of these crossover studies, the researchers could not find commercial or non-commercial statistical software that quickly allowed computation of sample sizes for their designs, particularly software implementing the FDA requirement of using random-effects linear models for the analyses of bioequivalence studies. This article presents tables for sample-size evaluations of average bioequivalence studies based on the two crossover designs used in the EQUIGEN studies: the four-period, two-sequence, two-formulation design, and the six-period, three-sequence, three-formulation design. Sample-size computations assume that random-effects linear models are used in bioequivalence analyses with crossover designs. Random-effects linear models have been traditionally viewed by many pharmacologists and clinical researchers as just mathematical devices to analyze repeated-measures data. In contrast, a modern view of these models attributes an important mathematical role in theoretical formulations in personalized medicine to them, because these models not only have parameters that represent average patients, but also have parameters that represent individual patients. Moreover, the notation and language of random-effects linear models have evolved over the years. Thus, another goal of this article is to provide a presentation of the statistical modeling of data from bioequivalence studies that highlights the modern view of these models, with special emphasis on power analyses and sample-size computations.
NASA Astrophysics Data System (ADS)
Rieben, James C., Jr.
This study focuses on the effects of relevance and lab design on student learning within the chemistry laboratory environment. A general chemistry conductivity of solutions experiment and an upper level organic chemistry cellulose regeneration experiment were employed. In the conductivity experiment, the two main variables studied were the effect of relevant (or "real world") samples on student learning and a verification-based lab design versus a discovery-based lab design. With the cellulose regeneration experiment, the effect of a discovery-based lab design vs. a verification-based lab design was the sole focus. Evaluation surveys consisting of six questions were used at three different times to assess student knowledge of experimental concepts. In the general chemistry laboratory portion of this study, four experimental variants were employed to investigate the effect of relevance and lab design on student learning. These variants consisted of a traditional (or verification) lab design, a traditional lab design using "real world" samples, a new lab design employing real world samples/situations using unknown samples, and the new lab design using real world samples/situations that were known to the student. Data used in this analysis were collected during the Fall 08, Winter 09, and Fall 09 terms. For the second part of this study a cellulose regeneration experiment was employed to investigate the effects of lab design. A demonstration creating regenerated cellulose "rayon" was modified and converted to an efficient and low-waste experiment. In the first variant students tested their products and verified a list of physical properties. In the second variant, students filled in a blank physical property chart with their own experimental results for the physical properties. Results from the conductivity experiment show significant student learning of the effects of concentration on conductivity and how to use conductivity to differentiate solution types with the use of real world samples. In the organic chemistry experiment, results suggest that the discovery-based design improved student retention of the chain length differentiation by physical properties relative to the verification-based design.
Sullivan, Sheena G.; Tchetgen Tchetgen, Eric J.; Cowling, Benjamin J.
2016-01-01
Influenza viruses undergo frequent antigenic changes. As a result, the viruses circulating change within and between seasons, and the composition of the influenza vaccine is updated annually. Thus, estimation of the vaccine's effectiveness is not constant across seasons. In order to provide annual estimates of the influenza vaccine's effectiveness, health departments have increasingly adopted the “test-negative design,” using enhanced data from routine surveillance systems. In this design, patients presenting to participating general practitioners with influenza-like illness are swabbed for laboratory testing; those testing positive for influenza virus are defined as cases, and those testing negative form the comparison group. Data on patients' vaccination histories and confounder profiles are also collected. Vaccine effectiveness is estimated from the odds ratio comparing the odds of testing positive for influenza among vaccinated patients and unvaccinated patients, adjusting for confounders. The test-negative design is purported to reduce bias associated with confounding by health-care-seeking behavior and misclassification of cases. In this paper, we use directed acyclic graphs to characterize potential biases in studies of influenza vaccine effectiveness using the test-negative design. We show how studies using this design can avoid or minimize bias and where bias may be introduced with particular study design variations. PMID:27587721
The Effects of Model Making on Design and Learning in Landscape Architecture Education
ERIC Educational Resources Information Center
Duzenli, Tugba; Yilmaz, Serap; Alpak, Elif Merve
2017-01-01
Purpose: One of the modeling methods used in the training of all design disciplines is physical model making. This study investigates the model-making technique and emphasizes the positive effects of model-making and its utility in the academic setting in order to understand its effects on design and learning. The "Equipment Design"…
Designing Studies That Would Address the Multilayered Nature of Health Care
Pennell, Michael; Rhoda, Dale; Hade, Erinn M.; Paskett, Electra D.
2010-01-01
We review design and analytic methods available for multilevel interventions in cancer research with particular attention to study design, sample size requirements, and potential to provide statistical evidence for causal inference. The most appropriate methods will depend on the stage of development of the research and whether randomization is possible. Early on, fractional factorial designs may be used to screen intervention components, particularly when randomization of individuals is possible. Quasi-experimental designs, including time-series and multiple baseline designs, can be useful once the intervention is designed because they require few sites and can provide the preliminary evidence to plan efficacy studies. In efficacy and effectiveness studies, group-randomized trials are preferred when randomization is possible and regression discontinuity designs are preferred otherwise if assignment based on a quantitative score is possible. Quasi-experimental designs may be used, especially when combined with recent developments in analytic methods to reduce bias in effect estimates. PMID:20386057
Relation between experimental and non-experimental study designs. HB vaccines: a case study
Jefferson, T.; Demicheli, V.
1999-01-01
STUDY OBJECTIVE: To examine the relation between experimental and non- experimental study design in vaccinology. DESIGN: Assessment of each study design's capability of testing four aspects of vaccine performance, namely immunogenicity (the capacity to stimulate the immune system), duration of immunity conferred, incidence and seriousness of side effects, and number of infections prevented by vaccination. SETTING: Experimental and non-experimental studies on hepatitis B (HB) vaccines in the Cochrane Vaccines Field Database. RESULTS: Experimental and non-experimental vaccine study designs are frequently complementary but some aspects of vaccine quality can only be assessed by one of the types of study. More work needs to be done on the relation between study quality and its significance in terms of effect size. PMID:10326054
Desktop Publishing: The Effects of Computerized Formats on Reading Speed and Comprehension.
ERIC Educational Resources Information Center
Knupfer, Nancy Nelson; McIsaac, Marina Stock
1989-01-01
Describes study that was conducted to determine the effects of two electronic text variables used in desktop publishing on undergraduate students' reading speed and comprehension. Research on text variables, graphic design, instructional text design, and computer screen design is discussed, and further studies are suggested. (22 references) (LRW)
29 CFR 1607.14 - Technical standards for validity studies.
Code of Federal Regulations, 2011 CFR
2011-07-01
... in the design of the study and their effects identified. (5) Statistical relationships. The degree of...; or such factors should be included in the design of the study and their effects identified. (f... arduous effort involving a series of research studies, which include criterion related validity studies...
29 CFR 1607.14 - Technical standards for validity studies.
Code of Federal Regulations, 2013 CFR
2013-07-01
... in the design of the study and their effects identified. (5) Statistical relationships. The degree of...; or such factors should be included in the design of the study and their effects identified. (f... arduous effort involving a series of research studies, which include criterion related validity studies...
29 CFR 1607.14 - Technical standards for validity studies.
Code of Federal Regulations, 2014 CFR
2014-07-01
... in the design of the study and their effects identified. (5) Statistical relationships. The degree of...; or such factors should be included in the design of the study and their effects identified. (f... arduous effort involving a series of research studies, which include criterion related validity studies...
29 CFR 1607.14 - Technical standards for validity studies.
Code of Federal Regulations, 2012 CFR
2012-07-01
... in the design of the study and their effects identified. (5) Statistical relationships. The degree of...; or such factors should be included in the design of the study and their effects identified. (f... arduous effort involving a series of research studies, which include criterion related validity studies...
29 CFR 1607.14 - Technical standards for validity studies.
Code of Federal Regulations, 2010 CFR
2010-07-01
... in the design of the study and their effects identified. (5) Statistical relationships. The degree of...; or such factors should be included in the design of the study and their effects identified. (f... arduous effort involving a series of research studies, which include criterion related validity studies...
A survey of student opinions on ethical design standards in Taiwan.
Lee, Yingying; You, Manlai; Yang, Ming-Ying
2015-04-01
Design ethics has been offered as a course in undergraduate design programs in Taiwan for over a decade, but research on teaching design ethics and the results of teaching these courses is scant. We conducted two tests to examine (1) the effect of an ethics course, and (2) the differences among the effects of design department, gender, and study year on student opinions regarding ethical design standards (EDSs) at the National Yunlin University of Science and Technology (YunTech) in Taiwan. The participants comprised 934 undergraduates (660 women and 274 men) from the five design departments at YunTech's College of Design from Years 1-4. The results confirmed the effect of an ethics course on student EDS opinions. In addition, we observed significant variations among students according to design departments, suggesting that the characteristics of the design departments also affected students' EDS opinions. The results indicated that gender did not significantly affect design students' EDS opinions; however, students in their early years of study produced higher scores than those in their advanced years of study did, based on the six EDS opinions. The implications of these results for teaching design ethics and future research are discussed in this paper.
NASA Technical Reports Server (NTRS)
Metschan, Stephen L.; Wilden, Kurtis S.; Sharpless, Garrett C.; Andelman, Rich M.
1993-01-01
Textile manufacturing processes offer potential cost and weight advantages over traditional composite materials and processes for transport fuselage elements. In the current study, design cost modeling relationships between textile processes and element design details were developed. Such relationships are expected to help future aircraft designers to make timely decisions on the effect of design details and overall configurations on textile fabrication costs. The fundamental advantage of a design cost model is to insure that the element design is cost effective for the intended process. Trade studies on the effects of processing parameters also help to optimize the manufacturing steps for a particular structural element. Two methods of analyzing design detail/process cost relationships developed for the design cost model were pursued in the current study. The first makes use of existing databases and alternative cost modeling methods (e.g. detailed estimating). The second compares design cost model predictions with data collected during the fabrication of seven foot circumferential frames for ATCAS crown test panels. The process used in this case involves 2D dry braiding and resin transfer molding of curved 'J' cross section frame members having design details characteristic of the baseline ATCAS crown design.
Becker, Betsy Jane; Aloe, Ariel M; Duvendack, Maren; Stanley, T D; Valentine, Jeffrey C; Fretheim, Atle; Tugwell, Peter
2017-09-01
To outline issues of importance to analytic approaches to the synthesis of quasi-experiments (QEs) and to provide a statistical model for use in analysis. We drew on studies of statistics, epidemiology, and social-science methodology to outline methods for synthesis of QE studies. The design and conduct of QEs, effect sizes from QEs, and moderator variables for the analysis of those effect sizes were discussed. Biases, confounding, design complexities, and comparisons across designs offer serious challenges to syntheses of QEs. Key components of meta-analyses of QEs were identified, including the aspects of QE study design to be coded and analyzed. Of utmost importance are the design and statistical controls implemented in the QEs. Such controls and any potential sources of bias and confounding must be modeled in analyses, along with aspects of the interventions and populations studied. Because of such controls, effect sizes from QEs are more complex than those from randomized experiments. A statistical meta-regression model that incorporates important features of the QEs under review was presented. Meta-analyses of QEs provide particular challenges, but thorough coding of intervention characteristics and study methods, along with careful analysis, should allow for sound inferences. Copyright © 2017 Elsevier Inc. All rights reserved.
Evaluating hospital design from an operations management perspective.
Vos, Leti; Groothuis, Siebren; van Merode, Godefridus G
2007-12-01
This paper describes an evaluation method for the assessment of hospital building design from the viewpoint of operations management to assure that the building design supports the efficient and effective operating of care processes now and in the future. The different steps of the method are illustrated by a case study. In the case study an experimental design is applied to assess the effect of used logistical concepts, patient mix and technologies. The study shows that the evaluation method provides a valuable tool for the assessment of both functionality and the ability to meet future developments in operational control of a building design.
Naik, Sandhya P; Punathil, Sameer; Shetty, Praveena; Jayanti, Ipsita; Jalaluddin, Md; Avijeeta, Anisha
2018-02-01
The aim of the present study was to evaluate the effectiveness of different bristle designs of toothbrushes and the periodontal status among patients undergoing fixed orthodontic treatment. This randomized controlled trial (RCT) consisted of 45 adolescents (comprising 20 males and 25 females) undergoing fixed orthodontic treatment. The study participants were randomly allocated to three groups, each group being assigned a locally available toothbrush with a particular design of toothbrush bristle. In the first test phase, group I study participants were allocated to toothbrush with flat bristles, group II study subjects were allocated to toothbrush with zigzag bristles, and group III study participants were allocated to toothbrush with crisscross bristles. The study participants were recalled after 4 weeks to check the effectiveness of the allocated toothbrushes. A washout period of 1 week was maintained to ensure that there was no carryover effect of the different bristle designs. In the second test phase, each patient used the opposite toothbrush bristle design (group I: toothbrush with zigzag bristles, group II: toothbrush with crisscross bristles, and group III: toothbrush with flat bristles). Plaque scores were measured using Turesky-Gilmore-Glickman modification of Quigley-Hein plaque index (PI). In both phase 1 and 2 of this RCT, toothbrush with crisscross bristles exhibited maximum plaque reduction among the three different bristle design toothbrushes following 30 days (p = 0.312 ± 0.102 and 0.280 ± 0.110, respectively), which was statistically significant. It was concluded that all the three designs of toothbrushes were effective in removing plaque in patients with fixed orthodontic appliances. But among the three different toothbrushes, toothbrush with crisscross bristles showed the highest mean plaque reduction. Plaque accumulation around the orthodontic brackets and gingival margins is quite common among the fixed orthodontic patients, who encounter difficulty in maintaining good oral hygiene. Specially designed toothbrushes are very essential for effective plaque removal among the patients undergoing fixed orthodontic treatment.
Chang, Joonho; Moon, Seung Ki; Jung, Kihyo; Kim, Wonmo; Parkinson, Matthew; Freivalds, Andris; Simpson, Timothy W; Baik, Seon Pill
2018-05-01
This study presents usability considerations and solutions for the design of glasses-type wearable computer displays and examines their effectiveness in a case study. Design countermeasures were investigated by a four-step design process: (1) preliminary design analysis; (2) design idea generation; (3) final design selection; and (4) virtual fitting trial. Three design interventions were devised from the design process: (1) weight balance to reduce pressure concentrated on the nose, (2) compliant temples to accommodate diverse head sizes and (3) a hanger mechanism to help spectacle users hang their wearable display on their eye glasses. To investigate their effectiveness, in the case study, the novel 3D glasses adopting the three interventions were compared with two existing 3D glasses in terms of neck muscle fatigue and subjective discomfort rating. While neck muscle fatigue was not significantly different among the three glasses (p = 0.467), the novel glasses had significantly smaller discomfort ratings (p = 0.009). Relevance to Industry: A four-step design process identified usability considerations and solutions for the design of glasses-type wearable computer displays. A novel 3D glasses was proposed through the process and its effectiveness was validated. The results identify design considerations and opportunities relevant to the emerging wearable display industry.
Niccolai, Linda M.; Ogden, Lorraine G.; Muehlenbein, Catherine E.; Dziura, James D.; Vázquez, Marietta; Shapiro, Eugene D.
2007-01-01
Objective Case-control studies of the effectiveness of a vaccine are useful to answer important questions, such as the effectiveness of a vaccine over time, that usually are not addressed by pre-licensure clinical trials of the vaccine’s efficacy. This report describes methodological issues related to design and analysis that were used to determine the effects of time since vaccination and age at the time of vaccination. Study Design and Setting A matched case-control study of the effectiveness of varicella vaccine. Results Sampling procedures and conditional logistic regression models including interaction terms are described. Conclusion Use of these methods will allow investigators to assess the effects of a wide range of variables, such as time since vaccination and age at the time of vaccination, on the effectiveness of a vaccine. PMID:17938054
Team effectiveness in academic medical libraries: a multiple case study*
Russo Martin, Elaine
2006-01-01
Objectives: The objective of this study is to apply J. Richard Hackman's framework on team effectiveness to academic medical library settings. Methods: The study uses a qualitative, multiple case study design, employing interviews and focus groups to examine team effectiveness in three academic medical libraries. Another site was selected as a pilot to validate the research design, field procedures, and methods to be used with the cases. In all, three interviews and twelve focus groups, with approximately seventy-five participants, were conducted at the case study libraries. Findings: Hackman identified five conditions leading to team effectiveness and three outcomes dimensions that defined effectiveness. The participants in this study identified additional characteristics of effectiveness that focused on enhanced communication, leadership personality and behavior, and relationship building. The study also revealed an additional outcome dimension related to the evolution of teams. Conclusions: Introducing teams into an organization is not a trivial matter. Hackman's model of effectiveness has implications for designing successful library teams. PMID:16888659
NASA Technical Reports Server (NTRS)
Lovejoy, Andrew E.; Hilburger, Mark W.; Chunchu, Prasad B.
2010-01-01
A design study was conducted to investigate the effect shell buckling knockdown factor (SBKF), internal pressure and aluminum alloy material selection on the structural weight of stiffened cylindrical shells. Two structural optimization codes were used for the design study to determine the optimum minimum-weight design for a series of design cases, and included an in-house developed genetic algorithm (GA) code and PANDA2. Each design case specified a unique set of geometry, material, knockdown factor combinations and loads. The resulting designs were examined and compared to determine the effects of SBKF, internal pressure and material selection on the acreage design weight and controlling failure mode. This design study shows that use of less conservative SBKF values, including internal pressure, and proper selection of material alloy can result in significant weight savings for stiffened cylinders. In particular, buckling-critical cylinders with integrally machined stiffener construction can benefit from the use of thicker plate material that enables taller stiffeners, even when the stiffness, strength and density properties of these materials appear to be inferior.
A Bayesian multi-stage cost-effectiveness design for animal studies in stroke research
Cai, Chunyan; Ning, Jing; Huang, Xuelin
2017-01-01
Much progress has been made in the area of adaptive designs for clinical trials. However, little has been done regarding adaptive designs to identify optimal treatment strategies in animal studies. Motivated by an animal study of a novel strategy for treating strokes, we propose a Bayesian multi-stage cost-effectiveness design to simultaneously identify the optimal dose and determine the therapeutic treatment window for administrating the experimental agent. We consider a non-monotonic pattern for the dose-schedule-efficacy relationship and develop an adaptive shrinkage algorithm to assign more cohorts to admissible strategies. We conduct simulation studies to evaluate the performance of the proposed design by comparing it with two standard designs. These simulation studies show that the proposed design yields a significantly higher probability of selecting the optimal strategy, while it is generally more efficient and practical in terms of resource usage. PMID:27405325
Effects of Cloud-Based m-Learning on Student Creative Performance in Engineering Design
ERIC Educational Resources Information Center
Chang, Yu-Shan; Chen, Si-Yi; Yu, Kuang-Chao; Chu, Yih-Hsien; Chien, Yu-Hung
2017-01-01
This study explored the effects of cloud-based m-learning on students' creative processes and products in engineering design. A nonequivalent pretest-posttest design was adopted, and 62 university students from Taipei City, Taiwan, were recruited as research participants in the study. The results showed that cloud-based m-learning had a positive…
ERIC Educational Resources Information Center
Becuwe, Heleen; Roblin, Natalie Pareja; Tondeur, Jo; Thys, Jeroen; Castelein, Els; Voogt, Joke
2017-01-01
Teacher educators often struggle to model effective integration of technology. Several studies suggest that the involvement of teacher educators in collaborative design is effective in developing the competences necessary for integrating information and communication technology (ICT) in teaching. In a teacher educator design team (TeDT), two or…
ERIC Educational Resources Information Center
Guidera, Stan; MacPherson, D. Scot
2008-01-01
This paper presents the results of a study that was conducted to identify and document student perceptions of the effectiveness of computer modeling software introduced in a design foundations course that had previously utilized only conventional manually-produced representation techniques. Rather than attempt to utilize a production-oriented CAD…
The Effect of Design Teams on Preservice Teachers' Technology Integration
ERIC Educational Resources Information Center
Johnson, Laurene D.
2012-01-01
This study examined the effect of a specific instructional approach called design teams on preservice teachers' attitudes toward technology, their technology skills, and their Technological Pedagogical Content Knowledge (TPACK). In a design teams approach, participants work in collaborative teams to design solutions to solve real-world…
[Effect strength variation in the single group pre-post study design: a critical review].
Maier-Riehle, B; Zwingmann, C
2000-08-01
In Germany, studies in rehabilitation research--in particular evaluation studies and examinations of quality of outcome--have so far mostly been executed according to the uncontrolled one-group pre-post design. Assessment of outcome is usually made by comparing the pre- and post-treatment means of the outcome variables. The pre-post differences are checked, and in case of significance, the results are increasingly presented in form of effect sizes. For this reason, this contribution presents different effect size indices used for the one-group pre-post design--in spite of fundamental doubts which exist in relation to that design due to its limited internal validity. The numerator concerning all effect size indices of the one-group pre-post design is defined as difference between the pre- and post-treatment means, whereas there are different possibilities and recommendations with regard to the denominator and hence the standard deviation that serves as the basis for standardizing the difference of the means. Used above all are standardization oriented towards the standard deviation of the pre-treatment scores, standardization oriented towards the pooled standard deviation of the pre- and post-treatment scores, and standardization oriented towards the standard deviation of the pre-post differences. Two examples are given to demonstrate that the different modes of calculating effect size indices in the one-group pre-post design may lead to very different outcome patterns. Additionally, it is pointed out that effect sizes from the uncontrolled one-group pre-post design generally tend to be higher than effect sizes from studies conducted with control groups. Finally, the pros and cons of the different effect size indices are discussed and recommendations are given.
Qin, Li-Xuan; Levine, Douglas A
2016-06-10
Accurate discovery of molecular biomarkers that are prognostic of a clinical outcome is an important yet challenging task, partly due to the combination of the typically weak genomic signal for a clinical outcome and the frequently strong noise due to microarray handling effects. Effective strategies to resolve this challenge are in dire need. We set out to assess the use of careful study design and data normalization for the discovery of prognostic molecular biomarkers. Taking progression free survival in advanced serous ovarian cancer as an example, we conducted empirical analysis on two sets of microRNA arrays for the same set of tumor samples: arrays in one set were collected using careful study design (that is, uniform handling and randomized array-to-sample assignment) and arrays in the other set were not. We found that (1) handling effects can confound the clinical outcome under study as a result of chance even with randomization, (2) the level of confounding handling effects can be reduced by data normalization, and (3) good study design cannot be replaced by post-hoc normalization. In addition, we provided a practical approach to define positive and negative control markers for detecting handling effects and assessing the performance of a normalization method. Our work showcased the difficulty of finding prognostic biomarkers for a clinical outcome of weak genomic signals, illustrated the benefits of careful study design and data normalization, and provided a practical approach to identify handling effects and select a beneficial normalization method. Our work calls for careful study design and data analysis for the discovery of robust and translatable molecular biomarkers.
Magic Mirror, On the Wall-Which Is the Right Study Design of Them All?-Part II.
Vetter, Thomas R
2017-07-01
The assessment of a new or existing treatment or other intervention typically answers 1 of 3 central research-related questions: (1) "Can it work?" (efficacy); (2) "Does it work?" (effectiveness); or (3) "Is it worth it?" (efficiency or cost-effectiveness). There are a number of study designs that, on a situational basis, are appropriate to apply in conducting research. These study designs are generally classified as experimental, quasiexperimental, or observational, with observational studies being further divided into descriptive and analytic categories. This second of a 2-part statistical tutorial reviews these 3 salient research questions and describes a subset of the most common types of observational study designs. Attention is focused on the strengths and weaknesses of each study design to assist in choosing which is appropriate for a given study objective and hypothesis as well as the particular study setting and available resources and data. Specific studies and papers are highlighted as examples of a well-chosen, clearly stated, and properly executed study design type.
Magic Mirror, on the Wall-Which Is the Right Study Design of Them All?-Part I.
Vetter, Thomas R
2017-06-01
The assessment of a new or existing treatment or intervention typically answers 1 of 3 research-related questions: (1) "Can it work?" (efficacy); (2) "Does it work?" (effectiveness); and (3) "Is it worth it?" (efficiency or cost-effectiveness). There are a number of study designs that on a situational basis are appropriate to apply in conducting research. These study designs are classified as experimental, quasi-experimental, or observational, with observational studies being further divided into descriptive and analytic categories. This first of a 2-part statistical tutorial reviews these 3 salient research questions and describes a subset of the most common types of experimental and quasi-experimental study design. Attention is focused on the strengths and weaknesses of each study design to assist in choosing which is appropriate for a given study objective and hypothesis as well as the particular study setting and available resources and data. Specific studies and papers are highlighted as examples of a well-chosen, clearly stated, and properly executed study design type.
Inlet design for high-speed propfans
NASA Technical Reports Server (NTRS)
Little, B. H., Jr.; Hinson, B. L.
1982-01-01
A two-part study was performed to design inlets for high-speed propfan installation. The first part was a parametric study to select promising inlet concepts. A wide range of inlet geometries was examined and evaluated - primarily on the basis of cruise thrust and fuel burn performance. Two inlet concepts were than chosen for more detailed design studies - one apropriate to offset engine/gearbox arrangements and the other to in-line arrangements. In the second part of this study, inlet design points were chosen to optimize the net installed thrust, and detailed design of the two inlet configurations was performed. An analytical methodology was developed to account for propfan slipstream effects, transonic flow efects, and three-dimensional geometry effects. Using this methodology, low drag cowls were designed for the two inlets.
The Neighbourhood Effects on Health and Well-being (NEHW) study.
O'Campo, Patricia; Wheaton, Blair; Nisenbaum, Rosane; Glazier, Richard H; Dunn, James R; Chambers, Catharine
2015-01-01
Many cross-sectional studies of neighbourhood effects on health do not employ strong study design elements. The Neighbourhood Effects on Health and Well-being (NEHW) study, a random sample of 2412 English-speaking Toronto residents (age 25-64), utilises strong design features for sampling neighbourhoods and individuals, characterising neighbourhoods using a variety of data sources, measuring a wide range of health outcomes, and for analysing cross-level interactions. We describe here methodological issues that shaped the design and analysis features of the NEHW study to ensure that, while a cross-sectional sample, it will advance the quality of evidence emerging from observational studies. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.
Mazzucca, Stephanie; Tabak, Rachel G; Pilar, Meagan; Ramsey, Alex T; Baumann, Ana A; Kryzer, Emily; Lewis, Ericka M; Padek, Margaret; Powell, Byron J; Brownson, Ross C
2018-01-01
The need for optimal study designs in dissemination and implementation (D&I) research is increasingly recognized. Despite the wide range of study designs available for D&I research, we lack understanding of the types of designs and methodologies that are routinely used in the field. This review assesses the designs and methodologies in recently proposed D&I studies and provides resources to guide design decisions. We reviewed 404 study protocols published in the journal Implementation Science from 2/2006 to 9/2017. Eligible studies tested the efficacy or effectiveness of D&I strategies (i.e., not effectiveness of the underlying clinical or public health intervention); had a comparison by group and/or time; and used ≥1 quantitative measure. Several design elements were extracted: design category (e.g., randomized); design type [e.g., cluster randomized controlled trial (RCT)]; data type (e.g., quantitative); D&I theoretical framework; levels of treatment assignment, intervention, and measurement; and country in which the research was conducted. Each protocol was double-coded, and discrepancies were resolved through discussion. Of the 404 protocols reviewed, 212 (52%) studies tested one or more implementation strategy across 208 manuscripts, therefore meeting inclusion criteria. Of the included studies, 77% utilized randomized designs, primarily cluster RCTs. The use of alternative designs (e.g., stepped wedge) increased over time. Fewer studies were quasi-experimental (17%) or observational (6%). Many study design categories (e.g., controlled pre-post, matched pair cluster design) were represented by only one or two studies. Most articles proposed quantitative and qualitative methods (61%), with the remaining 39% proposing only quantitative. Half of protocols (52%) reported using a theoretical framework to guide the study. The four most frequently reported frameworks were Consolidated Framework for Implementing Research and RE-AIM ( n = 16 each), followed by Promoting Action on Research Implementation in Health Services and Theoretical Domains Framework ( n = 12 each). While several novel designs for D&I research have been proposed (e.g., stepped wedge, adaptive designs), the majority of the studies in our sample employed RCT designs. Alternative study designs are increasing in use but may be underutilized for a variety of reasons, including preference of funders or lack of awareness of these designs. Promisingly, the prevalent use of quantitative and qualitative methods together reflects methodological innovation in newer D&I research.
Designing algorithm visualization on mobile platform: The proposed guidelines
NASA Astrophysics Data System (ADS)
Supli, A. A.; Shiratuddin, N.
2017-09-01
This paper entails an ongoing study about the design guidelines of algorithm visualization (AV) on mobile platform, helping students learning data structures and algorithm (DSA) subject effectively. Our previous review indicated that design guidelines of AV on mobile platform are still few. Mostly, previous guidelines of AV are developed for AV on desktop and website platform. In fact, mobile learning has been proved to enhance engagement in learning circumstances, and thus effect student's performance. In addition, the researchers highly recommend including UI design and Interactivity in designing effective AV system. However, the discussions of these two aspects in previous AV design guidelines are not comprehensive. The UI design in this paper describes the arrangement of AV features in mobile environment, whereas interactivity is about the active learning strategy features based on learning experiences (how to engage learners). Thus, this study main objective is to propose design guidelines of AV on mobile platform (AVOMP) that entails comprehensively UI design and interactivity aspects. These guidelines are developed through content analysis and comparative analysis from various related studies. These guidelines are useful for AV designers to help them constructing AVOMP for various topics on DSA.
Effects of Game Design Patterns on Basic Life Support Training Content
ERIC Educational Resources Information Center
Kelle, Sebastian; Klemke, Roland; Specht, Marcus
2013-01-01
Based on a previous analysis of game design patterns and related effects in an educational scenario, the following paper presents an experimental study. In the study a course for Basic Life Support training has been evaluated and two game design patterns have been applied to the course. The hypotheses evaluated in this paper relate to game design…
An SEM Approach for the Evaluation of Intervention Effects Using Pre-Post-Post Designs
ERIC Educational Resources Information Center
Mun, Eun Young; von Eye, Alexander; White, Helene R.
2009-01-01
This study analyzes latent change scores using latent curve models (LCMs) for evaluation research with pre-post-post designs. The article extends a recent article by Willoughby, Vandergrift, Blair, and Granger (2007) on the use of LCMs for studies with pre-post-post designs, and demonstrates that intervention effects can be better tested using…
Sylvia, Louisa G.; Reilly-Harrington, Noreen A.; Leon, Andrew C.; Kansky, Christine I.; Ketter, Terence A.; Calabrese, Joseph R.; Thase, Michael E.; Bowden, Charles L.; Friedman, Edward S.; Ostacher, Michael J.; Iosifescu, Dan V.; Severe, Joanne; Nierenberg, Andrew A.
2013-01-01
Background High attrition rates which occur frequently in longitudinal clinical trials of interventions for bipolar disorder limit the interpretation of results. Purpose The aim of this article is to present design approaches that limited attrition in the Lithium Use for Bipolar Disorder (LiTMUS) Study. Methods LiTMUS was a 6-month randomized, longitudinal multi-site comparative effectiveness trial that examined bipolar participants who were at least mildly ill. Participants were randomized to either low to moderate doses of lithium or no lithium, in addition to other treatments needed for mood stabilization administered in a guideline-informed, empirically supported, and personalized fashion (N=283). Results Components of the study design that may have contributed to the low attrition rate of the study included use of: (1) an intent-to-treat design; (2) a randomized adjunctive single-blind design; (3) participant reimbursement; (4) intent-to-attend the next study visit (includes a discussion of attendance obstacles when intention is low); (5) quality care with limited participant burden; and (6) target windows for study visits. Limitations Site differences and the effectiveness and tolerability data have not been analyzed yet. Conclusions These components of the LiTMUS study design may have reduced the probability of attrition which would inform the design of future randomized clinical effectiveness trials. PMID:22076437
Evaluating the Effects of Culvert Designs on Ecosystem Processes in Northern Wisconsin Streams
J. C. Olson; A. M. Marcarelli; A.L. Timm; S.L. Eggert; R.K. Kolka
2017-01-01
Culvert replacements are commonly undertaken to restore aquatic organism passage and stream hydrologic and geomorphic conditions, but their effects on ecosystem processes are rarely quantified. The objective of this study was to investigate the effects of two culvert replacement designs on stream ecosystem processes. The stream simulation design, where culverts...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-01-25
... these decisionmaking processes will be applied by FDA to help design effective communication strategies..., beliefs, and behaviors--and use risk communications; (2) more efficiently and effectively design messages... provided about the design and methodology of the pretests and the studies to effectively comment on the...
Sediment Export from Forest Road Turn-outs: A Study Design and Preliminary Results
Johnny M. Grace
1998-01-01
This paper reports the design and preliminary results of a study that evaluates the effects of commonly prescribed forest road runoff control treatments. A study design which utilizes runoff samplers, runoff diversion walls, sediment filter bags, and erosion stakes to evaluate sediment transport through runoff control treatments is documented. The study design will...
Relation between experimental and non-experimental study designs. HB vaccines: a case study.
Jefferson, T; Demicheli, V
1999-01-01
To examine the relation between experimental and non-experimental study design in vaccinology. Assessment of each study design's capability of testing four aspects of vaccine performance, namely immunogenicity (the capacity to stimulate the immune system), duration of immunity conferred, incidence and seriousness of side effects, and number of infections prevented by vaccination. Experimental and non-experimental studies on hepatitis B (HB) vaccines in the Cochrane Vaccines Field Database. Experimental and non-experimental vaccine study designs are frequently complementary but some aspects of vaccine quality can only be assessed by one of the types of study. More work needs to be done on the relation between study quality and its significance in terms of effect size.
2006-09-01
Effect sizes are also shown for each randomization group (i.e., effect size from pretest to posttest ) and for the comparison of the two randomization...questions were answered. This study was designed to be a pilot study to quantify effect sizes of the effect of walking on quality of life...physical activity, body composition, and depending on inclusion criteria, estrogen metabolism. Second, this study was designed to assess the degree to
Study on Product Innovative Design Process Driven by Ideal Solution
NASA Astrophysics Data System (ADS)
Zhang, Fuying; Lu, Ximei; Wang, Ping; Liu, Hui
Product innovative design in companies today relies heavily on individual members’ experience and creative ideation as well as their skills of integrating creativity and innovation tools with design methods agilely. Creative ideation and inventive ideas generation are two crucial stages in product innovative design process. Ideal solution is the desire final ideas for given problem, and the striving reaching target for product design. In this paper, a product innovative design process driven by ideal solution is proposed. This design process encourages designers to overcome their psychological inertia, to foster creativity in a systematic way for acquiring breakthrough creative and innovative solutions in a reducing sphere of solution-seeking, and results in effective product innovative design rapidly. A case study example is also presented to illustrate the effectiveness of the proposed design process.
ERIC Educational Resources Information Center
Chen, Mo; Hyppa-Martin, Jolene K.; Reichle, Joe E.; Symons, Frank J.
2016-01-01
Meaningfully synthesizing single case experimental data from intervention studies comprised of individuals with low incidence conditions and generating effect size estimates remains challenging. Seven effect size metrics were compared for single case design (SCD) data focused on teaching speech generating device use to individuals with…
Basic principles of test-negative design in evaluating influenza vaccine effectiveness.
Fukushima, Wakaba; Hirota, Yoshio
2017-08-24
Based on the unique characteristics of influenza, the concept of "monitoring" influenza vaccine effectiveness (VE) across the seasons using the same observational study design has been developed. In recent years, there has been a growing number of influenza VE reports using the test-negative design, which can minimize both misclassification of diseases and confounding by health care-seeking behavior. Although the test-negative designs offer considerable advantages, there are some concerns that widespread use of the test-negative design without knowledge of the basic principles of epidemiology could produce invalid findings. In this article, we briefly review the basic concepts of the test-negative design with respect to classic study design such as cohort studies or case-control studies. We also mention selection bias, which may be of concern in some countries where rapid diagnostic testing is frequently used in routine clinical practices, as in Japan. Copyright © 2017. Published by Elsevier Ltd.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-12-09
... comparative visuals, and using vaguer language. This study is designed to apply the existing comparative... Effectiveness) studies designed to explore comparative effectiveness. When this large project is completed, FDA... Request; Experimental Study of Comparative Direct-to-Consumer Advertising AGENCY: Food and Drug...
Barlow, D H; Hayes, S C
1979-01-01
A little used and often confused design, capable of comparing two treatments within a single subject, has been termed, variously, a multielement baseline design, a multiple schedule design, and a randomization design. The background of these terms is reviewed, and a new, more descriptive term, Alternating Treatments Design, is proposed. Critical differences between this design and a Simultaneous Treatment Design are outlined, and experimental questions answerable by each design are noted. Potential problems with multiple treatment interference in this procedure are divided into sequential confounding, carryover effects, and alternation effects and the importance of these issues vis-a-vis other single-case experimental designs is considered. Methods of minimizing multiple treatment interference as well as methods of studying these effects are outlined. Finally, appropriate uses of Alternating Treatments Designs are described and discussed in the context of recent examples. PMID:489478
In-situ implant containing PCL-curcumin nanoparticles developed using design of experiments.
Kasinathan, Narayanan; Amirthalingam, Muthukumar; Reddy, Neetinkumar D; Jagani, Hitesh V; Volety, Subrahmanyam M; Rao, Josyula Venkata
2016-01-01
Polymeric delivery system is useful in reducing pharmacokinetic limitations viz., poor absorption and rapid elimination associated with clinical use of curcumin. Design of experiment is a precise and cost effective tool useful in analyzing the effect of independent variables and their interaction on the product attributes. To evaluate the effect of process variables involved in preparation of curcumin-loaded polycaprolactone (PCL) nanoparticles (CPN). In the present experiment, CPNs were prepared by emulsification solvent evaporation technique. The effect of independent variables on the dependent variable was analyzed using design of experiments. Anticancer activity of CPN was studied using Ehrlich ascites carcinoma (EAC) model. In-situ implant was developed using PLGA as polymer. The effect of independent variables was studied in two stages. First, the effect of drug-polymer ratio, homogenization speed and surfactant concentration on size was studied using factorial design. The interaction of homogenization speed with homogenization time on mean particle size of CPN was then evaluated using central composite design. In the second stage, the effect of these variables (under the conditions optimized for producing particles <500 nm) on percentage drug encapsulation was evaluated using factorial design. CPN prepared under optimized conditions were able to control the development of EAC in Swiss albino mice and enhanced their survival time. PLGA based in-situ implant containing CPN prepared under optimized conditions showed sustained drug release. This implant could be further evaluated for pharmacological activities.
Jackson, Michael L; Rothman, Kenneth J
2015-03-10
The recently developed test-negative design is now standard for observational studies of influenza vaccine effectiveness (VE). It is unclear how influenza test misclassification biases test-negative VE estimates relative to VE estimates from traditional cohort or case-control studies. We simulated populations whose members may develop acute respiratory illness (ARI) due to influenza and to non-influenza pathogens. In these simulations, vaccination reduces the risk of influenza but not of non-influenza ARI. Influenza test sensitivity and specificity, risks of influenza and non-influenza ARI, and VE were varied across the simulations. In each simulation, we estimated influenza VE using a cohort design, a case-control design, and a test-negative design. In the absence of influenza test misclassification, all three designs accurately estimated influenza VE. In the presence of misclassification, all three designs underestimated VE. Bias in VE estimates was slightly greater in the test-negative design than in cohort or case-control designs. Assuming the use of highly sensitive and specific reverse-transcriptase polymerase chain reaction tests for influenza, bias in the test-negative studies was trivial across a wide range of realistic values for VE. Although influenza test misclassification causes more bias in test-negative studies than in traditional cohort or case-control studies, the difference is trivial for realistic combinations of attack rates, test sensitivity/specificity, and VE. Copyright © 2015 Elsevier Ltd. All rights reserved.
Serious games and blended learning; effects on performance and motivation in medical education.
Dankbaar, Mary
2017-02-01
More efficient, flexible training models are needed in medical education. Information technology offers the tools to design and develop effective and more efficient training. The aims of this thesis were: 1) Compare the effectiveness of blended versus classroom training for the acquisition of knowledge; 2) Investigate the effectiveness and critical design features of serious games for performance improvement and motivation. Five empirical studies were conducted to answer the research questions and a descriptive study on an evaluation framework to assess serious games was performed. The results of the research studies indicated that: 1) For knowledge acquisition, blended learning is equally effective and attractive for learners as classroom learning; 2) A serious game with realistic, interactive cases improved complex cognitive skills for residents, with limited self-study time. Although the same game was motivating for inexperienced medical students and stimulated them to study longer, it did not improve their cognitive skills, compared with what they learned from an instructional e‑module. This indicates an 'expertise reversal effect', where a rich learning environment is effective for experts, but may be contra-productive for novices (interaction of prior knowledge and complexity of format). A blended design is equally effective and attractive as classroom training. Blended learning facilitates adaptation to the learners' knowledge level, flexibility in time and scalability of learning. Games may support skills learning, provided task complexity matches the learner's competency level. More design-based research is needed on the effects of task complexity and other design features on performance improvement, for both novices and experts.
Experimental design methods for bioengineering applications.
Keskin Gündoğdu, Tuğba; Deniz, İrem; Çalışkan, Gülizar; Şahin, Erdem Sefa; Azbar, Nuri
2016-01-01
Experimental design is a form of process analysis in which certain factors are selected to obtain the desired responses of interest. It may also be used for the determination of the effects of various independent factors on a dependent factor. The bioengineering discipline includes many different areas of scientific interest, and each study area is affected and governed by many different factors. Briefly analyzing the important factors and selecting an experimental design for optimization are very effective tools for the design of any bioprocess under question. This review summarizes experimental design methods that can be used to investigate various factors relating to bioengineering processes. The experimental methods generally used in bioengineering are as follows: full factorial design, fractional factorial design, Plackett-Burman design, Taguchi design, Box-Behnken design and central composite design. These design methods are briefly introduced, and then the application of these design methods to study different bioengineering processes is analyzed.
Parametric Study and Design of Tab Shape for Improving Aerodynamic Performance of Rotor Blade
NASA Astrophysics Data System (ADS)
Han, Jaeseong; Kwon, Oh Joon
2018-04-01
In the present study, the parametric study was performed to analyze the effect of the tab on the aerodynamic performance and characteristics of rotor blades. Also, the tab shape was designed to improve the aerodynamic performance of rotor blades. A computational fluid dynamics solver based on three-dimensional Reynolds averaged Navier-Stokes equation using an unstructured mesh was used for the parametric study and the tab design. For airfoils, the effect of length and angle of a tab was studied on the aerodynamic characteristics of airfoils. In addition, including those parameters, the effect of a span of a tab was studied for rotor blades in hovering flight. The results of the parametric study were analyzed in terms of change of the aerodynamic performance and characteristics to understand the effect of a tab. Considering the analysis, the design of tab shape was conducted to improve the aerodynamic performance of rotor blades. The simply attached tab to trailing edge of the rotor blades increases the thrust of the rotor blades without significant changing of aerodynamic characteristics of the rotor blades in hovering and forward flight.
ERIC Educational Resources Information Center
Njoku, N. C.; Njoku, D. I.
2015-01-01
The study is designed to investigate challenges to effective implementation of Christian Religious Studies among secondary school pupils in Ebonyi state. Two research questions were raised to guide the study. The study adopted a descriptive survey design. Ebonyi state is the area of study and the population comprised all the 232 CRS teachers in…
Sullivan, Sheena G; Tchetgen Tchetgen, Eric J; Cowling, Benjamin J
2016-09-01
Influenza viruses undergo frequent antigenic changes. As a result, the viruses circulating change within and between seasons, and the composition of the influenza vaccine is updated annually. Thus, estimation of the vaccine's effectiveness is not constant across seasons. In order to provide annual estimates of the influenza vaccine's effectiveness, health departments have increasingly adopted the "test-negative design," using enhanced data from routine surveillance systems. In this design, patients presenting to participating general practitioners with influenza-like illness are swabbed for laboratory testing; those testing positive for influenza virus are defined as cases, and those testing negative form the comparison group. Data on patients' vaccination histories and confounder profiles are also collected. Vaccine effectiveness is estimated from the odds ratio comparing the odds of testing positive for influenza among vaccinated patients and unvaccinated patients, adjusting for confounders. The test-negative design is purported to reduce bias associated with confounding by health-care-seeking behavior and misclassification of cases. In this paper, we use directed acyclic graphs to characterize potential biases in studies of influenza vaccine effectiveness using the test-negative design. We show how studies using this design can avoid or minimize bias and where bias may be introduced with particular study design variations. © The Author 2016. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
NASA Technical Reports Server (NTRS)
Axelbaum, R. L.; Chen, R.; Sunderland, P. B.; Urban, D. L.; Liu, S.; Chao, B. H.
2001-01-01
This paper summarizes recent studies of the effects of stoichiometric mixture fraction (structure) and hydrodynamics on soot particle inception and flame extinction in diffusion flames. Microgravity experiments are uniquely suited for these studies because, unlike normal gravity experiments, they allow structural and hydrodynamic effects to be independently studied. As part of this recent flight definition program, microgravity studies have been performed in the 2.2 second drop tower. Normal gravity counterflow studies also have been employed and analytical and numerical models have been developed. A goal of this program is to develop sufficient understanding of the effects of flame structure that flames can be "designed" to specifications - consequently, the program name Flame Design. In other words, if a soot-free, strong, low temperature flame is required, can one produce such a flame by designing its structure? Certainly, as in any design, there will be constraints imposed by the properties of the available "materials." For hydrocarbon combustion, the base materials are fuel and air. Additives could be considered, but for this work only fuel, oxygen and nitrogen are considered. Also, the structure of these flames is "designed" by varying the stoichiometric mixture fraction. Following this line of reasoning, the studies described are aimed at developing the understanding of flame structure that is needed to allow for optimum design.
Holland, Carol; Cooper, Yvonne; Shaw, Rachel; Pattison, Helen; Cooke, Richard
2013-01-01
Objective To evaluate behavioural components and strategies associated with increased uptake and effectiveness of screening for coronary heart disease and diabetes with an implementation science focus. Design Realist review. Data sources PubMed, Web of Knowledge, Cochrane Database of Systematic Reviews, Cochrane Controlled Trials Register and reference chaining. Searches limited to English language studies published since 1990. Eligibility criteria Eligible studies evaluated interventions designed to increase the uptake of cardiovascular disease (CVD) and diabetes screening and examined behavioural and/or strategic designs. Studies were excluded if they evaluated changes in risk factors or cost-effectiveness only. Results In 12 eligible studies, several different intervention designs and evidence-based strategies were evaluated. Salient themes were effects of feedback on behaviour change or benefits of health dialogues over simple feedback. Studies provide mixed evidence about the benefits of these intervention constituents, which are suggested to be situation and design specific, broadly supporting their use, but highlighting concerns about the fidelity of intervention delivery, raising implementation science issues. Three studies examined the effects of informed choice or loss versus gain frame invitations, finding no effect on screening uptake but highlighting opportunistic screening as being more successful for recruiting higher CVD and diabetes risk patients than an invitation letter, with no differences in outcomes once recruited. Two studies examined differences between attenders and non-attenders, finding higher risk factors among non-attenders and higher diagnosed CVD and diabetes among those who later dropped out of longitudinal studies. Conclusions If the risk and prevalence of these diseases are to be reduced, interventions must take into account what we know about effective health behaviour change mechanisms, monitor delivery by trained professionals and examine the possibility of tailoring programmes according to contexts such as risk level to reach those most in need. Further research is needed to determine the best strategies for lifelong approaches to screening. PMID:24202056
ERIC Educational Resources Information Center
Park, Sanghoon; Braud, Allison
2017-01-01
This study examined the effects of different multimedia design modalities on middle-school students' motivation and achievement in history and also sought to determine whether an interaction effect on achievement occurs between students' prior knowledge and the different multimedia design modalities. Two groups of eighth-grade students enrolled in…
A d-statistic for single-case designs that is equivalent to the usual between-groups d-statistic.
Shadish, William R; Hedges, Larry V; Pustejovsky, James E; Boyajian, Jonathan G; Sullivan, Kristynn J; Andrade, Alma; Barrientos, Jeannette L
2014-01-01
We describe a standardised mean difference statistic (d) for single-case designs that is equivalent to the usual d in between-groups experiments. We show how it can be used to summarise treatment effects over cases within a study, to do power analyses in planning new studies and grant proposals, and to meta-analyse effects across studies of the same question. We discuss limitations of this d-statistic, and possible remedies to them. Even so, this d-statistic is better founded statistically than other effect size measures for single-case design, and unlike many general linear model approaches such as multilevel modelling or generalised additive models, it produces a standardised effect size that can be integrated over studies with different outcome measures. SPSS macros for both effect size computation and power analysis are available.
ERIC Educational Resources Information Center
Graves, Rick; Barnett, Mardee; Gamble, Yolanda; Kolak, Mike
A case study was used in an instructional design class to facilitate the transfer of conceptual knowledge to concrete concerns and to aid instructional technology graduate students' understanding of the steps involved in designing, analyzing, and implementing an effective needs analysis. The case study involved real events at fictitious company…
Uyei, Jennifer; Braithwaite, R Scott
2016-01-01
Despite the benefits of the placebo-controlled trial design, it is limited by its inability to quantify total benefits and harms. Such trials, for example, are not designed to detect an intervention's placebo or nocebo effects, which if detected could alter the benefit-to-harm balance and change a decision to adopt or reject an intervention. In this article, we explore scenarios in which alternative experimental trial designs, which differ in the type of control used, influence expected value across a range of pretest assumptions and study sample sizes. We developed a decision model to compare 3 trial designs and their implications for decision making: 2-arm placebo-controlled trial ("placebo-control"), 2-arm intervention v. do nothing trial ("null-control"), and an innovative 3-arm trial design: intervention v. do nothing v. placebo trial ("novel design"). Four scenarios were explored regarding particular attributes of a hypothetical intervention: 1) all benefits and no harm, 2) no biological effect, 3) only biological effects, and 4) surreptitious harm (no biological benefit or nocebo effect). Scenario 1: When sample sizes were very small, the null-control was preferred, but as sample sizes increased, expected value of all 3 designs converged. Scenario 2: The null-control was preferred regardless of sample size when the ratio of placebo to nocebo effect was >1; otherwise, the placebo-control was preferred. Scenario 3: When sample size was very small, the placebo-control was preferred when benefits outweighed harms, but the novel design was preferred when harms outweighed benefits. Scenario 4: The placebo-control was preferred when harms outweighed placebo benefits; otherwise, preference went to the null-control. Scenarios are hypothetical, study designs have not been tested in a real-world setting, blinding is not possible in all designs, and some may argue the novel design poses ethical concerns. We identified scenarios in which alternative experimental study designs would confer greater expected value than the placebo-controlled trial design. The likelihood and prevalence of such situations warrant further study. © The Author(s) 2015.
ERIC Educational Resources Information Center
Ugille, Maaike; Moeyaert, Mariola; Beretvas, S. Natasha; Ferron, John M.; Van den Noortgate, Wim
2014-01-01
A multilevel meta-analysis can combine the results of several single-subject experimental design studies. However, the estimated effects are biased if the effect sizes are standardized and the number of measurement occasions is small. In this study, the authors investigated 4 approaches to correct for this bias. First, the standardized effect…
The Moderating Effect of Instructional Conceptions on the Effect of Powerful Learning Environments
ERIC Educational Resources Information Center
Sarfo, Frederick Kwaku; Elen, Jan
2008-01-01
This study aimed at experimentally investigating the moderating role of instructional conceptions on the effectiveness of powerful learning environments (PLE) designed in line with the four-component instructional design model (4C/ID-model). The study also investigated the influence of learning in a 4C/ID PLE on students' instructional…
NASA Astrophysics Data System (ADS)
Chui, T. F. M.; Liu, X.; Zhan, W.
2015-12-01
Green infrastructures (GI) are becoming more important for urban stormwater control worldwide. However, relatively few studies focus on researching the specific designs of GI at household scale. This study assesses the hydrological performance and cost-effectiveness of different GI designs, namely green roofs, bioretention systems and porous pavements. It aims to generate generic insights by comparing the optimal designs of each GI in 2-year and 50-year storms of Hong Kong, China and Seattle, US. EPA SWMM is first used to simulate the hydrologic performance, in particular, the peak runoff reduction of thousands of GI designs. Then, life cycle costs of the designs are computed and their effectiveness, in terms of peak runoff reduction percentage per thousand dollars, is compared. The peak runoff reduction increases almost linearly with costs for green roofs. However, for bioretention systems and porous pavements, peak runoff reduction only increases significantly with costs in the mid values. For achieving the same peak runoff reduction percentage, the optimal soil depth of green roofs increases with the design storm, while surface area does not change significantly. On the other hand, for bioretention systems and porous pavements, the optimal surface area increases with the design storm, while thickness does not change significantly. In general, the cost effectiveness of porous pavements is highest, followed by bioretention systems and then green roofs. The cost effectiveness is higher for a smaller storm, and is thus higher for 2-year storm than 50-year storm, and is also higher for Seattle when compared to Hong Kong. This study allows us to better understand the hydrological performance and cost-effectiveness of different GI designs. It facilitates the implementation of optimal choice and design of each specific GI for stormwater mitigation.
NASA Technical Reports Server (NTRS)
Henne, P. A.; Dahlin, J. A.; Peavey, C. C.; Gerren, D. S.
1982-01-01
The results of design studies and wind tunnel tests of high aspect ratio supercritical wings suitable for a medium range, narrow body transport aircraft flying near M=0.80 were presented. The basic characteristics of the wing design were derived from system studies of advanced transport aircraft where detailed structural and aerodynamic tradeoffs were used to determine the most optimum design from the standpoint of fuel usage and direct operating cost. These basic characteristics included wing area, aspect ratio, average thickness, and sweep. The detailed wing design was accomplished through application of previous test results and advanced computational transonic flow procedures. In addition to the basic wing/body development, considerable attention was directed to nacelle/plyon location effects, horizontal tail effects, and boundary layer transition effects. Results of these tests showed that the basic cruise performance objectives were met or exceeded.
ERIC Educational Resources Information Center
Yilmaz, Turkan Karakus; Cagiltay, Kursat
2016-01-01
Many virtual worlds have been adopted for implementation within educational settings because they are potentially useful for building effective learning environments. Since the flexibility of virtual worlds challenges to obtain effective and efficient educational outcomes, the design of such platforms need more attention. In the present study, the…
The Near-Road Exposures and Effects of Urban Air Pollutants Study (NEXUS): Study Design and Methods
The Near-road EXposures and effects of urban air pollutants Study (NEXUS) was designed to examine the relationship between near-roadway exposures to air pollutants and respiratory outcomes in a cohort of asthmatic children who live close to major roadways in Detroit, Michigan USA...
User Design: A Case Study on Corporate Change
ERIC Educational Resources Information Center
Pastore, Raymond S.; Carr-Chellman, Alison A.; Lohmann, Neal
2011-01-01
The purpose of this study was to examine the effects of implementing user design strategies within the corporate culture. Using a case study design approach, this article explores the change process within a "Fortune" 100 company in which users were given significant decision-making powers. The main focus is on the unique nature of user design in…
The Causal Effects of Father Absence
McLanahan, Sara; Tach, Laura; Schneider, Daniel
2014-01-01
The literature on father absence is frequently criticized for its use of cross-sectional data and methods that fail to take account of possible omitted variable bias and reverse causality. We review studies that have responded to this critique by employing a variety of innovative research designs to identify the causal effect of father absence, including studies using lagged dependent variable models, growth curve models, individual fixed effects models, sibling fixed effects models, natural experiments, and propensity score matching models. Our assessment is that studies using more rigorous designs continue to find negative effects of father absence on offspring well-being, although the magnitude of these effects is smaller than what is found using traditional cross-sectional designs. The evidence is strongest and most consistent for outcomes such as high school graduation, children’s social-emotional adjustment, and adult mental health. PMID:24489431
21 CFR 514.117 - Adequate and well-controlled studies.
Code of Federal Regulations, 2011 CFR
2011-04-01
... experimental units. When the effect of such variables is accounted for by an appropriate design, and when... and well-controlled study should provide sufficient details of study design, conduct, and analysis to... the new animal drug used in the study. (4) The study uses a design that permits a valid comparison...
21 CFR 514.117 - Adequate and well-controlled studies.
Code of Federal Regulations, 2012 CFR
2012-04-01
... experimental units. When the effect of such variables is accounted for by an appropriate design, and when... and well-controlled study should provide sufficient details of study design, conduct, and analysis to... the new animal drug used in the study. (4) The study uses a design that permits a valid comparison...
21 CFR 514.117 - Adequate and well-controlled studies.
Code of Federal Regulations, 2014 CFR
2014-04-01
... experimental units. When the effect of such variables is accounted for by an appropriate design, and when... and well-controlled study should provide sufficient details of study design, conduct, and analysis to... the new animal drug used in the study. (4) The study uses a design that permits a valid comparison...
21 CFR 514.117 - Adequate and well-controlled studies.
Code of Federal Regulations, 2013 CFR
2013-04-01
... experimental units. When the effect of such variables is accounted for by an appropriate design, and when... and well-controlled study should provide sufficient details of study design, conduct, and analysis to... the new animal drug used in the study. (4) The study uses a design that permits a valid comparison...
21 CFR 514.117 - Adequate and well-controlled studies.
Code of Federal Regulations, 2010 CFR
2010-04-01
... experimental units. When the effect of such variables is accounted for by an appropriate design, and when... and well-controlled study should provide sufficient details of study design, conduct, and analysis to... the new animal drug used in the study. (4) The study uses a design that permits a valid comparison...
This paper presents an experimental investigation of the effects of impaction substrate designs and material in reducing particle bounce and reentrainment. Particle collection without coating by using combinations of different impaction substrate designs and surface materials was...
Chen, Ronald C; Carpenter, William R; Kim, Mimi; Hendrix, Laura H; Agans, Robert P; Meyer, Anne-Marie; Hoffmeyer, Anna; Reeve, Bryce B; Nielsen, Matthew E; Usinger, Deborah S; Strigo, Tara S; Jackman, Anne M; Anderson, Mary; Godley, Paul A
2015-01-01
The North Carolina Prostate Cancer Comparative Effectiveness & Survivorship Study (NC ProCESS) was designed in collaboration with stakeholders to compare the effectiveness of different treatment options for localized prostate cancer. Using the Rapid Case Ascertainment system of the North Carolina Central Cancer Registry, 1,419 patients (57% of eligible) with newly-diagnosed localized prostate cancer were enrolled from January 2011 to June 2013, on average 5 weeks after diagnosis. All participants were enrolled prior to treatment and this population-based cohort is sociodemographically diverse. Prospective follow-up continues to collect data on treatments received, disease control, survival and patient-reported outcomes. This study highlights several important considerations regarding stakeholder involvement, study design and generalizability regarding comparative effectiveness research in prostate cancer.
Effect Sizes in Cluster-Randomized Designs
ERIC Educational Resources Information Center
Hedges, Larry V.
2007-01-01
Multisite research designs involving cluster randomization are becoming increasingly important in educational and behavioral research. Researchers would like to compute effect size indexes based on the standardized mean difference to compare the results of cluster-randomized studies (and corresponding quasi-experiments) with other studies and to…
Lansberg, Maarten G; Bhat, Ninad S; Yeatts, Sharon D; Palesch, Yuko Y; Broderick, Joseph P; Albers, Gregory W; Lai, Tze L; Lavori, Philip W
2016-12-01
Adaptive trial designs that allow enrichment of the study population through subgroup selection can increase the chance of a positive trial when there is a differential treatment effect among patient subgroups. The goal of this study is to illustrate the potential benefit of adaptive subgroup selection in endovascular stroke studies. We simulated the performance of a trial design with adaptive subgroup selection and compared it with that of a traditional design. Outcome data were based on 90-day modified Rankin Scale scores, observed in IMS III (Interventional Management of Stroke III), among patients with a vessel occlusion on baseline computed tomographic angiography (n=382). Patients were categorized based on 2 methods: (1) according to location of the arterial occlusive lesion and onset-to-randomization time and (2) according to onset-to-randomization time alone. The power to demonstrate a treatment benefit was based on 10 000 trial simulations for each design. The treatment effect was relatively homogeneous across categories when patients were categorized based on arterial occlusive lesion and time. Consequently, the adaptive design had similar power (47%) compared with the fixed trial design (45%). There was a differential treatment effect when patients were categorized based on time alone, resulting in greater power with the adaptive design (82%) than with the fixed design (57%). These simulations, based on real-world patient data, indicate that adaptive subgroup selection has merit in endovascular stroke trials as it substantially increases power when the treatment effect differs among subgroups in a predicted pattern. © 2016 American Heart Association, Inc.
2006-10-01
agents. Page 5 of 42 BODY Research Study Design & Survey Development: Study Design We designed a prospective quantitative study looking at the...to bioterrorism to different groups of healthcare learners as follows: This research study design was developed in collaboration with the...PDA based format, and printed monograph based format. The research will focus on the effectiveness of distance learning and self-study methodologies
Stiffness Characteristics of Composite Rotor Blades With Elastic Couplings
NASA Technical Reports Server (NTRS)
Piatak, David J.; Nixon, Mark W.; Kosmatka, John B.
1997-01-01
Recent studies on rotor aeroelastic response and stability have shown the beneficial effects of incorporating elastic couplings in composite rotor blades. However, none of these studies have clearly identified elastic coupling limits and the effects of elastic couplings on classical beam stiffnesses of representative rotor blades. Knowledge of these limits and effects would greatly enhance future aeroelastic studies involving composite rotor blades. The present study addresses these voids and provides a preliminary design database for investigators who may wish to study the effects of elastic couplings on representative blade designs. The results of the present study should provide a basis for estimating the potential benefits associated with incorporating elastic couplings without the need for first designing a blade cross section and then performing a cross-section analysis to obtain the required beam section properties as is customary in the usual one-dimensional beam-type approach.
Rotavirus vaccine effectiveness in low-income settings: An evaluation of the test-negative design.
Schwartz, Lauren M; Halloran, M Elizabeth; Rowhani-Rahbar, Ali; Neuzil, Kathleen M; Victor, John C
2017-01-03
The test-negative design (TND), an epidemiologic method currently used to measure rotavirus vaccine (RV) effectiveness, compares the vaccination status of rotavirus-positive cases and rotavirus-negative controls meeting a pre-defined case definition for acute gastroenteritis. Despite the use of this study design in low-income settings, the TND has not been evaluated to measure rotavirus vaccine effectiveness. This study builds upon prior methods to evaluate the use of the TND for influenza vaccine using a randomized controlled clinical trial database. Test-negative vaccine effectiveness (VE-TND) estimates were derived from three large randomized placebo-controlled trials (RCTs) of monovalent (RV1) and pentavalent (RV5) rotavirus vaccines in sub-Saharan Africa and Asia. Derived VE-TND estimates were compared to the original RCT vaccine efficacy estimates (VE-RCTs). The core assumption of the TND (i.e., rotavirus vaccine has no effect on rotavirus-negative diarrhea) was also assessed. TND vaccine effectiveness estimates were nearly equivalent to original RCT vaccine efficacy estimates. Neither RV had a substantial effect on rotavirus-negative diarrhea. This study supports the TND as an appropriate epidemiologic study design to measure rotavirus vaccine effectiveness in low-income settings. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.
ERIC Educational Resources Information Center
Okoye, Nnamdi S.
2008-01-01
The study investigated the selective attentional effects of adjunct study questions inserted before or after the presentation of science flow diagrams. The basic design for the study was a post-test only control group design involving a total of 252 students randomly selected from six secondary schools in Ile-Ife, Oshun State Nigeria. These were…
Mindfulness-based interventions with youth: A comprehensive meta-analysis of group-design studies.
Klingbeil, David A; Renshaw, Tyler L; Willenbrink, Jessica B; Copek, Rebecca A; Chan, Kai Tai; Haddock, Aaron; Yassine, Jordan; Clifton, Jesse
2017-08-01
The treatment effects of Mindfulness-Based Interventions (MBIs) with youth were synthesized from 76 studies involving 6121 participants. A total of 885 effect sizes were aggregated using meta-regression with robust variance estimation. Overall, MBIs were associated with small treatment effects in studies using pre-post (g=0.305, SE=0.039) and controlled designs (g=0.322, SE=0.040). Treatment effects were measured after a follow-up period in 24 studies (n=1963). Results demonstrated that treatment effects were larger at follow-up than post-treatment in pre-post (g=0.462, SE=0.118) and controlled designs (g=0.402, SE=0.081). Moderator analyses indicated that intervention setting and intervention dosage were not meaningfully related to outcomes after controlling for study design quality. With that said, the between-study heterogeneity in the intercept-only models was consistently small, thus limiting the amount of variance for the moderators to explain. A series of exploratory analyses were used to investigate the differential effectiveness of MBIs across four therapeutic process domains and seven therapeutic outcome domains. Small, positive results were generally observed across the process and outcome domains. Notably, MBIs were associated with moderate effects on the process variable of mindfulness in controlled studies (n=1108, g=0.510). Limitations and directions for future research and practice are discussed. Copyright © 2017 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.
Ryan, Patrick B.; Schuemie, Martijn
2013-01-01
Background: Clinical studies that use observational databases, such as administrative claims and electronic health records, to evaluate the effects of medical products have become commonplace. These studies begin by selecting a particular study design, such as a case control, cohort, or self-controlled design, and different authors can and do choose different designs for the same clinical question. Furthermore, published papers invariably report the study design but do not discuss the rationale for the specific choice. Studies of the same clinical question with different designs, however, can generate different results, sometimes with strikingly different implications. Even within a specific study design, authors make many different analytic choices and these too can profoundly impact results. In this paper, we systematically study heterogeneity due to the type of study design and due to analytic choices within study design. Methods and findings: We conducted our analysis in 10 observational healthcare databases but mostly present our results in the context of the GE Centricity EMR database, an electronic health record database containing data for 11.2 million lives. We considered the impact of three different study design choices on estimates of associations between bisphosphonates and four particular health outcomes for which there is no evidence of an association. We show that applying alternative study designs can yield discrepant results, in terms of direction and significance of association. We also highlight that while traditional univariate sensitivity analysis may not show substantial variation, systematic assessment of all analytical choices within a study design can yield inconsistent results ranging from statistically significant decreased risk to statistically significant increased risk. Our findings show that clinical studies using observational databases can be sensitive both to study design choices and to specific analytic choices within study design. Conclusion: More attention is needed to consider how design choices may be impacting results and, when possible, investigators should examine a wide array of possible choices to confirm that significant findings are consistently identified. PMID:25083251
Effects of respirator use on worker performance
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cardarelli, R.
1995-03-01
In 1993, EPRI funded Yankee Atomic Electric Company to examine the effects of respirator use on worker efficiency. Phase I of Yankee`s effort was to develop a study design to determine respirator effects. Given success in Phase I, a larger population will be tested to determine if a stasitically significant respirator effect on performance can be measured. This paper summarizes the 1993 EPRI/Yankee Respirator Effects of Pilot Study, and describes the study design for the 1994 EPRI/Yankee Respirator Study to be conducted at the Oyster Creek Nuclear Power Plant. Also described is a summary of respirator effect studies that havemore » been conducted during the last ten (10) years.« less
Using Time-Series Research Designs to Investigate the Effects of Instruction on SLA.
ERIC Educational Resources Information Center
Mellow, J. Dean; And Others
1996-01-01
Argues that the study of second-language acquisition theory can be enhanced through time-series research designs. Within the context of investigating the effects of second-language instruction, four main reasons for using T-S design are identified. (95 references) (Author/CK)
Peinemann, Frank; Tushabe, Doreen Allen; Kleijnen, Jos
2013-01-01
Background A systematic review may evaluate different aspects of a health care intervention. To accommodate the evaluation of various research questions, the inclusion of more than one study design may be necessary. One aim of this study is to find and describe articles on methodological issues concerning the incorporation of multiple types of study designs in systematic reviews on health care interventions. Another aim is to evaluate methods studies that have assessed whether reported effects differ by study types. Methods and Findings We searched PubMed, the Cochrane Database of Systematic Reviews, and the Cochrane Methodology Register on 31 March 2012 and identified 42 articles that reported on the integration of single or multiple study designs in systematic reviews. We summarized the contents of the articles qualitatively and assessed theoretical and empirical evidence. We found that many examples of reviews incorporating multiple types of studies exist and that every study design can serve a specific purpose. The clinical questions of a systematic review determine the types of design that are necessary or sufficient to provide the best possible answers. In a second independent search, we identified 49 studies, 31 systematic reviews and 18 trials that compared the effect sizes between randomized and nonrandomized controlled trials, which were statistically different in 35%, and not different in 53%. Twelve percent of studies reported both, different and non-different effect sizes. Conclusions Different study designs addressing the same question yielded varying results, with differences in about half of all examples. The risk of presenting uncertain results without knowing for sure the direction and magnitude of the effect holds true for both nonrandomized and randomized controlled trials. The integration of multiple study designs in systematic reviews is required if patients should be informed on the many facets of patient relevant issues of health care interventions. PMID:24416098
Brent, David
2016-04-01
In this commentary, the effects of four family-based preventive interventions designed to augment parent and child resilience, originally designed to prevent mental health and substance abuse, on suicide ideation and attempts are reviewed. Three of the preventive interventions showed a beneficial effect either on child suicide ideation or attempts, and one found a beneficial effect on parental suicidal ideation. The duration of effects in two of these studies was well longer than a decade. These studies suggest that interventions to augment family and child resiliency originally designed to prevent mental health and substance abuse disorders can also have beneficial, often long-term, effects on suicidal ideation and behavior. © 2016 The American Association of Suicidology.
An Analysis of a Contingency Program on Designated Drivers at a College Bar
ERIC Educational Resources Information Center
Kazbour, Richard R.; Bailey, Jon S.
2010-01-01
The present study evaluated the effects of prompts and incentives on designated drivers in a bar. We defined the dependent variable as the percentage of customers either functioning as or riding with a designated driver. We used an ABCA design to evaluate the effectiveness of prompts and incentives on the dependent variable. Results indicated that…
ERIC Educational Resources Information Center
Liu, Min; Rutledge, Keith
This paper investigates the effect of engaging students in designing interactive multimedia programs. The design process has been shown to heighten motivation and to develop skills in project management, research, organization and representation, presentation, and reflection. At the same time, previous studies have also revealed that it is…
ERIC Educational Resources Information Center
Liu, Min; Pedersen, Susan
Current educational theory and practice clearly show that project-based instruction has the potential to enhance learning. Preliminary findings on one type of project-based learning in which students take on the role of hypermedia designers support this claim. This study examined the effect of being hypermedia designers on fourth-graders'…
Effective Principles in Designing E-Course in Light of Learning Theories
ERIC Educational Resources Information Center
Afifi, Muhammad K.; Alamri, Saad S.
2014-01-01
The researchers conducted an exploratory study to determine the design quality of some E-courses delivered via the web to a number of colleagues at the university. Results revealed a number of shortcomings in the design of these courses, mostly due to the absence of effective principles in the design of these E-courses, especially principles of…
Effectiveness-implementation Hybrid Designs
Curran, Geoffrey M.; Bauer, Mark; Mittman, Brian; Pyne, Jeffrey M.; Stetler, Cheryl
2013-01-01
Objectives This study proposes methods for blending design components of clinical effectiveness and implementation research. Such blending can provide benefits over pursuing these lines of research independently; for example, more rapid translational gains, more effective implementation strategies, and more useful information for decision makers. This study proposes a “hybrid effectiveness-implementation” typology, describes a rationale for their use, outlines the design decisions that must be faced, and provides several real-world examples. Results An effectiveness-implementation hybrid design is one that takes a dual focus a priori in assessing clinical effectiveness and implementation. We propose 3 hybrid types: (1) testing effects of a clinical intervention on relevant outcomes while observing and gathering information on implementation; (2) dual testing of clinical and implementation interventions/strategies; and (3) testing of an implementation strategy while observing and gathering information on the clinical intervention’s impact on relevant outcomes. Conclusions The hybrid typology proposed herein must be considered a construct still in evolution. Although traditional clinical effectiveness and implementation trials are likely to remain the most common approach to moving a clinical intervention through from efficacy research to public health impact, judicious use of the proposed hybrid designs could speed the translation of research findings into routine practice. PMID:22310560
ERIC Educational Resources Information Center
Blank, Rolf K.
2004-01-01
The purpose of the three-year CCSSO study was to design, implement, and test the effectiveness of the Data on Enacted Curriculum (DEC) model for improving math and science instruction. The model was tested by measuring its effects with a randomly selected sample of ?treatment? schools at the middle grades level as compared to a control group of…
Rotter, Thomas; Kinsman, Leigh; James, Erica; Machotta, Andreas; Steyerberg, Ewout W
2012-06-18
The purpose of this article is to report on the quality of the existing evidence base regarding the effectiveness of clinical pathway (CPW) research in the hospital setting. The analysis is based on a recently published Cochrane review of the effectiveness of CPWs. An integral component of the review process was a rigorous appraisal of the methodological quality of published CPW evaluations. This allowed the identification of strengths and limitations of the evidence base for CPW effectiveness. We followed the validated Cochrane Effective Practice and Organisation of Care Group (EPOC) criteria for randomized and non-randomized clinical pathway evaluations. In addition, we tested the hypotheses that simple pre-post studies tend to overestimate CPW effects reported. Out of the 260 primary studies meeting CPW content criteria, only 27 studies met the EPOC study design criteria, with the majority of CPW studies (more than 70 %) excluded from the review on the basis that they were simple pre-post evaluations, mostly comparing two or more annual patient cohorts. Methodologically poor study designs are often used to evaluate CPWs and this compromises the quality of the existing evidence base. Cochrane EPOC methodological criteria, including the selection of rigorous study designs along with detailed descriptions of CPW development and implementation processes, are recommended for quantitative evaluations to improve the evidence base for the use of CPWs in hospitals.
ERIC Educational Resources Information Center
Eze, Nneka Justina
2015-01-01
This study assessed the effects of cloze instructional approach on senior secondary school students' achievement in Igbo language reading comprehension. The study utilized a quasi experimental research design of the pretest posttest non-equivalent control group design. The study was conducted in Abakaliki education zone of Ebonyi State of Nigeria.…
Effects of Concept Mapping Instruction Approach on Students' Achievement in Basic Science
ERIC Educational Resources Information Center
Ogonnaya, Ukpai Patricia; Okafor, Gabriel; Abonyi, Okechukwu S.; Ugama, J. O.
2016-01-01
The study investigated the effects of concept mapping on students' achievement in basic science. The study was carried out in Ebonyi State of Nigeria. The study employed a quasi-experimental design. Specifically the pretest posttest non-equivalent control group research design was used. The sample was 122 students selected from two secondary…
ERIC Educational Resources Information Center
Al-Balushi, Sulaiman M.; Al-Aamri, Shamsa S.
2014-01-01
The current study explores the effectiveness of involving students in environmental science projects for their environmental knowledge and attitudes towards science. The study design is a quasi-experimental pre-post control group design. The sample was 62 11th-grade female students studying at a public school in Oman. The sample was divided into…
Gilal, Faheem Gul; Zhang, Jian; Gilal, Naeem Gul; Gilal, Rukhsana Gul
2018-01-01
The present study integrates self-determined needs satisfaction into a relationship between product design (eg, aesthetic, functional, and symbolic design) and consumer behavior (eg, willingness-to-pay [WTP] a premium and negative word-of-mouth [WOM]) and to explore whether gender can differentiate the effects of aesthetic, functional, and symbolic product designs on self-determined needs satisfaction. To this end, participants from Pakistan and China were recruited, and the hypotheses for this study were tested using structural equation modeling and SPSS-PROCESS. The effects of three product designs on self-determined needs satisfaction were significantly positive across samples. The results further show that self-determined needs satisfaction had the strongest positive effect on WTP a premium and the strongest negative effect on vindictive WOM for Pakistanis. Self-determined needs frustration had the strongest negative effect on the WTP a premium for Chinese participants and an equivalent magnitude effect on vindictive WOM for Pakistani and Chinese participants. The cross-cultural gender-specific findings revealed that Pakistani men are more aesthetic and hedonic than women in Pakistan. Surprisingly, Chinese women resemble Pakistani men in the sense that they prefer aesthetically pleasing products. Chinese men resemble Pakistani women in terms of little interest in symbolic products, whereas Chinese women and Pakistani men respond similarly regarding their decisions to choose symbolic products. To the best of the authors' knowledge, the present study is one of the initial attempts to integrate self-determined needs into the relationship between product design and consumer WTP a premium and WOM, and further explore cross-cultural gender-specific differences across Pakistan and China. The findings of the present study may help international marketers in terms of segmenting, targeting, and positioning their markets.
Blended Course Design: A Synthesis of Best Practices
ERIC Educational Resources Information Center
McGee, Patricia; Reis, Abby
2012-01-01
Blended or hybrid course offerings in higher education are commonplace and much has been written about how to design a blended course effectively. This study examines publically available guides, documents, and books that espouse best or effective practices in blended course design to determine commonalities among such practices. A qualitative…
ERIC Educational Resources Information Center
Ashfaq, Muhammad; Chaudry, Muhammad Ajmal; Iqbal, Muhammad Javed
2016-01-01
The main objective of this study was to ensure instructional quality, effectiveness, efficiency and enjoyment. Instructional design maximizes the value of the instructions for the learners. Instructional design include identifying instructional out-comes, developing instructional contents and established how instructional effectiveness will be…
THE EFFECT OF VARYING ELECTROFISHING DESIGNS AND DISTANCES ON METRIC SCORES IN LARGE RIVERS
To study the effects of electrofishing design and distance on metric scores, we electrofished almost 180 km across four rivers of the Ohio River basin and collected data on more than 28,000 fish. We compared three electrofishing designs using four fish assemblage composition met...
Effect Size Calculations and Single Subject Designs
ERIC Educational Resources Information Center
Olive, Melissa L.; Smith, Benjamin W.
2005-01-01
This study compared visual analyses with five alternative methods for assessing the magnitude of effect with single subject designs. Each method was successful in detecting intervention effect. When rank ordered, each method was consistent in identifying the participants with the largest effect. We recommend the use of the standard mean difference…
An Improvement in Instructional Quality: Can Evaluation of Teaching Effectiveness Make a Difference?
ERIC Educational Resources Information Center
Ngware, Moses Waithanji; Ndirangu, Mwangi
2005-01-01
Purpose: To report study findings on teaching effectiveness and feedback mechanisms in Kenyan universities, which can guide management in developing a comprehensive quality control policy. Design/methodology/approach: The study adopted an exploratory descriptive design. Three public and two private universities were randomly selected to…
Robinson, John W
2012-03-01
Propensity score models are increasingly used in observational comparative effectiveness studies to reduce confounding by covariates that are associated with both a study outcome and treatment choice. Any such potentially confounding covariate will bias estimation of the effect of treatment on the outcome, unless the distribution of that covariate is well-balanced between treatment and control groups. Constructing a subsample of treated and control subjects who are matched on estimated propensity scores is a means of achieving such balance for covariates that are included in the propensity score model. If, during study design, investigators assemble a comprehensive inventory of known and suspected potentially confounding covariates, examination of how well this inventory is covered by the chosen dataset yields an assessment of the extent of bias reduction that is possible by matching on estimated propensity scores. These considerations are explored by examining the designs of three recently published comparative effectiveness studies.
1981-02-01
3 Design ..................................................................... 3 Independent Variables...Prestwood & Weiss, 1978), which were designed to assess the effects of KR, the provision of "KR wa ; onf.,tidod with paring of item presentation...ach Item. -3- The present study was designed to separately examine the effects of KR and of computer- versus self-pacing of item presentation in order
Federal Register 2010, 2011, 2012, 2013, 2014
2010-06-16
... Advertisements for Prescription Drugs. This study is designed to investigate efficacy and effectiveness... efficacy of potential pharmaceutical options (OMB control no. 0910-0649). Design Overview This study will... conditions. This design will allow us to compare consumers' perceptions of efficacy with a more objective...
Lakens, Daniël
2013-01-01
Effect sizes are the most important outcome of empirical studies. Most articles on effect sizes highlight their importance to communicate the practical significance of results. For scientists themselves, effect sizes are most useful because they facilitate cumulative science. Effect sizes can be used to determine the sample size for follow-up studies, or examining effects across studies. This article aims to provide a practical primer on how to calculate and report effect sizes for t-tests and ANOVA's such that effect sizes can be used in a-priori power analyses and meta-analyses. Whereas many articles about effect sizes focus on between-subjects designs and address within-subjects designs only briefly, I provide a detailed overview of the similarities and differences between within- and between-subjects designs. I suggest that some research questions in experimental psychology examine inherently intra-individual effects, which makes effect sizes that incorporate the correlation between measures the best summary of the results. Finally, a supplementary spreadsheet is provided to make it as easy as possible for researchers to incorporate effect size calculations into their workflow. PMID:24324449
Gaming in the Classroom: An Innovative Way to Teach Factorial Designs
ERIC Educational Resources Information Center
Stansbury, Jessica A.; Munro, Geoffrey D.
2013-01-01
This study tested the effectiveness of video game use for instruction of factorial designs in a research methods course. Students designed and conducted a mini study, playing "Dance, Dance, Revolution", using video game scores as the dependent variable. A mixed-design analysis of variance revealed a significantly greater increase from pretest to…
Emotional Design in Multimedia: Does Gender and Academic Achievement Influence Learning Outcomes?
ERIC Educational Resources Information Center
Kumar, Jeya Amantha; Muniandy, Balakrishnan; Yahaya, Wan Ahmad Jaafar Wan
2016-01-01
This study was designed as a preliminary study (N = 33) to explore the effects of gender and academic achievement (Cumulative Grade Point Average-CGPA) on polytechnic students' learning outcomes when exposed to Multimedia Learning Environments (MLE) designed to induce emotions. Three designs namely positive (PosD), neutral (NeuD) and negative…
Factorial versus multi-arm multi-stage designs for clinical trials with multiple treatments.
Jaki, Thomas; Vasileiou, Despina
2017-02-20
When several treatments are available for evaluation in a clinical trial, different design options are available. We compare multi-arm multi-stage with factorial designs, and in particular, we will consider a 2 × 2 factorial design, where groups of patients will either take treatments A, B, both or neither. We investigate the performance and characteristics of both types of designs under different scenarios and compare them using both theory and simulations. For the factorial designs, we construct appropriate test statistics to test the hypothesis of no treatment effect against the control group with overall control of the type I error. We study the effect of the choice of the allocation ratios on the critical value and sample size requirements for a target power. We also study how the possibility of an interaction between the two treatments A and B affects type I and type II errors when testing for significance of each of the treatment effects. We present both simulation results and a case study on an osteoarthritis clinical trial. We discover that in an optimal factorial design in terms of minimising the associated critical value, the corresponding allocation ratios differ substantially to those of a balanced design. We also find evidence of potentially big losses in power in factorial designs for moderate deviations from the study design assumptions and little gain compared with multi-arm multi-stage designs when the assumptions hold. © 2016 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd. © 2016 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd.
Erin L. Landguth; Bradley C. Fedy; Sara J. Oyler-McCance; Andrew L. Garey; Sarah L. Emel; Matthew Mumma; Helene H. Wagner; Marie-Josee Fortin; Samuel A. Cushman
2012-01-01
The influence of study design on the ability to detect the effects of landscape pattern on gene flow is one of the most pressing methodological gaps in landscape genetic research. To investigate the effect of study design on landscape genetics inference, we used a spatially-explicit, individual-based program to simulate gene flow in a spatially continuous population...
NASA Technical Reports Server (NTRS)
Tomberlin, T. J.
1985-01-01
Research studies of residents' responses to noise consist of interviews with samples of individuals who are drawn from a number of different compact study areas. The statistical techniques developed provide a basis for those sample design decisions. These techniques are suitable for a wide range of sample survey applications. A sample may consist of a random sample of residents selected from a sample of compact study areas, or in a more complex design, of a sample of residents selected from a sample of larger areas (e.g., cities). The techniques may be applied to estimates of the effects on annoyance of noise level, numbers of noise events, the time-of-day of the events, ambient noise levels, or other factors. Methods are provided for determining, in advance, how accurately these effects can be estimated for different sample sizes and study designs. Using a simple cost function, they also provide for optimum allocation of the sample across the stages of the design for estimating these effects. These techniques are developed via a regression model in which the regression coefficients are assumed to be random, with components of variance associated with the various stages of a multi-stage sample design.
Power Peaking Effect of OTTO Fuel Scheme Pebble Bed Reactor
NASA Astrophysics Data System (ADS)
Setiadipura, T.; Suwoto; Zuhair; Bakhri, S.; Sunaryo, G. R.
2018-02-01
Pebble Bed Reactor (PBR) type of Hight Temperature Gas-cooled Reactor (HTGR) is a very interesting nuclear reactor design to fulfill the growing electricity and heat demand with a superior passive safety features. Effort to introduce the PBR design to the market can be strengthen by simplifying its system with the Once-through-then-out (OTTO) cycle PBR in which the pebble fuel only pass the core once. Important challenge in the OTTO fuel scheme is the power peaking effect which limit the maximum nominal power or burnup of the design. Parametric survey is perform in this study to investigate the contribution of different design parameters to power peaking effect of OTTO cycle PBR. PEBBED code is utilized in this study to perform the equilibrium PBR core analysis for different design parameter and fuel scheme. The parameters include its core diameter, height-per-diameter (H/D), power density, and core nominal power. Results of this study show that diameter and H/D effectsare stronger compare to the power density and nominal core power. Results of this study might become an importance guidance for design optimization of OTTO fuel scheme PBR.
Macken, Ailbhe; Le Page, Gareth; Hayfield, Amanda; Williams, Timothy D; Brown, Rebecca J
2012-09-01
Potamopyrgus antipodarum is a candidate for a standardized mollusk partial life-cycle study. This is a comparative study of two test designs (microplate and beaker), with additional endpoints to the proposed guideline methods, for example, tracking of continuous reproductive output over 28 d and attributing it to individual female snails. In addition, an investigation of the effects of temperature (16, 20, and 25°C) on reproduction was also conducted employing the microplate design. Copyright © 2012 SETAC.
Curran, Geoffrey M; Bauer, Mark; Mittman, Brian; Pyne, Jeffrey M; Stetler, Cheryl
2012-03-01
This study proposes methods for blending design components of clinical effectiveness and implementation research. Such blending can provide benefits over pursuing these lines of research independently; for example, more rapid translational gains, more effective implementation strategies, and more useful information for decision makers. This study proposes a "hybrid effectiveness-implementation" typology, describes a rationale for their use, outlines the design decisions that must be faced, and provides several real-world examples. An effectiveness-implementation hybrid design is one that takes a dual focus a priori in assessing clinical effectiveness and implementation. We propose 3 hybrid types: (1) testing effects of a clinical intervention on relevant outcomes while observing and gathering information on implementation; (2) dual testing of clinical and implementation interventions/strategies; and (3) testing of an implementation strategy while observing and gathering information on the clinical intervention's impact on relevant outcomes. The hybrid typology proposed herein must be considered a construct still in evolution. Although traditional clinical effectiveness and implementation trials are likely to remain the most common approach to moving a clinical intervention through from efficacy research to public health impact, judicious use of the proposed hybrid designs could speed the translation of research findings into routine practice.
ERIC Educational Resources Information Center
Tozkoparam, Süleyman Burak; Kiliç, Muhammet Emre; Usta, Ertugrul
2015-01-01
The aim of this study is to determine Technological Pedagogical Content Knowledge (TPACK) Competencies of teacher candidates in Turkish Teaching department of Mevlana (Rumi) University and the effect of Instructional Technology and Material Design (ITMD) Course on TPACK. The study is a study of quantitative type and single-group pretest-posttest…
Effect of Pedagogical Formation Program on Pre-Service History Teachers' Perceived Self-Efficacy
ERIC Educational Resources Information Center
Yazici, Fatih; Yildirim, Tercan
2017-01-01
The purpose of the present study is to investigate pre-service history teachers' perceived self-efficacy and the effect of pedagogical formation training on this perception. The study is based on a one-group pretest-posttest research design, which is a type of pre-experimental design. For the purpose of the study, in the first week of the…
ERIC Educational Resources Information Center
Graham, Lori; Graham, Anna; West, Courtney
2015-01-01
This study was designed to demonstrate the effect of implementing multi-component vocabulary strategy instruction in fourth grade social studies. Curriculum was designed for a six-week period and was intended to actively engage students and reinforce retention of word meanings in isolation and in context. Teachers were randomly chosen for…
USDA-ARS?s Scientific Manuscript database
Results from studies on lactation responses to diet have been hypothesized to be affected by the use of change-over (CHANGE) instead of continuous (CONT) experimental designs; a direct test of this hypothesis has not been well-studied. The objective of this study was to evaluate the effects of reduc...
ERIC Educational Resources Information Center
Al Kuwaiti, Ahmed; AlQuraan, Mahmoud; Subbarayalu, Arun Vijay
2016-01-01
Objective: This study aims to investigate the interaction between response rate and class size and its effects on students' evaluation of instructors and the courses offered at a higher education Institution in Saudi Arabia. Study Design: A retrospective study design was chosen. Methods: One thousand four hundred and forty four different courses…
ERIC Educational Resources Information Center
Mintz, Chelsey A.
2017-01-01
The purpose of this action research study was to examine the effects of implementing an online professional learning community (PLC) designed explicitly for teachers of gifted and talented (GT) English language arts (ELA) courses. The present action research (AR) is a limited mixed design study, including quantitative and qualitative elements, to…
A critical component in the design of the Chemical Effects in Biological Systems (CEBS) Knowledgebase is a strategy to capture toxicogenomics study protocols and the toxicity endpoint data (clinical pathology and histopathology). A Study is generally an experiment carried out du...
Observational studies are complementary to randomized controlled trials.
Grootendorst, Diana C; Jager, Kitty J; Zoccali, Carmine; Dekker, Friedo W
2010-01-01
Randomized controlled trials (RCTs) are considered the gold standard study design to investigate the effect of health interventions, including treatment. However, in some situations, it may be unnecessary, inappropriate, impossible, or inadequate to perform an RCT. In these special situations, well-designed observational studies, including cohort and case-control studies, may provide an alternative to doing nothing in order to obtain estimates of treatment effect. It should be noted that such studies should be performed with caution and correctly. The aims of this review are (1) to explain why RCTs are considered the optimal study design to evaluate treatment effects, (2) to describe the situations in which an RCT is not possible and observational studies are an adequate alternative, and (3) to explain when randomization is not needed and can be approximated in observational studies. Examples from the nephrology literature are used for illustration. Copyright 2009 S. Karger AG, Basel.
Survival and migration behavior of juvenile salmonids at Lower Granite Dam, 2006
Beeman, John W.; Fielding, Scott D.; Braatz, Amy C.; Wilkerson, Tamara S.; Pope, Adam C.; Walker, Christopher E.; Hardiman, Jill M.; Perry, Russell W.; Counihan, Timothy D.
2008-01-01
We described behavior and estimated passage and survival parameters of juvenile salmonids during spring and summer migration periods at Lower Granite Dam in 2006. During the spring, the study was designed to examine the effects of the Behavioral Guidance Structure (BGS) by using a randomized-block BGS Stored / BGS Deployed treatment design. The summer study was designed to compare passage and survival through Lower Granite Dam using a randomized-block design during two spill treatments while the BGS was in the stored position. We used the Route Specific Survival Model to estimate survival and passage probabilities of hatchery yearling Chinook salmon, hatchery juvenile steelhead, and hatchery and wild subyearling Chinook salmon. We also estimated fish guidance efficiency (FGE), fish passage efficiency (FPE), Removable Spillway Weir passage effectiveness (RPE), spill passage effectiveness (SPY), and combined spill and RSW passage effectiveness.
Outcomes of online support and resources for cancer survivors: a systematic literature review.
Hong, Yan; Peña-Purcell, Ninfa C; Ory, Marcia G
2012-03-01
This study aims to review systematically the available literature on health outcomes of online cancer support and resources. We searched major databases with the following selection criteria: (1) empirical study on use of online support or resources by cancer survivors, (2) reporting effects or outcomes of online support or resources, (3) focusing on adult cancer survivors, and (4) peer-reviewed articles published by 2010. A total of 24 studies (37 articles) were included in the review. Most studies were focused on breast cancer survivors and had small sample sizes. Fifteen studies employed a cross-sectional design including eight qualitative studies. Only five studies used pre-post design, and four employed RCT design. The outcome measures have focused on psychosocial effects; most studies reported positive effects, although none of the RCT studies reported significant outcomes. Existing studies of online cancer support and resources have demonstrated preliminary but inconclusive evidence for positive outcomes. We call for additional studies with rigorous study designs and the inclusion of more diverse participants and cancer conditions. Connecting diverse cancer survivors to culturally appropriate, evidence-based online support and resources is a strategy to enhance health outcomes. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.
Lipsitch, Marc; Jha, Ayan; Simonsen, Lone
2016-12-01
Although randomized placebo-controlled trials (RCT) are critical to establish efficacy of vaccines at the time of licensure, important remaining questions about vaccine effectiveness (VE)-used here to include individual-level measures and population-wide impact of vaccine programmes-can only be answered once the vaccine is in use, from observational studies. However, such studies are inherently at risk for bias. Using a causal framework and illustrating with examples, we review newer approaches to detecting and avoiding confounding and selection bias in three major classes of observational study design: cohort, case-control and ecological studies. Studies of influenza VE, especially in seniors, are an excellent demonstration of the challenges of detecting and reducing such bias, and so we use influenza VE as a running example. We take a fresh look at the time-trend studies often dismissed as 'ecological'. Such designs are the only observational study design that can measure the overall effect of a vaccination programme [indirect (herd) as well as direct effects], and are in fact already an important part of the evidence base for several vaccines currently in use. Despite the great strides towards more robust observational study designs, challenges lie ahead for evaluating best practices for achieving robust unbiased results from observational studies. This is critical for evaluation of national and global vaccine programme effectiveness. © The Author 2016; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.
NASA Technical Reports Server (NTRS)
1972-01-01
An analysis and design effort was conducted as part of the study of solid rocket motor for a space shuttle booster. The 156-inch-diameter, parallel burn solid rocket motor was selected as its baseline because it is transportable and is the most cost-effective, reliable system that has been developed and demonstrated. The basic approach was to concentrate on the selected baseline design, and to draw from the baseline sufficient data to describe the alternate approaches also studied. The following conclusions were reached with respect to technical feasibility of the use of solid rocket booster motors for the space shuttle vehicle: (1) The 156-inch, parallel-burn baseline SRM design meets NASA's study requirements while incorporating conservative safety factors. (2) The solid rocket motor booster represents a cost-effective approach. (3) Baseline costs are conservative and are based on a demonstrated design. (4) Recovery and reuse are feasible and offer substantial cost savings. (5) Abort can be accomplished successfully. (6) Ecological effects are acceptable.
Backhouse, Martin E
2002-01-01
A number of approaches to conducting economic evaluations could be adopted. However, some decision makers have a preference for wholly stochastic cost-effectiveness analyses, particularly if the sampled data are derived from randomised controlled trials (RCTs). Formal requirements for cost-effectiveness evidence have heightened concerns in the pharmaceutical industry that development costs and times might be increased if formal requirements increase the number, duration or costs of RCTs. Whether this proves to be the case or not will depend upon the timing, nature and extent of the cost-effectiveness evidence required. To illustrate how different requirements for wholly stochastic cost-effectiveness evidence could have a significant impact on two of the major determinants of new drug development costs and times, namely RCT sample size and study duration. Using data collected prospectively in a clinical evaluation, sample sizes were calculated for a number of hypothetical cost-effectiveness study design scenarios. The results were compared with a baseline clinical trial design. The sample sizes required for the cost-effectiveness study scenarios were mostly larger than those for the baseline clinical trial design. Circumstances can be such that a wholly stochastic cost-effectiveness analysis might not be a practical proposition even though its clinical counterpart is. In such situations, alternative research methodologies would be required. For wholly stochastic cost-effectiveness analyses, the importance of prior specification of the different components of study design is emphasised. However, it is doubtful whether all the information necessary for doing this will typically be available when product registration trials are being designed. Formal requirements for wholly stochastic cost-effectiveness evidence based on the standard frequentist paradigm have the potential to increase the size, duration and number of RCTs significantly and hence the costs and timelines associated with new product development. Moreover, it is possible to envisage situations where such an approach would be impossible to adopt. Clearly, further research is required into the issue of how to appraise the economic consequences of alternative economic evaluation research strategies.
Precision of Curriculum-Based Measurement Reading Data: Considerations for Multiple-Baseline Designs
ERIC Educational Resources Information Center
Klingbeil, David A.; Van Norman, Ethan R.; Nelson, Peter M.
2017-01-01
Single-case designs provide an established technology for evaluating the effects of academic interventions. Researchers interested in studying the long-term effects of reading interventions often use curriculum-based measures of reading (CBM-R) as they possess many of the desirable characteristics for use in a time-series design. The reliability…
Assessing the Effectiveness of a Computer Simulation for Teaching Ecological Experimental Design
ERIC Educational Resources Information Center
Stafford, Richard; Goodenough, Anne E.; Davies, Mark S.
2010-01-01
Designing manipulative ecological experiments is a complex and time-consuming process that is problematic to teach in traditional undergraduate classes. This study investigates the effectiveness of using a computer simulation--the Virtual Rocky Shore (VRS)--to facilitate rapid, student-centred learning of experimental design. We gave a series of…
Group Projects in Interior Design Studio Classes: Peer Feedback Benefits
ERIC Educational Resources Information Center
Jurado, Juan A.
2011-01-01
Group projects have been shown to be effective for providing peer feedback in classrooms. While students in regular enrollment classes benefit from peer feedback, low-enrollment classes face many challenges. This study compares peer feedback effectiveness between two interior design studio classes with different design projects. In one class,…
Do Particular Design Features Assist People with Aphasia to Comprehend Text? An Exploratory Study
ERIC Educational Resources Information Center
Wilson, Lucy; Read, Jennifer
2016-01-01
Background: Much of the evidence underlying guidelines for producing accessible information for people with aphasia focuses on client preference for particular design features. There is limited evidence regarding the effects of these features on comprehension. Aims: To examine the effects of specific design features on text comprehension. It was…
Metrik, Jane; Rohsenow, Damaris J.; Monti, Peter M.; McGeary, John; Cook, Travis A. R.; de Wit, Harriet; Haney, Margaret; Kahler, Christopher W.
2009-01-01
Although alcohol and nicotine administration studies have demonstrated that manipulating subjects’ expectancies regarding drug content affects drug response, research with marijuana has not adequately studied drug expectancy effects. The present pilot study was the first to evaluate the credibility and effect of expectancy manipulation on subjective measures and smoking patterns using a marijuana administration balanced-placebo design (BPD). In a 2 × 2 instructional set (told delta-9-tetrahydrocannabinol [THC] vs. told no THC) by drug (smoked marijuana with 2.8% THC vs. placebo) between-subjects design, the authors examined the effect of marijuana expectancy manipulation and the pharmacologic effect on affective and physiologic measures, cigarette ratings, and smoking behavior with 20 marijuana smokers (mean age = 20 years; 25% female). Large main effects of expectancy were found on ratings of cigarette potency, strength, taste, smell, and satisfaction, and observed smoking behavior. Pharmacologic effects were particularly evident for self-reported physical reactions to marijuana and cigarette potency and satisfaction ratings. This study demonstrated the feasibility of the BPD research with marijuana and yielded promising results for future studies examining the independent and combined effects of marijuana pharmacology and expectancies. PMID:19653787
Fedewa, Alicia L; Ahn, Soyeon; Reese, Robert J; Suarez, Marietta M; Macquoid, Ahjane; Davis, Matthew C; Prout, H Thompson
2016-06-01
The present study is a quantitative synthesis of the available literature to investigate the efficacy of psychotherapy for children's mental health outcomes. In particular, this study focuses on potential moderating variables-study design, treatment, client, and therapist characteristics-that may influence therapeutic outcomes for youth but have not been thoroughly accounted for in prior meta-analytic studies. An electronic search of relevant databases resulted in 190 unpublished and published studies that met criteria for inclusion in the analysis. Effect sizes differed by study design. Pre-post-test designs resulted in absolute magnitudes of treatment effects ranging from |-0.02| to |-0.76| while treatment versus control group comparison designs resulted in absolute magnitudes of treatment effects ranging from |-0.14| to |-2.39|. Changes in youth outcomes larger than 20% were found, irrespective of study design, for outcomes focused on psychosomatization (29% reduction), school attendance (25% increase), and stress (48% reduction). The magnitude of changes after psychotherapy ranged from 6% (externalizing problems) to 48% (stress). Several moderator variables significantly influenced psychotherapy treatment effect sizes, including frequency and length of treatment as well as treatment format. However, results did not support the superiority of a single type of intervention for most outcomes. Implications for therapy with school-aged youth and future research are discussed. Copyright © 2016 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.
Carotid Intima-Media Thickness Studies: Study Design and Data Analysis
Bots, Michiel L.
2013-01-01
Background Carotid intima-media thickness (CIMT) measurements have been widely used as primary endpoint in studies into the effects of new interventions as alternative for cardiovascular morbidity and mortality. There are no accepted standards on the use of CIMT measurements in intervention studies and choices in the design and analysis of a CIMT study are generally based on experience and expert opinion. In the present review, we provide an overview of the current evidence on several aspects in the design and analysis of a CIMT study on the early effects of new interventions. Summary of Issues A balanced evaluation of the carotid segments, carotid walls, and image view to be used as CIMT study endpoint; the reading method (manual or semi-automated and continuously or in batch) to be employed, the required sample size, and the frequency of ultrasound examinations is provided. We also discuss the preferred methods to analyse longitudinal CIMT data and address the possible impact of, and methods to deal with missing and biologically implausible CIMT values. Conclusions Linear mixed effects models are the preferred way to analyse CIMT data and do appropriately handle missing and biologically implausible CIMT values. Furthermore, we recommend to use extensive CIMT designs that measure CIMT at regular points during the multiple carotid sites as such approach is likely to increase the success rates of CIMT intervention studies designed to evaluate the effects of new interventions on atherosclerotic burden. PMID:24324938
NASA Technical Reports Server (NTRS)
Thomas, R. E.; Gaines, G. B.
1978-01-01
Recommended design procedures to reduce the complete factorial design by retaining information on anticipated important interaction effects, and by generally giving up information on unconditional main effects are discussed. A hypothetical photovoltaic module used in the test design is presented. Judgments were made of the relative importance of various environmental stresses such as UV radiation, abrasion, chemical attack, temperature, mechanical stress, relative humidity and voltage. Consideration is given to a complete factorial design and its graphical representation, elimination of selected test conditions, examination and improvement of an engineering design, and parametric study. The resulting design consists of a mix of conditional main effects and conditional interactions and represents a compromise between engineering and statistical requirements.
The Design of Effective Case Study-Related Learning Strategies Training.
ERIC Educational Resources Information Center
Nuttall, Alice E.
The development of case study training materials for an experimental research strategy is described, and the effects of such training are discussed. The theoretical foundation for learning strategies training was a social-cognitive/expectancy value model of college learning and teaching. In a posttest-only 2-group design, 54 students in an…
The Effects of STI Education on Korean Adolescents Using Smartphone Applications
ERIC Educational Resources Information Center
Jeong, Sookyung; Cha, Chiyoung; Lee, Jacob
2017-01-01
Objective: This study aimed to compare the effectiveness of adolescents' use of smartphone applications and educational booklets in an educational programme about sexually transmitted infections (STIs). Design: Non-equivalent control-group time-series design. Setting: The study was conducted in two public high schools located in two urban areas of…
ERIC Educational Resources Information Center
Tse, Tony; Vegh, Sandor; Shneiderman, Ben; Marchionini, Gary
1999-01-01
The purpose of this exploratory study was to develop research methods to compare the effectiveness of two video browsing interface designs, or surrogates--one static (storyboard) and one dynamic (slide show)--on two distinct information seeking tasks (gist determination and object recognition). (AEF)
ERIC Educational Resources Information Center
Adolphus, Telima; Omeodu, Doris
2016-01-01
The study investigates the effect of gender and collaborative learning approach on students' conceptual understanding of electromagnetic induction in Secondary Schools in Nigeria. Three research questions and 2 hypotheses were formulated to guide the research. The research design adopted for this study is the quasi-experimental design. In…
Sensitivity study of the monogroove with screen heat pipe design
NASA Technical Reports Server (NTRS)
Evans, Austin L.; Joyce, Martin
1988-01-01
The present sensitivity study of design variable effects on the performance of a monogroove-with-screen heat pipe obtains performance curves for maximum heat-transfer rates vs. operating temperatures by means of a computer code; performance projections for both 1-g and zero-g conditions are obtainable. The variables in question were liquid and vapor channel design, wall groove design, and the number of feed lines in the evaporator and condenser. The effect on performance of three different working fluids, namely ammonia, methanol, and water, were also determined. Greatest sensitivity was to changes in liquid and vapor channel diameters.
Design and analysis issues for economic analysis alongside clinical trials.
Marshall, Deborah A; Hux, Margaret
2009-07-01
Clinical trials can offer a valuable and efficient opportunity to collect the health resource use and outcomes data for economic evaluation. However, economic and clinical studies differ fundamentally in the question they seek to answer. The design and analysis of trial-based cost-effectiveness studies require special consideration, which are reviewed in this article. Traditional randomized controlled trials, using an experimental design with a controlled protocol, are designed to measure safety and efficacy for product registration. Cost-effectiveness analysis seeks to measure effectiveness in the context of routine clinical practice, and requires collection of health care resources to allow estimation of cost over an equal timeframe for each treatment alternative. In assessing suitability of a trial for economic data collection, the comparator treatment and other protocol factors need to reflect current clinical practice and the trial follow-up must be sufficiently long to capture important costs and effects. The broadest available population and a measure of effectiveness reflecting important benefits for patients are preferred for economic analyses. Special analytical issues include dealing with missing and censored cost data, assessing uncertainty of the incremental cost-effectiveness ratio, and accounting for the underlying heterogeneity in patient subgroups. Careful consideration also needs to be given to data from multinational studies since practice patterns can differ across countries. Although clinical trials can be an efficient opportunity to collect data for economic evaluation, careful consideration of the suitability of the study design, and appropriate analytical methods must be applied to obtain rigorous results.
Effect of different children's menu labeling designs on family purchases.
Holmes, Ashley S; Serrano, Elena L; Machin, Jane E; Duetsch, Thomas; Davis, George C
2013-03-01
The majority of labeling studies at restaurants have focused on adults, not children, and utilized cross-sectional data with one menu labeling design, typically calorie information. The aim of this longitudinal study was to examine the effect of three different menu labeling designs for children's meals on total calories and fat selected by families. Each menu was implemented for 2months. Patrons' purchases were tracked from a control menu (with no nutrition information) through all three theoretically-based designs: calorie and fat information; followed by symbols denoting healthier choices; then nutrition bargain price. All menus were created specifically for the study. They featured six combination meals (pre-determined entrees and side items) and a la carte items (entrees and side items that could be ordered separately). Only combination meals contained labeling. Fixed effects models were estimated to detect changes in sales for each menu labeling design compared to the control. Overall, menu labeling did not result in a positive net effect on total calories or fat purchased by families, but resulted in significant shifts in purchases of combination and a la carte meals and healthy and unhealthy options. The most significant impact was seen for nutrition bargain price labeling, the last design. Copyright © 2012 Elsevier Ltd. All rights reserved.
Designing E-Portfolio with ARCS Motivational Design Strategies to Enhance Self-Directed Learning
ERIC Educational Resources Information Center
Mohamad, Syamsul Nor Azlan; Embi, Mohamed Amin; Nordin, Norazah Mohd
2016-01-01
This paper presents the instructional design effect on motivation towards the implementation of e-Portfolio with ARCS Motivational design strategies to enhance self-directed learning. The purpose of the study was to examine the learners' motivation level after the implementation of e-Portfolio. Initially, this paper was conducted to study a total…
Increasing money-counting skills with a student with brain injury: skill and performance deficits.
Fienup, Daniel M; Mudgal, Dipti; Pace, Gary
2013-01-01
Two studies examined the effectiveness of interventions designed to increase money-counting skills of a student with brain injury. Both skill and performance hypotheses were examined. Single subject designs were used to evaluate interventions, including a multiple-baseline across counting paper and coin money (study 1) and a changing criterion design (study 2). In study 1, it was hypothesized that the student had a skill deficit; thus, the participant was taught organizational strategies for counting money. In study 2, a performance deficit was hypothesized and the effects of contingent rewards were evaluated. In study 1, organizational strategies increased organized counting of money, but did not affect counting accuracy. In study 2, contingent rewards increased accurate money counting. When dealing with multi-step behaviours, different components of behaviour can be controlled by different variables, such as skill and performance deficits. Effective academic interventions may need to consider both types of deficits.
The Role of Transfer in Designing Games and Simulations for Health: Systematic Review
Terlouw, Gijs; Wartena, Bard O; van 't Veer, Job TB; Prins, Jelle T; Pierie, Jean Pierre EN
2017-01-01
Background The usefulness and importance of serious games and simulations in learning and behavior change for health and health-related issues are widely recognized. Studies have addressed games and simulations as interventions, mostly in comparison with their analog counterparts. Numerous complex design choices have to be made with serious games and simulations for health, including choices that directly contribute to the effects of the intervention. One of these decisions is the way an intervention is expected to lead to desirable transfer effects. Most designs adopt a first-class transfer rationale, whereas the second class of transfer types seems a rarity in serious games and simulations for health. Objective This study sought to review the literature specifically on the second class of transfer types in the design of serious games and simulations. Focusing on game-like interventions for health and health care, this study aimed to (1) determine whether the second class of transfer is recognized as a road for transfer in game-like interventions, (2) review the application of the second class of transfer type in designing game-like interventions, and (3) assess studies that include second-class transfer types reporting transfer outcomes. Methods A total of 6 Web-based databases were systematically searched by titles, abstracts, and keywords using the search strategy (video games OR game OR games OR gaming OR computer simulation*) AND (software design OR design) AND (fidelity OR fidelities OR transfer* OR behaviour OR behavior). The databases searched were identified as relevant to health, education, and social science. Results A total of 15 relevant studies were included, covering a range of game-like interventions, all more or less mentioning design parameters aimed at transfer. We found 9 studies where first-class transfer was part of the design of the intervention. In total, 8 studies dealt with transfer concepts and fidelity types in game-like intervention design in general; 3 studies dealt with the concept of second-class transfer types and reported effects, and 2 of those recognized transfer as a design parameter. Conclusions In studies on game-like interventions for health and health care, transfer is regarded as a desirable effect but not as a basic principle for design. None of the studies determined the second class of transfer or instances thereof, although in 3 cases a nonliteral transfer type was present. We also found that studies on game-like interventions for health do not elucidate design choices made and rarely provide design principles for future work. Games and simulations for health abundantly build upon the principles of first-class transfer, but the adoption of second-class transfer types proves scarce. It is likely to be worthwhile to explore the possibilities of second-class transfer types, as they may considerably influence educational objectives in terms of future serious game design for health. PMID:29175812
Linking product design to consumer behavior: the moderating role of consumption experience.
Gilal, Naeem Gul; Zhang, Jing; Gilal, Faheem Gul
2018-01-01
Previous investigations of product design broadly link aesthetic, functional, and symbolic designs to sales growth, high turnover, and market share. However, the effect of product design dimensions on consumer willingness-to-buy (WTB) and word-of-mouth (WOM) is virtually ignored by consumer researchers. Similarly, whether the consumption experience can differentiate the effect of the three product design dimensions on WTB and WOM is completely unknown. Using categorization theory as a lens, our study aims to explore the effect of product design dimensions on consumer WTB and WOM directly and indirectly through the moderation of the consumption experience. A convenience sample of (n=357) Chinese and (n=277) Korean shoppers was utilized to test the hypotheses in the fashion apparel industry. Our results showed that the aesthetic design was more prominent in capturing consumer WTB for both Chinese and Koreans. Similarly, the aesthetic design was more salient in enhancing WOM for Chinese, whereas the symbolic design was more promising in terms of improving WOM for Koreans. Further, our moderation results demonstrated that the consumption experience could differentiate the effects of the three product design dimensions on consumer WTB and WOM for Chinese. By contrast, the consumption experience could only interact with the aesthetic design to improve WOM for South Koreans. To the best of authors' knowledge, the present study is one of the initial attempts to link three product design dimensions with consumer WTB and WOM in the fashion apparel context and explored whether consumption experience competes or complement with three product design dimensions to shape consumer WTB and WOM for Chinese and Koreans.
Invited Commentary: Beware the Test-Negative Design.
Westreich, Daniel; Hudgens, Michael G
2016-09-01
In this issue of the Journal, Sullivan et al. (Am J Epidemiol. 2016;184(5):345-353) carefully examine the theoretical justification for use of the test-negative design, a common observational study design, in assessing the effectiveness of influenza vaccination. Using modern causal inference methods (in particular, directed acyclic graphs), they describe different threats to the validity of inferences drawn about the effect of vaccination from test-negative design studies. These threats include confounding, selection bias, and measurement error in either the exposure or the outcome. While confounding and measurement error are common in observational studies, the potential for selection bias inherent in the test-negative design brings into question the validity of inferences drawn from such studies. © The Author 2016. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
NASA Technical Reports Server (NTRS)
Magee, J. P.; Clark, R. D.; Widdison, C. A.
1975-01-01
Conceptual design studies are summarized of tandem-rotor helicopter and tilt-rotor aircraft for a short haul transport mission in the 1985 time frame. Vertical takeoff designs of both configurations are discussed, and the impact of external noise criteria on the vehicle designs, performance, and costs are shown. A STOL design for the tilt-rotor configuration is reported, and the effect of removing the vertical takeoff design constraints on the design parameters, fuel economy, and operating cost is discussed.
Blödt, Susanne; Schützler, Lena; Huang, Wenjing; Pach, Daniel; Brinkhaus, Benno; Hummelsberger, Josef; Kirschbaum, Barbara; Kuhlmann, Kirsten; Lao, Lixing; Liang, Fanrong; Mietzner, Anna; Mittring, Nadine; Müller, Sabine; Paul, Anna; Pimpao-Niederle, Carolina; Roll, Stephanie; Wu, Huangan; Zhu, Jiang; Witt, Claudia M
2013-04-11
Self-care acupressure might be successful in treating menstrual pain, which is common among young women. There is a need for comparative effectiveness research with stakeholder engagement in all phases seeking to address the needs of decision-makers. Our aim was to design a study on the effectiveness of additional self-care acupressure for menstrual pain comparing usual care alone using different methods of stakeholder engagement. The study was designed using multiple mixed methods for stakeholder engagement. Based on the results of a survey and focus group discussion, a stakeholder advisory group developed the study design. Stakeholder engagement resulted in a two-arm pragmatic randomized trial. Two hundred and twenty women aged 18 to 25 years with menstrual pain will be included in the study. Outcome measurement will be done using electronic questionnaires provided by a study specific mobile application (App). Primary outcome will be the mean pain intensity at the days of pain during the third menstruation after therapy start. Stakeholder engagement helped to develop a study design that better serves the needs of decision makers, including an App as a modern tool for both intervention and data collection in a young target group. Clinicaltrials.gov identifier http://NCT01582724.
A framework for reporting on human factor/usability studies of health information technologies.
Peute, Linda W; Driest, Keiko F; Marcilly, Romaric; Bras Da Costa, Sabrina; Beuscart-Zephir, Marie-Catherine; Jaspers, Monique W M
2013-01-01
Increasingly, studies are being published on the potential negative effect of introducing poor designed Health Information Technology (HIT) into clinical settings, relating to technology-induced errors and adverse events. Academic research on HIT design and evaluation is an extremely important source of information in providing new insights into factors contributing to successful system (re)design efforts, system user-friendliness and usability issues and safety critical aspects of HIT design. However, these studies have been inconsistent and incomprehensive in their reporting, complicating the appraisal of outcomes, generalizability of study findings, meta-analysis and harmonization of the available evidence. To improve identification of type of use errors and safety related issues regarding design and implementation of HIT, consensus on issues to be reported on in scientific publications is a necessary step forward. This study presents the first approach to a framework providing a set of principles to follow for comprehensive and unambiguous reporting of HIT design and usability evaluation studies with the objective to reduce variation, improve on the publication reporting quality and proper indexation of these studies. This framework may be helpful in expanding the knowledge base not only concerning the application of Human Factors (HF)/Usability studies of HIT but also improve the knowledge base of how to (re)design and implement effective, efficient and safe HIT.
ERIC Educational Resources Information Center
Kurtulus, Aytac
2013-01-01
The aim of this study was to investigate the effects of web-based interactive virtual tours on the development of prospective mathematics teachers' spatial skills. The study was designed based on experimental method. The "one-group pre-test post-test design" of this method was taken as the research model. The study was conducted with 3rd year…
ERIC Educational Resources Information Center
Kissi, Philip Siaw; Opoku, Gyabaah; Boateng, Sampson Kwadwo
2016-01-01
The aim of the study was to investigate the effect of Microsoft Math Tool (graphical calculator) on students' achievement in the linear function. The study employed Quasi-experimental research design (Pre-test Post-test two group designs). A total of ninety-eight (98) students were selected for the study from two different Senior High Schools…
NASA Technical Reports Server (NTRS)
Martin, E. Dale
1961-01-01
The impact motion of the inflated sphere landing vehicle with a payload centrally supported from the spherical skin by numerous cords has been determined on the assumption of uniform isentropic gas compression during impact. The landing capabilities are determined for a system containing suspension cords of constant cross section. The effects of deviations in impact velocity and initial gas temperature from the design conditions are studied. Also discussed are the effects of errors in the time at which the skin is ruptured. These studies indicate how the design parameters should be chosen to insure reliability of the landing system. Calculations have been made and results are presented for a sphere inflated with hydrogen, landing on the moon in the absence of an atmosphere. The results are presented for one value of the skin-strength parameter.
A new approach for the design of hypersonic scramjet inlets
NASA Astrophysics Data System (ADS)
Raj, N. Om Prakash; Venkatasubbaiah, K.
2012-08-01
A new methodology has been developed for the design of hypersonic scramjet inlets using gas dynamic relations. The approach aims to find the optimal inlet geometry which has maximum total pressure recovery at a prescribed design free stream Mach number. The design criteria for inlet is chosen as shock-on-lip condition which ensures maximum capture area and minimum intake length. Designed inlet geometries are simulated using computational fluid dynamics analysis. The effects of 1D, 2D inviscid and viscous effects on performance of scramjet inlet are reported here. A correction factor in inviscid design is reported for viscous effects to obtain shock-on-lip condition. A parametric study is carried out for the effect of Mach number at the beginning of isolator for the design of scramjet inlets. Present results show that 2D and viscous effects are significant on performance of scramjet inlet. Present simulation results are matching very well with the experimental results available from the literature.
Analysis And Design Of A Water Purification System For The West African Area Of Operation
2016-12-01
harmful metals and in disinfecting the water prior to human consumption . Research conducted proved that the BWS is more cost effective , efficient...and test a feasible and cost- effective prototype of a purification system to the BWS for improved capability. This study uses a design-based and...design. The prototype test results showed that the water purification system performed effectively and efficiently in accordance with the
Beyond the treatment effect: Evaluating the effects of patient preferences in randomised trials.
Walter, S D; Turner, R; Macaskill, P; McCaffery, K J; Irwig, L
2017-02-01
The treatments under comparison in a randomised trial should ideally have equal value and acceptability - a position of equipoise - to study participants. However, it is unlikely that true equipoise exists in practice, because at least some participants may have preferences for one treatment or the other, for a variety of reasons. These preferences may be related to study outcomes, and hence affect the estimation of the treatment effect. Furthermore, the effects of preferences can sometimes be substantial, and may even be larger than the direct effect of treatment. Preference effects are of interest in their own right, but they cannot be assessed in the standard parallel group design for a randomised trial. In this paper, we describe a model to represent the impact of preferences on trial outcomes, in addition to the usual treatment effect. In particular, we describe how outcomes might differ between participants who would choose one treatment or the other, if they were free to do so. Additionally, we investigate the difference in outcomes depending on whether or not a participant receives his or her preferred treatment, which we characterise through a so-called preference effect. We then discuss several study designs that have been proposed to measure and exploit data on preferences, and which constitute alternatives to the conventional parallel group design. Based on the model framework, we determine which of the various preference effects can or cannot be estimated with each design. We also illustrate these ideas with some examples of preference designs from the literature.
William M. Block; Alan B. Franklin; James P. Ward; Joseph L. Ganey; Gary C. White
2001-01-01
Restoration projects are often developed with little consideration for understanding their effects on wildlife. We contend, however, that monitoring treatment effects on wildlife should be an integral component of the design and execution of any management activity, including restoration. Thus, we provide a conceptual framework for the design and implementation of...
ERIC Educational Resources Information Center
Chu, Yuan-Hsiang
2006-01-01
The study investigated the effects of an educational intervention on the variables of awareness, perception, self-efficacy, and behavioral intentions towards technological literacy among students at a College of Design in Southern Taiwan. Using non-probability sampling, 42 freshmen students from the Department of Product Design participated in the…
Effects of Training in Universal Design for Learning on Lesson Plan Development
ERIC Educational Resources Information Center
Spooner, Fred; Baker, Joshua N.; Harris, Amber A.; Ahlgrim-Delzell, Lynn; Browder, Diane M.
2007-01-01
The effects of training in Universal Design for Learning (UDL) on lesson plan development of special and general educators in a college classroom environment were investigated. A true experimental group design with a control group was used for this study. A one-hour teacher training session introduced UDL to the experimental group; the control…
ERIC Educational Resources Information Center
Darwazeh, Afnan N.
A class of 37 in-service government school teachers from the Nablus (Palestine) district was studied to investigate the effects of 18 hours of training in Instructional Designer's Competencies (IDC) on teachers' planning routine, and their students' academic achievement. A questionnaire measured IDC in five domains: analysis, design,…
ERIC Educational Resources Information Center
Chiu, Thomas K. F.; Churchill, Daniel
2016-01-01
Literature suggests using multimedia learning principles in the design of instructional material. However, these principles may not be sufficient for the design of learning objects for concept learning in mathematics. This paper reports on an experimental study that investigated the effects of an instructional approach, which includes two teaching…
DOT National Transportation Integrated Search
2011-07-01
This research focuses on finding a method for creating cost effective and innovative steel bridges in Colorado. The design method that was discovered to create this cost efficiency was designing the beams as simply supported for non-composite dead lo...
The Effectiveness of Scaffolding Design in Training Writing Skills Physics Teaching Materials
ERIC Educational Resources Information Center
Sinaga, Parlindungan; Suhandi, Andi; Liliasari
2015-01-01
Result of field studies showed low writing skill of teachers in teaching material. The root of the problem lies in their inability on translating description of teaching material into writing. This research focused on the effectiveness of scaffolding design. The scaffolding design was tested in the selected topics of physics courses for…
ERIC Educational Resources Information Center
Nuhoglu Kibar, Pinar; Akkoyunlu, Buket
2017-01-01
In this ever more digital and visual world, it has become more vital that students are encouraged to create content during the learning process through effective visualization of their knowledge. Infographics are an effective method for such visualization. The current study therefore proposes an infographic design rubric (IDR) as a criteria-based…
Trade Studies for a Manned High-Power Nuclear Electric Propulsion Vehicle
NASA Technical Reports Server (NTRS)
SanSoucie, Michael; Hull, Patrick V.; Irwin, Ryan W.; TInker, Michael L.; Patton, Bruce W.
2005-01-01
Nuclear electric propulsion (NEP) vehicles will be needed for future manned missions to Mars and beyond. Candidate vehicles must be identified through trade studies for further detailed design from a large array of possibilities. Genetic algorithms have proven their utility in conceptual design studies by effectively searching a large design space to pinpoint unique optimal designs. This research combines analysis codes for NEP subsystems with genetic algorithm-based optimization. Trade studies for a NEP reference mission to the asteroids were conducted to identify important trends, and to determine the effects of various technologies and subsystems on vehicle performance. It was found that the electric thruster type and thruster performance have a major impact on the achievable system performance, and that significant effort in thruster research and development is merited.
Exchangeability in the case-crossover design
Mittleman, Murray A; Mostofsky, Elizabeth
2014-01-01
In cohort and case-control studies, confounding that arises as a result of differences in the distribution of determinants of the outcome between exposure groups leading to non-exchangeability are addressed by restriction, matching or with statistical models. In case-only studies, this issue is addressed by comparing each individual with his/herself. Although case-only designs use self-matching and only include individuals who develop the outcome of interest, issues of non-exchangeability are identical to those that arise in traditional case-control and cohort studies. In this review, we describe one type of case-only design, the case-crossover design, and discuss how the concept of exchangeability can be used to understand issues of confounding, carryover effects, period effects and selection bias in case-crossover studies. PMID:24756878
40 CFR 799.9380 - TSCA reproduction and fertility effects.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 31 2010-07-01 2010-07-01 true TSCA reproduction and fertility effects...-generation reproduction testing and is designed to provide general information concerning the effects of a... subsequent tests. Additionally, since the study design includes in utero as well as postnatal exposure, this...
Effects of Integrating Peace Education in the Nigeria Education System
ERIC Educational Resources Information Center
Olowo, Oluwatoyin Olusegun
2016-01-01
This paper attempted to investigate the effects of integrating Peace Education into Nigeria educational system. Four research questions were designed for the study. The researcher designed an instrument tagged: Questionnaire on effect of Integrating Peace Education (QEIPE). The entire population of two hundred respondents spread across Secondary…
Carracedo-Martínez, Eduardo; Taracido, Margarita; Tobias, Aurelio; Saez, Marc; Figueiras, Adolfo
2010-01-01
Background Case-crossover is one of the most used designs for analyzing the health-related effects of air pollution. Nevertheless, no one has reviewed its application and methodology in this context. Objective We conducted a systematic review of case-crossover (CCO) designs used to study the relationship between air pollution and morbidity and mortality, from the standpoint of methodology and application. Data sources and extraction A search was made of the MEDLINE and EMBASE databases. Reports were classified as methodologic or applied. From the latter, the following information was extracted: author, study location, year, type of population (general or patients), dependent variable(s), independent variable(s), type of CCO design, and whether effect modification was analyzed for variables at the individual level. Data synthesis The review covered 105 reports that fulfilled the inclusion criteria. Of these, 24 addressed methodological aspects, and the remainder involved the design’s application. In the methodological reports, the designs that yielded the best results in simulation were symmetric bidirectional CCO and time-stratified CCO. Furthermore, we observed an increase across time in the use of certain CCO designs, mainly symmetric bidirectional and time-stratified CCO. The dependent variables most frequently analyzed were those relating to hospital morbidity; the pollutants most often studied were those linked to particulate matter. Among the CCO-application reports, 13.6% studied effect modification for variables at the individual level. Conclusions The use of CCO designs has undergone considerable growth; the most widely used designs were those that yielded better results in simulation studies: symmetric bidirectional and time-stratified CCO. However, the advantages of CCO as a method of analysis of variables at the individual level are put to little use. PMID:20356818
Analytical fuel property effects: Small combustors, phase 2
NASA Technical Reports Server (NTRS)
Hill, T. G.; Monty, J. D.; Morton, H. L.
1985-01-01
The effects of non-standard aviation fuels on a typical small gas turbine combustor were studied and the effectiveness of design changes intended to counter the effects of these fuels was evaluated. The T700/CT7 turboprop engine family was chosen as being representative of the class of aircraft power plants desired for this study. Fuel properties, as specified by NASA, are characterized by low hydrogen content and high aromatics levels. No. 2 diesel fuel was also evaluated in this program. Results demonstrated the anticipated higher than normal smoke output and flame radiation intensity with resulting increased metal temperatures on the baseline T700 combustor. Three new designs were evaluated using the non standard fuels. The three designs incorporated enhanced cooling features and smoke reduction features. All three designs, when burning the broad specification fuels, exhibited metal temperatures at or below the baseline combustor temperatures on JP-5. Smoke levels were acceptable but higher than predicted.
Online continuing medical education (CME) for GPs: does it work? A systematic review.
Thepwongsa, Isaraporn; Kirby, Catherine N; Schattner, Peter; Piterman, Leon
2014-10-01
Numerous studies have assessed the effectiveness of online continuing medical education (CME) designed to improve healthcare professionals' care of patients. The effects of online educational interventions targeted at general practitioners (GP), however, have not been systematically reviewed. A computer search was conducted through seven databases for studies assessing changes in GPs' knowledge and practice, or patient outcomes following an online educational intervention. Eleven studies met the eligibility criteria. Most studies (8/11, 72.7%) found a significant improvement in at least one of the following outcomes: satisfaction, knowledge or practice change. There was little evidence for the impact of online CME on patient outcomes. Variability in study design, characteristics of online and outcome measures limited conclusions on the effects of online CME. Online CME could improve GP satisfaction, knowledge and practices but there are very few well-designed studies that focus on this delivery method of GP education.
A Study of Trial and Error Learning in Technology, Engineering, and Design Education
ERIC Educational Resources Information Center
Franzen, Marissa Marie Sloan
2016-01-01
The purpose of this research study was to determine if trial and error learning was an effective, practical, and efficient learning method for Technology, Engineering, and Design Education students at the post-secondary level. A mixed methods explanatory research design was used to measure the viability of the learning source. The study sample was…
ERIC Educational Resources Information Center
Hussin, Husnayati; Bunyarit, Fatimah; Hussein, Ramlah
2009-01-01
Purpose: This study aims to investigate the elements of effective instructional design in an e-learning environment in selected Malaysian higher learning institutions. In addition, the study also seeks to investigate the e-learning use behaviour among these e-learners. Design/methodology/approach: The study used the interview method of data…
ERIC Educational Resources Information Center
Olaniyan, Ademola Olatide; Omosewo, Esther O.; Nwankwo, Levi I.
2015-01-01
This study was designed to investigate the Effect of Polya Problem-Solving Model on Senior School Students' Performance in Current Electricity. It was a quasi experimental study of non- randomized, non equivalent pre-test post-test control group design. Three research questions were answered and corresponding three research hypotheses were tested…
Federal Register 2010, 2011, 2012, 2013, 2014
2013-12-17
... Evaluation and Research, Food and Drug Administration, 10903 New Hampshire Ave., Bldg. 22, Rm. 5411, Silver... surrogate endpoints and study design issues for the in vivo testing of health care antiseptics (Ref. 3... addressed when designing a clinical outcome study of the effectiveness of antiseptic washes in the consumer...
The Effect of Portfolio Assessments on Metacognitive Skills and on Attitudes toward a Course
ERIC Educational Resources Information Center
Gencel, Ilke Evin
2017-01-01
The aim of this study is to determine through teacher candidates' thoughts the effects of a portfolio assessment implementation on their metacognitive skills and attitudes towards a course on measurement and evaluation. Exploratory sequential mixed-methods design is employed within the study. The pretest/posttest control group design was used in…
Effects of Spaced Training in Creative Imagination and Delayed Posttesting on Originality.
ERIC Educational Resources Information Center
Masten, William G.; Hairston, Susan A.
While there is increasing evidence that creativity can be improved through training, the spacing of the training has not been studied. This study assessed the effect of spaced training on the use of creative imagination in 110 undergraduate students. The research design was a randomized delayed posttest-only design. The independent variable was…
Effects of Computer Animation Instructional Package on Students' Achievement in Practical Biology
ERIC Educational Resources Information Center
Hamzat, Abdulrasaq; Bello, Ganiyu; Abimbola, Isaac Olakanmi
2017-01-01
This study examined the effects of computer animation instructional package on secondary school students' achievement in practical biology in Ilorin, Nigeria. The study adopted a pre-test, post-test, control group, non-randomised and nonequivalent quasi-experimental design, with a 2x2x3 factorial design. Two intact classes from two secondary…
Development and Evaluation of the Effectiveness of Computer-Assisted Physics Instruction
ERIC Educational Resources Information Center
Rahman, Mohd. Jasmy Abd; Ismail, Mohd. Arif. Hj.; Nasir, Muhammad
2014-01-01
This study aims to design and develop an interactive software for teaching and learning physics about motion and vectors analysis. This study also assesses its effectiveness in classroom and assesses the learning motivation of SMA Pekanbaru's students. The software is developed using ADDIE Model design and Life Cycle Model and built using the…
ERIC Educational Resources Information Center
Rieben, James C., Jr.
2010-01-01
This study focuses on the effects of relevance and lab design on student learning within the chemistry laboratory environment. A general chemistry conductivity of solutions experiment and an upper level organic chemistry cellulose regeneration experiment were employed. In the conductivity experiment, the two main variables studied were the effect…
Meeting the Need to Belong: Predicting Effects of a Friendship Enrichment Program for Older Women
ERIC Educational Resources Information Center
Stevens, Nan L.; Martina, Camille M. S.; Westerhof, Gerben J.
2006-01-01
Purpose: This study explores the effects of participation in a program designed to enrich friendship and reduce loneliness among women in later life. Several hypotheses based on the need to belong, socioemotional selectivity theory, and the social compensation model were tested. Design and Methods: Study 1 involved two measurement points, one at…
The Effect of Choosing versus Receiving Feedback on College Students' Performance
ERIC Educational Resources Information Center
Cutumisu, Maria; Schwartz, Daniel L.
2016-01-01
This study examines the effect of choosing versus receiving feedback on the learning performance of n = 98 post-secondary students from California on a digital poster design task. The study employs a yoked experimental design where college students are randomly assigned to play a choice-based assessment game, Posterlet, in one of two conditions,…
Hierarchy of Study Designs for Evaluating the Effectiveness of a STEM Education Project or Practice
ERIC Educational Resources Information Center
Coalition for Evidence-Based Policy, 2007
2007-01-01
This document contains a narrative overview of the hierarchy, followed by a one-page graphic summary. The purpose of the hierarchy is to help agency/program officials assess which study designs are capable of producing scientifically-valid evidence on the effectiveness of a STEM education project or practice ("intervention"). More specifically,…
Effect of Ethnochemistry Practices on Secondary School Students' Attitude towards Chemistry
ERIC Educational Resources Information Center
Singh, Indra Sen; Chibuye, Bitwell
2016-01-01
The main purpose of the study was to find out the effect of ethnochemistry practices on secondary school students' attitude towards Chemistry. The design of the study was pre-test post-test control group quasiexperimental design. Two grade 11 intact classes were assigned into experimental and control groups randomly. The total sample size…
ERIC Educational Resources Information Center
Alhajri, Salman
2016-01-01
Purpose: this paper investigates the effectiveness of teaching methods used in graphic design pedagogy in both analogue and digital education systems. Methodology and approach: the paper is based on theoretical study using a qualitative, case study approach. Comparison between the digital teaching methods and traditional teaching methods was…
The Mediator Effects of Conceiving Imagination on Academic Performance of Design Students
ERIC Educational Resources Information Center
Lin, Wei-Sheng; Hsu, Yuling; Liang, Chaoyun
2014-01-01
Three studies were combined to examine the effects of creativity and imagination on the academic performance of design students. Study 1 conducted an exploratory factor analysis to determine the most appropriate structure of the Creativity Capability Scale (CCS) in a sample of 313 college students. The scale was a new self-report measure, and it…
ERIC Educational Resources Information Center
Campbell, Donald P.
2013-01-01
This study investigated the effect of student prior knowledge and feedback type on student achievement and satisfaction in an introductory managerial accounting course using computer-based formative assessment tools. The study involved a redesign of the existing Job Order Costing unit using the ADDIE model of instructional design. The…
Study design elements for rigorous quasi-experimental comparative effectiveness research.
Maciejewski, Matthew L; Curtis, Lesley H; Dowd, Bryan
2013-03-01
Quasi-experiments are likely to be the workhorse study design used to generate evidence about the comparative effectiveness of alternative treatments, because of their feasibility, timeliness, affordability and external validity compared with randomized trials. In this review, we outline potential sources of discordance in results between quasi-experiments and experiments, review study design choices that can improve the internal validity of quasi-experiments, and outline innovative data linkage strategies that may be particularly useful in quasi-experimental comparative effectiveness research. There is an urgent need to resolve the debate about the evidentiary value of quasi-experiments since equal consideration of rigorous quasi-experiments will broaden the base of evidence that can be brought to bear in clinical decision-making and governmental policy-making.
Dollfus, Sonia; Lecardeur, Laurent; Morello, Rémy; Etard, Olivier
2016-01-01
Several meta-analyses have assessed the response of patients with schizophrenia with auditory verbal hallucinations (AVH) to treatment with repetitive transcranial magnetic stimulation (rTMS); however, the placebo response has never been explored. Typically observed in a therapeutic trial, the placebo effect may have a major influence on the effectiveness of rTMS. The purpose of this meta-analysis is to evaluate the magnitude of the placebo effect observed in controlled studies of rTMS treatment of AVH, and to determine factors that can impact the magnitude of this placebo effect, such as study design considerations and the type of sham used. The study included twenty-one articles concerning 303 patients treated by sham rTMS. A meta-analytic method was applied to obtain a combined, weighted effect size, Hedges’s g. The mean weighted effect size of the placebo effect across these 21 studies was 0.29 (P < .001). Comparison of the parallel and crossover studies revealed distinct results for each study design; placebo has a significant effect size in the 13 parallel studies (g = 0.44, P < 10−4), but not in the 8 crossover studies (g = 0.06, P = .52). In meta-analysis of the 13 parallel studies, the 45° position coil showed the highest effect size. Our results demonstrate that placebo effect should be considered a major source of bias in the assessment of rTMS efficacy. These results fundamentally inform the design of further controlled studies, particularly with respect to studies of rTMS treatment in psychiatry. PMID:26089351
Improving the design of maintenance studies for bipolar disorder.
Gitlin, Michael J; Abulseoud, Osama; Frye, Mark A
2010-08-01
In contrast to the trial design of acute mania studies, there is no standard design for bipolar maintenance studies. Over the past 15 years, the design of monotherapy maintenance studies in bipolar disorder has evolved significantly, but recent study designs continue to differ in important ways. We reviewed the design of recent controlled bipolar maintenance studies, using PubMed, from August 2006 to August 2009, examining the strengths and weaknesses of different study design features. Design differences are sufficiently important that the disparate results across maintenance studies may reflect either true differences in medication efficacy or the effects of these design differences on outcome. Design elements such as recent episode polarity, stabilization criteria, using enriched versus nonenriched samples, length of stabilization before randomization, length of experimental phase, and recurrence outcome criteria are critical factors that differ widely across studies and likely play a role in study outcome. As consensus for trial designs for bipolar maintenance therapy is developed, it will be easier to develop algorithms for maintenance treatment based on results from studies as opposed to clinical opinions.
False Dichotomies and Health Policy Research Designs: Randomized Trials Are Not Always the Answer.
Soumerai, Stephen B; Ceccarelli, Rachel; Koppel, Ross
2017-02-01
Some medical scientists argue that only data from randomized controlled trials (RCTs) are trustworthy. They claim data from natural experiments and administrative data sets are always spurious and cannot be used to evaluate health policies and other population-wide phenomena in the real world. While many acknowledge biases caused by poor study designs, in this article we argue that several valid designs using administrative data can produce strong findings, particularly the interrupted time series (ITS) design. Many policy studies neither permit nor require an RCT for cause-and-effect inference. Framing our arguments using Campbell and Stanley's classic research design monograph, we show that several "quasi-experimental" designs, especially interrupted time series (ITS), can estimate valid effects (or non-effects) of health interventions and policies as diverse as public insurance coverage, speed limits, hospital safety programs, drug abuse regulation and withdrawal of drugs from the market. We further note the recent rapid uptake of ITS and argue for expanded training in quasi-experimental designs in medical and graduate schools and in post-doctoral curricula.
Jackson, Matthew T
2015-07-01
Since long term rodent carcinogenicity studies are used to test a very large number of potential tumor endpoints, finding a balance between the control of Type 1 and Type 2 error is challenging. As a result, these studies can suffer from very low power to detect effects of regulatory significance. In the present paper, a new design is proposed in order address this problem. This design is a simple modification of the existing standard designs and uses the same number of animals. Where it differs from the currently used designs is that it uses just three treatment groups rather than four, with the animals concentrated in the control and high dose groups, rather than being equally distributed among the groups. This new design is tested, in a pair of simulation studies over a range of scenarios, against two currently used designs, and against a maximally powerful two group design. It consistently performs at levels close to the optimal design, and except in the case of relatively modest effects and very rare tumors, is found to increase power by 10%-20% over the current designs while maintaining or reducing the Type 1 error rate. Published by Elsevier Inc.
Haber, M; An, Q; Foppa, I M; Shay, D K; Ferdinands, J M; Orenstein, W A
2015-05-01
As influenza vaccination is now widely recommended, randomized clinical trials are no longer ethical in many populations. Therefore, observational studies on patients seeking medical care for acute respiratory illnesses (ARIs) are a popular option for estimating influenza vaccine effectiveness (VE). We developed a probability model for evaluating and comparing bias and precision of estimates of VE against symptomatic influenza from two commonly used case-control study designs: the test-negative design and the traditional case-control design. We show that when vaccination does not affect the probability of developing non-influenza ARI then VE estimates from test-negative design studies are unbiased even if vaccinees and non-vaccinees have different probabilities of seeking medical care against ARI, as long as the ratio of these probabilities is the same for illnesses resulting from influenza and non-influenza infections. Our numerical results suggest that in general, estimates from the test-negative design have smaller bias compared to estimates from the traditional case-control design as long as the probability of non-influenza ARI is similar among vaccinated and unvaccinated individuals. We did not find consistent differences between the standard errors of the estimates from the two study designs.
Dankbaar, Mary E W; Storm, Diana J; Teeuwen, Irene C; Schuit, Stephanie C E
2014-09-01
Introduction There is a demand for more attractive and efficient training programmes in postgraduate health care training. This retrospective study aims to show the effectiveness of a blended versus traditional face-to-face training design. For nurses in postgraduate Acute and Intensive Care training, the effectiveness of a blended course design was compared with a traditional design. Methods In a first pilot study 57 students took a traditional course (2-h lecture and 2-h workshop) and 46 students took a blended course (2-h lecture and 2-h online self-study material). Test results were compared for both groups. After positive results in the pilot study, the design was replicated for the complete programme in Acute and Intensive Care. Now 16 students followed the traditional programme (11 days face-to-face education) and 31 students did the blended programme (7 days face-to-face and 40 h online self-study). An evaluation was done after the pilot and course costs were calculated. Results Results show that the traditional and blended groups were similar regarding the main characteristics and did not differ in learning results for both the pilot and the complete programme. Student evaluations of both designs were positive; however, the blended group were more confident that they had achieved the learning objectives. Training costs were reduced substantially. Conclusion The blended training design offers an effective and attractive training solution, leading to a significant reduction in costs.
Effectiveness guidance document (EGD) for Chinese medicine trials: a consensus document
2014-01-01
Background There is a need for more Comparative Effectiveness Research (CER) on Chinese medicine (CM) to inform clinical and policy decision-making. This document aims to provide consensus advice for the design of CER trials on CM for researchers. It broadly aims to ensure more adequate design and optimal use of resources in generating evidence for CM to inform stakeholder decision-making. Methods The Effectiveness Guidance Document (EGD) development was based on multiple consensus procedures (survey, written Delphi rounds, interactive consensus workshop, international expert review). To balance aspects of internal and external validity, multiple stakeholders, including patients, clinicians, researchers and payers were involved in creating this document. Results Recommendations were developed for “using available data” and “future clinical studies”. The recommendations for future trials focus on randomized trials and cover the following areas: designing CER studies, treatments, expertise and setting, outcomes, study design and statistical analyses, economic evaluation, and publication. Conclusion The present EGD provides the first systematic methodological guidance for future CER trials on CM and can be applied to single or multi-component treatments. While CONSORT statements provide guidelines for reporting studies, EGDs provide recommendations for the design of future studies and can contribute to a more strategic use of limited research resources, as well as greater consistency in trial design. PMID:24885146
ERIC Educational Resources Information Center
Moeyaert, Mariola; Ugille, Maaike; Ferron, John M.; Onghena, Patrick; Heyvaert, Mieke; Beretvas, S. Natasha; Van den Noortgate, Wim
2015-01-01
The purpose of this study is to illustrate the multilevel meta-analysis of results from single-subject experimental designs of different types, including AB phase designs, multiple-baseline designs, ABAB reversal designs, and alternating treatment designs. Current methodological work on the meta-analysis of single-subject experimental designs…
The Value of the Operational Principle in Instructional Design
ERIC Educational Resources Information Center
Gibbons, Andrew S.
2009-01-01
Formal design studies are increasing our insight into design processes, including those of instructional design. Lessons are being learned from other design fields, and new techniques and concepts can be imported as they are demonstrated effective. The purpose of this article is to introduce a design concept--the "operational principle"--for…
A Comparison Study of Second-Order Screening Designs and Their Extension
2013-12-01
H2 97 V. Nonlinear Screening Designs for Defense Testing: An Overview and Case Study 5.1 Introduction “Necessity is the Mother of Invention.” Plato is...involved concepts like design resolution, minimum aber- ration , power, the number of clear (non-confounded) effects, concepts like rotatability
How an Integrative STEM Curriculum Can Benefit Students in Engineering Design Practices
ERIC Educational Resources Information Center
Fan, Szu-Chun; Yu, Kuang-Chao
2017-01-01
STEM-oriented engineering design practice has become recognized increasingly by technology education professionals in Taiwan. This study sought to examine the effectiveness of the application of an integrative STEM approach within engineering design practices in high school technology education in Taiwan. A quasi-experimental study was conducted…
Optimal Design for Two-Level Random Assignment and Regression Discontinuity Studies
ERIC Educational Resources Information Center
Rhoads, Christopher H.; Dye, Charles
2016-01-01
An important concern when planning research studies is to obtain maximum precision of an estimate of a treatment effect given a budget constraint. When research designs have a "multilevel" or "hierarchical" structure changes in sample size at different levels of the design will impact precision differently. Furthermore, there…
The Neuroprotective Effects of Thymoquinone: A Review
Farkhondeh, Tahereh; Samarghandian, Saeed; Samini, Fariborz
2018-01-01
Thymoquinone (TQ), one of the main components active of Nigella sativa, exhibited very useful biomedical effects such as anti-inflammatory, antioxidant, antimicrobial, antiparasitic, anticancer, hypoglycemic, antihypertensive, and antiasthmatic effects. There are several studies about pharmacological activities of TQ but its neuroprotection effects are not fully described. The literature search has indicated many studies pertaining to the effects of TQ in neurological problems such as epilepsy, parkinsonism, anxiety, and improvement of learning and memory, and so on. In addition, TQ protected brain cells from various injuries due to its antioxidant, anti-inflammatory, and apoptotic effects in cell line and experimental animal models. The present study has been designed to review the scientific literature about the pharmacological activities of TQ to the neurological diseases. This study purposed that although experimental studies indicated the beneficial effects of TQ against nervous system problems, better designed clinical trials in humans are needed to confirm these effects. PMID:29662431
ERIC Educational Resources Information Center
Atli, Abdullah
2016-01-01
The study aimed to research the effect of career counseling sessions based on trait-factor theory on the career maturity and career indecision levels of high school students. "Single group pretest-posttest test design", one of the weaker test designs, was utilized in the study. The study was conducted with 57 students in Malatya city…
Hysong, Sylvia J; Kell, Harrison J; Petersen, Laura A; Campbell, Bryan A; Trautner, Barbara W
2017-04-01
Audit and feedback (A&F) is a common intervention used to change healthcare provider behaviour and, thus, improve healthcare quality. Although A&F can be effective its effectiveness varies, often due to the details of how A&F interventions are implemented. Some have suggested that a suitable conceptual framework is needed to organise the elements of A&F and also explain any observed differences in effectiveness. Through two examples from applied research studies, this article demonstrates how a suitable explanatory theory (in this case Kluger & DeNisi's Feedback Intervention Theory (FIT)) can be systematically applied to design better feedback interventions in healthcare settings. Case 1: this study's objective was to reduce inappropriate diagnosis of catheter-associated urinary tract infections (CAUTI) in inpatient wards. Learning to identify the correct clinical course of action from the case details was central to this study; consequently, the feedback intervention featured feedback elements that FIT predicts would best activate learning processes (framing feedback in terms of group performance and providing of correct solution information). We designed a highly personalised, interactive, one-on-one intervention with healthcare providers to improve their capacity to distinguish between CAUTI and asymptomatic bacteruria (ASB) and treat ASB appropriately. Case 2: Simplicity and scalability drove this study's intervention design, employing elements that FIT predicted positively impacted effectiveness yet still facilitated deployment and scalability (eg, delivered via computer, delivered in writing). We designed a web-based, report-style feedback intervention to help primary care physicians improve their care of patients with hypertension. Both studies exhibited significant improvements in their desired outcome and in both cases interventions were received positively by feedback recipients. A&F has been a popular, yet inconsistently implemented and variably effective tool for changing healthcare provider behaviour and, improving healthcare quality. Through the systematic use of theory such as FIT, robust feedback interventions can be designed that yield greater effectiveness. Future work should look to comparative effectiveness of specific design elements and contextual factors that identify A&F as the optimal intervention to effectuate healthcare provider behaviour change. NCT01052545, NCT00302718; post-results. 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/.
Genetic dissection of main and epistatic effects of QTL based on augmented triple test cross design
Zhang, Zheng; Dai, Zhijun; Chen, Yuan; Yuan, Xiong; Yuan, Zheming; Tang, Wenbang; Li, Lanzhi; Hu, Zhongli
2017-01-01
The use of heterosis has considerably increased the productivity of many crops; however, the biological mechanism underpinning the technique remains elusive. The North Carolina design III (NCIII) and the triple test cross (TTC) are powerful and popular genetic mating design that can be used to decipher the genetic basis of heterosis. However, when using the NCIII design with the present quantitative trait locus (QTL) mapping method, if epistasis exists, the estimated additive or dominant effects are confounded with epistatic effects. Here, we propose a two-step approach to dissect all genetic effects of QTL and digenic interactions on a whole genome without sacrificing statistical power based on an augmented TTC (aTTC) design. Because the aTTC design has more transformation combinations than do the NCIII and TTC designs, it greatly enriches the QTL mapping for studying heterosis. When the basic population comprises recombinant inbred lines (RIL), we can use the same materials in the NCIII design for aTTC-design QTL mapping with transformation combination Z1, Z2, and Z4 to obtain genetic effect of QTL and digenic interactions. Compared with RIL-based TTC design, RIL-based aTTC design saves time, money, and labor for basic population crossed with F1. Several Monte Carlo simulation studies were carried out to confirm the proposed approach; the present genetic parameters could be identified with high statistical power, precision, and calculation speed, even at small sample size or low heritability. Additionally, two elite rice hybrid datasets for nine agronomic traits were estimated for real data analysis. We dissected the genetic effects and calculated the dominance degree of each QTL and digenic interaction. Real mapping results suggested that the dominance degree in Z2 that mainly characterize heterosis showed overdominance and dominance for QTL and digenic interactions. Dominance and overdominance were the major genetic foundations of heterosis in rice. PMID:29240818
Gilal, Faheem Gul; Zhang, Jian; Gilal, Naeem Gul; Gilal, Rukhsana Gul
2018-01-01
Background The present study integrates self-determined needs satisfaction into a relationship between product design (eg, aesthetic, functional, and symbolic design) and consumer behavior (eg, willingness-to-pay [WTP] a premium and negative word-of-mouth [WOM]) and to explore whether gender can differentiate the effects of aesthetic, functional, and symbolic product designs on self-determined needs satisfaction. Methods To this end, participants from Pakistan and China were recruited, and the hypotheses for this study were tested using structural equation modeling and SPSS-PROCESS. Results The effects of three product designs on self-determined needs satisfaction were significantly positive across samples. The results further show that self-determined needs satisfaction had the strongest positive effect on WTP a premium and the strongest negative effect on vindictive WOM for Pakistanis. Self-determined needs frustration had the strongest negative effect on the WTP a premium for Chinese participants and an equivalent magnitude effect on vindictive WOM for Pakistani and Chinese participants. The cross-cultural gender-specific findings revealed that Pakistani men are more aesthetic and hedonic than women in Pakistan. Surprisingly, Chinese women resemble Pakistani men in the sense that they prefer aesthetically pleasing products. Chinese men resemble Pakistani women in terms of little interest in symbolic products, whereas Chinese women and Pakistani men respond similarly regarding their decisions to choose symbolic products. Conclusion To the best of the authors’ knowledge, the present study is one of the initial attempts to integrate self-determined needs into the relationship between product design and consumer WTP a premium and WOM, and further explore cross-cultural gender-specific differences across Pakistan and China. The findings of the present study may help international marketers in terms of segmenting, targeting, and positioning their markets. PMID:29922102
Ethnography by Design: On Goals and Mediating Artefacts
ERIC Educational Resources Information Center
Segelström, Fabian; Holmlid, Stefan
2015-01-01
Design ethnography is the appropriation of ethnography for the purposes of informing design. This paper investigates the effects of these appropriations, through a comparative study of how designers and anthropologists approach the same field site and by a review of new techniques introduced by designers to do ethnography. The techniques reviewed…
Linking product design to consumer behavior: the moderating role of consumption experience
Gilal, Naeem Gul; Zhang, Jing; Gilal, Faheem Gul
2018-01-01
Background Previous investigations of product design broadly link aesthetic, functional, and symbolic designs to sales growth, high turnover, and market share. However, the effect of product design dimensions on consumer willingness-to-buy (WTB) and word-of-mouth (WOM) is virtually ignored by consumer researchers. Similarly, whether the consumption experience can differentiate the effect of the three product design dimensions on WTB and WOM is completely unknown. Using categorization theory as a lens, our study aims to explore the effect of product design dimensions on consumer WTB and WOM directly and indirectly through the moderation of the consumption experience. Methods A convenience sample of (n=357) Chinese and (n=277) Korean shoppers was utilized to test the hypotheses in the fashion apparel industry. Results Our results showed that the aesthetic design was more prominent in capturing consumer WTB for both Chinese and Koreans. Similarly, the aesthetic design was more salient in enhancing WOM for Chinese, whereas the symbolic design was more promising in terms of improving WOM for Koreans. Further, our moderation results demonstrated that the consumption experience could differentiate the effects of the three product design dimensions on consumer WTB and WOM for Chinese. By contrast, the consumption experience could only interact with the aesthetic design to improve WOM for South Koreans. Conclusion To the best of authors’ knowledge, the present study is one of the initial attempts to link three product design dimensions with consumer WTB and WOM in the fashion apparel context and explored whether consumption experience competes or complement with three product design dimensions to shape consumer WTB and WOM for Chinese and Koreans. PMID:29785145
ERIC Educational Resources Information Center
Martens, Brian K.; Eckert, Tanya L.; Bradley, Tracy A.; Ardoin, Scott P.
1999-01-01
Discusses the benefits of using brief experimental analysis to aid in treatment selection, identifies the forms of treatment that are most appropriate for this type of analysis, and describes key design elements for comparing treatments. Presents a study demonstrating the use of these design elements to identify an effective intervention for two…
ERIC Educational Resources Information Center
Yucel, Elif Ozata; Ozkan, Muhlis
2015-01-01
This study aims to develop an instructional design whereby ecosystem, biodiversity, and environmental issues are addressed with a holistic approach that provides more efficient teaching as well as to test the effectiveness of this design. A literature review was carried out and need-assessment was firstly made using the Readiness Test. This review…
ERIC Educational Resources Information Center
Schrand, Tom; Eliason, John
2012-01-01
To examine the differences between feedback practices in liberal arts courses and in design courses, we surveyed 373 students with experiences of both. Our study found that students perceived the feedback they received in design courses as more effective in advancing their learning, and that the emotional effects of feedback presented verbally and…
An Effective Introduction to Technology and Design in Norwegian Primary Education
ERIC Educational Resources Information Center
Kirkeby, Pal J.
2010-01-01
How can young pupils get "An effective introduction" to technology and design at the primary level in the Norwegian context? This question is highlighted with examples based on case studies at five classes in two schools doing their first technology and design project at grades 1 or 2 (age 6-8 years). The project was about air rockets.…
ERIC Educational Resources Information Center
Sarfo, Frederick Kwaku; Eshun, Grace; Elen, Jan; Adentwi, Kobina Impraim
2014-01-01
Introduction: In this study, the effectiveness of two different interventions was investigated. The effects of a concrete abstract intervention and a regular method of teaching intervention were compared. Both interventions were designed in line with the specifications of classical principles of instructional design for learning mathematics in the…
Huang, Jun; Kaul, Goldi; Cai, Chunsheng; Chatlapalli, Ramarao; Hernandez-Abad, Pedro; Ghosh, Krishnendu; Nagi, Arwinder
2009-12-01
To facilitate an in-depth process understanding, and offer opportunities for developing control strategies to ensure product quality, a combination of experimental design, optimization and multivariate techniques was integrated into the process development of a drug product. A process DOE was used to evaluate effects of the design factors on manufacturability and final product CQAs, and establish design space to ensure desired CQAs. Two types of analyses were performed to extract maximal information, DOE effect & response surface analysis and multivariate analysis (PCA and PLS). The DOE effect analysis was used to evaluate the interactions and effects of three design factors (water amount, wet massing time and lubrication time), on response variables (blend flow, compressibility and tablet dissolution). The design space was established by the combined use of DOE, optimization and multivariate analysis to ensure desired CQAs. Multivariate analysis of all variables from the DOE batches was conducted to study relationships between the variables and to evaluate the impact of material attributes/process parameters on manufacturability and final product CQAs. The integrated multivariate approach exemplifies application of QbD principles and tools to drug product and process development.
Butler, Christopher C.; Coenen, Samuel; Saville, Benjamin R.; Cook, Johanna; van der Velden, Alike; Homes, Jane; de Jong, Menno; Little, Paul; Goossens, Herman; Ieven, Margareta; Francis, Nick; Moons, Pieter; Bongard, Emily; Verheij, Theo
2018-01-01
ALIC4E is the first publicly funded, multicountry, pragmatic study determining whether antivirals should be routinely prescribed for influenza-like illness in primary care. The trial aims to go beyond determining the average treatment effect in a population to determining effects in patients with combinations of participant characteristics (age, symptom duration, illness severity, and comorbidities). It is one of the first platform, response-adaptive, open trial designs implemented in primary care, and this article aims to provide an accessible description of key aspects of the study design. 1) The platform design allows the study to remain relevant to evolving circumstances, with the ability to add treatment arms. 2) Response adaptation allows the proportion of participants with key characteristics allocated to study arms to be altered during the course of the trial according to emerging outcome data, so that participants' information will be most useful, and increasing their chances of receiving the trial intervention that will be most effective for them. 3) Because the possibility of taking placebos influences participant expectations about their treatment, and determining effects of the interventions on patient help seeking and adherence behaviour in real-world care is critical to estimates of cost-effectiveness, ALIC4E is an open-label trial. PMID:29761108
Evaluating Intervention Effects in a Diagnostic Classification Model Framework
ERIC Educational Resources Information Center
Madison, Matthew J.; Bradshaw, Laine
2018-01-01
The evaluation of intervention effects is an important objective of educational research. One way to evaluate the effectiveness of an intervention is to conduct an experiment that assigns individuals to control and treatment groups. In the context of pretest/posttest designed studies, this is referred to as a control-group pretest/posttest design.…
Heat effects on drug delivery across human skin
Hao, Jinsong; Ghosh, Priyanka; Li, S. Kevin; Newman, Bryan; Kasting, Gerald B.; Raney, Sam G.
2016-01-01
Introduction Exposure to heat can impact the clinical efficacy and/or safety of transdermal and topical drug products. Understanding these heat effects and designing meaningful in vitro and in vivo methods to study them are of significant value to the development and evaluation of drug products dosed to the skin. Areas covered This review provides an overview of the underlying mechanisms and the observed effects of heat on the skin and on transdermal/topical drug delivery, thermoregulation and heat tolerability. The designs of several in vitro and in vivo heat effect studies and their results are reviewed. Expert opinion There is substantial evidence that elevated temperature can increase transdermal/topical drug delivery. However, in vitro and in vivo methods reported in the literature to study heat effects of transdermal/topical drug products have utilized inconsistent study conditions, and in vitro models require better characterization. Appropriate study designs and controls remain to be identified, and further research is warranted to evaluate in vitro-in vivo correlations and the ability of in vitro models to predict in vivo effects. The physicochemical and pharmacological properties of the drug(s) and the drug product, as well as dermal clearance and heat gradients may require careful consideration. PMID:26808472
Effectiveness of simulation for improvement in self-efficacy among novice nurses: a meta-analysis.
Franklin, Ashley E; Lee, Christopher S
2014-11-01
The influence of simulation on self-efficacy for novice nurses has been reported inconsistently in the literature. Effect sizes across studies were synthesized using random-effects meta-analyses. Simulation improved self-efficacy in one-group, pretest-posttest studies (Hedge's g=1.21, 95% CI [0.63, 1.78]; p<0.001). Simulation also was favored over control teaching interventions in improving self-efficacy in studies with experimental designs (Hedge's g=0.27, 95% CI [0.1, 0.44]; p=0.002). In nonexperimental designs, consistent conclusions about the influence of simulation were tempered by significant between-study differences in effects. Simulation is effective at increasing self-efficacy among novice nurses, compared with traditional control groups. Copyright 2014, SLACK Incorporated.
ERIC Educational Resources Information Center
Karakis, Hilal; Karamete, Aysen; Okçu, Aydin
2016-01-01
This study examined the effects that computer-assisted instruction had on students' attitudes toward a mathematics lesson and toward learning mathematics with computer-assisted instruction. The computer software we used was based on the ASSURE Instructional Systems Design and the ARCS Model of Motivation, and the software was designed to teach…
NASA Astrophysics Data System (ADS)
Goncher, Andrea M.
thResearch on engineering design is a core area of concern within engineering education, and a fundamental understanding of how engineering students approach and undertake design is necessary in order to develop effective design models and pedagogies. This dissertation contributes to scholarship on engineering design by addressing a critical, but as yet underexplored, problem: how does the context in which students design shape their design practices? Using a qualitative study comprising of video data of design sessions, focus group interviews with students, and archives of their design work, this research explored how design decisions and actions are shaped by context, specifically the context of higher education. To develop a theoretical explanation for observed behavior, this study used the nested structuration. framework proposed by Perlow, Gittell, & Katz (2004). This framework explicated how teamwork is shaped by mutually reinforcing relationships at the individual, organizational, and institutional levels. I appropriated this framework to look specifically at how engineering students working on a course-related design project identify constraints that guide their design and how these constraints emerge as students interact while working on the project. I first identified and characterized the parameters associated with the design project from the student perspective and then, through multi-case studies of four design teams, I looked at the role these parameters play in student design practices. This qualitative investigation of first-year engineering student design teams revealed mutual and interconnected relationships between students and the organizations and institutions that they are a part of. In addition to contributing to research on engineering design, this work provides guidelines and practices to help design educators develop more effective design projects by incorporating constraints that enable effective design and learning. Moreover, I found that when appropriated in the context of higher education, multiple sublevels existed within nested structuration's organizational context and included course-level and project-level factors. The implications of this research can be used to improve the design of engineering course projects as well as the design of research efforts related to design in engineering education.
Importance of placebo effect in cough clinical trials.
Eccles, Ron
2010-01-01
Cough is a unique symptom because, unlike sneeze and other symptoms, it can be under voluntary control and this complicates clinical trials on cough medicines. All over-the-counter cough medicines (OTC) are very effective treatments because of their placebo effect. The placebo effect is enhanced by expectancy related to advertising, brand, packaging, and formulation. This placebo effect creates a problem for the conduct of clinical trials on OTC cough medicines that attempt to demonstrate the efficacy of a pharmacological agent above that of any placebo effect. Up to 85% of the efficacy of some cough medicines can be attributed to a placebo effect. The placebo effect apparent in clinical trials consists of several components: natural recovery, regression of cough response toward mean, demulcent effect, effect of sweetness, voluntary control, and effects related to expectancy and meaning of the treatment. The placebo effect has been studied most in the pain model, and placebo analgesia is reported to depend on the activation of endogenous opioid systems in the brain; this model may be applicable to cough. A balanced placebo design may help to control for the placebo effect, but this trial design may not be acceptable due to deception of patients. The placebo effect in clinical trials may be controlled by use of a crossover design, where feasible, and the changes in the magnitude of the placebo effect in this study design are discussed.
2015-01-01
over data-dense regions. After that, a perfect twin data assimilation experiment framework is designed to study the effect of the GDF on the state...is designed to study the effect of the GDF on the state estimation based on an intermediate coupled model. In this framework, the assimilation model...observation. Considering = , (4) is equal to () = 1 2 + 1 2 ( − ) −1 ( − ) . (5) The effect of in (5) can
Evaluating sediment capture rates for different sediment basin designs.
DOT National Transportation Integrated Search
2007-08-01
The effectiveness of sediment control devices was studied on a large NC DOT project to determine the : effects of different designs and conditions. Flow and sediment content of water exiting six different traps : and basins were measured and the amou...
Studies In Test Design: Annual Report.
ERIC Educational Resources Information Center
Quellmalz, Edys; And Others
This document contains the following manuscripts: "Effects of Alternate Scoring Options on the Classification of Entering Freshmen Writing Competencies," by Edys Quellmalz and Eva Baker; "Implications of Learning Research for Designing Competency Based Assessment," by Edys Quellmalz; "Effects of Alternative Discourse and…
Robertson, Michelle M; Huang, Yueng-Hsiang
2006-01-01
The effects of a workplace design and training intervention and the relationships between perceived satisfaction of office workplace design factors (layout and storage) and work performance measures (individual performance, group collaboration and effectiveness) were studied with 120 office workers using the Workplace Environment Questionnaire. Further, we examined whether environmental control had a direct effect on work performance, and then explored whether environmental control mediated or moderated the relationship between workplace design factors and work performance. Results showed a significant, positive impact of the intervention on environmental satisfaction for workstation layout. Satisfaction with workstation layout had a significant relationship with individual performance, group collaboration and effectiveness; and satisfaction with workstation storage had a significant relationship with individual performance and group collaboration. Environmental control had a direct impact on individual performance and group collaboration; whereas, the mediating and moderating effects of environmental control on the relationship between workplace design factors and outcome variables were not significant.
ERIC Educational Resources Information Center
Ogbuanya, T. C.; Owodunni, A. S.
2015-01-01
This study was designed to determine the effect of reflective inquiry instructional technique on achievement of students in Technical Colleges. The study adopted a pre-test, post-test, non-equivalent control group, quasi-experimental research design which involved groups of students in their intact class assigned to experimental group and control…
ERIC Educational Resources Information Center
Casem, Remalyn Q.
2016-01-01
This study aimed to determine the effects of flipped instruction on the performance and attitude of high school students in Mathematics. The study made use of the true experimental design, specifically the pretest-posttest control group design. There were two instruments used to gather data, the pretest-posttest which was subjected to validity and…
ERIC Educational Resources Information Center
Karakus, Fatih; Aydin, Bünyamin
2017-01-01
This study aimed at determining the effects of using a computer algebra system (CAS) on undergraduate students' spatial visualization skills in a calculus course. This study used an experimental design. The "one group pretest-posttest design" was the research model. The participants were 41 sophomore students (26 female and 15 male)…
ERIC Educational Resources Information Center
Hung, Yen-Chu
2012-01-01
The instructional value of web-based education systems has been an important area of research in information systems education. This study investigates the effect of various teaching methods on program design learning for students with specific learning styles in web-based education systems. The study takes first-year Computer Science and…
ERIC Educational Resources Information Center
Negley, Sandra Anne
The main purpose of this study was to determine and describe the effects of the comprehension component of the criterion-referenced reading program, Wisconsin Design for Reading Skills Development (WDRSD), on reading achievement and self-concept of sixth-grade students. Parametric techniques were employed in a quasi-experimental study involving 44…
ERIC Educational Resources Information Center
Cooper, Nancy A.
2014-01-01
The primary intent of this study was to explore the effect between teachers' training, intervention strategies, and the academic achievement of K-5 ADHD students. The study design employed a mixed research design. The quantitative method focused on collecting data from certified regular and special-education teachers. Additionally, effects were…
ERIC Educational Resources Information Center
Bonner, William Bryant, III
2017-01-01
The purpose of this qualitative case study based upon the theories of technology adoption and technology integration planning (TIP) with the focus on design and development was to understand design features that encourage effectiveness and efficiency for using online individual education plans (IEP) along with the online IEP lived experiences of…
ERIC Educational Resources Information Center
Lai, Mark H. C.; Kwok, Oi-man
2015-01-01
Educational researchers commonly use the rule of thumb of "design effect smaller than 2" as the justification of not accounting for the multilevel or clustered structure in their data. The rule, however, has not yet been systematically studied in previous research. In the present study, we generated data from three different models…
ERIC Educational Resources Information Center
Al-Zahrani, Mona Abdullah Bakheet
2011-01-01
The current study aimed at investigating the effectiveness of keyword-based instruction in enhancing English vocabulary achievement and retention of intermediate stage pupils with different working memory capacities. The study adopted a quasi experimental design employing two groups (experimental and control). The design included an independent…
ERIC Educational Resources Information Center
Bozdogan, Aykut Emre
2016-01-01
The study aimed at examining the effect of the planetarium trip on metaphors developed by the pre-service science teachers about the concept of planetarium. Within this context of the study, a trip was organized to Ondokuz Mayis University (OMU) Planetarium. Pretest-posttest control group design, one of the experimental designs, was used in the…
ERIC Educational Resources Information Center
Ciftci, S. Koza; Karadag, Engin; Akdal, Pinar
2014-01-01
The purpose of this study was to determine the effect of statistics instruction using computer-based tools, on statistics anxiety, attitude, and achievement. This study was designed as quasi-experimental research and the pattern used was a matched pre-test/post-test with control group design. Data was collected using three scales: a Statistics…
ERIC Educational Resources Information Center
Dankbaar, Mary E. W.; Alsma, Jelmer; Jansen, Els E. H.; van Merrienboer, Jeroen J. G.; van Saase, Jan L. C. M.; Schuit, Stephanie C. E.
2016-01-01
Simulation games are becoming increasingly popular in education, but more insight in their critical design features is needed. This study investigated the effects of fidelity of open patient cases in adjunct to an instructional e-module on students' cognitive skills and motivation. We set up a three-group randomized post-test-only design: a…
ERIC Educational Resources Information Center
Anliak, Sakire; Sahin, Derya
2010-01-01
The present observational study was designed to evaluate the effectiveness of the I Can Problem Solve (ICPS) programme on behavioural change from aggression to pro-social behaviours by using the DECB rating scale. Non-participant observation method was used to collect data in pretest-training-posttest design. It was hypothesised that the ICPS…
ERIC Educational Resources Information Center
Mahoney, Diane Feeney; Tarlow, Barbara J.; Jones, Richard N.
2003-01-01
Purpose: We determine the main outcome effects of a 12-month computer-mediated automated interactive voice response (IVR) intervention designed to assist family caregivers managing persons with disruptive behaviors related to Alzheimer's disease (AD). Design and Methods: We conducted a randomized controlled study of 100 caregivers, 51 in the usual…
Instructional Coaching at Selected Middle Schools in South Texas and Effects on Student Achievement
ERIC Educational Resources Information Center
Garcia, SantaPaula Gama; Jones, Don; Holland, Glenda; Mundy, Marie-Anne
2013-01-01
The purpose of this study was to compare two middle schools in one school district in south Texas to determine if presence or absence of instructional coaches has an effect on student achievement. The research design was a quantitative pre experimental study: a nonequivalent (posttest only) control group design in which the experimental group and…
The Role of Transfer in Designing Games and Simulations for Health: Systematic Review.
Kuipers, Derek A; Terlouw, Gijs; Wartena, Bard O; van 't Veer, Job Tb; Prins, Jelle T; Pierie, Jean Pierre En
2017-11-24
The usefulness and importance of serious games and simulations in learning and behavior change for health and health-related issues are widely recognized. Studies have addressed games and simulations as interventions, mostly in comparison with their analog counterparts. Numerous complex design choices have to be made with serious games and simulations for health, including choices that directly contribute to the effects of the intervention. One of these decisions is the way an intervention is expected to lead to desirable transfer effects. Most designs adopt a first-class transfer rationale, whereas the second class of transfer types seems a rarity in serious games and simulations for health. This study sought to review the literature specifically on the second class of transfer types in the design of serious games and simulations. Focusing on game-like interventions for health and health care, this study aimed to (1) determine whether the second class of transfer is recognized as a road for transfer in game-like interventions, (2) review the application of the second class of transfer type in designing game-like interventions, and (3) assess studies that include second-class transfer types reporting transfer outcomes. A total of 6 Web-based databases were systematically searched by titles, abstracts, and keywords using the search strategy (video games OR game OR games OR gaming OR computer simulation*) AND (software design OR design) AND (fidelity OR fidelities OR transfer* OR behaviour OR behavior). The databases searched were identified as relevant to health, education, and social science. A total of 15 relevant studies were included, covering a range of game-like interventions, all more or less mentioning design parameters aimed at transfer. We found 9 studies where first-class transfer was part of the design of the intervention. In total, 8 studies dealt with transfer concepts and fidelity types in game-like intervention design in general; 3 studies dealt with the concept of second-class transfer types and reported effects, and 2 of those recognized transfer as a design parameter. In studies on game-like interventions for health and health care, transfer is regarded as a desirable effect but not as a basic principle for design. None of the studies determined the second class of transfer or instances thereof, although in 3 cases a nonliteral transfer type was present. We also found that studies on game-like interventions for health do not elucidate design choices made and rarely provide design principles for future work. Games and simulations for health abundantly build upon the principles of first-class transfer, but the adoption of second-class transfer types proves scarce. It is likely to be worthwhile to explore the possibilities of second-class transfer types, as they may considerably influence educational objectives in terms of future serious game design for health. ©Derek A Kuipers, Gijs Terlouw, Bard O Wartena, Job TB van 't Veer, Jelle T Prins, Jean Pierre EN Pierie. Originally published in JMIR Serious Games (http://games.jmir.org), 24.11.2017.
Kulig, Kornelia; Pomrantz, Amy B; Burnfield, Judith M; Reischl, Stephen F; Mais-Requejo, Susan; Thordarson, David B; Smith, Ronald W
2006-01-01
Background Posterior tibialis tendon dysfunction (PTTD) is a common cause of foot pain and dysfunction in adults. Clinical observations strongly suggest that the condition is progressive. There are currently no controlled studies evaluating the effectiveness of exercise, orthoses, or orthoses and exercise on Stage I or IIA PTTD. Our study will explore the effectiveness of an eccentric versus concentric strengthening intervention to results obtained with the use of orthoses alone. Findings from this study will guide the development of more efficacious PTTD intervention programs and contribute to enhanced function and quality of life in persons with posterior tibialis tendon dysfunction. Methods/design This paper presents the rationale and design for a randomized clinical trial evaluating the effectiveness of a treatment regime for the non-operative management of Stage I or IIA PTTD. Discussion We have presented the rationale and design for an RCT evaluating the effectiveness of a treatment regimen for the non-operative management of Stage I or IIA PTTD. The results of this trial will be presented as soon as they are available. PMID:16756656
Pawlowski, Charlotte Skau; Winge, Laura; Carroll, Sidse; Schmidt, Tanja; Wagner, Anne Margrethe; Nørtoft, Kamilla Pernille Johansen; Lamm, Bettina; Kural, René; Schipperijn, Jasper; Troelsen, Jens
2017-05-19
A limited amount of research has examined the effect of changing public open spaces on active living. This paper will present the study protocol of a community-based intervention study co-designed in an interdisciplinary collaboration with community members to develop urban installations highly tailored to promote active living among children (10-13-years-old) and seniors (>60-years-old) in a deprived neighbourhood in Copenhagen. The study builds on a quasi-experimental study design with two sub-studies: 1) a children study and 2) a senior study. The interventions will be developed, designed and implemented in collaboration with local children and seniors, respectively, using different co-design tools and methods. We will evaluate the effect of the interventions on children's and senior's use of the new-built urban installations using accelerometers in combination with GPS as well as systematic observation using the System for Observing Play and Recreation in Communities (SOPARC). A process evaluation with focus groups consisting of the various stakeholders in the two sub-studies will be used to gain knowledge of the intervention processes. The paper presents new approaches in the field of public open space interventions through interdisciplinary collaboration, participatory co-design approach and combination of measurements. Using both effect and process evaluations the study will provide unique insights in the role and importance of the interdisciplinary collaboration, participatory processes, and tailoring changes in public open space to local needs and wishes. These results can be used to guide urban renewal projects in deprived neighbourhoods in the future. Retrospectively registered with study ID ISRCTN50036837 . Date of registration: 16 December 2016.
The Effect of Framework Design on Stress Distribution in Implant-Supported FPDs: A 3-D FEM Study
Eraslan, Oguz; Inan, Ozgur; Secilmis, Asli
2010-01-01
Objectives: The biomechanical behavior of the superstructure plays an important role in the functional longevity of dental implants. However, information about the influence of framework design on stresses transmitted to the implants and supporting tissues is limited. The purpose of this study was to evaluate the effects of framework designs on stress distribution at the supporting bone and supporting implants. Methods: In this study, the three-dimensional (3D) finite element stress analysis method was used. Three types of 3D mathematical models simulating three different framework designs for implant-supported 3-unit posterior fixed partial dentures were prepared with supporting structures. Convex (1), concave (2), and conventional (3) pontic framework designs were simulated. A 300-N static vertical occlusal load was applied on the node at the center of occlusal surface of the pontic to calculate the stress distributions. As a second condition, frameworks were directly loaded to evaluate the effect of the framework design clearly. The Solidworks/Cosmosworks structural analysis programs were used for finite element modeling/analysis. Results: The analysis of the von Mises stress values revealed that maximum stress concentrations were located at the loading areas for all models. The pontic side marginal edges of restorations and the necks of implants were other stress concentration regions. There was no clear difference among models when the restorations were loaded at occlusal surfaces. When the veneering porcelain was removed, and load was applied directly to the framework, there was a clear increase in stress concentration with a concave design on supporting implants and bone structure. Conclusions: The present study showed that the use of a concave design in the pontic frameworks of fixed partial dentures increases the von Mises stress levels on implant abutments and supporting bone structure. However, the veneering porcelain element reduces the effect of the framework and compensates for design weaknesses. PMID:20922156
Anaby, Dana; Lal, Shalini; Huszczynski, Justine; Maich, Jana; Rogers, Jade; Law, Mary
2014-11-01
Comparative effectiveness research (CER) strives for evidence to inform clinical decisions for specific clients in typical health care settings. While the randomized controlled trial (RCT) is well-aligned with the objectives of CER, this design may not be feasible or applicable to all research questions, particularly those pertaining to clinical decision making and individually based change. It is important, therefore, to consider alternative approaches, especially when studying complex and subjective outcomes such as children's participation. We propose the use of interrupted time series (ITS) quasi-experimental design for its potential application in determining the effectiveness of participation-focused interventions. In this perspective, ITS design is described, ascertaining its advantages and limitations, and suggestions are provided to overcome challenges to implementation. Results of a case study using the ITS approach to evaluate changes in participation of an adolescent with physical disabilities are described. Finally, strategies to implement this design in practice are suggested.
A Taguchi study of the aeroelastic tailoring design process
NASA Technical Reports Server (NTRS)
Bohlmann, Jonathan D.; Scott, Robert C.
1991-01-01
A Taguchi study was performed to determine the important players in the aeroelastic tailoring design process and to find the best composition of the optimization's objective function. The Wing Aeroelastic Synthesis Procedure (TSO) was used to ascertain the effects that factors such as composite laminate constraints, roll effectiveness constraints, and built-in wing twist and camber have on the optimum, aeroelastically tailored wing skin design. The results show the Taguchi method to be a viable engineering tool for computational inquiries, and provide some valuable lessons about the practice of aeroelastic tailoring.
NASA Astrophysics Data System (ADS)
Kelani, Razacki Raphael E. D.
This study has two purposes. The practical purpose of the study was to provide Benin middle school science teachers with an effective technology education professional development (TEPD) program which granted teachers with content knowledge in technology education (TE), PCK in TE, design hands-on models in TE, and design rubrics assessing students' works. The research purpose of the study was to explore teachers' TE content knowledge and PCK, changes in teachers' self-efficacy beliefs in teaching the TE portion of the curriculum, and teachers' perceptions of their TEPD experience after participating in the program. Four sessions of the TEPD program were carried out with two groups of teachers (N = 23 & 28). A mixed methods research design was utilized to collect data. Pre-experimental one-group pretest-posttest research design was used to collect quantitative data. Two instruments, the technology education teacher self-efficacy beliefs instrument (TETEBI) and the TE Awareness instrument, were designed. The qualitative research design employed a case study with participating teachers' after-session journals and after-session evaluation, classroom observations, teachers' and students' interviews. Overall results of the study revealed that the TEPD program impacted positively participating teachers. Salient results indicated that (1) the TEPD program was effective; (2) although quantitative analysis was inconclusive, through documents analysis, teachers' self-efficacy beliefs were enhanced after participating in the program; (3) teachers did acquire TE content knowledge and PCK; (4) teachers were effectively teaching the TE lessons integrated in the science curriculum; and (5) teachers expressed positive perceptions about the program and acknowledged its soundness, relevancy and effectiveness. Other characteristics of effective PD have been founded such as trainers' expertise and consideration of cultural and contextual issues of the trainees. Interpretations of the results led to ten educational implications that could improve TE teaching in secondary school settings in Benin, as well as in other developing countries with similar features. Finally, five recommendations were made for further investigations.
Berger, Marc L; Dreyer, Nancy; Anderson, Fred; Towse, Adrian; Sedrakyan, Art; Normand, Sharon-Lise
2012-01-01
In both the United States and Europe there has been an increased interest in using comparative effectiveness research of interventions to inform health policy decisions. Prospective observational studies will undoubtedly be conducted with increased frequency to assess the comparative effectiveness of different treatments, including as a tool for "coverage with evidence development," "risk-sharing contracting," or key element in a "learning health-care system." The principle alternatives for comparative effectiveness research include retrospective observational studies, prospective observational studies, randomized clinical trials, and naturalistic ("pragmatic") randomized clinical trials. This report details the recommendations of a Good Research Practice Task Force on Prospective Observational Studies for comparative effectiveness research. Key issues discussed include how to decide when to do a prospective observational study in light of its advantages and disadvantages with respect to alternatives, and the report summarizes the challenges and approaches to the appropriate design, analysis, and execution of prospective observational studies to make them most valuable and relevant to health-care decision makers. The task force emphasizes the need for precision and clarity in specifying the key policy questions to be addressed and that studies should be designed with a goal of drawing causal inferences whenever possible. If a study is being performed to support a policy decision, then it should be designed as hypothesis testing-this requires drafting a protocol as if subjects were to be randomized and that investigators clearly state the purpose or main hypotheses, define the treatment groups and outcomes, identify all measured and unmeasured confounders, and specify the primary analyses and required sample size. Separate from analytic and statistical approaches, study design choices may strengthen the ability to address potential biases and confounding in prospective observational studies. The use of inception cohorts, new user designs, multiple comparator groups, matching designs, and assessment of outcomes thought not to be impacted by the therapies being compared are several strategies that should be given strong consideration recognizing that there may be feasibility constraints. The reasoning behind all study design and analytic choices should be transparent and explained in study protocol. Execution of prospective observational studies is as important as their design and analysis in ensuring that results are valuable and relevant, especially capturing the target population of interest, having reasonably complete and nondifferential follow-up. Similar to the concept of the importance of declaring a prespecified hypothesis, we believe that the credibility of many prospective observational studies would be enhanced by their registration on appropriate publicly accessible sites (e.g., clinicaltrials.gov and encepp.eu) in advance of their execution. Copyright © 2012 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.
Leveraging contact network structure in the design of cluster randomized trials.
Harling, Guy; Wang, Rui; Onnela, Jukka-Pekka; De Gruttola, Victor
2017-02-01
In settings like the Ebola epidemic, where proof-of-principle trials have provided evidence of efficacy but questions remain about the effectiveness of different possible modes of implementation, it may be useful to conduct trials that not only generate information about intervention effects but also themselves provide public health benefit. Cluster randomized trials are of particular value for infectious disease prevention research by virtue of their ability to capture both direct and indirect effects of intervention, the latter of which depends heavily on the nature of contact networks within and across clusters. By leveraging information about these networks-in particular the degree of connection across randomized units, which can be obtained at study baseline-we propose a novel class of connectivity-informed cluster trial designs that aim both to improve public health impact (speed of epidemic control) and to preserve the ability to detect intervention effects. We several designs for cluster randomized trials with staggered enrollment, in each of which the order of enrollment is based on the total number of ties (contacts) from individuals within a cluster to individuals in other clusters. Our designs can accommodate connectivity based either on the total number of external connections at baseline or on connections only to areas yet to receive the intervention. We further consider a "holdback" version of the designs in which control clusters are held back from re-randomization for some time interval. We investigate the performance of these designs in terms of epidemic control outcomes (time to end of epidemic and cumulative incidence) and power to detect intervention effect, by simulating vaccination trials during an SEIR-type epidemic outbreak using a network-structured agent-based model. We compare results to those of a traditional Stepped Wedge trial. In our simulation studies, connectivity-informed designs lead to a 20% reduction in cumulative incidence compared to comparable traditional study designs, but have little impact on epidemic length. Power to detect intervention effect is reduced in all connectivity-informed designs, but "holdback" versions provide power that is very close to that of a traditional Stepped Wedge approach. Incorporating information about cluster connectivity in the design of cluster randomized trials can increase their public health impact, especially in acute outbreak settings. Using this information helps control outbreaks-by minimizing the number of cross-cluster infections-with very modest cost in terms of power to detect effectiveness.
NASA Technical Reports Server (NTRS)
Pan, C. H. T.; Malanoski, S. B.
1972-01-01
A preliminary design study was performed to seek a fluid-film thrust bearing design intended to be part of a high-speed, hybrid (rolling element/fluid film) bearing configuration. The base line used is a design previously tested. To improve the accuracy of theoretical predictions of load capacity, flow rate, and friction power loss, an analytical procedure was developed to include curvature effects inherent in thrust bearings and to allow for the temperature rise in the fluid due to viscous heating. Also, a narrow-groove approximation in the treatment of the temperature field was formulated to apply the procedure to the Whipple thrust bearing. A comparative trade-off study was carried out assuming isothermal films; its results showed the shrouded-step design to be superior to the Whipple design for the intended application. An extensive parametric study was performed, employing isoviscous calculations, to determine the optimized design, which was subsequently recalculated allowing for temperature effects.
Designing Antibacterial Peptides with Enhanced Killing Kinetics
Waghu, Faiza H.; Joseph, Shaini; Ghawali, Sanket; Martis, Elvis A.; Madan, Taruna; Venkatesh, Kareenhalli V.; Idicula-Thomas, Susan
2018-01-01
Antimicrobial peptides (AMPs) are gaining attention as substitutes for antibiotics in order to combat the risk posed by multi-drug resistant pathogens. Several research groups are engaged in design of potent anti-infective agents using natural AMPs as templates. In this study, a library of peptides with high sequence similarity to Myeloid Antimicrobial Peptide (MAP) family were screened using popular online prediction algorithms. These peptide variants were designed in a manner to retain the conserved residues within the MAP family. The prediction algorithms were found to effectively classify peptides based on their antimicrobial nature. In order to improve the activity of the identified peptides, molecular dynamics (MD) simulations, using bilayer and micellar systems could be used to design and predict effect of residue substitution on membranes of microbial and mammalian cells. The inference from MD simulation studies well corroborated with the wet-lab observations indicating that MD-guided rational design could lead to discovery of potent AMPs. The effect of the residue substitution on membrane activity was studied in greater detail using killing kinetic analysis. Killing kinetics studies on Gram-positive, negative and human erythrocytes indicated that a single residue change has a drastic effect on the potency of AMPs. An interesting outcome was a switch from monophasic to biphasic death rate constant of Staphylococcus aureus due to a single residue mutation in the peptide. PMID:29527201
ERIC Educational Resources Information Center
Gyasi, Richard Sarfo; Xi, Wang Bao; Owusu-Ampomah, Yvonne
2016-01-01
The purpose of this study was to explore the effect of leadership styles on academic performance in Junior High Schools (JHS) in Asonomaso Nkwanta in the Kwabre District Assembly of Ashanti Region in Ghana. The design for the study was a mixed study using both the qualitative and quantitative analyzes. It was a correlation survey designed to…
ERIC Educational Resources Information Center
Korkmaz, Özgen
2016-01-01
The aim of the study was to present the effect of Lego Mindstorms Ev3 based design activities on students' attitudes towards learning computer programming, self-efficacy beliefs and levels of academic achievement. The research is a pretest-posttest with control group semi-experimental study. The study group of the research consisted of 53 students…
ERIC Educational Resources Information Center
Paskvan, Brian A.
2011-01-01
The purpose of this case study was to explore the influence of four factors--politics, economics, society, and technology--on educational delivery strategies, space needs, and design at Owens Community College. The future effects of these factors on the college were predicted four to six years from the time the study was conducted. The researcher…
The Effect of School Design on Student Performance
ERIC Educational Resources Information Center
Ariani, Mohsen Ghasemi; Mirdad, Fatemeh
2016-01-01
The present study aims at exploring the influence of school design on student performance. The participants consisted of 150 students who studied at two Iranian public school and private school in Mashhad City. School Design and Planning Laboratory (SDPL) model of Georgia University (and Tanner (2009)) was used as an appraisal indicator of school…
Pasadena City College SIGI Project Research Design. Pilot Study.
ERIC Educational Resources Information Center
Risser, John J.; Tulley, John E.
A pilot study evaluation of SIGI (System of Interactive Guidance and Information) at Pasadena City College in 1974-75 tested the effectiveness of an experimental research design for an expanded field test of the system the following year. (SIGI is a computer based career guidance program designed by Educational Testing Service to assist community…
Examining the Impact of Adaptively Faded Worked Examples on Student Learning Outcomes
ERIC Educational Resources Information Center
Flores, Raymond; Inan, Fethi
2014-01-01
The purpose of this study was to explore effective ways to design guided practices within a web-based mathematics problem solving tutorial. Specifically, this study examined student learning outcome differences between two support designs (e.g. adaptively faded and fixed). In the adaptively faded design, students were presented with problems in…
Group-Based Life Design Counseling in an Italian Context
ERIC Educational Resources Information Center
Di Fabio, Annamaria; Maree, Jacobus Gideon
2012-01-01
This study examined the effectiveness of group-based Life Design Counseling using the Career-Story Interview. Written exercises were used to implement the seven topics in the Career-Story Interview. The present study employed an experimental design that involved two groups of Italian entrepreneurs from the agricultural and trade sectors, namely an…
Hakama, Matti; Moss, Sue M; Stenman, Ulf-Hakan; Roobol, Monique J; Zappa, Marco; Carlsson, Sigrid; Randazzo, Marco; Nelen, Vera; Hugosson, Jonas
2017-06-01
Objectives To calculate design-corrected estimates of the effect of screening on prostate cancer mortality by centre in the European Randomised Study of Screening for Prostate Cancer (ERSPC). Setting The ERSPC has shown a 21% reduction in prostate cancer mortality in men invited to screening with follow-up truncated at 13 years. Centres either used pre-consent randomisation (effectiveness design) or post-consent randomisation (efficacy design). Methods In six centres (three effectiveness design, three efficacy design) with follow-up until the end of 2010, or maximum 13 years, the effect of screening was estimated as both effectiveness (mortality reduction in the target population) and efficacy (reduction in those actually screened). Results The overall crude prostate cancer mortality risk ratio in the intervention arm vs control arm for the six centres was 0.79 ranging from a 14% increase to a 38% reduction. The risk ratio was 0.85 in centres with effectiveness design and 0.73 in those with efficacy design. After correcting for design, overall efficacy was 27%, 24% in pre-consent and 29% in post-consent centres, ranging between a 12% increase and a 52% reduction. Conclusion The estimated overall effect of screening in attenders (efficacy) was a 27% reduction in prostate cancer mortality at 13 years' follow-up. The variation in efficacy between centres was greater than the range in risk ratio without correction for design. The centre-specific variation in the mortality reduction could not be accounted for by the randomisation method.
Effect of mold designs on molten metal behaviour in high-pressure die casting
NASA Astrophysics Data System (ADS)
Ibrahim, M. D.; Rahman, M. R. A.; Khan, A. A.; Mohamad, M. R.; Suffian, M. S. Z. M.; Yunos, Y. S.; Wong, L. K.; Mohtar, M. Z.
2017-04-01
This paper presents a research study conducted in a local automotive component manufacturer that produces aluminium alloy steering housing local and global markets. This study is to investigate the effect of design modification of mold in die casting as to improve the production rate. Design modification is carried out on the casting shot of the mold. Computer flow simulation was carried out to study the flow of molten metal in the mold with respect to the mold design modification. The design parameters of injection speed, die temperature and clamping force has been included in the study. The result of the simulation showed that modifications of casting shot give significant impact towards the molten flow behaviour in casting process. The capabilities and limitations of die casting process simulation to conduct defect analysis had been optimized. This research will enhance the efficiency of the mass production of the industry of die casting with the understanding of defect analysis, which lies on the modification of the mold design, a way early in its stages of production.
IEA Wind TCP Task 26: Impacts of Wind Turbine Technology on the System Value of Wind in Europe
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lantz, Eric J.; Riva, Alberto D.; Hethey, Janos
This report analyzes the impact of different land-based wind turbine designs on grid integration and related system value and cost. This topic has been studied in a number of previous publications, showing the potential benefits of wind turbine technologies that feature higher capacity factors. Building on the existing literature, this study aims to quantify the effects of different land-based wind turbine designs in the context of a projection of the European power system to 2030. This study contributes with insights on the quantitative effects in a likely European market setup, taking into account the effect of existing infrastructure on bothmore » existing conventional and renewable generation capacities. Furthermore, the market effects are put into perspective by comparing cost estimates for deploying different types of turbine design. Although the study focuses on Europe, similar considerations and results can be applied to other power systems with high wind penetration.« less
Testing effects in mixed- versus pure-list designs.
Rowland, Christopher A; Littrell-Baez, Megan K; Sensenig, Amanda E; DeLosh, Edward L
2014-08-01
In the present study, we investigated the role of list composition in the testing effect. Across three experiments, participants learned items through study and initial testing or study and restudy. List composition was manipulated, such that tested and restudied items appeared either intermixed in the same lists (mixed lists) or in separate lists (pure lists). In Experiment 1, half of the participants received mixed lists and half received pure lists. In Experiment 2, all participants were given both mixed and pure lists. Experiment 3 followed Erlebacher's (Psychological Bulletin, 84, 212-219, 1977) method, such that mixed lists, pure tested lists, and pure restudied lists were given to independent groups. Across all three experiments, the final recall results revealed significant testing effects for both mixed and pure lists, with no reliable difference in the magnitude of the testing advantage across list designs. This finding suggests that the testing effect is not subject to a key boundary condition-list design-that impacts other memory phenomena, including the generation effect.
Columbus safety and reliability
NASA Astrophysics Data System (ADS)
Longhurst, F.; Wessels, H.
1988-10-01
Analyses carried out to ensure Columbus reliability, availability, and maintainability, and operational and design safety are summarized. Failure modes/effects/criticality is the main qualitative tool used. The main aspects studied are fault tolerance, hazard consequence control, risk minimization, human error effects, restorability, and safe-life design.
Composite reinforced propellant tanks. [space shuttles
NASA Technical Reports Server (NTRS)
Brown, L. D.; Martin, M. J.; Aleck, B. J.; Landes, R.
1975-01-01
Design studies involving weight and cost were carried out for several structural concepts applicable to space shuttle disposable tankage. An effective design, a honeycomb stabilized pressure vessel, was chosen. A test model was designed and fabricated.
Attitudinal Responses to Changes in Noise Exposure in Residential Communities
NASA Technical Reports Server (NTRS)
Horonjeff, Richard D.; Robert, William E.
1997-01-01
The purpose of this study is (1) to investigate the current body of knowledge encompassing two related topics: (a) to what extent can we reliably predict the change in people's attitudes in response to an abrupt change in noise exposure, and (b) after the change, is there a decay in the abrupt-change effect whereby people's attitudes slowly shift from their initial reaction to a steady-state value? and (2) to provide recommendations for any future work that may be needed. The literature search located 23 studies relating to one or both of the above topics. These prior studies shed considerable light on the current ability to predict initial reaction and decay effects. The literature makes one point very clear: Great care in both experimental design and data analysis is necessary to produce credible, convincing findings, both in the reanalysis of existing data and for planning future data acquisition and analysis studies. New airport studies must be designed to minimize nuisance variables and avoid past design features that may have introduced sufficient unexplained variance to mask sought after effects. Additionally, the study must be designed to tie in with previous investigations by incorporating similar survey questions and techniques.
Hallingberg, Britt; Turley, Ruth; Segrott, Jeremy; Wight, Daniel; Craig, Peter; Moore, Laurence; Murphy, Simon; Robling, Michael; Simpson, Sharon Anne; Moore, Graham
2018-01-01
Evaluations of complex interventions in public health are frequently undermined by problems that can be identified before the effectiveness study stage. Exploratory studies, often termed pilot and feasibility studies, are a key step in assessing the feasibility and value of progressing to an effectiveness study. Such studies can provide vital information to support more robust evaluations, thereby reducing costs and minimising potential harms of the intervention. This systematic review forms the first phase of a wider project to address the need for stand-alone guidance for public health researchers on designing and conducting exploratory studies. The review objectives were to identify and examine existing recommendations concerning when such studies should be undertaken, questions they should answer, suitable methods, criteria for deciding whether to progress to an effectiveness study and appropriate reporting. We searched for published and unpublished guidance reported between January 2000 and November 2016 via bibliographic databases, websites, citation tracking and expert recommendations. Included papers were thematically synthesized. The search retrieved 4095 unique records. Thirty papers were included, representing 25 unique sources of guidance/recommendations. Eight themes were identified: pre-requisites for conducting an exploratory study, nomenclature, guidance for intervention assessment, guidance surrounding any future evaluation study design, flexible versus fixed design, progression criteria to a future evaluation study, stakeholder involvement and reporting of exploratory studies. Exploratory studies were described as being concerned with the intervention content, the future evaluation design or both. However, the nomenclature and endorsed methods underpinning these aims were inconsistent across papers. There was little guidance on what should precede or follow an exploratory study and decision-making surrounding this. Existing recommendations are inconsistent concerning the aims, designs and conduct of exploratory studies, and guidance is lacking on the evidence needed to inform when to proceed to an effectiveness study. PROSPERO 2016, CRD42016047843.
ERIC Educational Resources Information Center
Jack, Gladys Uzezi
2017-01-01
This study investigated the effect of learning cycle constructivist-based approach on secondary schools students' academic achievement and their attitude towards chemistry. The design used was a pre-test, post-test non randomized control group quasi experimental research design. The design consisted of two instructional groups (learning cycle…
ERIC Educational Resources Information Center
Andrade, Jeanette; Huang, Wen-Hao David; Bohn, Dawn M.
2015-01-01
The effective design of course materials is critical for student learning, especially for large lecture introductory courses. This quantitative study was designed to explore the effect multimedia and content difficulty has on students' cognitive load and learning outcomes. College students (n = 268) were randomized into 1 of 3 multimedia groups:…
ERIC Educational Resources Information Center
Hansen, Michele J.; Meshulam, Susan; Parker, Brooke
2013-01-01
National attention is focused on the persistent high failure rates for students enrolled in math courses, and the search for strategies to change these outcomes is on. This study used a mixed-method research design to assess the effectiveness of a learning community course designed to improve the math performance levels of firstyear students.…
ERIC Educational Resources Information Center
Wu, Qun; Wang, Yecheng
2015-01-01
The purpose of this study is to identify the occurrence of Sudden Moments of Inspiration (SMI) in the sketching process of industrial design through experiments to explain the effect of sub consciousness on SMI. There are a pre-experiment and a formal experiment. In the formal experiment, nine undergraduates majoring in industrial design with same…
Factor levels for density comparisons in the split-block spacing design
Kurt H. Riitters; Brian J. Stanton; Robbert H. Walkup
1989-01-01
The split-block spacing design is a compact test of the effects of within-row and between-row spacings. But the sometimes awkward analysis of density (i.e., trees/ha) effects may deter use of the design. The analysis is simpler if the row spacings are chosen to obtain a balanced set of equally spaced density and rectangularity treatments. A spacing study in poplar (...
ERIC Educational Resources Information Center
Ashworth, Kristen E.
2012-01-01
The purposes of this study were to determine the effectiveness of a vocabulary intervention for first-grade students at risk for reading and language difficulties and to compare the results of a regression discontinuity design to those of an experimental design. The specific research questions were: (1) Do first-graders who are at risk of reading…
Michiels, Bart; Heyvaert, Mieke; Onghena, Patrick
2018-04-01
The conditional power (CP) of the randomization test (RT) was investigated in a simulation study in which three different single-case effect size (ES) measures were used as the test statistics: the mean difference (MD), the percentage of nonoverlapping data (PND), and the nonoverlap of all pairs (NAP). Furthermore, we studied the effect of the experimental design on the RT's CP for three different single-case designs with rapid treatment alternation: the completely randomized design (CRD), the randomized block design (RBD), and the restricted randomized alternation design (RRAD). As a third goal, we evaluated the CP of the RT for three types of simulated data: data generated from a standard normal distribution, data generated from a uniform distribution, and data generated from a first-order autoregressive Gaussian process. The results showed that the MD and NAP perform very similarly in terms of CP, whereas the PND performs substantially worse. Furthermore, the RRAD yielded marginally higher power in the RT, followed by the CRD and then the RBD. Finally, the power of the RT was almost unaffected by the type of the simulated data. On the basis of the results of the simulation study, we recommend at least 20 measurement occasions for single-case designs with a randomized treatment order that are to be evaluated with an RT using a 5% significance level. Furthermore, we do not recommend use of the PND, because of its low power in the RT.
Weimer, Katja; Enck, Paul
2014-01-01
Many study designs and design variants have been developed in the past to either overcome or enhance drug-placebo differences in clinical trials or to identify and characterize placebo responders in experimental studies. They share many commonalities as well as differences that are discussed here: the role of deception and ethical restrictions, habituation effects and the control of the natural course of disease, assay sensitivity testing and effective blinding, acceptability and motivation of patients and volunteers, and the development of individualized medicine. These are fostered by two opposite strategies: utilizing the beneficial aspects of the placebo response-and avoiding its negative counterpart, the nocebo effect-in medical routine for the benefit of patients, and minimizing-by controlling-the negative aspects of the placebo effect during drug development.
Developing Canadian physician: the quest for leadership effectiveness.
Comber, Scott; Wilson, Lisette; Crawford, Kyle C
2016-07-04
Purpose The purpose of this study is to discern the physicians' perception of leadership effectiveness in their clinical and non-clinical roles (leadership) by identifying their political skill levels. Design/methodology/approach A sample of 209 Canadian physicians was surveyed using the Political Skills Inventory (PSI) during the period 2012-2014. The PSI was chosen because it assesses leadership effectiveness on four dimensions: social astuteness, interpersonal influence, networking ability and apparent authenticity. Findings Physicians in clinical roles' PSI scores were significantly lower in all four PSI dimensions when compared to all other physicians in non-clinical roles, with the principal difference being in their networking abilities. Practical implications More emphasis is needed on educating and training physicians, specifically in the areas of political skills, in current clinical roles if they are to assume leadership roles and be effective. Originality/value Although this study is located in Canada, the study design and associated findings may have implications to other areas and countries wanting to increase physician leadership effectiveness. Further, replication of this study in other settings may provide insight into the future design of physician leadership training curriculum.
Rosander, Ulla; Rumpunen, Kimmo; Olsson, Viktoria; Åström, Mikael; Rosander, Pia; Wendin, Karin
2017-01-01
ABSTRACT Berries contain bioactive compounds that may affect children’s cognitive function positively, while hunger and thirst during lessons before lunch affect academic performance negatively. This pilot study addresses methodological challenges in studying if a berry smoothie, offered to schoolchildren as a mid-morning beverage, affects academic performance. The objective was to investigate if a cross-over design can be used to study these effects in a school setting. Therefore, in order to investigate assay sensitivity, 236 Swedish children aged 10–12 years were administered either a berry smoothie (active) or a fruit-based control beverage after their mid-morning break. Both beverages provided 5% of child daily energy intake. In total, 91% of participants completed the study. Academic performance was assessed using the d2 test of attention. Statistical analyses were performed using the Wilcoxon signed rank test in StatXact v 10.3. The results showed that the children consumed less of the active berry smoothie than the control (154 g vs. 246 g). Both beverages increased attention span and concentration significantly (p = 0.000). However, as there was no significant difference (p = 0.938) in the magnitude of this effect between the active and control beverages, the assay sensitivity of the study design was not proven. The effect of the beverages on academic performance was attributed the supplementation of water and energy. Despite careful design, the active smoothie was less accepted than the control. This could be explained by un-familiar sensory characteristics and peer influence, stressing the importance of sensory similarity and challenges to perform a study in school settings. The employed cross-over design did not reveal any effects of bioactive compound consumption on academic performance. In future studies, the experimental set up should be modified or replaced by e.g. the parallel study design, in order to provide conclusive results. PMID:29230155
Rosander, Ulla; Rumpunen, Kimmo; Olsson, Viktoria; Åström, Mikael; Rosander, Pia; Wendin, Karin
2017-01-01
Berries contain bioactive compounds that may affect children's cognitive function positively, while hunger and thirst during lessons before lunch affect academic performance negatively. This pilot study addresses methodological challenges in studying if a berry smoothie, offered to schoolchildren as a mid-morning beverage, affects academic performance. The objective was to investigate if a cross-over design can be used to study these effects in a school setting. Therefore, in order to investigate assay sensitivity, 236 Swedish children aged 10-12 years were administered either a berry smoothie (active) or a fruit-based control beverage after their mid-morning break. Both beverages provided 5% of child daily energy intake. In total, 91% of participants completed the study. Academic performance was assessed using the d2 test of attention. Statistical analyses were performed using the Wilcoxon signed rank test in StatXact v 10.3. The results showed that the children consumed less of the active berry smoothie than the control (154 g vs. 246 g). Both beverages increased attention span and concentration significantly (p = 0.000). However, as there was no significant difference (p = 0.938) in the magnitude of this effect between the active and control beverages, the assay sensitivity of the study design was not proven. The effect of the beverages on academic performance was attributed the supplementation of water and energy. Despite careful design, the active smoothie was less accepted than the control. This could be explained by un-familiar sensory characteristics and peer influence, stressing the importance of sensory similarity and challenges to perform a study in school settings. The employed cross-over design did not reveal any effects of bioactive compound consumption on academic performance. In future studies, the experimental set up should be modified or replaced by e.g. the parallel study design, in order to provide conclusive results.
NASA Technical Reports Server (NTRS)
Blumenthal, Rob; Kim, Dongmoon; Bache, George
1992-01-01
The hydrogen mixer for the Space Transportation Main Engine is used to mix cold hydrogen bypass flow with warm hydrogen coolant chamber gas, which is then fed to the injectors. It is very important to have a uniform fuel temperature at the injectors in order to minimize mixture ratio problems due to the fuel density variations. In addition, the fuel at the injector has certain total pressure requirements. In order to achieve these objectives, the hydrogen mixer must provide a thoroughly mixed fluid with a minimum pressure loss. The AEROVISC computational fluid dynamics (CFD) code was used to analyze the STME hydrogen mixer, and proved to be an effective tool in optimizing the mixer design. AEROVISC, which solves the Reynolds Stress-Averaged Navier-Stokes equations in primitive variable form, was used to assess the effectiveness of different mixer designs. Through a parametric study of mixer design variables, an optimal design was selected which minimized mixed fuel temperature variation and fuel mixer pressure loss. The use of CFD in the design process of the STME hydrogen mixer was effective in achieving an optimal mixer design while reducing the amount of hardware testing.
ANALYSIS OF DESIGN RANGE FOR A STROKING SEAT ON A STROKING FLOOR TO MITIGATE BLAST LOADING EFFECTS
2017-05-16
and the optimal design points that can mitigate the occupant injury to a range of input parameters. One key conclusion from the study is that blast...stroking) in another case . The results from this study are shown in Figure 10. The original two baseline design points explored in the previous...this study , occupant is positioned with feet on the foot-rest attached to the seat system. However, a particular vehicle design may have the
Comparative effectiveness research in cancer with observational data.
Giordano, Sharon H
2015-01-01
Observational studies are increasingly being used for comparative effectiveness research. These studies can have the greatest impact when randomized trials are not feasible or when randomized studies have not included the population or outcomes of interest. However, careful attention must be paid to study design to minimize the likelihood of selection biases. Analytic techniques, such as multivariable regression modeling, propensity score analysis, and instrumental variable analysis, also can also be used to help address confounding. Oncology has many existing large and clinically rich observational databases that can be used for comparative effectiveness research. With careful study design, observational studies can produce valid results to assess the benefits and harms of a treatment or intervention in representative real-world populations.
The Effects of Diversity Training on Specific and General Attitudes toward Diversity
ERIC Educational Resources Information Center
Schmidtke, James M.; Badhesha, Raj Singh; Moore, Scott D.
2008-01-01
Purpose: This paper aims to examine the effects of watching a video providing knowledge about either a Sikh student or an older student on participants' knowledge about each particular group, their attitudes towards that group. Design/methodology/approach: The study used a pre-post experimental design and examined the effects of diversity…
Assessing the Generalizability of Estimates of Causal Effects from Regression Discontinuity Designs
ERIC Educational Resources Information Center
Bloom, Howard S.; Porter, Kristin E.
2012-01-01
In recent years, the regression discontinuity design (RDD) has gained widespread recognition as a quasi-experimental method that when used correctly, can produce internally valid estimates of causal effects of a treatment, a program or an intervention (hereafter referred to as treatment effects). In an RDD study, subjects or groups of subjects…
ERIC Educational Resources Information Center
Perry, Valerie; Albeg, Loren; Tung, Catherine
2012-01-01
The current study examined the effects of self-regulatory interventions on reading, writing, and math by conducting a meta-analysis of single-case design research. Self-regulatory interventions have promise as an effective approach that is both minimally invasive and involves minimal resources. Effects of the interventions were analyzed by…
Sample size calculations for stepped wedge and cluster randomised trials: a unified approach
Hemming, Karla; Taljaard, Monica
2016-01-01
Objectives To clarify and illustrate sample size calculations for the cross-sectional stepped wedge cluster randomized trial (SW-CRT) and to present a simple approach for comparing the efficiencies of competing designs within a unified framework. Study Design and Setting We summarize design effects for the SW-CRT, the parallel cluster randomized trial (CRT), and the parallel cluster randomized trial with before and after observations (CRT-BA), assuming cross-sectional samples are selected over time. We present new formulas that enable trialists to determine the required cluster size for a given number of clusters. We illustrate by example how to implement the presented design effects and give practical guidance on the design of stepped wedge studies. Results For a fixed total cluster size, the choice of study design that provides the greatest power depends on the intracluster correlation coefficient (ICC) and the cluster size. When the ICC is small, the CRT tends to be more efficient; when the ICC is large, the SW-CRT tends to be more efficient and can serve as an alternative design when the CRT is an infeasible design. Conclusion Our unified approach allows trialists to easily compare the efficiencies of three competing designs to inform the decision about the most efficient design in a given scenario. PMID:26344808
Design Study for a Free-piston Vuilleumier Cycle Heat Pump
NASA Astrophysics Data System (ADS)
Matsue, Junji; Hoshino, Norimasa; Ikumi, Yonezou; Shirai, Hiroyuki
Conceptual design for a free-piston Vuilleumier cycle heat pump machine was proposed. The machine was designed based upon the numerical results of a dynamic analysis method. The method included the effect of self excitation vibration with dissipation caused by the flow friction of an oscillating working gas flow and solid friction of seals. It was found that the design values of reciprocating masses and spring constants proposed in published papers related to this study were suitable for practical use. The fundamental effects of heat exchanger elements on dynamic behaviors of the machine were clarified. It has been pointed out that some improvements were required for thermodynamic analysis of heat exchangers and working spaces.
Methodologic ramifications of paying attention to sex and gender differences in clinical research.
Prins, Martin H; Smits, Kim M; Smits, Luc J
2007-01-01
Methodologic standards for studies on sex and gender differences should be developed to improve reporting of studies and facilitate their inclusion in systematic reviews. The essence of these studies lies within the concept of effect modification. This article reviews important methodologic issues in the design and reporting of pharmacogenetic studies. Differences in effect based on sex or gender should preferably be expressed in absolute terms (risk differences) to facilitate clinical decisions on treatment. Information on the distribution of potential effect modifiers or prognostic factors should be available to prevent a biased comparison of differences in effect between genotypes. Other considerations included the possibility of selective nonavailability of biomaterial and the choice of a statistical model to study effect modification. To ensure high study quality, additional methodologic issues should be taken into account when designing and reporting studies on sex and gender differences.
Accelerated longitudinal designs: An overview of modelling, power, costs and handling missing data.
Galbraith, Sally; Bowden, Jack; Mander, Adrian
2017-02-01
Longitudinal studies are often used to investigate age-related developmental change. Whereas a single cohort design takes a group of individuals at the same initial age and follows them over time, an accelerated longitudinal design takes multiple single cohorts, each one starting at a different age. The main advantage of an accelerated longitudinal design is its ability to span the age range of interest in a shorter period of time than would be possible with a single cohort longitudinal design. This paper considers design issues for accelerated longitudinal studies. A linear mixed effect model is considered to describe the responses over age with random effects for intercept and slope parameters. Random and fixed cohort effects are used to cope with the potential bias accelerated longitudinal designs have due to multiple cohorts. The impact of other factors such as costs and the impact of dropouts on the power of testing or the precision of estimating parameters are examined. As duration-related costs increase relative to recruitment costs the best designs shift towards shorter duration and eventually cross-sectional design being best. For designs with the same duration but differing interval between measurements, we found there was a cutoff point for measurement costs relative to recruitment costs relating to frequency of measurements. Under our model of 30% dropout there was a maximum power loss of 7%.
Goodman, Michael; Dana Flanders, W
2007-04-01
We compare methodological approaches for evaluating gene-environment interaction using a planned study of pediatric leukemia as a practical example. We considered three design options: a full case-control study (Option I), a case-only study (Option II), and a partial case-control study (Option III), in which information on controls is limited to environmental exposure only. For each design option we determined its ability to measure the main effects of environmental factor E and genetic factor G, and the interaction between E and G. Using the leukemia study example, we calculated sample sizes required to detect and odds ratio (OR) of 2.0 for E alone, an OR of 10 for G alone and an interaction G x E of 3. Option I allows measuring both main effects and interaction, but requires a total sample size of 1,500 cases and 1,500 controls. Option II allows measuring only interaction, but requires just 121 cases. Option III allows calculating the main effect of E, and interaction, but not the main effect of G, and requires a total of 156 cases and 133 controls. In this case, the partial case-control study (Option III) appears to be more efficient with respect to its ability to answer the research questions for the amount of resources required. The design options considered in this example are not limited to observational epidemiology and may be applicable in studies of pharmacogenomics, survivorship, and other areas of pediatric ALL research.
Alternative approaches to analytical designs in occupational injury epidemiology.
Mittleman, M A; Maldonado, G; Gerberich, S G; Smith, G S; Sorock, G S
1997-08-01
In this paper, we discuss the theoretical framework upon which observational studies of occupational injuries are based. Following a general description of how causal effects are estimated, the challenges faced by researchers working in this area are outlined, with an emphasis on case-control studies. These challenges include defining the at-risk period for workers whose tasks change over time and whose hazard period may be very brief, evaluating the underreporting of both exposures and injuries, and considering the effects of multiple injuries per individual on study design and data analysis. We review both the theoretical and practical considerations in the design and conduct of traditional case-control studies, based on the collection of individual level data, as well as other approaches, such as using information culled from administrative and descriptive databases, and case-control studies in which the plant or work site is the unit of analysis. The case-crossover design is also reviewed and its utility for reducing confounding due to differences between individuals by self-matching is highlighted. While this design has not yet been applied to the work setting, its potential for increasing our understanding of the causes of acute-onset occupational injuries seems promising. Finally, a variety of hybrid designs are discussed, including combinations of case-control, case-crossover, and cohort designs.
To Be or Not to Be in Thrall to the March of Smart Products
Van den Hende, Ellis A.
2016-01-01
ABSTRACT This article explores how perceived disempowerment impacts the intention to adopt smart autonomous products. Empirically, the paper builds on three studies to show this impact. Study 1 explores the relevance of the perceived disempowerment in respect of smart autonomous products. Study 2 manipulates autonomy of smart products and finds that perceived disempowerment mediates the link between smart products’ autonomy and adoption intention. Study 3 indicates that an intervention design―that is, a product design that allows consumers to intervene in the actions of an autonomous smart product―can reduce their perceived disempowerment in respect of autonomous smart products. Further, Study 3 reveals that personal innovativeness moderates the role that an intervention design plays in product adoption: an intervention design shows a positive effect on adoption intention for individuals with low personal innovativeness, but for those with high personal innovativeness no effect of an intervention design is present on adoption intention. The authors suggest that managers consider consumers’ perceived disempowerment when designing autonomous smart products, because (1) perceived disempowerment reduces adoption and (2) when targeted at consumers with low personal innovativeness, an intervention design reduces their perceived disempowerment. PMID:27980356
Zhai, Chun-Hui; Xuan, Jian-Bang; Fan, Hai-Liu; Zhao, Teng-Fei; Jiang, Jian-Lan
2018-05-03
In order to make a further optimization of process design via increasing the stability of design space, we brought in the model of Support Vector Regression (SVR). In this work, the extraction of podophyllotoxin was researched as a case study based on Quality by Design (QbD). We compared the fitting effect of SVR and the most used quadratic polynomial model (QPM) in QbD, and an analysis was made between the two design spaces obtained by SVR and QPM. As a result, the SVR stayed ahead of QPM in prediction accuracy, the stability of model and the generalization ability. The introduction of SVR into QbD made the extraction process of podophyllotoxin well designed and easier to control. The better fitting effect of SVR improved the application effect of QbD and the universal applicability of SVR, especially for non-linear, complicated and weak-regularity problems, widened the application field of QbD.
The Effects of Classic and Web-Designed Conceptual Change Texts on the Subject of Water Chemistry
ERIC Educational Resources Information Center
Tas, Erol; Gülen, Salih; Öner, Zeynep; Özyürek, Cengiz
2015-01-01
The purpose of this study is to research the effects of traditional and web-assisted conceptual change texts for the subject of water chemistry on the success, conceptual errors and permanent learning of students. A total of 37 8th graders in a secondary school of Samsun participated in this study which had a random experimental design with…
ERIC Educational Resources Information Center
Koç, Yakup
2017-01-01
The study aims to investigate the effect of "Physical Education and Sport Culture" (PESC) course on the attitudes of preservice classroom teachers towards physical education and sports. The one group pre-test post-test design among experimental models which is included in quantitative research designs was employed in the study. The study…
ERIC Educational Resources Information Center
Santagata, Rossella; Kersting, Nicole; Givvin, Karen B.; Stigler, James W.
2011-01-01
This study investigates, through an experimental design, the effectiveness of a professional development program on teacher knowledge and practices and on student learning. The program consisted of a series of video-based modules designed to respond to needs of U.S. teachers, as highlighted by findings from the 1999 Third International Mathematics…
ERIC Educational Resources Information Center
Mativo, John M.; Hill, Roger B.; Godfrey, Paul W.
2013-01-01
The focus of this study was to examine four characteristics for successful and unsuccessful students enrolled in basic mathematics courses at a technical college. The characteristics, considered to be in part effects of human factors in engineering and design, examined the preferred learning styles, computer information systems competency,…
ERIC Educational Resources Information Center
Varnell, Matt
2013-01-01
The purpose of this study was to evaluate the effect of rhythm and tonality on an academic memory task by comparing three different treatment conditions: a poem, a rhythmic chant (or rap), and a melodic rhythm (or song). A quasi-experimental experiment was designed and implemented, specifically a pretest-posttest-posttest control-group design.…
ERIC Educational Resources Information Center
Agboghoroma, Tim E.; Oyovwi, E. O.
2015-01-01
This study evaluated the effect of students' academic achievement on identified difficult concepts or topics in Senior Secondary School Biology in Delta State, Nigeria. The study was quasi-experimental and the design was a 2X2 factorial non-randomized pretest-posttest control group design. The sample was drawn from intact classes from four…
The Effects of Swedish Knife Model on Students' Understanding of the Digestive System
ERIC Educational Resources Information Center
Cerrah Ozsevgec, Lale; Artun, Huseyin; Unal, Melike
2012-01-01
This study was designed to examine the effect of Swedish Knife Model on students' understanding of digestive system. A simple experimental design (pretest-treatment-posttest) was used in the study and internal comparison of the results of the one group was made. The sample consisted of 40 7th grade Turkish students whose ages range from 13 to 15.…
ERIC Educational Resources Information Center
Melendez Alicea, Juan
1992-01-01
Presents steps taken in designing, justifying, and implementing an experimental study designed to investigate the effectiveness of distance education as a methodology for developing thinking skills. A discussion reviews major findings of the study by comparing student experiences from multimedia distance education and student experiences from…
A Literature Review: Website Design and User Engagement.
Garett, Renee; Chiu, Jason; Zhang, Ly; Young, Sean D
2016-07-01
Proper design has become a critical element needed to engage website and mobile application users. However, little research has been conducted to define the specific elements used in effective website and mobile application design. We attempt to review and consolidate research on effective design and to define a short list of elements frequently used in research. The design elements mentioned most frequently in the reviewed literature were navigation, graphical representation, organization, content utility, purpose, simplicity, and readability. We discuss how previous studies define and evaluate these seven elements. This review and the resulting short list of design elements may be used to help designers and researchers to operationalize best practices for facilitating and predicting user engagement.
Concurrent Design used in the Design of Space Instruments
NASA Technical Reports Server (NTRS)
Oxnevad, Knut I.
1998-01-01
At the Project Design Center at the Jet Propulsion Laboratory, a concurrent design environment is under development for supporting development and analyses of space instruments in the early, conceptual design phases. This environment is being utilized by a Team I, a multidisciplinary group of experts. Team I is providing study and proposal support. To provide the required support, the Team I concurrent design environment features effectively interconnected high-end optics, CAD, and thermal design and analysis tools. Innovative approaches for linking tools, and for transferring files between applications have been implemented. These approaches together with effective sharing of geometry between the optics, CAD, and thermal tools are already showing significant timesavings.
A Literature Review: Website Design and User Engagement
Garett, Renee; Chiu, Jason; Zhang, Ly; Young, Sean D.
2015-01-01
Proper design has become a critical element needed to engage website and mobile application users. However, little research has been conducted to define the specific elements used in effective website and mobile application design. We attempt to review and consolidate research on effective design and to define a short list of elements frequently used in research. The design elements mentioned most frequently in the reviewed literature were navigation, graphical representation, organization, content utility, purpose, simplicity, and readability. We discuss how previous studies define and evaluate these seven elements. This review and the resulting short list of design elements may be used to help designers and researchers to operationalize best practices for facilitating and predicting user engagement. PMID:27499833
NASA Technical Reports Server (NTRS)
Smith, Philip J.; Mccoy, C. Elaine; Layton, Charles; Orasanu, Judith; Chappel, Sherry; Palmer, EV; Corker, Kevin
1993-01-01
In a previous report, an empirical study of 30 pilots using the Flight Planning Testbed was reported. An identical experiment using the Flight Planning Testbed (FPT), except that 27 airline dispatchers were studied, is described. Five general questions were addressed in this study: (1) under what circumstances do the introduction of computer-generated suggestions (flight plans) influence the planning behavior of dispatchers (either in a beneficial or adverse manner); (2) what is the nature of such influences (i.e., how are the person's cognitive processes changed); (3) how beneficial are the general design concepts underlying FPT (use of a graphical interface, embedding graphics in a spreadsheet, etc.); (4) how effective are the specific implementation decisions made in realizing these general design concepts; and (5) how effectively do dispatchers evaluate situations requiring replanning, and how effectively do they identify appropriate solutions to these situations.
Low-cost point-focus solar concentrator, phase 1
NASA Technical Reports Server (NTRS)
Nelson, E. V.; Derbidge, T. C.; Erskine, D.; Maraschin, R. A.; Niemeyer, W. A.; Matsushita, M. J.; Overly, P. T.
1979-01-01
The results of the preliminary design study for the low cost point focus solar concentrator (LCPFSC) development program are presented. A summary description of the preliminary design is given. The design philosophy used to achieve a cost effective design for mass production is described. The concentrator meets all design requirements specified and is based on practical design solutions in every possible way.
Design study of Software-Implemented Fault-Tolerance (SIFT) computer
NASA Technical Reports Server (NTRS)
Wensley, J. H.; Goldberg, J.; Green, M. W.; Kutz, W. H.; Levitt, K. N.; Mills, M. E.; Shostak, R. E.; Whiting-Okeefe, P. M.; Zeidler, H. M.
1982-01-01
Software-implemented fault tolerant (SIFT) computer design for commercial aviation is reported. A SIFT design concept is addressed. Alternate strategies for physical implementation are considered. Hardware and software design correctness is addressed. System modeling and effectiveness evaluation are considered from a fault-tolerant point of view.
Design guide for space shuttle low-cost payloads
NASA Technical Reports Server (NTRS)
1971-01-01
A handbook is presented which delineates the principles of the new low-cost design methodology for designers of unmanned payloads to be carried by the space shuttle. The basic relationships between payload designs and program cost effects are discussed, and some concepts for designing low-cost payloads and implementing low-cost programs are given. The data are summarized from a payloads effects study of three unmanned earth satellites (OAO, a syneq orbiter, and a small research satellite), and the earth satellite design is emphasized. Brief summaries of space shuttle and space tug performance, environmental, and interface data pertinent to low-cost payload concepts are included.
DOT National Transportation Integrated Search
2008-05-01
This study was undertaken with the objective of assessing the current provisions in SDC-2006 for incorporating : vertical effects of ground motions in seismic evaluation and design of ordinary highway bridges. A : comprehensive series of simulations ...
Comparison of Instructors' and Students' Perceptions of the Effectiveness of Online Courses
ERIC Educational Resources Information Center
Seok, Soonhwa; DaCosta, Boaventura; Kinsell, Carolyn; Tung, Chan K.
2010-01-01
This study used an extensive online course evaluation inventory to analyze the subjects' perceptions of course effectiveness in the following subscales: flexibility, user interface, navigation, getting started, technical assistance, course management, universal design, communications, instructional design, and content. Survey results compared…
ERIC Educational Resources Information Center
Kuwik, Paul David
The purpose of the study was to determine whether exposing junior high school students to a unit on design in construction technology and to a unit on design in manufacturing technology significantly affects their achievement on a test measuring "Technological Principles of Design" when compared to a group of junior high school students exposed…
ARTS III/Parallel Processor Design Study
DOT National Transportation Integrated Search
1975-04-01
It was the purpose of this design study to investigate the feasibility, suitability, and cost-effectiveness of augmenting the ARTS III failsafe/failsoft multiprocessor system with a form of parallel processor to accomodate a large growth in air traff...
Investigating the effect of m-commerce design usability on customers' trust
NASA Astrophysics Data System (ADS)
Hussain, Azham Bin; Mahmood, Alaa Thamer; Naser, Raed Kamil
2017-10-01
User experience may vary from one user to another based on the design characteristics for processing a certain task. Our review of the literature revealed that there is a noticeable lack of studies on the effect of mobile or m-commerce design usability on customers' trust to perform certain activities. We investigated the effect of m-commerce design usability in terms of navigability, supportability, readability, creditability, and content relevant. A close-ended questionnaire was distributed to 20 customers who were asked to perform some tasks. The result showed that majority of the participants found m-commerce design usability to influence their trust of the app. The mentioned usability elements were found to positively influence customers' trust except for supportability. Our findings provide some insights to the m-commerce designers and developers and extend the current understanding about the potential of design usability in explaining users' usage behavior.
Bhattacharya, Debi; Aldus, Clare F; Barton, Garry; Bond, Christine M; Boonyaprapa, Sathon; Charles, Ian S; Fleetcroft, Robert; Holland, Richard; Jerosch-Herold, Christina; Salter, Charlotte; Shepstone, Lee; Walton, Christine; Watson, Steve; Wright, David J
2016-07-01
Medication organisation devices (MODs) provide compartments for a patient's medication to be organised into the days of the week and the recommended times the medication should be taken. To define the optimal trial design for testing the clinical effectiveness and cost-effectiveness of MODs. The feasibility study comprised a systematic review and focus groups to inform a randomised controlled trial (RCT) design. The resulting features were tested on a small scale, using a 2 × 2 factorial design to compare MODs with usual packaging and to compare weekly with monthly supply. The study design was then evaluated. Potential participants were identified by medical practices. Aged over 75 years, prescribed at least three solid oral dosage form medications, unintentionally non-adherent and self-medicating. Participants were excluded if deemed by their health-care team to be unsuitable. One of three MODs widely used in routine clinical practice supplied either weekly or monthly. To identify the most effective method of participant recruitment, to estimate the prevalence of intentional and unintentional non-adherence in an older population, to provide a point estimate of the effect size of MODs relative to usual care and to determine the feasibility and acceptability of trial participation. The systematic review included MOD studies of any design reporting medication adherence, health and social outcomes, resource utilisation or dispensing or administration errors. Focus groups with patients, carers and health-care professionals supplemented the systematic review to inform the RCT design. The resulting design was implemented and then evaluated through questionnaires and group discussions with participants and health-care professionals involved in trial delivery. Studies on MODs are largely of poor quality. The relationship between adherence and health outcomes is unclear. Of the limited studies reporting health outcomes, some reported a positive relationship while some reported increased hospitalisations associated with MODs. The pre-trial focus groups endorsed the planned study design, but suggested a minimum recruitment age of 50-60 years. A total of 35.4% of patients completing the baseline questionnaire were excluded because they already used a MOD. Active recruitment yielded a higher consent rate, but passive recruitment was more cost-effective. The prevalence of intentional non-adherence was 24.7% [n = 71, 95% confidence interval (CI) 19.7% to 29.6%] of participants. Of the remaining 76 participants, 46.1% (95% CI 34.8% to 57.3%) were unintentionally non-adherent. There was no indication of a difference in adherence between the study arms. Participants reported a high level of satisfaction with the design. Five adverse/serious adverse events were identified in the MOD study arms and none was identified in the control arms. There was no discernible difference in health economic outcomes between the four study arms; the mean intervention cost was £20 per month greater for MOD monthly relative to usual supply monthly. MOD provision to unintentionally non-adherent older people may cause medication-related adverse events. The primary outcome for a definitive MOD trial should be health outcomes. Such a trial should recruit patients by postal invitation and recruit younger patients. A study examining the association between MOD initiation and adverse effects is necessary and a strategy to safely introduce MODs should be explored. A definitive study testing the clinical effectiveness and cost-effectiveness of MODs is also required. Current Controlled Trials ISRCTN 30626972 and UKCRN 12739. This project was funded by National Institute for Health Research (NIHR) Health Technology Assessment Programme and will be published in full in Health Technology Assessment; Vol. 20, No. 50. See the NIHR Journals Library website for further project information.
Thinking outside ISD: A management model for instructional design
NASA Astrophysics Data System (ADS)
Taylor, Tony Dewayne
The purpose of this study was to examine the effectiveness of an instructional system management-level model proposed by the author designed to orchestrate the efficient development and implementation of customer requested curriculum. The three phases of systems-based model are designed to ensure delivery of high quality and timely instruction are: (1) the assessment and documentation of organizational training requirements; (2) project management control of curriculum development; and (3) the implementation of relevant instruction by competent instructors. This model also provides (4) measurable and quantifiable course evaluation results to justify return on investment and validate its importance with respect to the customer's organizational strategic objectives. The theoretical approach for this study was systems theory-based due to the nature of the instructional systems design model and the systematic design of the management model. The study was accomplished using single-case study application of qualitative style of inquiry as described by Patton (2002). Qualitative inquiry was selected to collect and analyze participant holistic perspective assessment of effectiveness, relevance, and timeliness of the instructional design management model. Participants for this study included five managers, five subject matter experts, and six students assigned to a military organization responsible for the collection of hydrographic data for the U.S. Navy. Triangulation of data sources within the qualitative framework of the study incorporated the three participant groups---managers, SMEs, and students---incorporated multiple views of the course development and implementation to validate the findings and the remove researcher bias. Qualitative coding was accomplished by importing transcribed interviews into Microsoft Excel and sorted using Auto-Filter. The coded interviews indicated effective functionality in the views of the model from each of the three participant groups. Results from a pre-test/post-test comparative analysis indicated a significant difference between the pre-test and post-test mean at the p < .001 for the six students. Although the subject of the case study was within a military training environment, the application of the proposed instructional systems managerial model can be applied to the design, development, delivery, and assessment of instructional material in any line of study where quantifiable effective learning is the goal.
78 FR 40149 - Scientific Information Request on Chronic Urinary Retention (CUR) Treatment
Federal Register 2010, 2011, 2012, 2013, 2014
2013-07-03
... improve the quality of this review. AHRQ is conducting this comparative effectiveness review pursuant to..., study period, design, methodology, indication and diagnosis, proper use instructions, inclusion and... study number, the study period, design, methodology, indication and diagnosis, proper use instructions...
Job design, employment practices and well-being: a systematic review of intervention studies.
Daniels, Kevin; Gedikli, Cigdem; Watson, David; Semkina, Antonina; Vaughn, Oluwafunmilayo
2017-09-01
There is inconsistent evidence that deliberate attempts to improve job design realise improvements in well-being. We investigated the role of other employment practices, either as instruments for job redesign or as instruments that augment job redesign. Our primary outcome was well-being. Where studies also assessed performance, we considered performance as an outcome. We reviewed 33 intervention studies. We found that well-being and performance may be improved by: training workers to improve their own jobs; training coupled with job redesign; and system wide approaches that simultaneously enhance job design and a range of other employment practices. We found insufficient evidence to make any firm conclusions concerning the effects of training managers in job redesign and that participatory approaches to improving job design have mixed effects. Successful implementation of interventions was associated with worker involvement and engagement with interventions, managerial commitment to interventions and integration of interventions with other organisational systems. Practitioner Summary: Improvements in well-being and performance may be associated with system-wide approaches that simultaneously enhance job design, introduce a range of other employment practices and focus on worker welfare. Training may have a role in initiating job redesign or augmenting the effects of job design on well-being.
NASA Astrophysics Data System (ADS)
Treichel, A.; Huisman, J. A.; Zhao, Y.; Zimmermann, E.; Esser, O.; Kemna, A.; Vereecken, H.
2012-12-01
Geophysical measurements within a borehole are typically affected by the presence of the borehole. The focus of the current study is to quantify the effect of borehole design on broadband electrical impedance tomography (EIT) measurements within boreholes. Previous studies have shown that effects on the real part of the electrical resistivity are largest for boreholes with large diameters and for materials with a large formation factor. However, these studies have not considered the effect of the well casing and the filter gravel on the measurement of the real part of the electrical resistivity. In addition, the effect of borehole design on the imaginary part of the electrical resistivity has not been investigated yet. Therefore, the aim of this study is to investigate the effect of borehole design on the complex electrical resistivity using laboratory measurements and numerical simulations. In order to do so, we developed a high resolution two dimensional axisymmetric finite element model (FE) that enables us to simulate the effects of several key borehole design parameters (e.g. borehole diameter, thickness of PVC well casing) on the measurement process. For the material surrounding the borehole, realistic values for complex resistivity were obtained from a database of laboratory measurements of complex resistivity from the test site Krauthausen (Germany). The slotted PVC well casing is represented by an effective resistivity calculated from the water-filled slot volume and the PVC volume. Measurements with and without PVC well casing were made with a four-electrode EIT logging tool in a water-filled rain barrel. The initial comparison for the case that the logging tool was inserted in the PVC well casing showed a considerable mismatch between measured and modeled values. It was required to consider a complete electrode model instead of point electrodes to remove this mismatch. This validated model was used to investigate in detail how complex resistivity measurements with different electrode configurations are affected by borehole design. Finally, the plausibility of our results was verified by comparing the simulation results with borehole EIT measurements made at the test site Krauthausen.
Using Story Structure for Lesson Design in Teaching about Sexual Assault
ERIC Educational Resources Information Center
Erbe, Ryan G.; Kearns, Katherine D.
2016-01-01
The present pilot study examines the use of story structure for lesson design to promote student engagement in a lesson focusing on sexual assault prevention. The effect of the story-based lesson on undergraduates' knowledge and perceptions of sexual assault was studied using a quasi-experimental mixed methods design. Results of the study…
Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-14
... Communication Research will design and administer the study. The proposed study will assess consumers' emotional... will help FDA to design more effective consumer food recall messages during and after a recall. FDA... collection of information is 354 hours (table 1 of this document). To help design and refine the...
ERIC Educational Resources Information Center
Xu, Zeyu; Nichols, Austin
2010-01-01
The gold standard in making causal inference on program effects is a randomized trial. Most randomization designs in education randomize classrooms or schools rather than individual students. Such "clustered randomization" designs have one principal drawback: They tend to have limited statistical power or precision. This study aims to…
ERIC Educational Resources Information Center
Sun, Jing; Prenzler, Tim; Buys, Nicholas; McMeniman, Marilyn
2012-01-01
Purpose: The purpose of the study was to evaluate the effectiveness of interventions using situational crime prevention approaches to reduce the smoking rate in outdoor areas of a university campus. Design/methodology/approach: A prospective intervention design was designed for the study. Surveys and observations were used to measure the impacts…
Effects of a School-Based Sexuality Education Program on Peer Educators: The Teen PEP Model
ERIC Educational Resources Information Center
Jennings, J. M.; Howard, S.; Perotte, C. L.
2014-01-01
This study evaluated the impact of the Teen Prevention Education Program (Teen PEP), a peer-led sexuality education program designed to prevent unintended pregnancy and sexually transmitted infections (STIs) including HIV among high school students. The study design was a quasi-experimental, nonrandomized design conducted from May 2007 to May…
NASA Astrophysics Data System (ADS)
Bai, Wen; Dai, Junwu; Zhou, Huimeng; Yang, Yongqiang; Ning, Xiaoqing
2017-10-01
Porcelain electrical equipment (PEE), such as current transformers, is critical to power supply systems, but its seismic performance during past earthquakes has not been satisfactory. This paper studies the seismic performance of two typical types of PEE and proposes a damping method for PEE based on multiple tuned mass dampers (MTMD). An MTMD damping device involving three mass units, named a triple tuned mass damper (TTMD), is designed and manufactured. Through shake table tests and finite element analysis, the dynamic characteristics of the PEE are studied and the effectiveness of the MTMD damping method is verified. The adverse influence of MTMD redundant mass to damping efficiency is studied and relevant equations are derived. MTMD robustness is verified through adjusting TTMD control frequencies. The damping effectiveness of TTMD, when the peak ground acceleration far exceeds the design value, is studied. Both shake table tests and finite element analysis indicate that MTMD is effective and robust in attenuating PEE seismic responses. TTMD remains effective when the PGA far exceeds the design value and when control deviations are considered.
Talboom-Kamp, E P W A; Verdijk, N A; Blom, C M G; Harmans, L M; Talboom, I J S H; Numans, M E; Chavannes, N H
2016-08-17
COPD is a highly complex disease to manage as patients show great variation in symptoms and limitations in daily life. In the last decade self-management support of COPD has been introduced as an effective method to improve quality and efficiency of care, and to reduce healthcare costs. Despite the urge to change the organisation of health care and the potential of eHealth to support this, large-scale implementation in daily practice remains behind, especially in the Netherlands. We designed a multilevel study, called e-Vita, to investigate different organisational implementation methods of a self-management web portal to support and empower patients with COPD in three different primary care settings. Using a parallel cohort design, the clinical effects of the web portal will be assessed using an interrupted times series (ITS) study design and measured according to changes in health status with the Clinical COPD Questionnaire (CCQ). The different implementations and net benefits of self-management through eHealth on clinical outcomes will be evaluated from human, organisational, and technical perspectives. To our knowledge this is the first study to combine different study designs that enable simultaneous investigation of clinical effects, as well as effects of different organisational implementation methods whilst controlling for confounding effects of the organisational characteristics. We hypothesize that an implementation with higher levels of personal assistance, and integrated in an existing care program will result in increased use of and satisfaction with the platform, thereby increasing health status and diminishing exacerbation and hospitalisation. NTR4098 (31-07-2013).
Talboom-Kamp, E P W A; Verdijk, N A; Blom, C M G; Harmans, L M; Talboom, I J S H; Numans, M E; Chavannes, N H
2016-08-16
COPD is a highly complex disease to manage as patients show great variation in symptoms and limitations in daily life. In the last decade self-management support of COPD has been introduced as an effective method to improve quality and efficiency of care, and to reduce healthcare costs. Despite the urge to change the organisation of health care and the potential of eHealth to support this, large-scale implementation in daily practice remains behind, especially in the Netherlands. We designed a multilevel study, called e-Vita, to investigate different organisational implementation methods of a self-management web portal to support and empower patients with COPD in three different primary care settings. Using a parallel cohort design, the clinical effects of the web portal will be assessed using an interrupted times series (ITS) study design and measured according to changes in health status with the Clinical COPD Questionnaire (CCQ). The different implementations and net benefits of self-management through eHealth on clinical outcomes will be evaluated from human, organisational, and technical perspectives. To our knowledge this is the first study to combine different study designs that enable simultaneous investigation of clinical effects, as well as effects of different organisational implementation methods whilst controlling for confounding effects of the organisational characteristics. We hypothesize that an implementation with higher levels of personal assistance, and integrated in an existing care program will result in increased use of and satisfaction with the platform, thereby increasing health status and diminishing exacerbation and hospitalisation. NTR4098 (31-07-2013).
Sun, Zhichao; Mukherjee, Bhramar; Estes, Jason P; Vokonas, Pantel S; Park, Sung Kyun
2017-08-15
Joint effects of genetic and environmental factors have been increasingly recognized in the development of many complex human diseases. Despite the popularity of case-control and case-only designs, longitudinal cohort studies that can capture time-varying outcome and exposure information have long been recommended for gene-environment (G × E) interactions. To date, literature on sampling designs for longitudinal studies of G × E interaction is quite limited. We therefore consider designs that can prioritize a subsample of the existing cohort for retrospective genotyping on the basis of currently available outcome, exposure, and covariate data. In this work, we propose stratified sampling based on summaries of individual exposures and outcome trajectories and develop a full conditional likelihood approach for estimation that adjusts for the biased sample. We compare the performance of our proposed design and analysis with combinations of different sampling designs and estimation approaches via simulation. We observe that the full conditional likelihood provides improved estimates for the G × E interaction and joint exposure effects over uncorrected complete-case analysis, and the exposure enriched outcome trajectory dependent design outperforms other designs in terms of estimation efficiency and power for detection of the G × E interaction. We also illustrate our design and analysis using data from the Normative Aging Study, an ongoing longitudinal cohort study initiated by the Veterans Administration in 1963. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.
The Role of Formal Experiment Design in Hypersonic Flight System Technology Development
NASA Technical Reports Server (NTRS)
McClinton, Charles R.; Ferlemann, Shelly M.; Rock, Ken E.; Ferlemann, Paul G.
2002-01-01
Hypersonic airbreathing engine (scramjet) powered vehicles are being considered to replace conventional rocket-powered launch systems. Effective utilization of scramjet engines requires careful integration with the air vehicle. This integration synergistically combines aerodynamic forces with propulsive cycle functions of the engine. Due to the highly integrated nature of the hypersonic vehicle design problem, the large flight envelope, and the large number of design variables, the use of a statistical design approach in design is effective. Modern Design-of-Experiments (MDOE) has been used throughout the Hyper-X program, for both systems analysis and experimental testing. Application of MDOE fall into four categories: (1) experimental testing; (2) studies of unit phenomena; (3) refining engine design; and (4) full vehicle system optimization. The MDOE process also provides analytical models, which are also used to document lessons learned, supplement low-level design tools, and accelerate future studies. This paper will discuss the design considerations for scramjet-powered vehicles, specifics of MDOE utilized for Hyper-X, and present highlights from the use of these MDOE methods within the Hyper-X Program.
Roadmap to Measuring Distance Education Instructional Design Competencies
ERIC Educational Resources Information Center
Dooley, Kim E.; Lindner, James R.; Telg, Ricky W.; Irani, Tracy; Moore, Lori; Lundy, Lisa
2007-01-01
This study was designed to measure instructional design competencies as a result of participation in a 9-month Web-based training program called "Roadmap to Effective Distance Education Instructional Design." The researchers used a self-assessment pre- and posttest to determine participant initial and final competence in 12 areas: adult…
An Annotated Bibliography of the Manned Systems Measurement Literature
1985-02-01
designs that are considered applicable to assessment of training effectiveness include the classic Solomon four - group design; iterative adaptation to...element (analogue computer) were used for this study . *».U Operators were taken from 3 groups : (1) persons with both licensed flying and driving...conclusions are that the classic four - group design is impractical for most training evaluation; that "adaptive research for big effects" is apt to be
ERIC Educational Resources Information Center
Rosenzweig, Emily Quinn
2017-01-01
In the present study I developed and evaluated the effects of two interventions designed to target students' motivation to learn in an introductory college physics course. One intervention was designed to improve students' perceptions of utility value and the other was designed to reduce students' perceptions of cost. Utility value and cost both…
NASA Astrophysics Data System (ADS)
Baukal, Charles E.; Ausburn, Lynna J.
2017-05-01
Continuing engineering education (CEE) is important to ensure engineers maintain proficiency over the life of their careers. However, relatively few studies have examined designing effective training for working engineers. Research has indicated that both learner instructional preferences and prior knowledge can impact the learning process, but it has not established if these factors are interrelated. The study reported here considered relationships of prior knowledge and three aspects of learning preferences of working engineers at a manufacturing company: learning strategy choices, verbal-visual cognitive styles, and multimedia preferences. Prior knowledge was not found to be significantly related to engineers' learning preferences, indicating independence of effects of these variables on learning. The study also examined relationships of this finding to the Multimedia Cone of Abstraction and implications for its use as an instructional design tool for CEE.
A Parametric Geometry Computational Fluid Dynamics (CFD) Study Utilizing Design of Experiments (DOE)
NASA Technical Reports Server (NTRS)
Rhew, Ray D.; Parker, Peter A.
2007-01-01
Design of Experiments (DOE) was applied to the LAS geometric parameter study to efficiently identify and rank primary contributors to integrated drag over the vehicles ascent trajectory in an order of magnitude fewer CFD configurations thereby reducing computational resources and solution time. SME s were able to gain a better understanding on the underlying flowphysics of different geometric parameter configurations through the identification of interaction effects. An interaction effect, which describes how the effect of one factor changes with respect to the levels of other factors, is often the key to product optimization. A DOE approach emphasizes a sequential approach to learning through successive experimentation to continuously build on previous knowledge. These studies represent a starting point for expanded experimental activities that will eventually cover the entire design space of the vehicle and flight trajectory.
The Power of Effective Design in e-Learning: A Study of the "Mayo Effect" Video
ERIC Educational Resources Information Center
Fan, Jiang Ping
2014-01-01
When the Mayo Effect video went live on the Mayo intranet in June 2010, it was very well received at Mayo Clinic. The message in the video was so effectively delivered that it became an instant sensation across the institution. The video contains about 461 words. In such a short video, every part of its architectural design, whether it is visual,…
Youth Employability Training: Two Experiments
ERIC Educational Resources Information Center
Brown, Travor; Hillier, Tara-Lynn; Warren, Amy M.
2010-01-01
Purpose: This paper aims to assess the effectiveness of verbal self-guidance (VSG) and self-management on youth employability. It seeks to access the joint effectiveness of these interventions, grounded in social cognitive and goal setting theories, for youth job seekers. Design/methodology/approach: The studies used experimental designs involving…
ERIC Educational Resources Information Center
Siko, Jason Paul
2012-01-01
This design-based research study examined the effects of a game design project on student test performance, with refinements made to the implementation after each of the three iterations of the study. The changes to the implementation over the three iterations were based on the literature for the three justifications for the use of homemade…
The Seated Soldier Study: Posture and Body Shape in Vehicle Seats
2014-01-28
vehicle interior layout Current design guidance is based on outdated anthropometry Previous studies of seated anthropometry have not included the...personal protective equipment (PPE) for seat and vehicle interior layout • Current design guidance is based on outdated anthropometry • Previous...studies of seated anthropometry have not included the effects of PPE on posture and body shape • Detailed anthropometric data needed for the design
Design and Analysis of a Subcritical Airfoil for High Altitude, Long Endurance Missions.
1982-12-01
Airfoil Design and Analysis Method ......... .... 61 Appendix D: Boundary Layer Analysis Method ............. ... 81 Appendix E: Detailed Results ofr...attack. Computer codes designed by Richard Eppler were used for this study. The airfoil was anlayzed by using a viscous effects analysis program...inverse program designed by Eppler (Ref 5) was used in this study to accomplish this part. The second step involved the analysis of the airfoil under
Mantzorou, Maria; Pavlidou, Eleni; Vasios, George; Tsagalioti, Eftychia; Giaginis, Constantinos
2018-06-01
Numerous clinical trials have investigated the potential beneficial effects of curcumin supplementation against several human chronic diseases. Up to now, it has been claimed that curcumin consumption may exert beneficial effects against several chronic diseases by promoting human health and preventing diseases. In this aspect, the present review aims to critically collect and in-depth summarize the most recent, well-designed clinical studies evaluating the potential beneficial effects of curcumin consumption on human health promotion and disease prevention. According to recent and well-designed clinical studies, curcumin consumption may benefit against obesity, metabolic syndrome, and diabetes. Moreover, curcumin consumption seems to exert a positive effect on people suffering from various types of cancer, fatty liver disease, depression, arthritis, skin diseases, gut inflammation, and symptoms of premenstrual syndrome. Due to the strong heterogeneity among the clinical studies concerning the exact effective curcumin dose and formulation, as well as the recommended treatment duration for each chronic disease, no precise and definitive conclusions could be drawn. Further large-scale prospective studies are strongly recommended, being well-designed as far as follow-up times, dosage, formulation, and duration of curcumin supplementation are concerned. Moreover, potential confounders in each specific chronic disease should carefully be taken into account in future studies. Copyright © 2018 John Wiley & Sons, Ltd.
Design of a cost-effective laser spot tracker
NASA Astrophysics Data System (ADS)
Artan, Göktuǧ Gencehan; Sari, Hüseyin
2017-05-01
One of the most important aspects of guided systems is detection. The most convenient detection in the sense of precision can be achieved with a laser spot tracker. This study deals with a military grade, high performance and cost-effective laser spot tracker for a guided system. The aim is to develop a high field of view system that will detect a laser spot from a distance of 3 kilometers in which the target is designated from 3 kilometers with a laser. The study basically consists of the system design, modeling, producing and the conducting performance tests of the whole system.
Steep discounting of delayed monetary and food rewards in obesity: a meta-analysis.
Amlung, M; Petker, T; Jackson, J; Balodis, I; MacKillop, J
2016-08-01
An increasing number of studies have investigated delay discounting (DD) in relation to obesity, but with mixed findings. This meta-analysis synthesized the literature on the relationship between monetary and food DD and obesity, with three objectives: (1) to characterize the relationship between DD and obesity in both case-control comparisons and continuous designs; (2) to examine potential moderators, including case-control v. continuous design, money v. food rewards, sample sex distribution, and sample age (18 years); and (3) to evaluate publication bias. From 134 candidate articles, 39 independent investigations yielded 29 case-control and 30 continuous comparisons (total n = 10 278). Random-effects meta-analysis was conducted using Cohen's d as the effect size. Publication bias was evaluated using fail-safe N, Begg-Mazumdar and Egger tests, meta-regression of publication year and effect size, and imputation of missing studies. The primary analysis revealed a medium effect size across studies that was highly statistically significant (d = 0.43, p < 10-14). None of the moderators examined yielded statistically significant differences, although notably larger effect sizes were found for studies with case-control designs, food rewards and child/adolescent samples. Limited evidence of publication bias was present, although the Begg-Mazumdar test and meta-regression suggested a slightly diminishing effect size over time. Steep DD of food and money appears to be a robust feature of obesity that is relatively consistent across the DD assessment methodologies and study designs examined. These findings are discussed in the context of research on DD in drug addiction, the neural bases of DD in obesity, and potential clinical applications.
Bougma, Karim; Aboud, Frances E; Harding, Kimberly B; Marquis, Grace S
2013-04-22
Several reviews and meta-analyses have examined the effects of iodine on mental development. None focused on young children, so they were incomplete in summarizing the effects on this important age group. The current systematic review therefore examined the relationship between iodine and mental development of children 5 years old and under. A systematic review of articles using Medline (1980-November 2011) was carried out. We organized studies according to four designs: (1) randomized controlled trial with iodine supplementation of mothers; (2) non-randomized trial with iodine supplementation of mothers and/or infants; (3) prospective cohort study stratified by pregnant women's iodine status; (4) prospective cohort study stratified by newborn iodine status. Average effect sizes for these four designs were 0.68 (2 RCT studies), 0.46 (8 non-RCT studies), 0.52 (9 cohort stratified by mothers' iodine status), and 0.54 (4 cohort stratified by infants' iodine status). This translates into 6.9 to 10.2 IQ points lower in iodine deficient children compared with iodine replete children. Thus, regardless of study design, iodine deficiency had a substantial impact on mental development. Methodological concerns included weak study designs, the omission of important confounders, small sample sizes, the lack of cluster analyses, and the lack of separate analyses of verbal and non-verbal subtests. Quantifying more precisely the contribution of iodine deficiency to delayed mental development in young children requires more well-designed randomized controlled trials, including ones on the role of iodized salt.
Benefit design innovations: implications for consumer-directed health care.
Tu, Ha T; Ginsburg, Paul B
2007-02-01
Current health insurance benefit designs that simply rely on higher, one-size-fits-all patient cost sharing have limited potential to curb rapidly rising costs, but innovations in benefit design can potentially make cost sharing a more effective tool, according to a new study by the Center for Studying Health System Change (HSC). Innovative benefit designs include incentives to encourage healthy behaviors; incentives that vary by service type, patient condition or enrollee income; and incentives to use efficient providers. But most applications of these innovative designs are not widespread, suggesting that any significant cost impact is many years off. Moreover, regulations governing high-deductible, consumer-directed health plans eligible for health savings accounts (HSAs) preclude some promising benefit design innovations and dilute the incentives in others. A movement away from a one-size-fits-all HSA benefit structure toward a more flexible design might broaden the appeal of HSA plans and enable them to incorporate features that promote cost-effective care.
Preliminary Sizing Study of Ares-I and Ares-V Liquid Hydrogen Tanks
NASA Technical Reports Server (NTRS)
Oliver, Stanley T.; Harper, David W.
2012-01-01
A preliminary sizing study of two cryogenic propellant tanks was performed using a FORTRAN optimization program to determine weight efficient orthogrid designs for the tank barrels sections only. Various tensile and compressive failure modes were considered, including general buckling of cylinders with a shell buckling knockdown factor. Eight independent combinations of three design requirements were also considered and their effects on the tanks weight. The approach was to investigate each design case with a variable shell buckling knockdown factor, determining the most weight efficient combination of orthogrid design parameters. Numerous optimization analyses were performed, and the results presented herein compare the effects of the different design requirements and shell buckling knockdown factor. Through a series of comparisons between design requirements or shell buckling knockdown factors, the relative change in overall tank barrel weights is shown. The findings indicate that the design requirements can substantually increase the tank weight while a less conservative shell buckling knockdown factor can modestly reduce the tank weight.
The Effects of Interior Design on Communication and Impressions of a Counselor in a Counseling Room
ERIC Educational Resources Information Center
Miwa, Yoshiko; Hanyu, Kazunori
2006-01-01
This study aimed to investigate effects of the interior design of a counseling room on participants' self-disclosure and impressions of a counselor. The authors examined the effects of lighting and decorations. It tested four conditions crossing decorations (with or without home-like decorations) and type of lighting (bright or dim). Eighty…
Luce, Bryan R; Broglio, Kristine R; Ishak, K Jack; Mullins, C Daniel; Vanness, David J; Fleurence, Rachael; Saunders, Elijah; Davis, Barry R
2013-01-01
Background Randomized clinical trials, particularly for comparative effectiveness research (CER), are frequently criticized for being overly restrictive or untimely for health-care decision making. Purpose Our prospectively designed REsearch in ADAptive methods for Pragmatic Trials (RE-ADAPT) study is a ‘proof of concept’ to stimulate investment in Bayesian adaptive designs for future CER trials. Methods We will assess whether Bayesian adaptive designs offer potential efficiencies in CER by simulating a re-execution of the Antihypertensive and Lipid Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) study using actual data from ALLHAT. Results We prospectively define seven alternate designs consisting of various combinations of arm dropping, adaptive randomization, and early stopping and describe how these designs will be compared to the original ALLHAT design. We identify the one particular design that would have been executed, which incorporates early stopping and information-based adaptive randomization. Limitations While the simulation realistically emulates patient enrollment, interim analyses, and adaptive changes to design, it cannot incorporate key features like the involvement of data monitoring committee in making decisions about adaptive changes. Conclusion This article describes our analytic approach for RE-ADAPT. The next stage of the project is to conduct the re-execution analyses using the seven prespecified designs and the original ALLHAT data. PMID:23983160
Robustness of crossover trials against subject drop-out - Examples of perpetually connected designs.
Godolphin, P J; Godolphin, E J
2017-01-01
When performing a repeated measures experiment, such as a clinical trial, there is a risk of subject drop-out during the experiment. If one or more subjects leave the study prematurely, a situation could arise where the eventual design is disconnected, implying that very few treatment contrasts for both direct effects and carryover effects are estimable. This paper aims to identify experimental conditions where this problem with the eventual design can be avoided. It is shown that in the class of uniformly balanced repeated measurement designs consisting of two or more Latin squares, there are planned designs with the following useful property. Provided that all subjects have completed the first two periods of study, such a design will not be replaced by a disconnected eventual design due to drop-out, irrespective of the type of drop-out behaviour that may occur. Designs with this property are referred to as perpetually connected. These experimental conditions are identified and examined in the paper and an example of at least one perpetually connected uniformly balanced repeated measurement design is given in each case. The results improve upon previous contributions in the literature that have been confined largely to cases in which drop-out occurs only in the final periods of study.
Design for interaction between humans and intelligent systems during real-time fault management
NASA Technical Reports Server (NTRS)
Malin, Jane T.; Schreckenghost, Debra L.; Thronesbery, Carroll G.
1992-01-01
Initial results are reported to provide guidance and assistance for designers of intelligent systems and their human interfaces. The objective is to achieve more effective human-computer interaction (HCI) for real time fault management support systems. Studies of the development of intelligent fault management systems within NASA have resulted in a new perspective of the user. If the user is viewed as one of the subsystems in a heterogeneous, distributed system, system design becomes the design of a flexible architecture for accomplishing system tasks with both human and computer agents. HCI requirements and design should be distinguished from user interface (displays and controls) requirements and design. Effective HCI design for multi-agent systems requires explicit identification of activities and information that support coordination and communication between agents. The effects are characterized of HCI design on overall system design and approaches are identified to addressing HCI requirements in system design. The results include definition of (1) guidance based on information level requirements analysis of HCI, (2) high level requirements for a design methodology that integrates the HCI perspective into system design, and (3) requirements for embedding HCI design tools into intelligent system development environments.
Placebo effect in clinical trial design for irritable bowel syndrome.
Shah, Eric; Pimentel, Mark
2014-04-30
Ongoing efforts to improve clinical trial design in irritable bowel syndrome have been hindered by high placebo response rates and ineffective outcome measures. We assessed established strategies to minimize placebo effect as well as the various ap-proaches to placebo effect which can affect trial design. These include genetic markers such as catechol-O-methyltransferase, opioidergic and dopaminergic neurobiologic theory, pre-cebo effect centered on expectancy theory, and side effect unblinding grounded on conditioning theory. We reviewed endpoints used in the study of IBS over the past decade including adequate relief and subjective global relief, emphasizing their weaknesses in fully evaluating the IBS condition, specifically their motility effects based on functional net value and relative benefit-harm based on dropouts due to adverse events. The focus of this review is to highlight ongoing efforts to improve clinical trial design which can lead to better outcomes in a real-world setting.
Design considerations for genetic linkage and association studies.
Nsengimana, Jérémie; Bishop, D Timothy
2012-01-01
This chapter describes the main issues that genetic epidemiologists usually consider in the design of linkage and association studies. For linkage, we briefly consider the situation of rare, highly penetrant alleles showing a disease pattern consistent with Mendelian inheritance investigated through parametric methods in large pedigrees or with autozygosity mapping in inbred families, and we then turn our focus to the most common design, affected sibling pairs, of more relevance for common, complex diseases. Theoretical and more practical power and sample size calculations are provided as a function of the strength of the genetic effect being investigated. We also discuss the impact of other determinants of statistical power such as disease heterogeneity, pedigree, and genotyping errors, as well as the effect of the type and density of genetic markers. Linkage studies should be as large as possible to have sufficient power in relation to the expected genetic effect size. Segregation analysis, a formal statistical technique to describe the underlying genetic susceptibility, may assist in the estimation of the relevant parameters to apply, for instance. However, segregation analyses estimate the total genetic component rather than a single-locus effect. Locus heterogeneity should be considered when power is estimated and at the analysis stage, i.e. assuming smaller locus effect than the total the genetic component from segregation studies. Disease heterogeneity should be minimised by considering subtypes if they are well defined or by otherwise collecting known sources of heterogeneity and adjusting for them as covariates; the power will depend upon the relationship between the disease subtype and the underlying genotypes. Ultimately, identifying susceptibility alleles of modest effects (e.g. RR≤1.5) requires a number of families that seem unfeasible in a single study. Meta-analysis and data pooling between different research groups can provide a sizeable study, but both approaches require even a higher level of vigilance about locus and disease heterogeneity when data come from different populations. All necessary steps should be taken to minimise pedigree and genotyping errors at the study design stage as they are, for the most part, due to human factors. A two-stage design is more cost-effective than one stage when using short tandem repeats (STRs). However, dense single-nucleotide polymorphism (SNP) arrays offer a more robust alternative, and due to their lower cost per unit, the total cost of studies using SNPs may in the future become comparable to that of studies using STRs in one or two stages. For association studies, we consider the popular case-control design for dichotomous phenotypes, and we provide power and sample size calculations for one-stage and multistage designs. For candidate genes, guidelines are given on the prioritisation of genetic variants, and for genome-wide association studies (GWAS), the issue of choosing an appropriate SNP array is discussed. A warning is issued regarding the danger of designing an underpowered replication study following an initial GWAS. The risk of finding spurious association due to population stratification, cryptic relatedness, and differential bias is underlined. GWAS have a high power to detect common variants of high or moderate effect. For weaker effects (e.g. relative risk<1.2), the power is greatly reduced, particularly for recessive loci. While sample sizes of 10,000 or 20,000 cases are not beyond reach for most common diseases, only meta-analyses and data pooling can allow attaining a study size of this magnitude for many other diseases. It is acknowledged that detecting the effects from rare alleles (i.e. frequency<5%) is not feasible in GWAS, and it is expected that novel methods and technology, such as next-generation resequencing, will fill this gap. At the current stage, the choice of which GWAS SNP array to use does not influence the power in populations of European ancestry. A multistage design reduces the study cost but has less power than the standard one-stage design. If one opts for a multistage design, the power can be improved by jointly analysing the data from different stages for the SNPs they share. The estimates of locus contribution to disease risk from genome-wide scans are often biased, and relying on them might result in an underpowered replication study. Population structure has so far caused less spurious associations than initially feared, thanks to systematic ethnicity matching and application of standard quality control measures. Differential bias could be a more serious threat and must be minimised by strictly controlling all the aspects of DNA acquisition, storage, and processing.
Off-design performance analysis of MHD generator channels
NASA Technical Reports Server (NTRS)
Wilson, D. R.; Williams, T. S.
1980-01-01
A computer code for performing parametric design point calculations, and evaluating the off-design performance of MHD generators has been developed. The program is capable of analyzing Faraday, Hall, and DCW channels, including the effect of electrical shorting in the gas boundary layers and coal slag layers. Direct integration of the electrode voltage drops is included. The program can be run in either the design or off-design mode. Details of the computer code, together with results of a study of the design and off-design performance of the proposed ETF MHD generator are presented. Design point variations of pre-heat and stoichiometry were analyzed. The off-design study included variations in mass flow rate and oxygen enrichment.
Daniel A. Marion; Jonathan D. Phillips; Chad Yocum; Stephanie H. Mehlhope
2014-01-01
This study investigates the geomorphic effects of ford-type stream crossings in an off-highway vehicle (OHV) trail complex in the Ouachita National Forest, Arkansas. At a total of 15 crossing sites, we used a disturbed vs. undisturbed study design to assess soil truncation and an upstream vs. downstream design to assess in-channel effects. The 15 sites ranged from OHV...
ERIC Educational Resources Information Center
Kocakaya, Serhat; Gonen, Selahattin
2010-01-01
The purpose of this study was to investigate the effects of a Computer-Assisted Instruction designed according to 7E model of constructivist learning(CAI7E) related to "electrostatic'' topic on physics student teachers' cognitive development, misconceptions, self-efficacy perceptions and attitudes. The study was conducted in 2006-2007…
Self-regulated learning in simulation-based training: a systematic review and meta-analysis.
Brydges, Ryan; Manzone, Julian; Shanks, David; Hatala, Rose; Hamstra, Stanley J; Zendejas, Benjamin; Cook, David A
2015-04-01
Self-regulated learning (SRL) requires an active learner who has developed a set of processes for managing the achievement of learning goals. Simulation-based training is one context in which trainees can safely practise learning how to learn. The purpose of the present study was to evaluate, in the simulation-based training context, the effectiveness of interventions designed to support trainees in SRL activities. We used the social-cognitive model of SRL to guide a systematic review and meta-analysis exploring the links between instructor supervision, supports or scaffolds for SRL, and educational outcomes. We searched databases including MEDLINE and Scopus, and previous reviews, for material published until December 2011. Studies comparing simulation-based SRL interventions with another intervention for teaching health professionals were included. Reviewers worked independently and in duplicate to extract information on learners, study quality and educational outcomes. We used random-effects meta-analysis to compare the effects of supervision (instructor present or absent) and SRL educational supports (e.g. goal-setting study guides present or absent). From 11,064 articles, we included 32 studies enrolling 2482 trainees. Only eight of the 32 studies included educational supports for SRL. Compared with instructor-supervised interventions, unsupervised interventions were associated with poorer immediate post-test outcomes (pooled effect size: -0.34, p = 0.09; n = 19 studies) and negligible effects on delayed (i.e. > 1 week) retention tests (pooled effect size: 0.11, p = 0.63; n = 8 studies). Interventions including SRL supports were associated with small benefits compared with interventions without supports on both immediate post-tests (pooled effect size: 0.23, p = 0.22; n = 5 studies) and delayed retention tests (pooled effect size: 0.44, p = 0.067; n = 3 studies). Few studies in the simulation literature have designed SRL training to explicitly support trainees' capacity to self-regulate their learning. We recommend that educators and researchers shift from thinking about SRL as learning alone to thinking of SRL as comprising a shared responsibility between the trainee and the instructional designer (i.e. learning using designed supports that help prepare individuals for future learning). © 2015 John Wiley & Sons Ltd.
From randomized controlled trials to observational studies.
Silverman, Stuart L
2009-02-01
Randomized controlled trials are considered the gold standard in the hierarchy of research designs for evaluating the efficacy and safety of a treatment intervention. However, their results can have limited applicability to patients in clinical settings. Observational studies using large health care databases can complement findings from randomized controlled trials by assessing treatment effectiveness in patients encountered in day-to-day clinical practice. Results from these designs can expand upon outcomes of randomized controlled trials because of the use of larger and more diverse patient populations with common comorbidities and longer follow-up periods. Furthermore, well-designed observational studies can identify clinically important differences among therapeutic options and provide data on long-term drug effectiveness and safety.
Evaluating the Impact of Physical Activity Apps and Wearables: Interdisciplinary Review
Rooksby, John; Gray, Cindy M
2018-01-01
Background Although many smartphone apps and wearables have been designed to improve physical activity, their rapidly evolving nature and complexity present challenges for evaluating their impact. Traditional methodologies, such as randomized controlled trials (RCTs), can be slow. To keep pace with rapid technological development, evaluations of mobile health technologies must be efficient. Rapid alternative research designs have been proposed, and efficient in-app data collection methods, including in-device sensors and device-generated logs, are available. Along with effectiveness, it is important to measure engagement (ie, users’ interaction and usage behavior) and acceptability (ie, users’ subjective perceptions and experiences) to help explain how and why apps and wearables work. Objectives This study aimed to (1) explore the extent to which evaluations of physical activity apps and wearables: employ rapid research designs; assess engagement, acceptability, as well as effectiveness; use efficient data collection methods; and (2) describe which dimensions of engagement and acceptability are assessed. Method An interdisciplinary scoping review using 8 databases from health and computing sciences. Included studies measured physical activity, and evaluated physical activity apps or wearables that provided sensor-based feedback. Results were analyzed using descriptive numerical summaries, chi-square testing, and qualitative thematic analysis. Results A total of 1829 abstracts were screened, and 858 articles read in full. Of 111 included studies, 61 (55.0%) were published between 2015 and 2017. Most (55.0%, 61/111) were RCTs, and only 2 studies (1.8%) used rapid research designs: 1 single-case design and 1 multiphase optimization strategy. Other research designs included 23 (22.5%) repeated measures designs, 11 (9.9%) nonrandomized group designs, 10 (9.0%) case studies, and 4 (3.6%) observational studies. Less than one-third of the studies (32.0%, 35/111) investigated effectiveness, engagement, and acceptability together. To measure physical activity, most studies (90.1%, 101/111) employed sensors (either in-device [67.6%, 75/111] or external [23.4%, 26/111]). RCTs were more likely to employ external sensors (accelerometers: P=.005). Studies that assessed engagement (52.3%, 58/111) mostly used device-generated logs (91%, 53/58) to measure the frequency, depth, and length of engagement. Studies that assessed acceptability (57.7%, 64/111) most often used questionnaires (64%, 42/64) and/or qualitative methods (53%, 34/64) to explore appreciation, perceived effectiveness and usefulness, satisfaction, intention to continue use, and social acceptability. Some studies (14.4%, 16/111) assessed dimensions more closely related to usability (ie, burden of sensor wear and use, interface complexity, and perceived technical performance). Conclusions The rapid increase of research into the impact of physical activity apps and wearables means that evaluation guidelines are urgently needed to promote efficiency through the use of rapid research designs, in-device sensors and user-logs to assess effectiveness, engagement, and acceptability. Screening articles was time-consuming because reporting across health and computing sciences lacked standardization. Reporting guidelines are therefore needed to facilitate the synthesis of evidence across disciplines. PMID:29572200
Liu, Songbai; Sang, Ruocheng; Hong, Shan; Cai, Yujing; Wang, Hua
2013-07-09
A novel type of highly effective gemini alkyl glucosides has been rationally designed and synthesized. The gemini surfactants have been readily prepared by glycosylation of the gemini alkyl chains that are synthesized with regioselective ring-opening of ethylene glycol epoxides by the alkyl alcohols. The new gemini alkyl glucosides exhibit significantly better surface activity than the known results. Then rheological, DLS, and TEM studies have revealed the intriguing self-assembly behavior of the novel gemini surfactants. This study has proved the effectiveness of the design of gemini alkyl glucosides which is modular, extendable, and synthetically simple. The new gemini surfactants have great potential as nano carriers in drug and gene delivery.
Design of a laboratory study of contaminant film darkening in space
NASA Astrophysics Data System (ADS)
Judeikis, H. S.; Arnold, G. S.; Hill, M.; Young Owl, R. C.; Hall, D. F.
This paper reports the philosophy, design, and initial results of a program aimed at improving control of the optical effects of contamination in the design of a spacecraft. The types of basic data needed to produce criteria for the selection of spacecraft material based on the effects of the contaminant films they produce are discussed. The results of a spacecraft nonmetallic materials list analysis and radiation sensitivity estimates are presented. A rationale is given for simulation analysis of the potential effects of the geosynchronous environment on organic contaminant films.
Campbell, Aimee N C; Nunes, Edward V; Miele, Gloria M; Matthews, Abigail; Polsky, Daniel; Ghitza, Udi E; Turrigiano, Eva; Bailey, Genie L; VanVeldhuisen, Paul; Chapdelaine, Rita; Froias, Autumn; Stitzer, Maxine L; Carroll, Kathleen M; Winhusen, Theresa; Clingerman, Sara; Perez, Livangelie; McClure, Erin; Goldman, Bruce; Crowell, A Rebecca
2012-03-01
Computer-assisted interventions hold the promise of minimizing two problems that are ubiquitous in substance abuse treatment: the lack of ready access to treatment and the challenges to providing empirically-supported treatments. Reviews of research on computer-assisted treatments for mental health and substance abuse report promising findings, but study quality and methodological limitations remain an issue. In addition, relatively few computer-assisted treatments have been tested among illicit substance users. This manuscript describes the methodological considerations of a multi-site effectiveness trial conducted within the National Institute on Drug Abuse's (NIDA's) National Drug Abuse Treatment Clinical Trials Network (CTN). The study is evaluating a web-based version of the Community Reinforcement Approach, in addition to prize-based contingency management, among 500 participants enrolled in 10 outpatient substance abuse treatment programs. Several potential effectiveness trial designs were considered and the rationale for the choice of design in this study is described. The study uses a randomized controlled design (with independent treatment arm allocation), intention-to-treat primary outcome analysis, biological markers for the primary outcome of abstinence, long-term follow-up assessments, precise measurement of intervention dose, and a cost-effectiveness analysis. Input from community providers during protocol development highlighted potential concerns and helped to address issues of practicality and feasibility. Collaboration between providers and investigators supports the utility of infrastructures that enhance research partnerships to facilitate effectiveness trials and dissemination of promising, technologically innovative treatments. Outcomes from this study will further the empirical knowledge base on the effectiveness and cost-effectiveness of computer-assisted treatment in clinical treatment settings. Copyright © 2011 Elsevier Inc. All rights reserved.
Campbell, Aimee N. C.; Nunes, Edward V.; Miele, Gloria M.; Matthews, Abigail; Polsky, Daniel; Ghitza, Udi E.; Turrigiano, Eva; Bailey, Genie L.; VanVeldhuisen, Paul; Chapdelaine, Rita; Froias, Autumn; Stitzer, Maxine L.; Carroll, Kathleen M.; Winhusen, Theresa; Clingerman, Sara; Perez, Livangelie; McClure, Erin; Goldman, Bruce; Crowell, A. Rebecca
2011-01-01
Computer-assisted interventions hold the promise of minimizing two problems that are ubiquitous in substance abuse treatment: the lack of ready access to treatment and the challenges to providing empirically-supported treatments. Reviews of research on computer-assisted treatments for mental health and substance abuse report promising findings, but study quality and methodological limitations remain an issue. In addition, relatively few computer-assisted treatments have been tested among illicit substance users. This manuscript describes the methodological considerations of a multi-site effectiveness trial conducted within the National Institute on Drug Abuse's (NIDA's) National Drug Abuse Treatment Clinical Trials Network (CTN). The study is evaluating a web-based version of the Community Reinforcement Approach, in addition to prize-based contingency management, among 500 participants enrolled in 10 outpatient substance abuse treatment programs. Several potential effectiveness trial designs were considered and the rationale for the choice of design in this study is described. The study uses a randomized controlled design (with independent treatment arm allocation), intention-to-treat primary outcome analysis, biological markers for the primary outcome of abstinence, long-term follow-up assessments, precise measurement of intervention dose, and a cost-effectiveness analysis. Input from community providers during protocol development highlighted potential concerns and helped to address issues of practicality and feasibility. Collaboration between providers and investigators supports the utility of infrastructures that enhance research partnerships to facilitate effectiveness trials and dissemination of promising, technologically innovative treatments. Outcomes from this study will further the empirical knowledge base on the effectiveness and cost-effectiveness of computer-assisted treatment in clinical treatment settings. PMID:22085803
Polus, Stephanie; Pieper, Dawid; Burns, Jacob; Fretheim, Atle; Ramsay, Craig; Higgins, Julian P T; Mathes, Tim; Pfadenhauer, Lisa M; Rehfuess, Eva A
2017-11-01
The aim of the study was to examine the application, design, and analysis characteristics of controlled before-after (CBA) and interrupted time series (ITS) studies and their use in Cochrane reviews. We searched the Cochrane library for reviews including these study designs from May 2012 to March 2015 and purposively selected, where available, two reviews each across 10 prespecified intervention types. We randomly selected two CBA and two ITS studies from each review. Two researchers independently extracted information from the studies and the respective reviews. Sixty-nine reviews considered CBA and ITS studies for inclusion. We analyzed 21 CBA and 16 ITS studies from 11 to 8 reviews, respectively. Cochrane reviews inconsistently defined and labeled CBA and ITS studies. Many studies did not meet the Cochrane definition or the minimum criteria provided by Cochrane Effective Practice and Organisation of Care. The studies present a heterogeneous set of study features and applied a large variety of analyses. While CBA and ITS studies represent important study designs to evaluate the effects of interventions, especially on a population or organizational level, unclear study design features challenge unequivocal classification and appropriate use. We discuss options for more specific definitions and explicit criteria for CBA and ITS studies. Copyright © 2017 Elsevier Inc. All rights reserved.
Moeyaert, Mariola; Ugille, Maaike; Ferron, John M; Beretvas, S Natasha; Van den Noortgate, Wim
2014-09-01
The quantitative methods for analyzing single-subject experimental data have expanded during the last decade, including the use of regression models to statistically analyze the data, but still a lot of questions remain. One question is how to specify predictors in a regression model to account for the specifics of the design and estimate the effect size of interest. These quantitative effect sizes are used in retrospective analyses and allow synthesis of single-subject experimental study results which is informative for evidence-based decision making, research and theory building, and policy discussions. We discuss different design matrices that can be used for the most common single-subject experimental designs (SSEDs), namely, the multiple-baseline designs, reversal designs, and alternating treatment designs, and provide empirical illustrations. The purpose of this article is to guide single-subject experimental data analysts interested in analyzing and meta-analyzing SSED data. © The Author(s) 2014.
2013-03-27
Research Office (W911NF-12-1-0023). Ab initio calculations have been performed to study the effects of solute atoms on the c/a ratio of magnesium alloys ... effects of alloying elements on the c/a ratio of magnesium were performed. The most commonly and extensively used alloying elements such as Al, Mn, and... Magnesium Alloy Design - Theoretical and Experimental Studies of the Influence of Alloying Elements on Deformation Twinning M.F. Horstemeyer
Vijn, Thomas W; Wollersheim, Hub; Faber, Marjan J; Fluit, Cornelia R M G; Kremer, Jan A M
2018-05-30
A common approach to enhance patient-centered care is training care professionals. Additional training of patients has been shown to significantly improve patient-centeredness of care. In this participatory design and evaluation study, patient education and medical education will be combined by co-creating a patient-centered and interprofessional training program, wherein patients, students and care professionals learn together to improve patient-centeredness of care. In the design phase, scientific literature regarding interventions and effects of student-run patient education will be synthesized in a scoping review. In addition, focus group studies will be performed on the preferences of patients, students, care professionals and education professionals regarding the structure and content of the training program. Subsequently, an intervention plan of the training program will be constructed by combining these building blocks. In the evaluation phase, patients with a chronic disease, that is rheumatoid arthritis, diabetes and hypertension, and patients with an oncologic condition, that is colonic cancer and breast cancer, will learn together with medical students, nursing students and care professionals in training program cycles of three months. Process and effect evaluation will be performed using the plan-do-study-act (PDSA) method to evaluate and optimize the training program in care practice and medical education. A modified control design will be used in PDSA-cycles to ensure that students who act as control will also benefit from participating in the program. Our participatory design and evaluation study provides an innovative approach in designing and evaluating an intervention by involving participants in all stages of the design and evaluation process. The approach is expected to enhance the effectiveness of the training program by assessing and meeting participants' needs and preferences. Moreover, by using fast PDSA cycles and a modified control design in evaluating the training program, the training program is expected to be efficiently and rapidly implemented into and adjusted to care practice and medical education.
The Study Review Process. WWC Process Brief
ERIC Educational Resources Information Center
What Works Clearinghouse, 2017
2017-01-01
Many studies of education interventions make claims about impacts on students' outcomes. Some studies have designs that enable readers to make causal inferences about the effects of an intervention but others have designs that do not permit these types of conclusions. To help policymakers, practitioners, and others make sense of study results, the…
Moazami, Fariborz; Bahrampour, Ehsan; Azar, Mohammad Reza; Jahedi, Farzad; Moattari, Marzieh
2014-03-05
The importance of using technologies such as e-learning in different disciplines is discussed in the literature. Researchers have measured the effectiveness of e-learning in a number of fields.Considering the lack of research on the effectiveness of online learning in dental education particularly in Iran, the advantages of these learning methods and the positive university atmosphere regarding the use of online learning. This study, therefore, aims to compare the effects of two methods of teaching (virtual versus traditional) on student learning. This post-test only design study approached 40, fifth year dental students of Shiraz University of Medical Sciences. From this group, 35 students agreed to participate. These students were randomly allocated into two groups, experimental (virtual learning) and comparison (traditional learning). To ensure similarity between groups, we compared GPAs of all participants by the Mann-Whitney U test (P > 0.05). The experimental group received a virtual learning environment courseware package specifically designed for this study, whereas the control group received the same module structured in a traditional lecture form. The virtual learning environment consisted of online and offline materials. Two identical valid, reliable post-tests that consisted of 40 multiple choice questions (MCQs) and 4 essay questions were administered immediately (15 min) after the last session and two months later to assess for knowledge retention. Data were analyzed by SPSS version 20. A comparison of the mean knowledge score of both groups showed that virtual learning was more effective than traditional learning (effect size = 0.69). The newly designed virtual learning package is feasible and will result in more effective learning in comparison with lecture-based training. However further studies are needed to generalize the findings of this study.
Are Water-Related Leadership Development Programs Designed to Be Effective? An Exploratory Study
ERIC Educational Resources Information Center
Burbach, Mark E.; Floress, Kristin; Kaufman, Eric K.
2015-01-01
Water resource professionals and others involved in managing water resources face increasingly complex challenges. Effective leadership development programs are needed to produce water leaders who can address these challenges. Leadership programs must be designed not simply to increase participants' environmental and leadership knowledge but to…
Explaining Relationships among Student Outcomes and the School's Physical Environment
ERIC Educational Resources Information Center
Tanner, C. Kenneth
2008-01-01
This descriptive study investigated the possible effects of selected school design patterns on third-grade students' academic achievement. A reduced regression analysis revealed the effects of school design components (patterns) on ITBS achievement data, after including control variables, for a sample of third-grade students drawn from 24…
Performance Outcomes of an Online First Aid and CPR Course for Laypersons
ERIC Educational Resources Information Center
Cason, Carolyn L.; Stiller, Janeth
2011-01-01
Objective: The study evaluated the effectiveness of an online first aid course by comparing it with the traditional instructor-led course. An effective online course increases course accessibility and mitigates the major deterrent to widespread layperson training. Design: A comparison group design evaluated performances among 25 laypersons…
Enhanced avatar design using cognitive map-based simulation.
Lee, Kun Chang; Moon, Byung Suk
2007-12-01
With the advent of the Internet era and the maturation of electronic commerce, strategic avatar design has become an important way of keeping up with market changes and customer tastes. In this study, we propose a new approach to an adaptive avatar design that uses cognitive map (CM) as a what-if simulation vehicle. The main virtue of the new design is its ability to change specific avatar design features with objective consideration of the subsequent effects upon other design features, thereby enhancing user satisfaction. Statistical analyses of focus group interview results with a group of experts majoring in avatars and CM showed that our proposed approach could be used to effectively analyze avatar design in an adaptive and practical manner when the market situation is changing.
Könings, Karen D; Brand-Gruwel, Saskia; Elen, Jan
2012-09-01
Students' perspective on education is of crucial importance for its effectivity, but students' opinions are seldom acknowledged by teachers and designers. Student participation in the educational design process could be a suitable tool to better take students' preferences into account. However, for effective participatory design, it is necessary to know whether students have stable preferences for the design of their education. Changeability of preferences would require a more continuing design process allowing continuous adaptations. This longitudinal survey study aimed to determine the changeability over time of students' preferences for different aspects of a learning environment. Additionally, causes of possible changes in preferences are investigated. The participants were 1,335 high school students of five schools for secondary education in the Netherlands, joining this study during a period of 2 years. Data about students' preferences were collected at three moments, using the Inventory of Perceived Study Environment Extended. Learning-related student characteristics, such as processing strategies and motivational orientations, were measured with the Inventory of Learning Styles. Additionally, data on learning performances were collected. The results showed stability on preferences for almost all studied characteristics of the learning environment. Particularly remarkable was a drop in desirability for student autonomy. This was larger for students with a certificate-oriented motivation and smaller for self-regulated students. Additionally, poorly performing students had a larger decrease in preference for autonomy. The stability on most aspects supports that participatory design might result in fairly stable instructional designs, although caution is needed with respect to student autonomy. ©2011 The British Psychological Society.
Lim, Megan S C; Wright, Cassandra J C; Carrotte, Elise R; Pedrana, Alisa E
2016-02-01
Issue addressed Social networking sites (SNS) are increasingly popular platforms for health promotion. Advancements in SNS health promotion require quality evidence; however, interventions are often not formally evaluated. This study aims to describe evaluation practices used in SNS health promotion. Methods A systematic review was undertaken of Medline, PsycINFO, Scopus, EMBASE, CINAHL Plus, Communication and Mass Media Complete, and Cochrane Library databases. Articles published between 2006 and 2013 describing any health promotion intervention delivered using SNS were included. Results Forty-seven studies were included. There were two main evaluation approaches: closed designs (n=23), which used traditional research designs and formal recruitment procedures; and open designs (n=19), which evaluated the intervention in a real-world setting, allowing unknown SNS users to interact with the content without enrolling in research. Closed designs were unable to assess reach and engagement beyond their research sample. Open designs often relied on weaker study designs with no use of objective outcome measures and yielded low response rates. Conclusions Barriers to evaluation included low participation rates, high attrition, unknown representativeness and lack of comparison groups. Acceptability was typically assessed among those engaged with the intervention, with limited population data available to accurately assess intervention reach. Few studies were able to assess uptake of the intervention in a real-life setting while simultaneously assessing effectiveness of interventions with research rigour. So what? Through use of quasi-experimental or well designed before-after evaluations, in combination with detailed engagement metrics, it is possible to balance assessment of effectiveness and reach to evaluate SNS health promotion.
ERIC Educational Resources Information Center
Peterson, Julie Ellen
2009-01-01
The first purpose of this experimental study was to determine if there were effects on achievement between traditional pencil-and-paper instructional strategies and computer simulated instructional strategies used to teach interior design business ethics. The second purpose was to determine the level of engagement of interior design students using…
ERIC Educational Resources Information Center
Denis Çeliker, Huriye
2015-01-01
The purpose of this study is to investigate the effect of designing problem-based experiments (DPBE) on the level of metacognitive skills of prospective science teachers. For this purpose, pre test-post test design, without control group, was used in the research. The research group of the study comprised 113 second-grade prospective science…
A Multiple Case Study of Faculty Control over Course Design and Its Effect on Faculty Efficacy
ERIC Educational Resources Information Center
King, Tara
2017-01-01
Online education continues to grow and change and different colleges and universities have varying degrees of faculty control over course design. This multiple case study investigated patterns in the efficacy of faculty who teach online courses in relation to the faculty members' involvement in the creation of elements of course design. The…
Pre-Service Physics Teachers' Views on Designing and Developing Physics Digital Stories
ERIC Educational Resources Information Center
Kocakaya, Serhat; Kotluk, Nihat; Karakoyun, Ferit
2016-01-01
The aim of this study is to determine the pre-service physics teachers' views on the effect of designing and developing physics digital stories (DST) on improving their 21st century skills. The study is a qualitative research carried out with 13 pre-service physics teachers, who participated in the course of designing and developing DST, during 6…
ERIC Educational Resources Information Center
Bertolli, Jeanne; And Others
1995-01-01
This article discusses methodologic limitations of four observational study designs (ecologic, case-control, cross-sectional, and cohort) that dominate the child abuse and neglect literature and identifies key features of an "ideal" study of child maltreatment. It proposes a new mixed-design strategy, which improves ability to identify child…
Austin, Peter C; Anderson, Geoffrey M; Cigsar, Candemir; Gruneir, Andrea
2012-01-01
Purpose Observational studies using electronic administrative healthcare databases are often used to estimate the effects of treatments and exposures. Traditionally, a cohort design has been used to estimate these effects, but increasingly, studies are using a nested case–control (NCC) design. The relative statistical efficiency of these two designs has not been examined in detail. Methods We used Monte Carlo simulations to compare these two designs in terms of the bias and precision of effect estimates. We examined three different settings: (A) treatment occurred at baseline, and there was a single outcome of interest; (B) treatment was time varying, and there was a single outcome; and C treatment occurred at baseline, and there was a secondary event that competed with the primary event of interest. Comparisons were made of percentage bias, length of 95% confidence interval, and mean squared error (MSE) as a combined measure of bias and precision. Results In Setting A, bias was similar between designs, but the cohort design was more precise and had a lower MSE in all scenarios. In Settings B and C, the cohort design was more precise and had a lower MSE in all scenarios. In both Settings B and C, the NCC design tended to result in estimates with greater bias compared with the cohort design. Conclusions We conclude that in a range of settings and scenarios, the cohort design is superior in terms of precision and MSE. Copyright © 2012 John Wiley & Sons, Ltd. PMID:22653805
Statistical inference for the additive hazards model under outcome-dependent sampling.
Yu, Jichang; Liu, Yanyan; Sandler, Dale P; Zhou, Haibo
2015-09-01
Cost-effective study design and proper inference procedures for data from such designs are always of particular interests to study investigators. In this article, we propose a biased sampling scheme, an outcome-dependent sampling (ODS) design for survival data with right censoring under the additive hazards model. We develop a weighted pseudo-score estimator for the regression parameters for the proposed design and derive the asymptotic properties of the proposed estimator. We also provide some suggestions for using the proposed method by evaluating the relative efficiency of the proposed method against simple random sampling design and derive the optimal allocation of the subsamples for the proposed design. Simulation studies show that the proposed ODS design is more powerful than other existing designs and the proposed estimator is more efficient than other estimators. We apply our method to analyze a cancer study conducted at NIEHS, the Cancer Incidence and Mortality of Uranium Miners Study, to study the risk of radon exposure to cancer.
Statistical inference for the additive hazards model under outcome-dependent sampling
Yu, Jichang; Liu, Yanyan; Sandler, Dale P.; Zhou, Haibo
2015-01-01
Cost-effective study design and proper inference procedures for data from such designs are always of particular interests to study investigators. In this article, we propose a biased sampling scheme, an outcome-dependent sampling (ODS) design for survival data with right censoring under the additive hazards model. We develop a weighted pseudo-score estimator for the regression parameters for the proposed design and derive the asymptotic properties of the proposed estimator. We also provide some suggestions for using the proposed method by evaluating the relative efficiency of the proposed method against simple random sampling design and derive the optimal allocation of the subsamples for the proposed design. Simulation studies show that the proposed ODS design is more powerful than other existing designs and the proposed estimator is more efficient than other estimators. We apply our method to analyze a cancer study conducted at NIEHS, the Cancer Incidence and Mortality of Uranium Miners Study, to study the risk of radon exposure to cancer. PMID:26379363
Federal Register 2010, 2011, 2012, 2013, 2014
2013-08-27
... improve the quality of this review. AHRQ is conducting this comparative effectiveness review pursuant to..., study period, design, methodology, indication and diagnosis, proper use instructions, inclusion and... including a study number, the study period, design, methodology, indication and diagnosis, proper use...
ERIC Educational Resources Information Center
Shadish, William R.
2011-01-01
This article reviews several decades of the author's meta-analytic and experimental research on the conditions under which nonrandomized experiments can approximate the results from randomized experiments (REs). Several studies make clear that we can expect accurate effect estimates from the regression discontinuity design, though its statistical…
Making intelligent systems team players: Additional case studies
NASA Technical Reports Server (NTRS)
Malin, Jane T.; Schreckenghost, Debra L.; Rhoads, Ron W.
1993-01-01
Observations from a case study of intelligent systems are reported as part of a multi-year interdisciplinary effort to provide guidance and assistance for designers of intelligent systems and their user interfaces. A series of studies were conducted to investigate issues in designing intelligent fault management systems in aerospace applications for effective human-computer interaction. The results of the initial study are documented in two NASA technical memoranda: TM 104738 Making Intelligent Systems Team Players: Case Studies and Design Issues, Volumes 1 and 2; and TM 104751, Making Intelligent Systems Team Players: Overview for Designers. The objective of this additional study was to broaden the investigation of human-computer interaction design issues beyond the focus on monitoring and fault detection in the initial study. The results of this second study are documented which is intended as a supplement to the original design guidance documents. These results should be of interest to designers of intelligent systems for use in real-time operations, and to researchers in the areas of human-computer interaction and artificial intelligence.
Kypri, Kypros; McCambridge, Jim; Wilson, Amanda; Attia, John; Sheeran, Paschal; Bowe, Steve; Vater, Tina
2011-02-14
What study participants think about the nature of a study has been hypothesised to affect subsequent behaviour and to potentially bias study findings. In this trial we examine the impact of awareness of study design and allocation on participant drinking behaviour. A three-arm parallel group randomised controlled trial design will be used. All recruitment, screening, randomisation, and follow-up will be conducted on-line among university students. Participants who indicate a hazardous level of alcohol consumption will be randomly assigned to one of three groups. Group A will be informed their drinking will be assessed at baseline and again in one month (as in a cohort study design). Group B will be told the study is an intervention trial and they are in the control group. Group C will be told the study is an intervention trial and they are in the intervention group. All will receive exactly the same brief educational material to read. After one month, alcohol intake for the past 4 weeks will be assessed. The experimental manipulations address subtle and previously unexplored ways in which participant behaviour may be unwittingly influenced by standard practice in trials. Given the necessity of relying on self-reported outcome, it will not be possible to distinguish true behaviour change from reporting artefact. This does not matter in the present study, as any effects of awareness of study design or allocation involve bias that is not well understood. There has been little research on awareness effects, and our outcomes will provide an indication of the possible value of further studies of this type and inform hypothesis generation. Australia and New Zealand Clinical Trials Register (ANZCTR): ACTRN12610000846022.
76 FR 32148 - Applications for New Awards; Investing in Innovation Fund
Federal Register 2010, 2011, 2012, 2013, 2014
2011-06-03
.... Interrupted time series design \\5\\ means a type of quasi- experimental study in which the outcome of interest... interrupted time series design that relies on the comparison of treatment effects on a single subject or group... matched comparison group designs (as defined in this notice), interrupted time series designs (as defined...
Power Analysis in Two-Level Unbalanced Designs
ERIC Educational Resources Information Center
Konstantopoulos, Spyros
2010-01-01
Previous work on statistical power has discussed mainly single-level designs or 2-level balanced designs with random effects. Although balanced experiments are common, in practice balance cannot always be achieved. Work on class size is one example of unbalanced designs. This study provides methods for power analysis in 2-level unbalanced designs…
Effects of School Design on Student Outcomes
ERIC Educational Resources Information Center
Tanner, C. Kenneth
2009-01-01
Purpose: The purpose of this study is to compare student achievement with three school design classifications: movement and circulation, day lighting, and views. Design/methodology/approach: From a sample of 71 schools, measures of these three school designs, taken with a ten-point Likert scale, are compared to students' outcomes defined by six…
Exploring Design Elements for Online STEM Courses: Active Learning, Engagement & Assessment Design
ERIC Educational Resources Information Center
Chen, Baiyun; Bastedo, Kathleen; Howard, Wendy
2018-01-01
The purpose of this study was to examine effective design elements for online courses in the science, technology, engineering, and mathematics (STEM) fields at a large four-year public university in southeastern United States. Our research questions addressed the influence of online design elements on students' perception of learning and learning…
Aeroelastic Optimization Study Based on X-56A Model
NASA Technical Reports Server (NTRS)
Li, Wesley; Pak, Chan-Gi
2014-01-01
A design process which incorporates the object-oriented multidisciplinary design, analysis, and optimization (MDAO) tool and the aeroelastic effects of high fidelity finite element models to characterize the design space was successfully developed and established. Two multidisciplinary design optimization studies using an object-oriented MDAO tool developed at NASA Armstrong Flight Research Center were presented. The first study demonstrates the use of aeroelastic tailoring concepts to minimize the structural weight while meeting the design requirements including strength, buckling, and flutter. A hybrid and discretization optimization approach was implemented to improve accuracy and computational efficiency of a global optimization algorithm. The second study presents a flutter mass balancing optimization study. The results provide guidance to modify the fabricated flexible wing design and move the design flutter speeds back into the flight envelope so that the original objective of X-56A flight test can be accomplished.
Usability engineering for augmented reality: employing user-based studies to inform design.
Gabbard, Joseph L; Swan, J Edward
2008-01-01
A major challenge, and thus opportunity, in the field of human-computer interaction and specifically usability engineering is designing effective user interfaces for emerging technologies that have no established design guidelines or interaction metaphors or introduce completely new ways for users to perceive and interact with technology and the world around them. Clearly, augmented reality is one such emerging technology. We propose a usability engineering approach that employs user-based studies to inform design, by iteratively inserting a series of user-based studies into a traditional usability engineering lifecycle to better inform initial user interface designs. We present an exemplar user-based study conducted to gain insight into how users perceive text in outdoor augmented reality settings and to derive implications for design in outdoor augmented reality. We also describe lessons learned from our experiences conducting user-based studies as part of the design process.
The effect of St John’s wort extracts on CYP3A: a systematic review of prospective clinical trials
Whitten, D L; Myers, S P; Hawrelak, J A; Wohlmuth, H
2006-01-01
Aim The aim of this systematic review was to assess the quality and outcomes of clinical trials investigating the effect of St John’s wort extracts on the metabolism of drugs by CYP3A. Methods Prospective clinical trials assessing the effect of St John’s wort (SJW) extracts on metabolism by CYP3A were identified through computer-based searches (from their inception to May 2005) of Medline, Cinahl, PsycINFO, AMED, Current Contents and Embase, hand-searches of bibliographies of relevant papers and consultation with manufacturers and researchers in the field. Two reviewers selected trials for inclusion, independently extracted data and recorded details on study design. Results Thirty-one studies met the eligibility criteria. More than two-thirds of the studies employed a before-and-after design, less than one-third of the studies used a crossover design, and only three studies were double-blind and placebo controlled. In 12 studies the SJW extract had been assayed, and 14 studies stated the specific SJW extract used. Results from 26 studies, including all of the 19 studies that used high-dose hyperforin extracts (>10 mg day−1), had outcomes consistent with CYP3A induction. The three studies using low-dose hyperforin extracts (<4 mg day−1) demonstrated no significant effect on CYP3A. Conclusion There is reasonable evidence to suggest that high-dose hyperforin SJW extracts induce CYP3A. More studies are required to determine whether decreased CYP3A induction occurs after low-dose hyperforin extracts. Future studies should adopt study designs with a control phase or control group, identify the specific SJW extract employed and provide quantitative analyses of key constituents. PMID:17010103
Dallas area rapid transit LRT starter line assessment study design. Final research report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shunk, G.A.; Turnbull, K.F.; Lindquist, N.F.
1995-03-01
Light rail transit (LRT) systems have recently been implemented in a number of urban areas throughout the United States and additional projects are in various stages of planning and development. Questions have been raised concerning the impact of these systems on ridership levels, transit operating costs, regional mobility, land use, economic development, energy, air quality, congestion levels, and other factors. The implementation of the Dallas Area Rapid Transit (DART) LRT starter line provides the opportunity to assess the impact of an LRT system in a Southwestern city in the United States. This research project was undertaken to assist with themore » development of a comprehensive study design for assessing the effects of the DART LRT starter line. To accomplish this objective, a review was conducted of before-and-after studies of recent LRT, heavy rail, and high-occupancy vehicle (HOV) projects. The goals and objectives of the DART system were also reviewed and existing transportation-related data collection activities in the Dallas area were examined. This information was used to develop a preliminary study design for assessing the effects of the DART LRT starter line. This report documents the review of recent before-and-after studies and presents the preliminary study design for assessing the effects of the DART LRT starter line.« less
An application of interactive computer graphics technology to the design of dispersal mechanisms
NASA Technical Reports Server (NTRS)
Richter, B. J.; Welch, B. H.
1977-01-01
Interactive computer graphics technology is combined with a general purpose mechanisms computer code to study the operational behavior of three guided bomb dispersal mechanism designs. These studies illustrate the use of computer graphics techniques to discover operational anomalies, to assess the effectiveness of design improvements, to reduce the time and cost of the modeling effort, and to provide the mechanism designer with a visual understanding of the physical operation of such systems.
Interventions to prevent youth violence in Latin America: a systematic review.
Atienzo, Erika E; Baxter, Susan K; Kaltenthaler, Eva
2017-01-01
This review aims to summarise evidence on the effectiveness of interventions to prevent youth violence in Latin America. A systematic search on 13 academic databases was conducted to locate studies evaluating a primary or secondary prevention intervention in Latin America. Studies could use any type of quantitative design to assess outcomes related to youth violence. A search of websites, references and citation searching was also carried out. The quality of each study was assessed. Nine studies were identified. Most documented positive effects of the interventions on the perception of youth violence present in the community/school. Evidence was found of a reduction in homicides and juvenile crimes in three studies, two of which evaluated a community-based intervention. There were mixed results for the self-report of participation on violent acts. The majority of the studies lacked of a rigorous design. Most of the interventions had some promising results, including the reduction of homicides within communities. Community-based programmes were the most consistent regarding an effectiveness to prevent violence. However, the evidence for Latin America is still scarce and relies on non-rigorously designed studies.
The Effects of General System Justification on Corruption Perception and Intent
Tan, Xuyun; Liu, Li; Huang, Zhenwei; Zheng, Wenwen; Liang, Yuan
2016-01-01
Previous research stresses that system justifying belief can weaken corruption perception, by this possibly fostering unjust behaviors. However, general results of the effect of general system justification on corruption are ambiguous, indicating also a lessening impact. We conducted a line of studies trying to elucidate these circumstances by testing the effect of general system justification on corruption perception and intention. In addition, we explored institutional trust as a possible mediator in this process. For this purpose, we conducted three studies. The first two studies examined the association between general system justification and corruption. In Study 1, a correlational design was run using questionnaires to assess the relation between general system justification and corruption perception as well as corruption intention. In Study 2, an experimental design was conducted manipulating general system justification via exposure to high or low system threat condition, then measuring its effect on corruption perception and corrupt intention. In Study 3, two sub-studies using correlational and experimental designs were run to explore the mediating role of institutional trust, respectively. Results replicated former studies showing that general system justification is negatively associated with corruption perception. However, they also showed a negative correlation with corrupt intention. Furthermore, they showed that institutional trust mediated the relation between general system justification and corruption. We suggest to consider these findings to further elucidate the psychological basis underlying different effects of general system justification on human behaviors. PMID:27507954
The Effects of General System Justification on Corruption Perception and Intent.
Tan, Xuyun; Liu, Li; Huang, Zhenwei; Zheng, Wenwen; Liang, Yuan
2016-01-01
Previous research stresses that system justifying belief can weaken corruption perception, by this possibly fostering unjust behaviors. However, general results of the effect of general system justification on corruption are ambiguous, indicating also a lessening impact. We conducted a line of studies trying to elucidate these circumstances by testing the effect of general system justification on corruption perception and intention. In addition, we explored institutional trust as a possible mediator in this process. For this purpose, we conducted three studies. The first two studies examined the association between general system justification and corruption. In Study 1, a correlational design was run using questionnaires to assess the relation between general system justification and corruption perception as well as corruption intention. In Study 2, an experimental design was conducted manipulating general system justification via exposure to high or low system threat condition, then measuring its effect on corruption perception and corrupt intention. In Study 3, two sub-studies using correlational and experimental designs were run to explore the mediating role of institutional trust, respectively. Results replicated former studies showing that general system justification is negatively associated with corruption perception. However, they also showed a negative correlation with corrupt intention. Furthermore, they showed that institutional trust mediated the relation between general system justification and corruption. We suggest to consider these findings to further elucidate the psychological basis underlying different effects of general system justification on human behaviors.
Koek, Mayke BG; Buskens, Erik; Steegmans, Paul HA; van Weelden, Huib; Bruijnzeel-Koomen, Carla AFM; Sigurdsson, Vigfús
2006-01-01
Background Home ultraviolet B (UVB) treatment is a much-debated treatment, especially with regard to effectiveness, safety and side effects. However, it is increasingly being prescribed, especially in the Netherlands. Despite ongoing discussions, no randomised research has been performed, and only two studies actually compare two groups of patients. Thus, firm evidence to support or discourage the use of home UVB phototherapy has not yet been obtained. This is the goal of the present study, the PLUTO study (Dutch acronym for "national trial on home UVB phototherapy for psoriasis"). Methods We designed a pragmatic randomised single-blind multi-centre trial. This trial is designed to evaluate the impact of home UVB treatment versus UVB phototherapy in a hospital outpatient clinic as to effectiveness, quality of life and cost-effectiveness. In total 196 patients with psoriasis who were clinically eligible for UVB phototherapy were included. Normally 85% of the patients treated with UVB show a relevant clinical response. With a power of 80% and a 0.05 significance level it will be possible to detect a reduction in effectiveness of 15%. Effectiveness will be determined by calculating differences in the Psoriasis Area and Severity Index (PASI) and the Self Administered PASI (SAPASI) scores. Quality of life is measured using several validated generic questionnaires and a disease-specific questionnaire. Other outcome measures include costs, side effects, dosimetry, concomitant use of medication and patient satisfaction. Patients are followed throughout the therapy and for 12 months thereafter. The study is no longer recruiting patients, and is expected to report in 2006. Discussion In the field of home UVB phototherapy this trial is the first randomised parallel group study. As such, this trial addresses the weaknesses encountered in previous studies. The pragmatic design ensures that the results can be well generalised to the target population. Because, in addition to effectiveness, aspects such as quality of life and cost-effectiveness are also taken into consideration, this study will produce valuable evidence to either support or discourage prescription of home UVB phototherapy. Trial registration Current controlled trials/Nederlands Trial register: ISRCTN83025173. Clinicaltrials.gov: NCT00150930 PMID:16882343
Koek, Mayke B G; Buskens, Erik; Steegmans, Paul H A; van Weelden, Huib; Bruijnzeel-Koomen, Carla A F M; Sigurdsson, Vigfús
2006-08-01
Home ultraviolet B (UVB) treatment is a much-debated treatment, especially with regard to effectiveness, safety and side effects. However, it is increasingly being prescribed, especially in the Netherlands. Despite ongoing discussions, no randomised research has been performed, and only two studies actually compare two groups of patients. Thus, firm evidence to support or discourage the use of home UVB phototherapy has not yet been obtained. This is the goal of the present study, the PLUTO study (Dutch acronym for "national trial on home UVB phototherapy for psoriasis"). We designed a pragmatic randomised single-blind multi-centre trial. This trial is designed to evaluate the impact of home UVB treatment versus UVB phototherapy in a hospital outpatient clinic as to effectiveness, quality of life and cost-effectiveness. In total 196 patients with psoriasis who were clinically eligible for UVB phototherapy were included. Normally 85% of the patients treated with UVB show a relevant clinical response. With a power of 80% and a 0.05 significance level it will be possible to detect a reduction in effectiveness of 15%. Effectiveness will be determined by calculating differences in the Psoriasis Area and Severity Index (PASI) and the Self Administered PASI (SAPASI) scores. Quality of life is measured using several validated generic questionnaires and a disease-specific questionnaire. Other outcome measures include costs, side effects, dosimetry, concomitant use of medication and patient satisfaction. Patients are followed throughout the therapy and for 12 months thereafter. The study is no longer recruiting patients, and is expected to report in 2006. In the field of home UVB phototherapy this trial is the first randomised parallel group study. As such, this trial addresses the weaknesses encountered in previous studies. The pragmatic design ensures that the results can be well generalised to the target population. Because, in addition to effectiveness, aspects such as quality of life and cost-effectiveness are also taken into consideration, this study will produce valuable evidence to either support or discourage prescription of home UVB phototherapy. Current controlled trials/Nederlands Trial register: ISRCTN83025173. Clinicaltrials.gov: NCT00150930.
Design and analysis of post-marketing research.
Zhou, Xiao-Hua Andrew; Yang, Wei
2013-07-01
A post-marketing study is an integral part of research that helps to ensure a favorable risk-benefit profile for approved drugs used in the market. Because most of post-marketing studies use observational designs, which are liable to confounding, estimation of the causal effect of a drug versus a comparative one is very challenging. This article focuses on methodological issues of importance in designing and analyzing studies to evaluate the safety of marketed drugs, especially marketed traditional Chinese medicine (TCM) products. Advantages and limitations of the current designs and analytic methods for postmarketing studies are discussed, and recommendations are given for improving the validity of postmarketing studies in TCM products.
Taking Word Clouds Apart: An Empirical Investigation of the Design Space for Keyword Summaries.
Felix, Cristian; Franconeri, Steven; Bertini, Enrico
2018-01-01
In this paper we present a set of four user studies aimed at exploring the visual design space of what we call keyword summaries: lists of words with associated quantitative values used to help people derive an intuition of what information a given document collection (or part of it) may contain. We seek to systematically study how different visual representations may affect people's performance in extracting information out of keyword summaries. To this purpose, we first create a design space of possible visual representations and compare the possible solutions in this design space through a variety of representative tasks and performance metrics. Other researchers have, in the past, studied some aspects of effectiveness with word clouds, however, the existing literature is somewhat scattered and do not seem to address the problem in a sufficiently systematic and holistic manner. The results of our studies showed a strong dependency on the tasks users are performing. In this paper we present details of our methodology, the results, as well as, guidelines on how to design effective keyword summaries based in our discoveries.
Multiple-Purpose Subsonic Naval Aircraft (MPSNA) Multiple Application Propfan Study (MAPS)
NASA Technical Reports Server (NTRS)
Winkeljohn, D. M.; Mayrand, C. H.
1986-01-01
A conceptual design study compared a selected propfan-powered aircraft to a turbofan-powered aircraft for multiple Navy carrier-based support missions in the 1995 timeframe. Conventional takeoff and landing (CTOL) propfan and turbofan-powered designs and short takeoff/vertical landing (STOVL) propfan-powered designs are presented. Ten support mission profiles were defined and the aircraft were sized to be able to perform all ten missions. Emphasis was placed on efficient high altitude loiter for Airborne Early Warning (AEW) and low altitude high speed capability for various offensive and tactical support missions. The results of the study show that the propfan-powered designs have lighter gross weights, lower fuel fractions, and equal or greater performance capability than the turbofan-powered designs. Various sensitives were developed in the study, including the effect of using single-rotation versus counter-rotation propfans and the effect of AEW loiter altitude on vehicle gross weight and empty weight. A propfan technology development plan was presented which illustrates that the development of key components can be achieved without accelerated schedules through the extension of current and planned government and civil propfan programs.
Initial Development and Pilot Study Design of Interactive Lecture Demonstrations for ASTRO 101
NASA Astrophysics Data System (ADS)
Schwortz, Andria C.; French, D. A; Gutierrez, Joseph V; Sanchez, Richard L; Slater, Timothy F.; Tatge, Coty
2014-06-01
Interactive lecture demonstrations (ILDs) have repeatedly shown to be effective tools for improving student achievement in the context of learning physics. As a first step toward systematic development of interactive lecture demonstrations in ASTRO 101, the introductory astronomy survey course, a systematic review of education research, describing educational computer simulations (ECSs) reveals that initial development requires a targeted study of how ASTRO 101 students respond to ECSs in the non-science majoring undergraduate lecture setting. In this project we have adopted the process by which ILDs were designed, pilot-tested, and successfully implemented in the context of physics teaching (Sokoloff & Thornton, 1997; Sokoloff & Thornton, 2004). We have designed the initial pilot-test set of ASTRO 101 ILD instructional materials relying heavily on ECSs. Both an instructor’s manual and a preliminary classroom-ready student workbook have been developed, and we are implementing a pilot study to explore their effectiveness in communicating scientific content, and the extent to which they might enhance students’ knowledge of and perception about astronomy and science in general. The study design uses a pre-/post-test quasi-experimental study design measuring students’ normalized gain scores, calculated as per Hake (1998) and Prather (2009), using a slightly modified version of S. Slater’s (2011) Test Of Astronomy STandards TOAST combined with other instruments. The results of this initial study will guide the iterative development of ASTRO 101 ILDs that are intended to both be effective at enhancing student achievement and easy for instructors to successfully implement.
Design of DNA pooling to allow incorporation of covariates in rare variants analysis.
Guan, Weihua; Li, Chun
2014-01-01
Rapid advances in next-generation sequencing technologies facilitate genetic association studies of an increasingly wide array of rare variants. To capture the rare or less common variants, a large number of individuals will be needed. However, the cost of a large scale study using whole genome or exome sequencing is still high. DNA pooling can serve as a cost-effective approach, but with a potential limitation that the identity of individual genomes would be lost and therefore individual characteristics and environmental factors could not be adjusted in association analysis, which may result in power loss and a biased estimate of genetic effect. For case-control studies, we propose a design strategy for pool creation and an analysis strategy that allows covariate adjustment, using multiple imputation technique. Simulations show that our approach can obtain reasonable estimate for genotypic effect with only slight loss of power compared to the much more expensive approach of sequencing individual genomes. Our design and analysis strategies enable more powerful and cost-effective sequencing studies of complex diseases, while allowing incorporation of covariate adjustment.
ERIC Educational Resources Information Center
Liao, Kun-Hsi
2017-01-01
Three-dimensional (3D) product design is an essential ability that students of subjects related to product design must acquire. The factors that affect designers' performance in 3D design are numerous, one of which is spatial abilities. Studies have reported that spatial abilities can be used to effectively predict people's performance in…
Padhi, Radhakant; Bhardhwaj, Jayender R
2009-06-01
An adaptive drug delivery design is presented in this paper using neural networks for effective treatment of infectious diseases. The generic mathematical model used describes the coupled evolution of concentration of pathogens, plasma cells, antibodies and a numerical value that indicates the relative characteristic of a damaged organ due to the disease under the influence of external drugs. From a system theoretic point of view, the external drugs can be interpreted as control inputs, which can be designed based on control theoretic concepts. In this study, assuming a set of nominal parameters in the mathematical model, first a nonlinear controller (drug administration) is designed based on the principle of dynamic inversion. This nominal drug administration plan was found to be effective in curing "nominal model patients" (patients whose immunological dynamics conform to the mathematical model used for the control design exactly. However, it was found to be ineffective in curing "realistic model patients" (patients whose immunological dynamics may have off-nominal parameter values and possibly unwanted inputs) in general. Hence, to make the drug delivery dosage design more effective for realistic model patients, a model-following adaptive control design is carried out next by taking the help of neural networks, that are trained online. Simulation studies indicate that the adaptive controller proposed in this paper holds promise in killing the invading pathogens and healing the damaged organ even in the presence of parameter uncertainties and continued pathogen attack. Note that the computational requirements for computing the control are very minimal and all associated computations (including the training of neural networks) can be carried out online. However it assumes that the required diagnosis process can be carried out at a sufficient faster rate so that all the states are available for control computation.
ERIC Educational Resources Information Center
Bonnet, Lauren Kravetz
2012-01-01
This single-subject research study was designed to examine the effects of point-of-view video modeling (POVM) on the symbolic play actions and play-associated language of four preschool students with autism. A multiple baseline design across participants was conducted in order to evaluate the effectiveness of using POVM as an intervention for…
Hua, Ying; Becker, Franklin; Wurmser, Teri; Bliss-Holtz, Jane; Hedges, Christine
2012-01-01
Studies investigating factors contributing to improved quality of care have found that effective team member communication is among the most critical and influential aspects in the delivery of quality care. Relatively little research has examined the role of the physical design of nursing units on communication patterns among care providers. Although the concept of decentralized unit design is intended to increase patient safety, reduce nurse fatigue, and control the noisy, chaotic, and crowded space associated with centralized nursing stations, until recently little attention has been paid to how such nursing unit designs affected communication patterns or other medical and organizational outcomes. Using a pre/post research design comparing more centralized or decentralized unit designs with a new multi-hub design, the aim of this study was to describe the relationship between the clinical spatial environment and its effect on communication patterns, nurse satisfaction, distance walked, organizational outcomes, patient safety, and patient satisfaction. Hospital institutional data indicated that patient satisfaction increased substantially. Few significant changes were found in communication patterns; no significant changes were found in nurse job satisfaction, patient falls, pressure ulcers, or organizational outcomes such as average length of stay or patient census.
Developing a cost effective rock bed thermal energy storage system: Design and modelling
NASA Astrophysics Data System (ADS)
Laubscher, Hendrik Frederik; von Backström, Theodor Willem; Dinter, Frank
2017-06-01
Thermal energy storage is an integral part of the drive for low cost of concentrated solar power (CSP). Storage of thermal energy enables CSP plants to provide base load power. Alternative, cheaper concepts for storing thermal energy have been conceptually proposed in previous studies. Using rocks as a storage medium and air as a heat transfer fluid, the proposed concept offers the potential of lower cost storage because of the abundance and affordability of rocks. A packed rock bed thermal energy storage (TES) concept is investigated and a design for an experimental rig is done. This paper describes the design and modelling of an experimental test facility for a cost effective packed rock bed thermal energy storage system. Cost effective, simplified designs for the different subsystems of an experimental setup are developed based on the availability of materials and equipment. Modelling of this design to predict the thermal performance of the TES system is covered in this study. If the concept under consideration proves to be successful, a design that is scalable and commercially viable can be proposed for further development of an industrial thermal energy storage system.
ERIC Educational Resources Information Center
Arnold, Jeffery E.
2010-01-01
The purpose of this study was to determine the effect of four different design layouts of the New York State elementary science learning standards on user processing time and preference. Three newly developed layouts contained the same information as the standards core curriculum. In this study, the layout of the core guide is referred to as Book.…
ERIC Educational Resources Information Center
Alodwan, Talal; Almosa, Mosaab
2018-01-01
The study aimed to assess the effectiveness of a computer program based on Analysis, Design, Development, Implementation and Evaluation (ADDIE) Model on the achievement of Ninth Graders' listening and Reading Comprehension Skills in English. The study sample comprised 70 ninth graders during the second semester of the academic year 2016/2017. The…
Effects of street canyon design on pedestrian thermal comfort in the hot-humid area of China.
Zhang, Yufeng; Du, Xiaohan; Shi, Yurong
2017-08-01
The design characteristics of street canyons were investigated in Guangzhou in the hot-humid area of China, and the effects of the design factors and their interactions on pedestrian thermal comfort were studied by numerical simulations. The ENVI-met V4.0 (BASIC) model was validated by field observations and used to simulate the micrometeorological conditions and the standard effective temperature (SET) at pedestrian level of the street canyons for a typical summer day of Guangzhou. The results show that the micrometeorological parameters of mean radiant temperature (MRT) and wind speed play key roles in pedestrian thermal comfort. Street orientation has the largest contribution on SET at pedestrian level, followed by aspect ratio and greenery, while surface albedo and interactions between factors have small contributions. The street canyons oriented southeast-northwest or with a higher aspect ratio provide more shade, higher wind speed, and better thermal comfort conditions for pedestrians. Compared with the east-west-oriented street canyons, the north-south-oriented street canyons have higher MRTs and worse pedestrian thermal comfort due to their wider building spacing along the street. The effects of greenery change with the road width and the time of the day. Street canyon design is recommended to improve pedestrian thermal comfort. This study provides a better understanding of the effects of street canyon design on pedestrian thermal comfort and is a useful guide on urban design for the hot-humid area of China.
U24 : heavy truck rollover characterization (phase C).
DOT National Transportation Integrated Search
2010-08-01
The effect of changes in the suspension of a cargo tank semitrailer on its roll stability was studied in experiments and modeling. Three configurations were considered: a typical design; a design with a wider track; and a design with wider track and ...
ELECTROFISHING IN BOATABLE RIVERS: DOES SAMPLING DESIGN AFFECT BIOASSESSMENT METRICS?
The accurate bioassessment of boatable rivers using fish assemblage data requires that a representative sample of the assemblage be collected. In this study, data were collected using an electrofishing design that permitted comparisons of the effects of designs and distances on ...
Metformin and the Risk of Cancer
Suissa, Samy; Azoulay, Laurent
2012-01-01
OBJECTIVE Time-related biases in observational studies of drug effects have been described extensively in different therapeutic areas but less so in diabetes. Immortal time bias, time-window bias, and time-lag bias all tend to greatly exaggerate the benefits observed with a drug. RESEARCH DESIGN AND METHODS These time-related biases are described and shown to be prominent in observational studies that have associated metformin with impressive reductions in the incidence of and mortality from cancer. As a consequence, metformin received much attention as a potential anticancer agent; these observational studies sparked the conduction of randomized, controlled trials of metformin as cancer treatment. However, the spectacular effects reported in these studies are compatible with time-related biases. RESULTS We found that 13 observational studies suffered from immortal time bias; 9 studies had not considered time-window bias, whereas other studies did not consider inherent time-lagging issues when comparing the first-line treatment metformin with second- or third-line treatments. These studies, subject to time-related biases that are avoidable with proper study design and data analysis, led to illusory extraordinarily significant effects, with reductions in cancer risk with metformin ranging from 20 to 94%. Three studies that avoided these biases reported no effect of metformin use on cancer incidence. CONCLUSIONS Although observational studies are important to better understand the effects of drugs, their proper design and analysis is essential to avoid major time-related biases. With respect to metformin, the scientific evidence of its potential beneficial effects on cancer would need to be reassessed critically before embarking on further long and expensive trials. PMID:23173135
Microrandomized trials: An experimental design for developing just-in-time adaptive interventions.
Klasnja, Predrag; Hekler, Eric B; Shiffman, Saul; Boruvka, Audrey; Almirall, Daniel; Tewari, Ambuj; Murphy, Susan A
2015-12-01
This article presents an experimental design, the microrandomized trial, developed to support optimization of just-in-time adaptive interventions (JITAIs). JITAIs are mHealth technologies that aim to deliver the right intervention components at the right times and locations to optimally support individuals' health behaviors. Microrandomized trials offer a way to optimize such interventions by enabling modeling of causal effects and time-varying effect moderation for individual intervention components within a JITAI. The article describes the microrandomized trial design, enumerates research questions that this experimental design can help answer, and provides an overview of the data analyses that can be used to assess the causal effects of studied intervention components and investigate time-varying moderation of those effects. Microrandomized trials enable causal modeling of proximal effects of the randomized intervention components and assessment of time-varying moderation of those effects. Microrandomized trials can help researchers understand whether their interventions are having intended effects, when and for whom they are effective, and what factors moderate the interventions' effects, enabling creation of more effective JITAIs. (PsycINFO Database Record (c) 2015 APA, all rights reserved).
Micro-Randomized Trials: An Experimental Design for Developing Just-in-Time Adaptive Interventions
Klasnja, Predrag; Hekler, Eric B.; Shiffman, Saul; Boruvka, Audrey; Almirall, Daniel; Tewari, Ambuj; Murphy, Susan A.
2015-01-01
Objective This paper presents an experimental design, the micro-randomized trial, developed to support optimization of just-in-time adaptive interventions (JITAIs). JITAIs are mHealth technologies that aim to deliver the right intervention components at the right times and locations to optimally support individuals’ health behaviors. Micro-randomized trials offer a way to optimize such interventions by enabling modeling of causal effects and time-varying effect moderation for individual intervention components within a JITAI. Methods The paper describes the micro-randomized trial design, enumerates research questions that this experimental design can help answer, and provides an overview of the data analyses that can be used to assess the causal effects of studied intervention components and investigate time-varying moderation of those effects. Results Micro-randomized trials enable causal modeling of proximal effects of the randomized intervention components and assessment of time-varying moderation of those effects. Conclusions Micro-randomized trials can help researchers understand whether their interventions are having intended effects, when and for whom they are effective, and what factors moderate the interventions’ effects, enabling creation of more effective JITAIs. PMID:26651463
Studying Educational Effectiveness in Rural Settings: A Guide for Researchers
ERIC Educational Resources Information Center
Sheridan, Susan; Dynarski, Mark; Bovaird, James
2017-01-01
This guide provides experienced education researchers with suggestions for conducting high-quality effectiveness studies to overcome research challenges common to rural settings. The guide addresses four factors that researchers must consider when conducting educational effectiveness research in rural settings: (1) study design, (2) recruitment of…
de Hoop, Esther; van der Tweel, Ingeborg; van der Graaf, Rieke; Moons, Karel G M; van Delden, Johannes J M; Reitsma, Johannes B; Koffijberg, Hendrik
2015-10-30
Various papers have addressed pros and cons of the stepped wedge cluster randomized trial design (SWD). However, some issues have not or only limitedly been addressed. Our aim was to provide a comprehensive overview of all merits and limitations of the SWD to assist researchers, reviewers and medical ethics committees when deciding on the appropriateness of the SWD for a particular study. We performed an initial search to identify articles with a methodological focus on the SWD, and categorized and discussed all reported advantages and disadvantages of the SWD. Additional aspects were identified during multidisciplinary meetings in which ethicists, biostatisticians, clinical epidemiologists and health economists participated. All aspects of the SWD were compared to the parallel group cluster randomized design. We categorized the merits and limitations of the SWD to distinct phases in the design and conduct of such studies, highlighting that their impact may vary depending on the context of the study or that benefits may be offset by drawbacks across study phases. Furthermore, a real-life illustration is provided. New aspects are identified within all disciplines. Examples of newly identified aspects of an SWD are: the possibility to measure a treatment effect in each cluster to examine the (in)consistency in effects across clusters, the detrimental effect of lower than expected inclusion rates, deviation from the ordinary informed consent process and the question whether studies using the SWD are likely to have sufficient social value. Discussions are provided on e.g. clinical equipoise, social value, health economical decision making, number of study arms, and interim analyses. Deciding on the use of the SWD involves aspects and considerations from different disciplines not all of which have been discussed before. Pros and cons of this design should be balanced in comparison to other feasible design options as to choose the optimal design for a particular intervention study.
Designing Studies to Test Causal Questions About Early Math: The Development of Making Pre-K Count.
Mattera, Shira K; Morris, Pamela A; Jacob, Robin; Maier, Michelle; Rojas, Natalia
2017-01-01
A growing literature has demonstrated that early math skills are associated with later outcomes for children. This research has generated interest in improving children's early math competencies as a pathway to improved outcomes for children in elementary school. The Making Pre-K Count study was designed to test the effects of an early math intervention for preschoolers. Its design was unique in that, in addition to causally testing the effects of early math skills, it also allowed for the examination of a number of additional questions about scale-up, the influence of contextual factors and the counterfactual environment, the mechanism of long-term fade-out, and the role of measurement in early childhood intervention findings. This chapter outlines some of the design considerations and decisions put in place to create a rigorous test of the causal effects of early math skills that is also able to answer these questions in early childhood mathematics and intervention. The study serves as a potential model for how to advance science in the fields of preschool intervention and early mathematics. © 2017 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Arnold, William R.; Stahl, H. Philip
2017-09-01
An extensive trade study was conducted to evaluate primary mirror substrate design architectures for the HabEx mission baseline 4-meter off-axis telescope. The study's purpose is not to produce a final design, but rather to established a design methodology for matching the mirror's properties (mass and stiffness) with the mission's optical performance specifications (static dynamic wavefront error, WFE). The study systematically compares the effect of proven design elements (closed-back vs open-back vs partial-back; meniscus vs flat back vs shaped back; etc.), which can be implemented with proven space mirror materials (ULE and Zerodur), on static and dynamic WFE. Additionally, the study compares static and dynamic WFE of each substrate point design integrated onto three and six point mounts.
Haines, Terry; O'Brien, Lisa; McDermott, Fiona; Markham, Donna; Mitchell, Deb; Watterson, Dina; Skinner, Elizabeth
2014-02-01
Disinvestment is critical for ensuring the long-term sustainability of health-care services. Key barriers to disinvestment are heterogeneity between research and clinical settings, absence of evidence of effectiveness of some health technologies, and exposure of patients and organizations to risks and poor outcomes. We aimed to develop a feasible research design that can evaluate disinvestment in health technologies of uncertain effectiveness or cost-effectiveness. This article (1) establishes the need for disinvestment methodologies, (2) identifies the ethical concerns and feasibility constraints of conventional research designs for this issue, (3) describes the planning, implementation, and analytical framework for a novel disinvestment-specific study design, and (4) describes potential limitations in application of this design. The stepped-wedge, roll-in cluster randomized controlled trial can facilitate the disinvestment process, whereas generating evidence to determine whether the decision to disinvest was sound in the clinical environment. A noninferiority research paradigm may be applied to this methodology to demonstrate that the removal of a health technology does not adversely affect outcomes. This research design can be applied across multiple fields and will assist determination of whether specific health technologies are clinically effective, cost-effective, and safe. Copyright © 2014 Elsevier Inc. All rights reserved.
Split-mouth design in Paediatric Dentistry clinical trials.
Pozos-Guillén, A; Chavarría-Bolaños, D; Garrocho-Rangel, A
2017-03-01
The aim of this article was to describe the essential concepts of the split-mouth design, its underlying assumptions, advantages, limitations, statistical considerations, and possible applications in Paediatric Dentistry clinical investigation. In Paediatric Dentistry clinical investigation, and as part of randomised controlled trials, the split-mouth design is commonly used. The design is characterised by subdividing the child's dentition into halves (right and left), where two different treatment modalities are assigned to one side randomly, in order to allow further outcome evaluation. Each participant acts as their own control by making within- patient rather than between-patient comparisons, thus diminishing inter-subject variability and increasing study accuracy and power. However, the main problem with this design comprises the potential contamination of the treatment effect from one side to the other, or the "carry-across effect"; likewise, this design is not indicated when the oral disease to be treated is not symmetrically distributed (e.g. severity) in the mouth of children. Thus, in spite of its advantages, the split-mouth design can only be applied in a limited number of strictly selected cases. In order to obtain valid and reliable data from split mouth design studies, it is necessary to evaluate the risk of carry-across effect as well as to carefully analise and select adequate inclusion criteria, sample-size calculation and method of statistical analysis.
Huang, Jun; Goolcharran, Chimanlall; Ghosh, Krishnendu
2011-05-01
This paper presents the use of experimental design, optimization and multivariate techniques to investigate root-cause of tablet dissolution shift (slow-down) upon stability and develop control strategies for a drug product during formulation and process development. The effectiveness and usefulness of these methodologies were demonstrated through two application examples. In both applications, dissolution slow-down was observed during a 4-week accelerated stability test under 51°C/75%RH storage condition. In Application I, an experimental design was carried out to evaluate the interactions and effects of the design factors on critical quality attribute (CQA) of dissolution upon stability. The design space was studied by design of experiment (DOE) and multivariate analysis to ensure desired dissolution profile and minimal dissolution shift upon stability. Multivariate techniques, such as multi-way principal component analysis (MPCA) of the entire dissolution profiles upon stability, were performed to reveal batch relationships and to evaluate the impact of design factors on dissolution. In Application II, an experiment was conducted to study the impact of varying tablet breaking force on dissolution upon stability utilizing MPCA. It was demonstrated that the use of multivariate methods, defined as Quality by Design (QbD) principles and tools in ICH-Q8 guidance, provides an effective means to achieve a greater understanding of tablet dissolution upon stability. Copyright © 2010 Elsevier B.V. All rights reserved.
ERIC Educational Resources Information Center
Friedmann, Peter D.; Katz, Elizabeth C.; Rhodes, Anne G.; Taxman, Faye S.; O'Connell, Daniel J.; Frisman, Linda K.; Burdon, William M.; Fletcher, Bennett W.; Litt, Mark D.; Clarke, Jennifer; Martin, Steven S.
2008-01-01
This article describes the rationale, study design, and implementation for the Step'n Out study of the Criminal Justice Drug Abuse Treatment Studies. Step'n Out tests the relative effectiveness of collaborative behavioral management of drug-involved parolees. Collaborative behavioral management integrates the roles of parole officers and treatment…
Kalantari, Saleh; Snell, Robin
2017-07-01
This study was a post-occupancy evaluation (POE) to examine the effectiveness of three specific design innovations in a mental healthcare facility. In addition to collecting data about the impact of these specific designs, the study provides a model for the broader implementation of POE approaches in the mental healthcare context. POEs in general healthcare settings have been shown to lead to better work environments and better outcomes for patients. Despite growing evidence of the value provided by POE studies, the industry has been somewhat slow to adopt their regular use, in part due to unfamiliarity with the POE process. This is particularly true in mental healthcare contexts, where POE studies remain virtually nonexistent. In-depth interviews and a widely distributed, anonymous survey were used to collect hospital staff perceptions and feedback regarding the impact of specific design features. The hospital staff were quite enthusiastic about two of the design innovations studied here (a new wayfinding strategy and the use of vibrant colors in specific areas of the facility). The third innovation, open-style communication centers, elicited more mixed evaluations. The results include extensive hypothesis testing about the effects of each innovation as well as narrative discussions of their pros and cons. The study generated new knowledge about three specific mental healthcare design innovations and provides a model for the practical implementation of a POE approach in mental healthcare contexts. The results are particularly relevant for designers who are considering innovative strategies in future mental healthcare facilities.
Adult asthma disease management: an analysis of studies, approaches, outcomes, and methods.
Maciejewski, Matthew L; Chen, Shih-Yin; Au, David H
2009-07-01
Disease management has been implemented for patients with asthma in various ways. We describe the approaches to and components of adult asthma disease-management interventions, examine the outcomes evaluated, and assess the quality of published studies. We searched the MEDLINE, EMBASE, CINAHL, PsychInfo, and Cochrane databases for studies published in 1986 through 2008, on adult asthma management. With the studies that met our inclusion criteria, we examined the clinical, process, medication, economic, and patient-reported outcomes reported, and the study designs, provider collaboration during the studies, and statistical methods. Twenty-nine articles describing 27 studies satisfied our inclusion criteria. There was great variation in the content, extent of collaboration between physician and non-physician providers responsible for intervention delivery, and outcomes examined across the 27 studies. Because of limitations in the design of 22 of the 27 studies, the differences in outcomes assessed, and the lack of rigorous statistical adjustment, we could not draw definitive conclusions about the effectiveness or cost-effectiveness of the asthma disease-management programs or which approach was most effective. Few well-designed studies with rigorous evaluations have been conducted to evaluate disease-management interventions for adults with asthma. Current evidence is insufficient to recommend any particular intervention.
A probabilistic methodology for radar cross section prediction in conceptual aircraft design
NASA Astrophysics Data System (ADS)
Hines, Nathan Robert
System effectiveness has increasingly become the prime metric for the evaluation of military aircraft. As such, it is the decision maker's/designer's goal to maximize system effectiveness. Industry and government research documents indicate that all future military aircraft will incorporate signature reduction as an attempt to improve system effectiveness and reduce the cost of attrition. Today's operating environments demand low observable aircraft which are able to reliably take out valuable, time critical targets. Thus it is desirable to be able to design vehicles that are balanced for increased effectiveness. Previous studies have shown that shaping of the vehicle is one of the most important contributors to radar cross section, a measure of radar signature, and must be considered from the very beginning of the design process. Radar cross section estimation should be incorporated into conceptual design to develop more capable systems. This research strives to meet these needs by developing a conceptual design tool that predicts radar cross section for parametric geometries. This tool predicts the absolute radar cross section of the vehicle as well as the impact of geometry changes, allowing for the simultaneous tradeoff of the aerodynamic, performance, and cost characteristics of the vehicle with the radar cross section. Furthermore, this tool can be linked to a campaign theater analysis code to demonstrate the changes in system and system of system effectiveness due to changes in aircraft geometry. A general methodology was developed and implemented and sample computer codes applied to prototype the proposed process. Studies utilizing this radar cross section tool were subsequently performed to demonstrate the capabilities of this method and show the impact that various inputs have on the outputs of these models. The F/A-18 aircraft configuration was chosen as a case study vehicle to perform a design space exercise and to investigate the relative impact of shaping parameters on radar cross section. Finally, two unique low observable configurations were analyzed to examine the impact of shaping for stealthiness.
Evidence for the impact of quality improvement collaboratives: systematic review
2008-01-01
Objective To evaluate the effectiveness of quality improvement collaboratives in improving the quality of care. Data sources Relevant studies through Medline, Embase, PsycINFO, CINAHL, and Cochrane databases. Study selection Two reviewers independently extracted data on topics, participants, setting, study design, and outcomes. Data synthesis Of 1104 articles identified, 72 were included in the study. Twelve reports representing nine studies (including two randomised controlled trials) used a controlled design to measure the effects of the quality improvement collaborative intervention on care processes or outcomes of care. Systematic review of these nine studies showed moderate positive results. Seven studies (including one randomised controlled trial) reported an effect on some of the selected outcome measures. Two studies (including one randomised controlled trial) did not show any significant effect. Conclusions The evidence underlying quality improvement collaboratives is positive but limited and the effects cannot be predicted with great certainty. Considering that quality improvement collaboratives seem to play a key part in current strategies focused on accelerating improvement, but may have only modest effects on outcomes at best, further knowledge of the basic components effectiveness, cost effectiveness, and success factors is crucial to determine the value of quality improvement collaboratives. PMID:18577559
The Design and Development of an Online, Case-Based Course in a Teacher Preparation Program
ERIC Educational Resources Information Center
Peña, Carmen M.
2004-01-01
The goals of this study were to: 1) design a web-based course using WebCT for future secondary school teachers at the University of Texas Pan American, 2) evaluate the effectiveness of the course, and 3) provide a set of guidelines for designing web-based courses for other teacher educators. The participants in this study consisted of junior- and…
IETM Usability: Using Empirical Studies to Improve Performance Aiding
2001-05-14
is highly graphical . An example screen is shown in Figure 3. Following is a description of the design solutions incorporated in Interface B to...in enabling lesser skilled U.S. Navy maintainers to perform their jobs. This empirical study about the design and effectiveness of high level IETMs...novice preferences and performance were documented to inform future adaptive interface design efforts. The maintainers who participated were
ERIC Educational Resources Information Center
Evens, Marie; Larmuseau, Charlotte; Dewaele, Katrien; Van Craesbeek, Leen; Elen, Jan; Depaepe, Fien
2017-01-01
This study examines the effects of an online learning environment on preservice teachers' pedagogical content knowledge (PCK), content knowledge (CK) (related to French in primary teacher education), and pedagogical knowledge (PK) in a quasi-experimental design. More specifically, the following research question is addressed: Is a systematically…
Cost Effectiveness Analysis between Boarding and Day Secondary Students in Kenya
ERIC Educational Resources Information Center
Jagero, N.; Ayodo, T. M.; Agak, J. A.
2011-01-01
This paper examines the cost effectiveness of educating boarding and day secondary students in Kisumu district in Kenya. The research designs used in this study were descriptive survey and casual comparative designs. The population consisted of five head teachers, 140 form four teachers and 609 form four students. Saturated and systematic random…
ERIC Educational Resources Information Center
Nkemdilim, Egbunonu Roseline; Okeke, Sam O. C.
2014-01-01
This study investigated the effects of computer-assisted instruction (CAI) on students' achievement in ecological concepts. Quasi-experimental design, specifically the pre-test post test non-equivalent control group design was adopted. The sample consisted of sixty-six (66) senior secondary year two (SS II) biology students, drawn from two…
Effect Size Measure and Analysis of Single Subject Designs
ERIC Educational Resources Information Center
Swaminathan, Hariharan; Horner, Robert H.; Rogers, H. Jane; Sugai, George
2012-01-01
This study is aimed at addressing the criticisms that have been leveled at the currently available statistical procedures for analyzing single subject designs (SSD). One of the vexing problems in the analysis of SSD is in the assessment of the effect of intervention. Serial dependence notwithstanding, the linear model approach that has been…
Nudging Waste Diversion at Western State Colorado University: Application of Behavioral Insights
ERIC Educational Resources Information Center
McCoy, Kimberly; Oliver, Justin J.; Borden, D. Scott; Cohn, Scott I.
2018-01-01
Purpose: This paper aims to test a nudge, or intervention, designed through behavioral insights at a university campus to discover cost-effective means for increasing recycling participation and methods for estimating waste removal cost savings. Design/methodology/approach: A series of studies were conducted demonstrating the effectiveness of…
Effective Practice in the Design of Directed Independent Learning Opportunities
ERIC Educational Resources Information Center
Thomas, Liz; Jones, Robert; Ottaway, James
2015-01-01
This study, commissioned by the HEA and the QAA focuses on directed independent learning practices in UK higher education. It investigates what stakeholders (including academic staff and students) have found to be the most effective practices in the inception, design, quality assurance and enhancement of directed independent learning and explores…
The Effect of Amount and Timing of Human Resources Data on Subsystem Design.
ERIC Educational Resources Information Center
Meister, David; And Others
Human resources data (HRD) inputs often fail to influence system development. This study investigated the possibility that these inputs are sometimes deficient in quantity or timing. In addition, the effect upon design of different personnel quality and quantity requirements was analyzed. Equipment and HRD inputs which were produced during actual…
In 1999, the effect of electrofishing design (single bank or paired banks) and sampling distance on bioassessment results was studied in four boatable rivers in the Ohio River basin. The relationship between the number of species collected and the total distance electrofished wa...
ERIC Educational Resources Information Center
Fedewa, Alicia L.; Ahn, Soyeon; Erwin, Heather; Davis, Matthew C.
2015-01-01
Existing literature shows promising effects of physical activity on children's cognitive outcomes. This study assessed via a randomized, controlled design whether additional curricular physical activity during the school day resulted in gains for children's fluid intelligence and standardized achievement outcomes. Participants were children…
ERIC Educational Resources Information Center
Onu, V. C.; Eskay, M.; Igbo, J. N.; Obiyo, N.; Agbo, O.
2012-01-01
This study examined the effect of training in math metacognition on fractional mathematics among primary school pupils, with a quasi-experimental design, specifically a post-test only control group design. Two intact classes were randomly selected and assigned to treatment and control conditions. Sixty primary six pupils constituted the sample…
Advertising Graphic Design and Its Effect on Recall and Attitude: A Field Experiment.
ERIC Educational Resources Information Center
Surlin, Stuart H.; Kosak, Hermann H.
Advertisers and other mass media communicators are interested in the potential cognitive and affective effects of various graphic designs, specifically relating to the recall of information and the attitude toward information presented. This study deals with the respondent's recall of information contained within an advertisement as well as the…
ERIC Educational Resources Information Center
Baukal, Charles E.; Ausburn, Lynna J.
2017-01-01
Continuing engineering education (CEE) is important to ensure engineers maintain proficiency over the life of their careers. However, relatively few studies have examined designing effective training for working engineers. Research has indicated that both learner instructional preferences and prior knowledge can impact the learning process, but it…
ERIC Educational Resources Information Center
Kelcey, Benjamin; Dong, Nianbo; Spybrook, Jessaca; Cox, Kyle
2017-01-01
Designs that facilitate inferences concerning both the total and indirect effects of a treatment potentially offer a more holistic description of interventions because they can complement "what works" questions with the comprehensive study of the causal connections implied by substantive theories. Mapping the sensitivity of designs to…
Comparing the Effects of Home versus Clinic-Based Parent Training for Children with Autism
ERIC Educational Resources Information Center
Crone, Regina M.
2010-01-01
Research with parents on managing child problem behavior typically measures either child or parent behavior. This study was designed to evaluate the effectiveness of training parents to implement a function-based behavior intervention plan (BIP) in a non-trained natural environment utilizing a Multiple Probe Design across Participants.…
Letizia, M C; Cornaglia, M; Tranchida, G; Trouillon, R; Gijs, M A M
2018-01-22
When studying the drug effectiveness towards a target model, one should distinguish the effects of the drug itself and of all the other factors that could influence the screening outcome. This comprehensive knowledge is crucial, especially when model organisms are used to study the drug effect at a systemic level, as a higher number of factors can influence the drug-testing outcome. Covering the entire experimental domain and studying the effect of the simultaneous change in several factors would require numerous experiments, which are costly and time-consuming. Therefore, a design of experiment (DoE) approach in drug-testing is emerging as a robust and efficient method to reduce the use of resources, while maximizing the knowledge of the process. Here, we used a 3-factor-Doehlert DoE to characterize the concentration-dependent effect of the drug doxycycline on the development duration of the nematode Caenorhabditis elegans. To cover the experimental space, 13 experiments were designed and performed, where different doxycycline concentrations were tested, while also varying the temperature and the food amount, which are known to influence the duration of C. elegans development. A microfluidic platform was designed to isolate and culture C. elegans larvae, while testing the doxycycline effect with full control of temperature and feeding over the entire development. Our approach allowed predicting the doxycycline effect on C. elegans development in the complete drug concentration/temperature/feeding experimental space, maximizing the understanding of the effect of this antibiotic on the C. elegans development and paving the way towards a standardized and optimized drug-testing process.
Solomon design analysis of multiple-choice Rorschach animal content.
Feigenbaum, D; Costello, R M
1975-10-01
The Solomon four-group design was used to study the effects of a persuasive message on a selected multiple-choice Rorschach index--animal content. The independent variable elicited behavior in a predictable manner. Pretesting as a main effect was not significant, but as an interactional effect obviated the effect of the persuasive message. Although knowledge of test rationale can elicit behavior that conforms to experimental demand characteristics, some subjects nonetheless acted in defiance of such information. A condition for defiance in this experimental arrangement, however, was pretesting. Other possibilities regarding the study of compliance behavior and the use of pathognomonic indicators were suggested. Ethical issues were raised.
Mohamed, Somaia; Johnson, Gary R; Vertrees, Julia E; Guarino, Peter D; Weingart, Kimberly; Young, Ilanit Tal; Yoon, Jean; Gleason, Theresa C; Kirkwood, Katherine A; Kilbourne, Amy M; Gerrity, Martha; Marder, Stephen; Biswas, Kousick; Hicks, Paul; Davis, Lori L; Chen, Peijun; Kelada, AlexandraMary; Huang, Grant D; Lawrence, David D; LeGwin, Mary; Zisook, Sidney
2015-10-30
Because two-thirds of patients with Major Depressive Disorder do not achieve remission with their first antidepressant, we designed a trial of three "next-step" strategies: switching to another antidepressant (bupropion-SR) or augmenting the current antidepressant with either another antidepressant (bupropion-SR) or with an atypical antipsychotic (aripiprazole). The study will compare 12-week remission rates and, among those who have at least a partial response, relapse rates for up to 6 months of additional treatment. We review seven key efficacy/effectiveness design decisions in this mixed "efficacy-effectiveness" trial. Copyright © 2015. Published by Elsevier Ireland Ltd.
Sexual health education interventions for young people: a methodological review.
Oakley, A.; Fullerton, D.; Holland, J.; Arnold, S.; France-Dawson, M.; Kelley, P.; McGrellis, S.
1995-01-01
OBJECTIVES--To locate reports of sexual health education interventions for young people, assess the methodological quality of evaluations, identify the subgroup with a methodologically sound design, and assess the evidence with respect to the effectiveness of different approaches to promoting young people's sexual health. DESIGN--Survey of reports in English by means of electronic databases and hand searches for relevant studies conducted in the developed world since 1982. Papers were reviewed for eight methodological qualities. The evidence on effectiveness generated by studies meeting four core criteria was assessed. Judgments on effectiveness by reviewers and authors were compared. PAPERS--270 papers reporting sexual health interventions. MAIN OUTCOME MEASURE--The methodological quality of evaluations. RESULTS--73 reports of evaluations of sexual health interventions examining the effectiveness of these interventions in changing knowledge, attitudes, or behavioural outcomes were identified, of which 65 were separate outcome evaluations. Of these studies, 45 (69%) lacked random control groups, 44 (68%) failed to present preintervention and 38 (59%) postintervention data, and 26 (40%) omitted to discuss the relevance of loss of data caused by drop outs. Only 12 (18%) of the 65 outcome evaluations were judged to be methodologically sound. Academic reviewers were more likely than authors to judge studies as unclear because of design faults. Only two of the sound evaluations recorded interventions which were effective in showing an impact on young people's sexual behaviour. CONCLUSIONS--The design of evaluations in sexual health intervention needs to be improved so that reliable evidence of the effectiveness of different approaches to promoting young people's sexual health may be generated. PMID:7833754
School Effectiveness in the Dominican Republic.
ERIC Educational Resources Information Center
British Columbia Univ., Vancouver. Faculty of Education.
Characteristics distinguishing more effective from less effective public primary (grades 1 to 8) schools in Santo Domingo were studied, using a comparative case study design. The effectiveness of the school was determined by expert nomination and achievement tests in reading, mathematics, and writing. Socioeconomic status was controlled and three…
Energy absorption in aluminum extrusions for a spaceframe chassis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Logan, R.W.; Perfect, S.A.; Parkinson, R.D.
1994-09-19
This work describes the design, finite-element analysis, and verifications performed by LLNL and Kaiser Aluminum for the prototype design of the CALSTART Running Chassis purpose-built electric vehicle. Component level studies, along with our previous experimental and finite-element works, provided the confidence to study the crashworthiness of a complete aluminum spaceframe. Effects of rail geometry, size, and thickness were studied in order to achieve a controlled crush of the front end structure. These included the performance of the spaceframe itself, and the additive effects of the powertrain cradle and powertrain (motor/controller in this case) as well as suspension. Various design iterationsmore » for frontal impact at moderate and high speed are explored.« less
Dodge, Tonya; Litt, Dana; Kaufman, Annette
2011-03-01
The authors conducted two studies to examine the influence of the U.S. Dietary Supplement Health and Education Act (DSHEA) on consumer beliefs about the safety and effectiveness of dietary supplements. Study 1 manipulated information about Food and Drug Administration (FDA) approval in the context of a dietary supplement designed to improve immune system functioning. Study 2 tested the effect of an educational intervention designed to improve knowledge about the DSHEA. Results of Study 1 highlighted deficits in consumer knowledge about FDA regulation of dietary supplements. Results also showed that information about FDA approval failed to have a statistically significant effect on beliefs about safety or effectiveness of the dietary supplement. Results of Study 2 showed that participants who were educated about the regulation of dietary supplements under the DSHEA rated dietary supplements as less safe and less effective than did participants in the control condition. The authors discuss the implications for consumers in the United States and for public policy.
The Effect of STEM Learning through the Project of Designing Boat Model toward Student STEM Literacy
NASA Astrophysics Data System (ADS)
Tati, T.; Firman, H.; Riandi, R.
2017-09-01
STEM Learning focusses on development of STEM-literate society, the research about implementation of STEM learning to develope students’ STEM literacy is still limited. This study is aimed to examine the effect of implementation STEM learning through the project of designing boat model on students STEM literacy in energy topic. The method of this study was a quasi-experiment with non-randomized pretest-posttest control group design. There were two classes involved, the experiment class used Project Based Learning with STEM approach and control class used Project-Based Learning without STEM approach. A STEM Literacy test instrument was developed to measure students STEM literacy which consists of science literacy, mathematics literacy, and technology-engineering literacy. The analysis showed that there were significant differences on improvement science literacy, mathematics technology-engineering between experiment class and control class with effect size more than 0.8 (large effect). The difference of improvement of STEM literacy between experiment class and control class is caused by the existence of design engineering activity which required students to apply the knowledge from every field of STEM. The challenge that was faced in STEM learning through design engineering activity was how to give the students practice to integrate STEM field in solving the problems. In additional, most of the students gave positive response toward implementation of STEM learning through design boat model project.
Linden, Ariel; Adams, John L; Roberts, Nancy
2006-04-01
Although disease management (DM) has been in existence for over a decade, there is still much uncertainty as to its effectiveness in improving health status and reducing medical cost. The main reason is that most programme evaluations typically follow weak observational study designs that are subject to bias, most notably selection bias and regression to the mean. The regression discontinuity (RD) design may be the best alternative to randomized studies for evaluating DM programme effectiveness. The most crucial element of the RD design is its use of a 'cut-off' score on a pre-test measure to determine assignment to intervention or control. A valuable feature of this technique is that the pre-test measure does not have to be the same as the outcome measure, thus maximizing the programme's ability to use research-based practice guidelines, survey instruments and other tools to identify those individuals in greatest need of the programme intervention. Similarly, the cut-off score can be based on clinical understanding of the disease process, empirically derived, or resource-based. In the RD design, programme effectiveness is determined by a change in the pre-post relationship at the cut-off point. While the RD design is uniquely suitable for DM programme evaluation, its success will depend, in large part, on fundamental changes being made in the way DM programmes identify and assign individuals to the programme intervention.
Testing for carryover effects after cessation of treatments: a design approach.
Sturdevant, S Gwynn; Lumley, Thomas
2016-08-02
Recently, trials addressing noisy measurements with diagnosis occurring by exceeding thresholds (such as diabetes and hypertension) have been published which attempt to measure carryover - the impact that treatment has on an outcome after cessation. The design of these trials has been criticised and simulations have been conducted which suggest that the parallel-designs used are not adequate to test this hypothesis; two solutions are that either a differing parallel-design or a cross-over design could allow for diagnosis of carryover. We undertook a systematic simulation study to determine the ability of a cross-over or a parallel-group trial design to detect carryover effects on incident hypertension in a population with prehypertension. We simulated blood pressure and focused on varying criteria to diagnose systolic hypertension. Using the difference in cumulative incidence hypertension to analyse parallel-group or cross-over trials resulted in none of the designs having acceptable Type I error rate. Under the null hypothesis of no carryover the difference is well above the nominal 5 % error rate. When a treatment is effective during the intervention period, reliable testing for a carryover effect is difficult. Neither parallel-group nor cross-over designs using the difference in cumulative incidence appear to be a feasible approach. Future trials should ensure their design and analysis is validated by simulation.
Dumont, Cyrielle; Lestini, Giulia; Le Nagard, Hervé; Mentré, France; Comets, Emmanuelle; Nguyen, Thu Thuy; Group, For The Pfim
2018-03-01
Nonlinear mixed-effect models (NLMEMs) are increasingly used for the analysis of longitudinal studies during drug development. When designing these studies, the expected Fisher information matrix (FIM) can be used instead of performing time-consuming clinical trial simulations. The function PFIM is the first tool for design evaluation and optimization that has been developed in R. In this article, we present an extended version, PFIM 4.0, which includes several new features. Compared with version 3.0, PFIM 4.0 includes a more complete pharmacokinetic/pharmacodynamic library of models and accommodates models including additional random effects for inter-occasion variability as well as discrete covariates. A new input method has been added to specify user-defined models through an R function. Optimization can be performed assuming some fixed parameters or some fixed sampling times. New outputs have been added regarding the FIM such as eigenvalues, conditional numbers, and the option of saving the matrix obtained after evaluation or optimization. Previously obtained results, which are summarized in a FIM, can be taken into account in evaluation or optimization of one-group protocols. This feature enables the use of PFIM for adaptive designs. The Bayesian individual FIM has been implemented, taking into account a priori distribution of random effects. Designs for maximum a posteriori Bayesian estimation of individual parameters can now be evaluated or optimized and the predicted shrinkage is also reported. It is also possible to visualize the graphs of the model and the sensitivity functions without performing evaluation or optimization. The usefulness of these approaches and the simplicity of use of PFIM 4.0 are illustrated by two examples: (i) an example of designing a population pharmacokinetic study accounting for previous results, which highlights the advantage of adaptive designs; (ii) an example of Bayesian individual design optimization for a pharmacodynamic study, showing that the Bayesian individual FIM can be a useful tool in therapeutic drug monitoring, allowing efficient prediction of estimation precision and shrinkage for individual parameters. PFIM 4.0 is a useful tool for design evaluation and optimization of longitudinal studies in pharmacometrics and is freely available at http://www.pfim.biostat.fr. Copyright © 2018 Elsevier B.V. All rights reserved.
DOT National Transportation Integrated Search
1999-02-01
This report details a project to study the relationship between highway design and human behavior as influenced by roadside environments. The project was developed in two phases. In the visualization phase, computer simulation was used to model an ac...
LifeSat engineering in-house vehicle design
NASA Technical Reports Server (NTRS)
Adkins, A.; Badhwar, G.; Bryant, L.; Caram, J.; Conley, G.; Crull, T.; Cuthbert, P.; Darcy, E.; Delaune, P.; Edeen, M.
1992-01-01
The LifeSat program was initiated to research the effects of microgravity and cosmic radiation on living organisms. The effects of long-term human exposure to free-space radiation fields over a range of gravitational environments has long been recognized as one of the primary design uncertainties for human space exploration. A critical design issue in the radiation biology requirements was the lack of definition of the minimum radiation absorbed dosage required to produce statistically meaningful data. The Phase A study produced a spacecraft conceptual design resembling a Discoverer configuration with a total weight of approximately 2800 pounds that would carry a 525-pound payload module (45 inches in diameter and 36 inches long) and support up to 12 rodents and a general biology module supporting lower life forms for an on-orbit duration of up to 60 days. The phase B conceptual designs focused on gravitational biology requirements and only briefly addressed the design impacts of the shift toward radiobiological science that occurred during the latter half of the Phase B studies.
Study Links Learning Design to Changes in Knowledge, Beliefs, and Behaviors. Lessons from Research
ERIC Educational Resources Information Center
Killion, Joellen
2015-01-01
In this study of 16 teachers in two primary schools in the Netherlands, researchers built on findings from previous studies to demonstrate that a thoughtfully designed professional development program can be "effective and sustainable, if certain conditions are met" (p. 772) in changing teachers' knowledge, beliefs, perceived problems,…
Federal Register 2010, 2011, 2012, 2013, 2014
2010-12-29
... well-implemented experimental or quasi-experimental studies that demonstrate the program has a sizeable... study or well- designed and well-implemented quasi-experimental study that supports the effectiveness of... moderate evidence: (1) At least one well-designed and well-implemented experimental or quasi-experimental...
Design Principles of Worked Examples: A Review of the Empirical Studies
ERIC Educational Resources Information Center
Shen, Chun-Yi; Tsai, Hui-Chun
2009-01-01
Many researchers investigated the efficacy of using worked examples in classroom instruction and provided evidence in the effectiveness of worked example instruction in mathematics, computer programming, physics, and etc. However, there are limited studies in worked example design. The purpose of this study is to generate the instructional design…
Strategically Focused Training in Six Sigma Way: A Case Study
ERIC Educational Resources Information Center
Pandey, Ashish
2007-01-01
Purpose: The purpose of the current study is to examine the utility of Six Sigma interventions as a performance measure and explore its applicability for making the training design and delivery operationally efficient and strategically effective. Design/methodology/approach: This is a single revelatory case study. Data were collected from multiple…
Graziose, Matthew M; Downs, Shauna M; O'Brien, Quentin; Fanzo, Jessica
2018-02-01
To systematically review the design, implementation and effectiveness of mass media and nutrition education interventions for improving infant and young child feeding (IYCF) practices and related psychosocial factors. A search of PubMed, Embase and PsycINFO databases, a Google search, and a consultation with experts in the field of IYCF performed in July 2016. Low- and middle-income countries, as defined by the World Bank Group. Eligible studies: included a mass media component (with or without nutrition education); conducted a pre-post evaluation (with or without a control group); assessed IYCF knowledge, attitudes, beliefs and/or practices; and were published in English between 2000 and present. Eighteen unique studies were identified that examined the effect of mass media (types included: television; print; voice and/or SMS (text) messages; radio; megaphones/loudspeakers; videos; social media; songs/dramas) and nutrition education interventions on IYCF practices within thirteen countries. Of these, fifteen studies reported improvements in breast- and/or complementary feeding practices, using indicators recommended by the WHO, and six studies reported improvements in related psychosocial factors. However, little detail was provided on the use of formative research, a formal behaviour change theory and behaviour change techniques. Few studies reported both dose delivered and participants' exposure to the intervention. Despite evidence of effectiveness, few common elements in the design of interventions were identified. Future research should consistently report these details to open the 'black box' of IYCF interventions, identify effective design components and ensure replicability.
Biel, Rachel; Brame, Cynthia J.
2016-01-01
Online courses are a large and growing part of the undergraduate education landscape, but many biology instructors are skeptical about the effectiveness of online instruction. We reviewed studies comparing the effectiveness of online and face-to-face (F2F) undergraduate biology courses. Five studies compared student performance in multiple course sections at community colleges, while eight were smaller scale and compared student performance in particular biology courses at a variety of types of institutions. Of the larger-scale studies, two found that students in F2F sections outperformed students in online sections, and three found no significant difference; it should be noted, however, that these studies reported little information about course design. Of the eight smaller scale studies, six found no significant difference in student performance between the F2F and online sections, while two found that the online sections outperformed the F2F sections. In alignment with general findings about online teaching and learning, these results suggest that well-designed online biology courses can be effective at promoting student learning. Three recommendations for effective online instruction in biology are given: the inclusion of an online orientation to acclimate students to the online classroom; student-instructor and student-student interactions facilitated through synchronous and asynchronous communication; and elements that prompt student reflection and self-assessment. We conclude that well-designed online biology courses can be as effective as their traditional counterparts, but that more research is needed to elucidate specific course elements and structures that can maximize online students’ learning of key biology skills and concepts. PMID:28101268
Biel, Rachel; Brame, Cynthia J
2016-12-01
Online courses are a large and growing part of the undergraduate education landscape, but many biology instructors are skeptical about the effectiveness of online instruction. We reviewed studies comparing the effectiveness of online and face-to-face (F2F) undergraduate biology courses. Five studies compared student performance in multiple course sections at community colleges, while eight were smaller scale and compared student performance in particular biology courses at a variety of types of institutions. Of the larger-scale studies, two found that students in F2F sections outperformed students in online sections, and three found no significant difference; it should be noted, however, that these studies reported little information about course design. Of the eight smaller scale studies, six found no significant difference in student performance between the F2F and online sections, while two found that the online sections outperformed the F2F sections. In alignment with general findings about online teaching and learning, these results suggest that well-designed online biology courses can be effective at promoting student learning. Three recommendations for effective online instruction in biology are given: the inclusion of an online orientation to acclimate students to the online classroom; student-instructor and student-student interactions facilitated through synchronous and asynchronous communication; and elements that prompt student reflection and self-assessment. We conclude that well-designed online biology courses can be as effective as their traditional counterparts, but that more research is needed to elucidate specific course elements and structures that can maximize online students' learning of key biology skills and concepts.
Shadish, William R; Zelinsky, Nicole A M; Vevea, Jack L; Kratochwill, Thomas R
2016-09-01
The published literature often underrepresents studies that do not find evidence for a treatment effect; this is often called publication bias. Literature reviews that fail to include such studies may overestimate the size of an effect. Only a few studies have examined publication bias in single-case design (SCD) research, but those studies suggest that publication bias may occur. This study surveyed SCD researchers about publication preferences in response to simulated SCD results that show a range of small to large effects. Results suggest that SCD researchers are more likely to submit manuscripts that show large effects for publication and are more likely to recommend acceptance of manuscripts that show large effects when they act as a reviewer. A nontrivial minority of SCD researchers (4% to 15%) would drop 1 or 2 cases from the study if the effect size is small and then submit for publication. This article ends with a discussion of implications for publication practices in SCD research. © 2016 Society for the Experimental Analysis of Behavior.
The Strategic Thinking Skills of Hong Kong School Leaders: Usage and Effectiveness
ERIC Educational Resources Information Center
Pang, Nicholas Sun-Keung; Pisapia, John
2012-01-01
The purpose of this study was to identify strategic thinking skills that distinguish effective school leaders in Hong Kong. Three constructs framed the study: strategic thinking skills, organizational-personal characteristics, and school leader effectiveness. This study used a quantitative non-experimental design, and univariate and correlation…
Mysid (Mysidopsis bahia) life-cycle test: Design comparisons and assessment
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lussier, S.M.; Champlin, D.; Kuhn, A.
1996-12-31
This study examines ASTM Standard E1191-90, ``Standard Guide for Conducting Life-cycle Toxicity Tests with Saltwater Mysids,`` 1990, using Mysidopsis bahia, by comparing several test designs to assess growth, reproduction, and survival. The primary objective was to determine the most labor efficient and statistically powerful test design for the measurement of statistically detectable effects on biologically sensitive endpoints. Five different test designs were evaluated varying compartment size, number of organisms per compartment and sex ratio. Results showed that while paired organisms in the ASTM design had the highest rate of reproduction among designs tested, no individual design had greater statistical powermore » to detect differences in reproductive effects. Reproduction was not statistically different between organisms paired in the ASTM design and those with randomized sex ratios using larger test compartments. These treatments had numerically higher reproductive success and lower within tank replicate variance than treatments using smaller compartments where organisms were randomized, or had a specific sex ratio. In this study, survival and growth were not statistically different among designs tested. Within tank replicate variability can be reduced by using many exposure compartments with pairs, or few compartments with many organisms in each. While this improves variance within replicate chambers, it does not strengthen the power of detection among treatments in the test. An increase in the number of true replicates (exposure chambers) to eight will have the effect of reducing the percent detectable difference by a factor of two.« less
Quantifying fish habitat associated with stream simulation design culverts in northern Wisconsin
A. Timm; D. Higgins; J. Stanovick; R. Kolka; S. Eggert
2017-01-01
This study investigated the effects of culvert replacement design on fish habitat and fish weight by comparing substrate diversity and weight at three stream simulation (SS)-design and three bankfull and backwater (BB)-design sites on the Chequamegon-Nicolet National Forest, Wisconsin. Stream channel cross-sections, Wolman substrate particle counts, and single-pass...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-02-17
... adaptation of an interrupted time series design that relies on the comparison of treatment effects on a... group designs (as defined in this notice), interrupted time series designs (as defined in this notice... series design means a type of quasi-experimental study (as defined in this notice) in which the outcome...