Clinical leadership: using observations of care to focus risk management and quality improvement activities in the clinical setting.

PubMed

Ferguson, Lorraine; Calvert, Judy; Davie, Marilyn; Fallon, Mark; Fred, Nada; Gersbach, Vicki; Sinclair, Lynn

2007-04-01

In an era when patient safety and quality of care are a daily concern for health care professionals, it is important for nurse managers and other clinical leaders to have a repertoire of skills and interventions that can be used to motivate and engage clinical teams in risk assessment and continuous quality improvement at the level of patient care delivery. This paper describes how a cohort of clinical leaders who were undertaking a leadership development program used a relatively simple, patient-focused intervention called the 'observation of care' to help focus the clinical team's attention on areas for improvement within the clinical setting. The main quality and safety themes arising out of the observations that were undertaken by the Clinical Leaders (CLs) were related to the environment, occupational health and safety, communication and team function, clinical practice and patient care. The observations of care also provided the CLs with many opportunities to acknowledge and celebrate exemplary practice as it was observed as a means of enhancing the development of a quality and safety culture within the clinical setting. The 'observation of care' intervention can be used by Clinical Leader's to engage and motivate clinical teams to focus on continuously improving the safety and quality of their own work environment and the care delivered to patients within that environment.

Figure of merit and different combinations of observational data sets

NASA Astrophysics Data System (ADS)

Su, Qiping; Tuo, Zhong-Liang; Cai, Rong-Gen

2011-11-01

To constrain cosmological parameters, one often makes a joint analysis with different combinations of observational data sets. In this paper we take the figure of merit (FoM) for Dark Energy Task Force fiducial model (Chevallier-Polarski-Linder model) to estimate goodness of different combinations of data sets, which include 11 widely used observational data sets (type Ia supernovae, observational hubble parameter, baryon acoustic oscillation, cosmic microwave background, x-ray cluster baryon mass fraction, and gamma-ray bursts). We analyze different combinations and make a comparison for two types of combinations based on two types of basic combinations, which are often adopted in the literature. We find two sets of combinations, which have a strong ability to constrain the dark energy parameters: one has the largest FoM, and the other contains less observational data with a relatively large FoM and a simple fitting procedure.

The Significance of HIV ‘Blips’ in Resource-Limited Settings: Is It the Same? Analysis of the Treat Asia HIV Observational Database (TAHOD) and the Australian HIV Observational Database (AHOD)

PubMed Central

Kanapathipillai, Rupa; McManus, Hamish; Kamarulzaman, Adeeba; Lim, Poh Lian; Templeton, David J.; Law, Matthew; Woolley, Ian

2014-01-01

Introduction Magnitude and frequency of HIV viral load blips in resource-limited settings, has not previously been assessed. This study was undertaken in a cohort from a high income country (Australia) known as AHOD (Australian HIV Observational Database) and another cohort from a mixture of Asian countries of varying national income per capita, TAHOD (TREAT Asia HIV Observational Database). Methods Blips were defined as detectable VL (≥ 50 copies/mL) preceded and followed by undetectable VL (<50 copies/mL). Virological failure (VF) was defined as two consecutive VL ≥50 copies/ml. Cox proportional hazard models of time to first VF after entry, were developed. Results 5040 patients (AHOD n = 2597 and TAHOD n = 2521) were included; 910 (18%) of patients experienced blips. 744 (21%) and 166 (11%) of high- and middle/low-income participants, respectively, experienced blips ever. 711 (14%) experienced blips prior to virological failure. 559 (16%) and 152 (10%) of high- and middle/low-income participants, respectively, experienced blips prior to virological failure. VL testing occurred at a median frequency of 175 and 91 days in middle/low- and high-income sites, respectively. Longer time to VF occurred in middle/low income sites, compared with high-income sites (adjusted hazards ratio (AHR) 0.41; p<0.001), adjusted for year of first cART, Hepatitis C co-infection, cART regimen, and prior blips. Prior blips were not a significant predictor of VF in univariate analysis (AHR 0.97, p = 0.82). Differing magnitudes of blips were not significant in univariate analyses as predictors of virological failure (p = 0.360 for blip 50–≤1000, p = 0.309 for blip 50–≤400 and p = 0.300 for blip 50–≤200). 209 of 866 (24%) patients were switched to an alternate regimen in the setting of a blip. Conclusion Despite a lower proportion of blips occurring in low/middle-income settings, no significant difference was found between settings. Nonetheless, a

Workload and management of childhood fever at general practice out-of-hours care: an observational cohort study

PubMed Central

de Bont, Eefje G P M; Lepot, Julie M M; Hendrix, Dagmar A S; Loonen, Nicole; Guldemond-Hecker, Yvonne; Dinant, Geert-Jan; Cals, Jochen W L

2015-01-01

Objective Even though childhood fever is mostly self-limiting, children with fever constitute a considerable workload in primary care. Little is known about the number of contacts and management during general practitioners’ (GPs) out-of-hours care. We investigated all fever related telephone contacts, consultations, antibiotic prescriptions and paediatric referrals of children during GP out-of-hours care within 1 year. Design Observational cohort study. Setting and patients We performed an observational cohort study at a large Dutch GP out-of-hours service. Children (<12 years) whose parents contacted the GP out-of-hours service for a fever related illness in 2012 were included. Main outcome measures Number of contacts and consultations, antibiotic prescription rates and paediatric referral rates. Results We observed an average of 14.6 fever related contacts for children per day at GP out-of-hours services, with peaks during winter months. Of 17 170 contacts in 2012, 5343 (31.1%) were fever related and 70.0% resulted in a GP consultation. One in four consultations resulted in an antibiotic prescription. Prescriptions increased by age and referrals to secondary care decreased by age (p<0.001). The majority of parents (89.5%) contacted the out-of-hours service only once during a fever episode (89.5%) and 7.6% of children were referred to secondary care. Conclusions This study shows that childhood fever does account for a large workload at GP out-of-hours services. One in three contacts is fever related and 70% of those febrile children are called in to be assessed by a GP. One in four consultations for childhood fever results in antibiotic prescribing and most consultations are managed in primary care without referral. PMID:25991452

Preschool Children's Interest in Babies: Observations in Naturally-Occurring Settings.

ERIC Educational Resources Information Center

Blakemore, Judith E. Owen

Previous research in laboratory settings has found that preschool girls show more interest in babies than do preschool boys. To validate these findings in natural settings, 71 children at 3 and 5 years of age were observed by their parents as the children interacted with babies in their daily lives. Each child was observed with three different…

Addition of sulphonylurea to metformin does not relevantly change body weight: a prospective observational cohort study (ZODIAC-39).

PubMed

Schrijnders, Dennis; Wever, Raiza; Kleefstra, Nanne; Houweling, Sebastiaan T; van Hateren, Kornelis J J; de Bock, Geertruida H; Bilo, Henk J G; Groenier, Klaas H; Landman, Gijs W D

2016-10-01

To investigate changes in body weight trajectories after the addition of individual sulphonylureas (SUs) to metformin in patients with type 2 diabetes. We conducted a retrospective observational cohort study, in a primary care setting in the Netherlands. Patients aged ≥18 years with type 2 diabetes who were included in the ZODIAC cohort between 1998 and 2012 and who received metformin monotherapy at inclusion (n = 29 195), and had used metformin as monotherapy for at least 1 year before receiving dual therapy through the addition of an SU for at least 1 year were eligible for inclusion. The primary outcome was within-drug yearly change in body weight after receiving add-on therapy with individual SUs during 5 years of follow-up. The secondary outcome was within-drug yearly change in glycated haemoglobin (HbA1c). Annual changes in weight and HbA1c were estimated with linear mixed models, adjusted for age, gender and diabetes duration. A total of 2958 patients were included. No significant weight changes were observed within and between any of the individual SUs after treatment intensification (p = 0.24). In addition, no significant difference in weight between the add-on therapy combinations was observed (p = 0.26). The average HbA1c the year before intensification was 7.2% (55 mmol/mol) and dropped below 7.0% (53 mmol/mol) the year after. In patients with type 2 diabetes treated in primary care, strict glycaemic control can be maintained with SUs used as add-on therapy to metformin, without the offset of relevant weight changes. © 2016 The Authors. Diabetes, Obesity and Metabolism published by John Wiley & Sons Ltd.

Risk factors for acute exacerbations of COPD in a primary care population: a retrospective observational cohort study

PubMed Central

Müllerová, Hana; Shukla, Amit; Hawkins, Adam; Quint, Jennifer

2014-01-01

Objectives To evaluate risk factors associated with exacerbation frequency in primary care. Information on exacerbations of chronic obstructive pulmonary disease (COPD) has mainly been generated by secondary care-based clinical cohorts. Design Retrospective observational cohort study. Setting Electronic medical records database (England and Wales). Participants 58 589 patients with COPD aged ≥40 years with COPD diagnosis recorded between 1 April 2009 and 30 September 2012, and with at least 365 days of follow-up before and after the COPD diagnosis, were identified in the Clinical Practice Research Datalink. Mean age: 69 years; 47% female; mean forced expiratory volume in 1s 60% predicted. Outcome measures Data on moderate or severe exacerbation episodes defined by diagnosis and/or medication codes 12 months following cohort entry were retrieved, together with demographic and clinical characteristics. Associations between patient characteristics and odds of having none versus one, none versus frequent (≥2) and one versus frequent exacerbations over 12 months follow-up were evaluated using multivariate logistic regression models. Results During follow-up, 23% of patients had evidence of frequent moderate-to-severe COPD exacerbations (24% one; 53% none). Independent predictors of increased odds of having exacerbations during the follow-up, either frequent episodes or one episode, included prior exacerbations, increasing dyspnoea score, increasing grade of airflow limitation, females and prior or current history of several comorbidities (eg, asthma, depression, anxiety, heart failure and cancer). Conclusions Primary care-managed patients with COPD at the highest risk of exacerbations can be identified by exploring medical history for the presence of prior exacerbations, greater COPD disease severity and co-occurrence of other medical conditions. PMID:25524545

Observations of a large Dent disease cohort.

PubMed

Blanchard, Anne; Curis, Emmanuel; Guyon-Roger, Tiphaine; Kahila, Diana; Treard, Cyrielle; Baudouin, Véronique; Bérard, Etienne; Champion, Gérard; Cochat, Pierre; Dubourg, Julie; de la Faille, Renaud; Devuyst, Olivier; Deschenes, Georges; Fischbach, Michel; Harambat, Jérôme; Houillier, Pascal; Karras, Alexandre; Knebelmann, Bertrand; Lavocat, Marie-Pierre; Loirat, Chantal; Merieau, Elodie; Niaudet, Patrick; Nobili, François; Novo, Robert; Salomon, Rémi; Ulinski, Tim; Jeunemaître, Xavier; Vargas-Poussou, Rosa

2016-08-01

Dent disease classically combines low-molecular-weight proteinuria, hypercalciuria with nephrocalcinosis, and renal failure. Nephrotic range proteinuria, normal calciuria, and hypokalemia have been rarely reported. It is unknown whether the changes in phenotype observed over time are explained by a decrease in glomerular filtration rate (GFR) or whether there is any phenotype-genotype relationship. To answer this we retrospectively analyzed data from 109 male patients with CLCN5 mutations (Dent-1) and 9 patients with mutation of the OCRL gene (Dent-2). In Dent-1 disease, the estimated GFR decreased with age, by 1.0 to 1.6 ml/min per 1.73 m(2)/yr in the absence and presence of nephrocalcinosis, respectively, with no significant difference. Median values of low-molecular-weight proteinuria were in the nephrotic range and remained at the same level even in late renal disease. End-stage renal disease occurred in 12 patients, at a median age of 40 years. Hypercalciuria decreased with glomerular filtration and was absent in 40% of the patients under 30 and 85% of those over the age of 30. Hypophosphatemia did not resolve with age and calcitriol concentrations were in the upper normal range. Kalemia decreased with age, with half of the patients over the age of 18 presenting with hypokalemia. Thus, no phenotype/genotype correlation was observed in this cohort of patients with Dent disease. Copyright © 2016 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

The influence of comorbidities on mortality in sarcoidosis: a observational prospective cohort study.

PubMed

Nowiński, Adam; Puścińska, Elzbieta; Goljan, Anna; Peradzynska, Joanna; Bednarek, Michal; Korzybski, Damian; Kamiński, Dariusz; Stokłosa, Anna; Czystowska, Monika; Śliwiński, Pawel; Górecka, Dorota

2017-09-01

The aim of this study was to identify the frequency and prevalence of comorbidities in sarcoid patients and to assess their influence on overall mortality in the cohort of patients with sarcoidosis. A cohort of 557 patients with histologically confirmed sarcoidosis diagnosed between 2007 and 2011 and a group of non-sarcoid controls were observed. All patients were carefully observed for comorbidities and mortality. 291 males (52.2%) and 266 females (47.8%) with mean age 48.4 ± 12.0 years in sarcoidosis group and a group of 100 controls with mean age (49.25 ± 10.3) were observed. The mean number of comorbidities in both groups was similar (0.9 ± 0.99 vs 0.81 ± 0.84 NS). The frequency of thyroid disease was significantly higher in sarcoidosis group comparing to controls at the time of diagnosis (OR = 3.62 P = 0.0144). During the observation period (median 58.0 months), 16 patients died (2.9%). The mean number of comorbidities was significantly higher in the groups of non-survivors as compared to survivors (2.8 ± 1.0, vs 0.8 ± 0.9), P < 0.0001. The comorbidity burden has strong impact on mortality in sarcoidosis. Thyroid diseases are more frequent in sarcoidosis than in non-sarcoid controls. © 2015 John Wiley & Sons Ltd.

Energy Setting and Visual Outcomes in SMILE: A Retrospective Cohort Study.

PubMed

Li, Liuyang; Schallhorn, Julie M; Ma, Jiaonan; Cui, Tong; Wang, Yan

2018-01-01

To assess the independent effect of energy setting on postoperative uncorrected distance visual acuity (UDVA) in small incision lenticule extraction (SMILE) and further investigate an optimal energy setting for the 4.5-μm spot-track-distance, which is in wide clinical use. A total of 1,130 eyes were included in a retrospective cohort study from Tianjin Eye Hospital, Tianjin Medical University from April 2015 to July 2016. Energy settings and baseline characteristics were recorded and 3-month UDVA was tested by a nurse blinded to the energy settings used. Multiple regression analysis and generalized estimating equations were used to take into account the correlation between the measurements from two eyes. The 3-month UDVA (mean ± standard deviation) of 125 to 160 nJ (by 5-nJ increments) was 1.39 ± 0.19, 1.40 ± 0.32, 1.33 ± 0.27, 1.36 ± 0.27, 1.34 ± 0.25, 1.29 ± 0.19, 1.36 ± 0.27, and 1.19 ± 0.22, respectively. Energy was significantly associated with postoperative logMAR UDVA in different models and the regression coefficient (β) was robust (β = 0.01, 95% confidence interval = 0.00 to 0.01). The regression coefficient β (0.01, 95% confidence interval = 0.00 to 0.02, P = .0029) of energy (125 to 150 nJ, by 5-nJ increments) on 4.5-μm spot-track-distance was still associated with the logMAR UDVA when adjusted for sex, age, myopia, astigmatism, mean keratometry, central corneal thickness, preoperative logMAR CDVA, and side spot-track-distance. The lower end of the energy studied was associated with a better postoperative UDVA in this population. The spot-track-distance of 4.5 μm with 125 nJ energy was the optimal combination within this range. [J Refract Surg. 2018;34(1):11-16.]. Copyright 2018, SLACK Incorporated.

A comparison of Cox and logistic regression for use in genome-wide association studies of cohort and case-cohort design.

PubMed

Staley, James R; Jones, Edmund; Kaptoge, Stephen; Butterworth, Adam S; Sweeting, Michael J; Wood, Angela M; Howson, Joanna M M

2017-06-01

Logistic regression is often used instead of Cox regression to analyse genome-wide association studies (GWAS) of single-nucleotide polymorphisms (SNPs) and disease outcomes with cohort and case-cohort designs, as it is less computationally expensive. Although Cox and logistic regression models have been compared previously in cohort studies, this work does not completely cover the GWAS setting nor extend to the case-cohort study design. Here, we evaluated Cox and logistic regression applied to cohort and case-cohort genetic association studies using simulated data and genetic data from the EPIC-CVD study. In the cohort setting, there was a modest improvement in power to detect SNP-disease associations using Cox regression compared with logistic regression, which increased as the disease incidence increased. In contrast, logistic regression had more power than (Prentice weighted) Cox regression in the case-cohort setting. Logistic regression yielded inflated effect estimates (assuming the hazard ratio is the underlying measure of association) for both study designs, especially for SNPs with greater effect on disease. Given logistic regression is substantially more computationally efficient than Cox regression in both settings, we propose a two-step approach to GWAS in cohort and case-cohort studies. First to analyse all SNPs with logistic regression to identify associated variants below a pre-defined P-value threshold, and second to fit Cox regression (appropriately weighted in case-cohort studies) to those identified SNPs to ensure accurate estimation of association with disease.

Latent Variable Regression 4-Level Hierarchical Model Using Multisite Multiple-Cohorts Longitudinal Data. CRESST Report 801

ERIC Educational Resources Information Center

Choi, Kilchan

2011-01-01

This report explores a new latent variable regression 4-level hierarchical model for monitoring school performance over time using multisite multiple-cohorts longitudinal data. This kind of data set has a 4-level hierarchical structure: time-series observation nested within students who are nested within different cohorts of students. These…

Recurrence of tuberculosis in a low-incidence setting without directly observed treatment: Victoria, Australia, 2002-2014.

PubMed

Dale, K D; Globan, M; Tay, E L; Trauer, J M; Trevan, P G; Denholm, J T

2017-05-01

Victoria, Australia, is an industrialised setting with low tuberculosis (TB) incidence and universal health care. Individually tailored adherence support for self-administered daily anti-tuberculosis treatment is provided. Directly observed treatment (DOT) is very rarely used. To review the rate of recurrent TB in Victoria between 2002 and 2014. This was a retrospective cohort study. All recurrent episodes of TB were reviewed and 24-locus MIRU-VNTR (mycobacterial interspersed repetitive units-variable number of tandem repeats) molecular typing was used where possible to determine the likelihood of relapse or reinfection. Of 4766 notifications, 32 (0.7%) were recurrent episodes. Of 20 episodes that occurred in patients who had previously completed treatment, 11 were culture-positive (0.4% of 3012 culture-positive episodes): 9 were likely relapses (distinguishable at no more than one of 24 loci) and two were likely reinfections, giving a TB relapse rate among culture-positive episodes of 52.5/100 000 person-years (mean time to study end per patient of 5.7 years). The median time until relapse was 18 months (interquartile range 12-30). The low rate of relapse in our setting demonstrates that individually tailored adherence support for self-administered anti-tuberculosis treatment can achieve excellent treatment outcomes.

Plasma proteome analysis in patients with pulmonary arterial hypertension: an observational cohort study.

PubMed

Rhodes, Christopher J; Wharton, John; Ghataorhe, Pavandeep; Watson, Geoffrey; Girerd, Barbara; Howard, Luke S; Gibbs, J Simon R; Condliffe, Robin; Elliot, Charles A; Kiely, David G; Simonneau, Gerald; Montani, David; Sitbon, Olivier; Gall, Henning; Schermuly, Ralph T; Ghofrani, H Ardeschir; Lawrie, Allan; Humbert, Marc; Wilkins, Martin R

2017-09-01

Idiopathic and heritable pulmonary arterial hypertension form a rare but molecularly heterogeneous disease group. We aimed to measure and validate differences in plasma concentrations of proteins that are associated with survival in patients with idiopathic or heritable pulmonary arterial hypertension to improve risk stratification. In this observational cohort study, we enrolled patients with idiopathic or heritable pulmonary arterial hypertension from London (UK; cohorts 1 and 2), Giessen (Germany; cohort 3), and Paris (France; cohort 4). Blood samples were collected at routine clinical appointment visits, clinical data were collected within 30 days of blood sampling, and biochemical data were collected within 7 days of blood sampling. We used an aptamer-based assay of 1129 plasma proteins, and patient clinical details were concealed to the technicians. We identified a panel of prognostic proteins, confirmed with alternative targeted assays, which we evaluated against the established prognostic risk equation for pulmonary arterial hypertension derived from the REVEAL registry. All-cause mortality was the primary endpoint. 20 proteins differentiated survivors and non-survivors in 143 consecutive patients with idiopathic or heritable pulmonary arterial hypertension with 2 years' follow-up (cohort 1) and in a further 75 patients with 2·5 years' follow-up (cohort 2). Nine proteins were both prognostic independent of plasma NT-proBNP concentrations and confirmed by targeted assays. The functions of these proteins relate to myocardial stress, inflammation, pulmonary vascular cellular dysfunction and structural dysregulation, iron status, and coagulation. A cutoff-based score using the panel of nine proteins provided prognostic information independent of the REVEAL equation, improving the C statistic from area under the curve 0·83 (for REVEAL risk score, 95% CI 0·77-0·89; p<0·0001) to 0·91 (for panel and REVEAL 0·87-0·96; p<0·0001) and improving

Prospective cohort study of a new vacuum delivery device to assist with complicated labour in low-resource settings.

PubMed

Khan, Mishal; Hashmani, Farah Naz; Ahmed, Sajjad; Ahmed, Owais; Asim, Shabnam S; Wajahat, Yasmin; Sobani, Shoaib; Syed, Shershah; Qazi, Fahad

2015-02-01

Currently available vacuum devices used to assist women undergoing complicated labour are unsuitable for use in low-resource settings. The objective of this study was to evaluate the safety and feasibility of a new low-cost vacuum device, named Koohi Goth Vacuum Delivery System (KGVDS), designed for use in low-resource settings. A hospital-based, multicentre, prospective cohort study with no control group was conducted in Karachi, Pakistan. After training, KGVDS devices were made available for use by labour room staff at their discretion when instrumental delivery was indicated. Women to whom KGVDS was applied were followed from the start of labour until discharge. Feasibility was assessed in terms of successful expulsion of the foetal head following application of KGVDS and ease of use ratings. Safety was assessed by observing maternal and newborn post-delivery outcomes prior to discharge. Koohi Goth Vacuum Delivery System was applied to 137 women requiring instrumental delivery, of whom 111 (81%; 95% CI = 74-88%) successfully expelled the foetal head assisted by KGVDS and 103 (75%) stated that they would agree to use KGVDS again. There were no serious maternal or neonatal injuries or infections related to KGVDS use. The mean score for 'ease of use' given by doctors and midwives using the device was 8 of 10. Koohi Goth Vacuum Delivery System was feasible and safe to use for assisting complicated deliveries in low-resource hospitals in this initial evaluation. Our results indicate that this new device may have the potential to improve birth outcomes in settings where most mortality occurs and that further evaluations should be conducted. © 2014 John Wiley & Sons Ltd.

A Photometric Observing Program at the VATT: Setting Up a Calibration Field

NASA Astrophysics Data System (ADS)

Davis Philip, A. G.; Boyle, R. P.; Janusz, R.

2009-05-01

Philip and Boyle have been making Strömgren and then Strömvil photometric observations of open and globular clusters at the Vatican Advanced Technology Telescope located on Mt. Graham in Arizona. Our aim is to obtain CCD photometric indices good to 0.01 magnitude. Indices of this quality can later be analyzed to yield estimates of temperature, luminosity and metallicity. But we have found that the CCD chip does not yield photometry of this quality without further corrections. Our most observed cluster is the open cluster, M 67. This cluster is also very well observed in the literature. We took the best published values and created a set of "standard" stars for our field. Taking our CCD results we could calculate deltas, as a function of position on the chip, which we then applied to all the CCD frames that we obtained. With this procedure we were able to obtain the precision of 0.01 magnitudes in all the fields that we observed. When we started we were able to use the "A" two-inch square Strömgren four-color set from KPNO. Later the Vatican Observatory bought a set of 3.48 inch square Strömgren filters, The Vatican Observatory had a set of circular Vilnius filters There was also an X filter. These eight filters made our Strömvil set.

Cohort profile: The lidA Cohort Study—a German Cohort Study on Work, Age, Health and Work Participation

PubMed Central

Hasselhorn, Hans Martin; Peter, Richard; Rauch, Angela; Schröder, Helmut; Swart, Enno; Bender, Stefan; du Prel, Jean-Baptist; Ebener, Melanie; March, Stefanie; Trappmann, Mark; Steinwede, Jacob; Müller, Bernd Hans

2014-01-01

The lidA Cohort Study (German Cohort Study on Work, Age, Health and Work Participation) was set up to investigate and follow the effects of work and work context on the physical and psychological health of the ageing workforce in Germany and subsequently on work participation. Cohort participants are initially employed people subject to social security contributions and born in either 1959 (n = 2909) or 1965 (n = 3676). They were personally interviewed in their homes in 2011 and will be visited every 3 years. Data collection comprises socio-demographic data, work and private exposures, work ability, work and work participation attitudes, health, health-related behaviour, personality and attitudinal indicators. Employment biographies are assessed using register data. Subjective health reports and physical strength measures are complemented by health insurance claims data, where permission was given. A conceptual framework has been developed for the lidA Cohort Study within which three confirmatory sub-models assess the interdependencies of work and health considering age, gender and socioeconomic status. The first set of the data will be available to the scientific community by 2015. Access will be given by the Research Data Centre of the German Federal Employment Agency at the Institute for Employment Research (http://fdz.iab.de/en.aspx). PMID:24618186

Utilisation of extended release quetiapine (Seroquel XL™): Results from an observational cohort study in England.

PubMed

Osborne, V; Davies, M; Layton, D; Shakir, S A W

2016-03-01

A post-authorisation safety study was carried out as part of the EU Risk Management Plan to examine the long-term (up to 12 months) use of quetiapine XL as prescribed in general practice in England. To present a description of the drug utilisation characteristics of quetiapine XL. An observational, population-based cohort design using the technique of Modified Prescription-Event Monitoring (M-PEM). Patients were identified from dispensed prescriptions issued by general practitioners (GPs) for quetiapine XL between September 2008 and February 2013. Questionnaires were sent to GPs 12 months following the 1st prescription for each individual patient, requesting drug utilisation information. Cohort accrual was extended to recruit additional elderly patients (special population of interest). Summary descriptive statistics were calculated. The final M-PEM cohort consisted of 13,276 patients; median age 43 years (IQR: 33, 55) and 59.0% females. Indications for prescribing included bipolar disorder (n=3820), MDD (n=2844), schizophrenia (n=2373) and other (non-licensed) indications (n=3750). Where specified, 59.3% (7869/13,276) were reported to have used quetiapine IR (immediate release formulation) previously at any time. The median start dose was highest for patients with schizophrenia (300 mg/day [IQR 150, 450]). The final elderly cohort consisted of 3127 patients and 28.5% had indications associated with dementia. The median start dose for elderly patients was highest for patients with schizophrenia or BD (both 100mg/day [IQR 50, 300]). The prevalence of off-label prescribing in terms of indication and high doses was common, as was use in special populations such as the very elderly. Whilst off-label use may be unavoidable in certain situations, GPs may need to re-evaluate prescribing in circumstances where there may be safety concerns. This study demonstrates the ongoing importance of observational studies such as M-PEM to gather real-world clinical data to support the

Measuring Afterschool Program Quality Using Setting-Level Observational Approaches

ERIC Educational Resources Information Center

Oh, Yoonkyung; Osgood, D. Wayne; Smith, Emilie P.

2015-01-01

The importance of afterschool hours for youth development is widely acknowledged, and afterschool settings have recently received increasing attention as an important venue for youth interventions, bringing a growing need for reliable and valid measures of afterschool quality. This study examined the extent to which the two observational tools,…

The MANGUA Project: A Population-Based HIV Cohort in Guatemala

PubMed Central

García, Juan Ignacio; Samayoa, Blanca; Sabidó, Meritxell; Prieto, Luis Alberto; Nikiforov, Mikhail; Pinzón, Rodolfo; Santa Marina de León, Luis Roberto; Ortiz, José Fernando; Ponce, Ernesto; Mejía, Carlos Rodolfo; Arathoon, Eduardo; Casabona, Jordi; Study Group, The Mangua Cohort

2015-01-01

Introduction. The MANGUA cohort is an ongoing multicenter, observational study of people living with HIV/AIDS in Guatemala. The cohort is based on the MANGUA application which is an electronic database to capture essential data from the medical records of HIV patients in care. Methods. The cohort enrolls HIV-positive adults ≥16 years of age. A predefined set of sociodemographic, behavioral, clinical, and laboratory data are registered at entry to the cohort study. Results. As of October 1st, 2012, 21 697 patients had been included in the MANGUA cohort (median age: 33 years, 40.3% female). At enrollment 74.1% had signs of advanced HIV infection and only 56.3% had baseline CD4 cell counts. In the first 12 months after starting antiretroviral treatment 26.9% (n = 3938) of the patients were lost to the program. Conclusions. The implementation of a cohort of HIV-positive patients in care in Guatemala is feasible and has provided national HIV indicators to monitor and evaluate the HIV epidemic. The identified percentages of late presenters and high rates of LTFU will help the Ministry to target their current efforts in improving access to diagnosis and care. PMID:26425365

The MANGUA Project: A Population-Based HIV Cohort in Guatemala.

PubMed

García, Juan Ignacio; Samayoa, Blanca; Sabidó, Meritxell; Prieto, Luis Alberto; Nikiforov, Mikhail; Pinzón, Rodolfo; Santa Marina de León, Luis Roberto; Ortiz, José Fernando; Ponce, Ernesto; Mejía, Carlos Rodolfo; Arathoon, Eduardo; Casabona, Jordi; Study Group, The Mangua Cohort

2015-01-01

Introduction. The MANGUA cohort is an ongoing multicenter, observational study of people living with HIV/AIDS in Guatemala. The cohort is based on the MANGUA application which is an electronic database to capture essential data from the medical records of HIV patients in care. Methods. The cohort enrolls HIV-positive adults ≥16 years of age. A predefined set of sociodemographic, behavioral, clinical, and laboratory data are registered at entry to the cohort study. Results. As of October 1st, 2012, 21 697 patients had been included in the MANGUA cohort (median age: 33 years, 40.3% female). At enrollment 74.1% had signs of advanced HIV infection and only 56.3% had baseline CD4 cell counts. In the first 12 months after starting antiretroviral treatment 26.9% (n = 3938) of the patients were lost to the program. Conclusions. The implementation of a cohort of HIV-positive patients in care in Guatemala is feasible and has provided national HIV indicators to monitor and evaluate the HIV epidemic. The identified percentages of late presenters and high rates of LTFU will help the Ministry to target their current efforts in improving access to diagnosis and care.

Safety and efficacy of hysteroscopic sterilization compared with laparoscopic sterilization: an observational cohort study

PubMed Central

Mao, Jialin; Pfeifer, Samantha; Schlegel, Peter

2015-01-01

Objective To compare the safety and efficacy of hysteroscopic sterilization with the “Essure” device with laparoscopic sterilization in a large, all-inclusive, state cohort. Design Population based cohort study. Settings Outpatient interventional setting in New York State. Participants Women undergoing interval sterilization procedure, including hysteroscopic sterilization with Essure device and laparoscopic surgery, between 2005 and 2013. Main outcomes measures Safety events within 30 days of procedures; unintended pregnancies and reoperations within one year of procedures. Mixed model accounting for hospital clustering was used to compare 30 day and 1 year outcomes, adjusting for patient characteristics and other confounders. Time to reoperation was evaluated using frailty model for time to event analysis. Results We identified 8048 patients undergoing hysteroscopic sterilization and 44 278 undergoing laparoscopic sterilization between 2005 and 2013 in New York State. There was a significant increase in the use of hysteroscopic procedures during this period, while use of laparoscopic sterilization decreased. Patients undergoing hysteroscopic sterilization were older than those undergoing laparoscopic sterilization and were more likely to have a history of pelvic inflammatory disease (10.3% v 7.2%, P<0.01), major abdominal surgery (9.4% v 7.9%, P<0.01), and cesarean section (23.2% v 15.4%, P<0.01). At one year after surgery, hysteroscopic sterilization was not associated with a higher risk of unintended pregnancy (odds ratio 0.84 (95% CI 0.63 to 1.12)) but was associated with a substantially increased risk of reoperation (odds ratio 10.16 (7.47 to 13.81)) compared with laparoscopic sterilization. Conclusions Patients undergoing hysteroscopic sterilization have a similar risk of unintended pregnancy but a more than 10-fold higher risk of undergoing reoperation compared with patients undergoing laparoscopic sterilization. Benefits and risks of both procedures

The complete set of Cassini's UVIS occultation observations of Enceladus plume: model fits

NASA Astrophysics Data System (ADS)

Portyankina, G.; Esposito, L. W.; Hansen, C. J.

2017-12-01

Since the discovery in 2005, plume of Enceladus was observed by most of the instruments onboard Cassini spacecraft. Ultraviolet Imaging Spectrograph (UVIS) have observed Enceladus plume and collimated jets embedded in it in occultational geometry on 6 different occasions. We have constructed a 3D direct simulation Monte Carlo (DSMC) model for Enceladus jets and apply it to the analysis of the full set of UVIS occultation observations conducted during Cassini's mission from 2005 to 2017. The Monte Carlo model tracks test particles from their source at the surface into space. The initial positions of all test particles for a single jet are fixed to one of 100 jets sources identified by Porco et al. (2014). The initial three-dimensional velocity of each particle contains two components: a velocity Vz which is perpendicular to the surface, and a thermal velocity which is isotropic in the upward hemisphere. The direction and speed of the thermal velocity of each particle is chosen randomly but the ensemble moves isotropically at a speed which satisfies a Boltzmann distribution for a given temperature Tth. A range for reasonable Vz is then determined by requiring that modeled jet widths match the observed ones. Each model run results in a set of coordinates and velocities of a given set of test particles. These are converted to the test particle number densities and then integrated along LoS for each time step of the occultation observation. The geometry of the observation is calculated using SPICE. The overarching result of the simulation run is a test particle number density along LoS for each time point during the occultation observation for each of the jets separately. To fit the model to the data, we integrate all jets that are crossed by the LoS at each point during an observation. The relative strength of the jets must be determined to fit the observed UVIS curves. The results of the fits are sets of active jets for each occultation. Each UVIS occultation

Empirical performance of the calibrated self-controlled cohort analysis within temporal pattern discovery: lessons for developing a risk identification and analysis system.

PubMed

Norén, G Niklas; Bergvall, Tomas; Ryan, Patrick B; Juhlin, Kristina; Schuemie, Martijn J; Madigan, David

2013-10-01

Observational healthcare data offer the potential to identify adverse drug reactions that may be missed by spontaneous reporting. The self-controlled cohort analysis within the Temporal Pattern Discovery framework compares the observed-to-expected ratio of medical outcomes during post-exposure surveillance periods with those during a set of distinct pre-exposure control periods in the same patients. It utilizes an external control group to account for systematic differences between the different time periods, thus combining within- and between-patient confounder adjustment in a single measure. To evaluate the performance of the calibrated self-controlled cohort analysis within Temporal Pattern Discovery as a tool for risk identification in observational healthcare data. Different implementations of the calibrated self-controlled cohort analysis were applied to 399 drug-outcome pairs (165 positive and 234 negative test cases across 4 health outcomes of interest) in 5 real observational databases (four with administrative claims and one with electronic health records). Performance was evaluated on real data through sensitivity/specificity, the area under receiver operator characteristics curve (AUC), and bias. The calibrated self-controlled cohort analysis achieved good predictive accuracy across the outcomes and databases under study. The optimal design based on this reference set uses a 360 days surveillance period and a single control period 180 days prior to new prescriptions. It achieved an average AUC of 0.75 and AUC >0.70 in all but one scenario. A design with three separate control periods performed better for the electronic health records database and for acute renal failure across all data sets. The estimates for negative test cases were generally unbiased, but a minor negative bias of up to 0.2 on the RR-scale was observed with the configurations using multiple control periods, for acute liver injury and upper gastrointestinal bleeding. The calibrated self

Multidimensional Treatment Foster Care for Adolescents in English care: randomised trial and observational cohort evaluation.

PubMed

Green, J M; Biehal, N; Roberts, C; Dixon, J; Kay, C; Parry, E; Rothwell, J; Roby, A; Kapadia, D; Scott, S; Sinclair, I

2014-03-01

Children in care often have poor outcomes. There is a lack of evaluative research into intervention options. To examine the efficacy of Multidimensional Treatment Foster Care for Adolescents (MTFC-A) compared with usual care for young people at risk in foster care in England. A two-arm single (assessor) blinded randomised controlled trial (RCT) embedded within an observational quasi-experimental case-control study involving 219 young people aged 11-16 years (trial registration: ISRCTN 68038570). The primary outcome was the Child Global Assessment Scale (CGAS). Secondary outcomes were ratings of educational attendance, achievement and rate of offending. The MTFC-A group showed a non-significant improvement in CGAS outcome in both the randomised cohort (n = 34, adjusted mean difference 1.3, 95% CI -7.1 to 9.7, P = 0.75) and in the trimmed observational cohort (n = 185, adjusted mean difference 0.95, 95% CI -2.38 to 4.29, P = 0.57). No significant effects were seen in secondary outcomes. There was a possible differential effect of the intervention according to antisocial behaviour. There was no evidence that the use of MTFC-A resulted in better outcomes than usual care. The intervention may be more beneficial for young people with antisocial behaviour but less beneficial than usual treatment for those without.

Observations of Children's Interactions with Teachers, Peers, and Tasks across Preschool Classroom Activity Settings.

PubMed

Booren, Leslie M; Downer, Jason T; Vitiello, Virginia E

2012-07-01

This descriptive study examined classroom activity settings in relation to children's observed behavior during classroom interactions, child gender, and basic teacher behavior within the preschool classroom. 145 children were observed for an average of 80 minutes during 8 occasions across 2 days using the inCLASS, an observational measure that conceptualizes behavior into teacher, peer, task, and conflict interactions. Findings indicated that on average children's interactions with teachers were higher in teacher-structured settings, such as large group. On average, children's interactions with peers and tasks were more positive in child-directed settings, such as free choice. Children experienced more conflict during recess and routines/transitions. Finally, gender differences were observed within small group and meals. The implications of these findings might encourage teachers to be thoughtful and intentional about what types of support and resources are provided so children can successfully navigate the demands of particular settings. These findings are not meant to discourage certain teacher behaviors or imply value of certain classroom settings; instead, by providing an evidenced-based picture of the conditions under which children display the most positive interactions, teachers can be more aware of choices within these settings and have a powerful way to assist in professional development and interventions.

An intercomparison of observational precipitation data sets over Northwest India during winter

NASA Astrophysics Data System (ADS)

Nageswararao, M. M.; Mohanty, U. C.; Ramakrishna, S. S. V. S.; Dimri, A. P.

2018-04-01

Winter (DJF) precipitation over Northwest India (NWI) is very important for the cultivation of Rabi crops. Thus, an accurate estimation of high-resolution observations, evaluation of high-resolution numerical models, and understanding the local variability trends are essential. The objective of this study is to verify the quality of a new high spatial resolution (0.25° × 0.25°) gridded daily precipitation data set of India Meteorological Department (IMD1) over NWI during winter. An intercomparison with four existing precipitation data sets at 0.5° × 0.5° of IMD (IMD2), 1° × 1° of IMD (IMD3), 0.25° × 0.25° of APHRODITE (APRD1), and 0.5° × 0.5° of APHRODITE (APRD1) resolution during a common period of 1971-2003 is done. The evaluation of data quality of these five data sets against available 26 station observations is carried out, and the results clearly indicate that all the five data sets reasonably agreed with the station observation. However, the errors are relatively more in all the five data sets over Jammu and Kashmir-related four stations (Srinagar, Drass, Banihal top, and Dawar), while these errors are less in the other stations. It may be due to the lack of station observations over the region. The quality of IMD1 data set over NWI for winter precipitation is reasonably well than the other data sets. The intercomparison analysis suggests that the climatological mean, interannual variability, and coefficient of variation from IMD1 are similar with other data sets. Further, the analysis extended to the India meteorological subdivisions over the region. This analysis indicates overestimation in IMD3 and underestimation in APRD1 and APRD2 over Jammu and Kashmir, Himachal Pradesh, and NWI as a whole, whereas IMD2 is closer to IMD1. Moreover, all the five data sets are highly correlated (>0.5) among them at 99.9% confidence level for all subdivisions. It is remarkably noticed that multicategorical (light precipitation, moderate precipitation, heavy

Alcohol-based instant hand sanitizer use in military settings: a prospective cohort study of Army basic trainees.

PubMed

Mott, Peter J; Sisk, Brian W; Arbogast, James W; Ferrazzano-Yaussy, Cristina; Bondi, Cara A M; Sheehan, James J

2007-11-01

We investigated the impact of a customized alcohol-based instant hand sanitizer hand-hygiene regimen in an Army basic training setting. The entire population at the U.S. Army Field Artillery Training Center, Fort Sill, Oklahoma, participated in the 13-week prospective cohort study between January 18, 2005 and April 18, 2005. Two training battalions were randomly assigned to the control group, one to the primary intervention group (customized Purell Instant Hand Sanitizer regimen, education, reinforcement) and one to the secondary intervention group (customized Purell Instant Hand Sanitizer regimen). When compared to the control group, intervention groups experienced 40% less respiratory illness (p < 0.001), 48% less gastrointestinal illness (p < 0.02), 44% less lost training time (p < 0.001), and 31% fewer health care encounters (p < 0.001). These findings suggest that this intervention is capable of significantly reducing illness in this setting and has the potential to help reduce absenteeism in the military workforce as a whole.

Development of a direct observation Measure of Environmental Qualities of Activity Settings.

PubMed

King, Gillian; Rigby, Patty; Batorowicz, Beata; McMain-Klein, Margot; Petrenchik, Theresa; Thompson, Laura; Gibson, Michelle

2014-08-01

The aim of this study was to develop an observer-rated measure of aesthetic, physical, social, and opportunity-related qualities of leisure activity settings for young people (with or without disabilities). Eighty questionnaires were completed by sets of raters who independently rated 22 community/home activity settings. The scales of the 32-item Measure of Environmental Qualities of Activity Settings (MEQAS; Opportunities for Social Activities, Opportunities for Physical Activities, Pleasant Physical Environment, Opportunities for Choice, Opportunities for Personal Growth, and Opportunities to Interact with Adults) were determined using principal components analyses. Test-retest reliability was determined for eight activity settings, rated twice (4-6wk interval) by a trained rater. The factor structure accounted for 80% of the variance. The Kaiser-Meyer-Olkin Measure of Sampling Adequacy was 0.73. Cronbach's alphas for the scales ranged from 0.76 to 0.96, and interrater reliabilities (ICCs) ranged from 0.60 to 0.93. Test-retest reliabilities ranged from 0.70 to 0.90. Results suggest that the MEQAS has a sound factor structure and preliminary evidence of internal consistency, interrater, and test-retest reliability. The MEQAS is the first observer-completed measure of environmental qualities of activity settings. The MEQAS allows researchers to assess comprehensively qualities and affordances of activity settings, and can be used to design and assess environmental qualities of programs for young people. © 2014 Mac Keith Press.

Generalizability and decision studies to inform observational and experimental research in classroom settings.

PubMed

Bottema-Beutel, Kristen; Lloyd, Blair; Carter, Erik W; Asmus, Jennifer M

2014-11-01

Attaining reliable estimates of observational measures can be challenging in school and classroom settings, as behavior can be influenced by multiple contextual factors. Generalizability (G) studies can enable researchers to estimate the reliability of observational data, and decision (D) studies can inform how many observation sessions are necessary to achieve a criterion level of reliability. We conducted G and D studies using observational data from a randomized control trial focusing on social and academic participation of students with severe disabilities in inclusive secondary classrooms. Results highlight the importance of anchoring observational decisions to reliability estimates from existing or pilot data sets. We outline steps for conducting G and D studies and address options when reliability estimates are lower than desired.

Validation of the pooled cohort risk score in an Asian population - a retrospective cohort study.

PubMed

Chia, Yook Chin; Lim, Hooi Min; Ching, Siew Mooi

2014-11-20

The Pooled Cohort Risk Equation was introduced by the American College of Cardiology (ACC) and American Heart Association (AHA) 2013 in their Blood Cholesterol Guideline to estimate the 10-year atherosclerotic cardiovascular disease (ASCVD) risk. However, absence of Asian ethnicity in the contemporary cohorts and limited studies to examine the use of the risk score limit the applicability of the equation in an Asian population. This study examines the validity of the pooled cohort risk score in a primary care setting and compares the cardiovascular risk using both the pooled cohort risk score and the Framingham General Cardiovascular Disease (CVD) risk score. This is a 10-year retrospective cohort study of randomly selected patients aged 40-79 years. Baseline demographic data, co-morbidities and cardiovascular (CV) risk parameters were captured from patient records in 1998. Pooled cohort risk score and Framingham General CVD risk score for each patient were computed. All ASCVD events (nonfatal myocardial infarction, coronary heart disease (CHD) death, fatal and nonfatal stroke) occurring from 1998-2007 were recorded. A total of 922 patients were studied. In 1998, mean age was 57.5 ± 8.8 years with 66.7% female. There were 47% diabetic patients and 59.9% patients receiving anti-hypertensive treatment. More than 98% of patients with pooled cohort risk score ≥7.5% had FRS >10%. A total of 45 CVD events occurred, 22 (7.2%) in males and 23 (3.7%) in females. The median pooled cohort risk score for the population was 10.1 (IQR 4.7-20.6) while the actual ASCVD events that occurred was 4.9% (45/922). Our study showed moderate discrimination with AUC of 0.63. There was good calibration with Hosmer-Lemeshow test χ2 = 12.6, P = 0.12. The pooled cohort risk score appears to overestimate CV risk but this apparent over-prediction could be a result of treatment. In the absence of a validated score in an untreated population, the pooled cohort risk score appears to be

Effects of chlorhexidine gluconate oral care on hospital mortality: a hospital-wide, observational cohort study.

PubMed

Deschepper, Mieke; Waegeman, Willem; Eeckloo, Kristof; Vogelaers, Dirk; Blot, Stijn

2018-05-09

Chlorhexidine oral care is widely used in critically and non-critically ill hospitalized patients to maintain oral health. We investigated the effect of chlorhexidine oral care on mortality in a general hospitalized population. In this single-center, retrospective, hospital-wide, observational cohort study we included adult hospitalized patients (2012-2014). Mortality associated with chlorhexidine oral care was assessed by logistic regression analysis. A threshold cumulative dose of 300 mg served as a dichotomic proxy for chlorhexidine exposure. We adjusted for demographics, diagnostic category, and risk of mortality expressed in four categories (minor, moderate, major, and extreme). The study cohort included 82,274 patients of which 11,133 (14%) received chlorhexidine oral care. Low-level exposure to chlorhexidine oral care (≤ 300 mg) was associated with increased risk of death [odds ratio (OR) 2.61; 95% confidence interval (CI) 2.32-2.92]. This association was stronger among patients with a lower risk of death: OR 5.50 (95% CI 4.51-6.71) with minor/moderate risk, OR 2.33 (95% CI 1.96-2.78) with a major risk, and a not significant OR 1.13 (95% CI 0.90-1.41) with an extreme risk of mortality. Similar observations were made for high-level exposure (> 300 mg). No harmful effect was observed in ventilated and non-ventilated ICU patients. Increased risk of death was observed in patients who did not receive mechanical ventilation and were not admitted to ICUs. The adjusted number of patients needed to be exposed to result in one additional fatality case was 47.1 (95% CI 45.2-49.1). These data argue against the indiscriminate widespread use of chlorhexidine oral care in hospitalized patients, in the absence of proven benefit in specific populations.

Using full-cohort data in nested case-control and case-cohort studies by multiple imputation.

PubMed

Keogh, Ruth H; White, Ian R

2013-10-15

In many large prospective cohorts, expensive exposure measurements cannot be obtained for all individuals. Exposure-disease association studies are therefore often based on nested case-control or case-cohort studies in which complete information is obtained only for sampled individuals. However, in the full cohort, there may be a large amount of information on cheaply available covariates and possibly a surrogate of the main exposure(s), which typically goes unused. We view the nested case-control or case-cohort study plus the remainder of the cohort as a full-cohort study with missing data. Hence, we propose using multiple imputation (MI) to utilise information in the full cohort when data from the sub-studies are analysed. We use the fully observed data to fit the imputation models. We consider using approximate imputation models and also using rejection sampling to draw imputed values from the true distribution of the missing values given the observed data. Simulation studies show that using MI to utilise full-cohort information in the analysis of nested case-control and case-cohort studies can result in important gains in efficiency, particularly when a surrogate of the main exposure is available in the full cohort. In simulations, this method outperforms counter-matching in nested case-control studies and a weighted analysis for case-cohort studies, both of which use some full-cohort information. Approximate imputation models perform well except when there are interactions or non-linear terms in the outcome model, where imputation using rejection sampling works well. Copyright © 2013 John Wiley & Sons, Ltd.

An interactive environment for the analysis of large Earth observation and model data sets

NASA Technical Reports Server (NTRS)

Bowman, Kenneth P.; Walsh, John E.; Wilhelmson, Robert B.

1993-01-01

We propose to develop an interactive environment for the analysis of large Earth science observation and model data sets. We will use a standard scientific data storage format and a large capacity (greater than 20 GB) optical disk system for data management; develop libraries for coordinate transformation and regridding of data sets; modify the NCSA X Image and X DataSlice software for typical Earth observation data sets by including map transformations and missing data handling; develop analysis tools for common mathematical and statistical operations; integrate the components described above into a system for the analysis and comparison of observations and model results; and distribute software and documentation to the scientific community.

An interactive environment for the analysis of large Earth observation and model data sets

NASA Technical Reports Server (NTRS)

Bowman, Kenneth P.; Walsh, John E.; Wilhelmson, Robert B.

1992-01-01

We propose to develop an interactive environment for the analysis of large Earth science observation and model data sets. We will use a standard scientific data storage format and a large capacity (greater than 20 GB) optical disk system for data management; develop libraries for coordinate transformation and regridding of data sets; modify the NCSA X Image and X Data Slice software for typical Earth observation data sets by including map transformations and missing data handling; develop analysis tools for common mathematical and statistical operations; integrate the components described above into a system for the analysis and comparison of observations and model results; and distribute software and documentation to the scientific community.

Conversion of National Health Insurance Service-National Sample Cohort (NHIS-NSC) Database into Observational Medical Outcomes Partnership-Common Data Model (OMOP-CDM).

PubMed

You, Seng Chan; Lee, Seongwon; Cho, Soo-Yeon; Park, Hojun; Jung, Sungjae; Cho, Jaehyeong; Yoon, Dukyong; Park, Rae Woong

2017-01-01

It is increasingly necessary to generate medical evidence applicable to Asian people compared to those in Western countries. Observational Health Data Sciences a Informatics (OHDSI) is an international collaborative which aims to facilitate generating high-quality evidence via creating and applying open-source data analytic solutions to a large network of health databases across countries. We aimed to incorporate Korean nationwide cohort data into the OHDSI network by converting the national sample cohort into Observational Medical Outcomes Partnership-Common Data Model (OMOP-CDM). The data of 1.13 million subjects was converted to OMOP-CDM, resulting in average 99.1% conversion rate. The ACHILLES, open-source OMOP-CDM-based data profiling tool, was conducted on the converted database to visualize data-driven characterization and access the quality of data. The OMOP-CDM version of National Health Insurance Service-National Sample Cohort (NHIS-NSC) can be a valuable tool for multiple aspects of medical research by incorporation into the OHDSI research network.

Reviewing long-term antidepressants can reduce drug burden: a prospective observational cohort study

PubMed Central

Johnson, Chris F; Macdonald, Hector J; Atkinson, Pauline; Buchanan, Alasdair I; Downes, Noreen; Dougall, Nadine

2012-01-01

Background Antidepressant prescribing continues to rise. Contributing factors are increased long-term prescribing and possibly the use of higher selective serotonin re-uptake inhibitor (SSRI) doses. Aim To review general practice patients prescribed the same antidepressant long-term (≥2 years) and evaluate prescribing and management pre and post-review. Design and setting Prospective observational cohort study using routine data from 78 urban general practices, Scotland. Method All patients prescribed antidepressants (excluding amitriptyline) for ≥2 years were identified from records November 2009 to March 2010. GPs selected patients for face-to-face review of clinical condition and medication, December 2009 to September 2010. Pre- and post-review data were collected; average antidepressant doses and changes in prescribed daily doses were calculated. Onward referral to support services was recorded. Results 8.6% (33 312/388 656) of all registered patients were prescribed an antidepressant, 47.1% (15 689) were defined as long-term users and 2849 (18.2%) were reviewed. 811 (28.5%) patients reviewed had a change in antidepressant therapy: 7.0% stopped, 12.8% reduced dose, 5.3% increased dose, and 3.4% changed antidepressant, resulting in 9.5% (95% CI = 9.1% to 9.8% P<0.001) reduction in prescribed daily dose and 8.1% reduction in prescribing costs. 6.3% were referred onwards, half to NHS Mental Health Services. Pre-review SSRI doses were 10–30% higher than previously reported. Conclusion Almost half of all people prescribed antidepressants were long-term users. Appropriate reductions in prescribing can be achieved by reviewing patients. Higher SSRI doses may be contributing to current antidepressant growth. PMID:23211181

Statins and secondary prevention of venous thromboembolism: pooled analysis of published observational cohort studies.

PubMed

Kunutsor, Setor K; Seidu, Samuel; Khunti, Kamlesh

2017-05-21

There have been suggestions that statins may have a potential role in secondary prevention of venous thromboembolism (VTE) [which includes deep vein thrombosis (DVT) and pulmonary embolism (PE)], but the evidence is inconsistent. We aimed to evaluate the association between statin use and risk of recurrent VTE. We conducted a systematic review and meta-analysis of observational cohort studies. All relevant studies which reported associations between statin use and recurrent VTE outcomes were identified from MEDLINE, EMBASE, Web of Science, and manual search of bibliographies from inception to January 2017. Study specific relative risks (RRs) with 95% confidence intervals were aggregated using random effects models. Eight eligible studies comprising of 103 576 participants and 13 168 recurrent VTE outcomes were included in the pooled analysis. In pooled analysis of 7 studies, the RR for recurrent VTE was 0.73 (0.68-0.79) when comparing statin use with no use. There was no evidence of heterogeneity between contributing studies (I2=0%, 0-71%; P = 0.93). The RRs for recurrent PE (three studies) and DVT (two studies) comparing statin use with no statin use were 0.75 (95% CI: 0.58-0.96) and 0.66 (95% CI: 0.60-0.71) respectively. Available evidence from observational cohort studies suggests a beneficial effect of statin use on VTE recurrence. Well-designed intervention studies are needed to corroborate these findings. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For permissions, please email: journals.permissions@oup.com.

Generalizability and Decision Studies to Inform Observational and Experimental Research in Classroom Settings

ERIC Educational Resources Information Center

Bottema-Beutel, Kristen; Lloyd, Blair; Carter, Erik W.; Asmus, Jennifer M.

2014-01-01

Attaining reliable estimates of observational measures can be challenging in school and classroom settings, as behavior can be influenced by multiple contextual factors. Generalizability (G) studies can enable researchers to estimate the reliability of observational data, and decision (D) studies can inform how many observation sessions are…

[Quality standards for epidemiologic cohort studies : An evaluated catalogue of requirements for the conduct and preparation of cohort studies].

PubMed

Schmidt, Carsten Oliver; Krabbe, Christine E M; Schössow, Janka; Berger, Klaus; Enzenbach, Cornelia; Kamtsiuris, Panagiotis; Schöne, Gina; Houben, Robin; Meisinger, Christa; Bamberg, Fabian; Hendel, Thomas; Selder, Sonja; Nonnemacher, Michael; Moebus, Susanne; Stausberg, Jürgen

2018-01-01

Cohort studies are a longitudinal observational study type. They are firmly established within epidemiology to assess the course of diseases and risk factors. Yet, standards to describe and evaluate quality characteristics of cohort studies need further development. Within the TMF ("Technologie- und Methodenplattform für die vernetzte medizinische Forschung e. V.") project "Quality management standards in cohort studies", a catalogue of requirements was compiled and evaluated, focusing on the preparation and conduct of epidemiologic cohort studies. The catalogue of requirements was established based on a consensus process between representatives of seven German epidemiologic cohort studies. For this purpose, a set of expert meetings (telephone, face-to-face, web-based) was conducted and the importance of each element of the catalogue was assessed as well as its implementation. A catalogue of requirements with 138 requirements was consented. It is structured into ten sections: 1. Study documentation; 2. Selection of instruments; 3. Study implementation, 4. Organizational structure; 5. Qualification and certification; 6. Participant recruitment; 7. Preparation, conduct and follow-up processing of examinations; 8. Study logistics and maintenance, 9. Data capture and data management; 10. Reporting and monitoring. In total, 41 elements were categorized as being essential, 91 as important, and 6 as less important. The catalogue of requirements provides a guideline to improve the preparation and operation of cohort studies. The evaluation of the importance and degree of implementation of requirements depended on the study design. With adaptations, the catalogue might be transferable to other study types.

Cesarean Outcomes in US Birth Centers and Collaborating Hospitals: A Cohort Comparison.

PubMed

Thornton, Patrick; McFarlin, Barbara L; Park, Chang; Rankin, Kristin; Schorn, Mavis; Finnegan, Lorna; Stapleton, Susan

2017-01-01

High rates of cesarean birth are a significant health care quality issue, and birth centers have shown potential to reduce rates of cesarean birth. Measuring this potential is complicated by lack of randomized trials and limited observational comparisons. Cesarean rates vary by provider type, setting, and clinical and nonclinical characteristics of women, but our understanding of these dynamics is incomplete. We sought to isolate labor setting from other risk factors in order to assess the effect of birth centers on the odds of cesarean birth. We generated low-risk cohorts admitted in labor to hospitals (n = 2527) and birth centers (n = 8776) using secondary data obtained from the American Association of Birth Centers (AABC). All women received prenatal care in the birth center and midwifery care in labor, but some chose hospital admission for labor. Analysis was intent to treat according to site of admission in spontaneous labor. We used propensity score adjustment and multivariable logistic regression to control for cohort differences and measured effect sizes associated with setting. There was a 37% (adjusted odds ratio [OR], 0.63; 95% confidence interval [CI], 0.50-0.79) to 38% (adjusted OR, 0.62; 95% CI, 0.49-0.79) decreased odds of cesarean in the birth center cohort and a remarkably low overall cesarean rate of less than 5% in both cohorts. These findings suggest that low rates of cesarean in birth centers are not attributable to labor setting alone. The entire birth center care model, including prenatal preparation and relationship-based midwifery care, should be studied, promoted, and implemented by policy makers interested in achieving appropriate cesarean rates in the United States. © 2016 by the American College of Nurse-Midwives.

Observations of Children’s Interactions with Teachers, Peers, and Tasks across Preschool Classroom Activity Settings

PubMed Central

Booren, Leslie M.; Downer, Jason T.; Vitiello, Virginia E.

2014-01-01

This descriptive study examined classroom activity settings in relation to children’s observed behavior during classroom interactions, child gender, and basic teacher behavior within the preschool classroom. 145 children were observed for an average of 80 minutes during 8 occasions across 2 days using the inCLASS, an observational measure that conceptualizes behavior into teacher, peer, task, and conflict interactions. Findings indicated that on average children’s interactions with teachers were higher in teacher-structured settings, such as large group. On average, children’s interactions with peers and tasks were more positive in child-directed settings, such as free choice. Children experienced more conflict during recess and routines/transitions. Finally, gender differences were observed within small group and meals. The implications of these findings might encourage teachers to be thoughtful and intentional about what types of support and resources are provided so children can successfully navigate the demands of particular settings. These findings are not meant to discourage certain teacher behaviors or imply value of certain classroom settings; instead, by providing an evidenced-based picture of the conditions under which children display the most positive interactions, teachers can be more aware of choices within these settings and have a powerful way to assist in professional development and interventions. PMID:25717282

An Innovative Model for Naloxone Use Within an OTP Setting: A Prospective Cohort Study

PubMed Central

Katzman, Joanna G.; Takeda, Mikiko Y.; Bhatt, Snehal R.; Moya Balasch, Monica; Greenberg, Nina; Yonas, Howard

2018-01-01

Objectives: Unintentional opioid overdose deaths are a public health crisis, and naloxone is the most effective harm reduction tool to curb many of these deaths. There is growing evidence that take-home naloxone can prevent opioid overdose in targeted populations. The goal of this study is to measure the opioid overdose reversal rate with take-home naloxone among participants with a diagnosis of opioid use disorder (OUD) in an opioid treatment program (OTP) setting. Methods: Patients enrolled in an outpatient OTP program were eligible for this prospective cohort study between April 4, 2016 and July 4, 2016. Two hundred forty-four study participants received overdose education, instruction on how to use naloxone, and were provided with 2 doses of a take-home naloxone auto-injector kit. They were subsequently followed for 3 months. Results: Thirty-one study participants reported overdose reversals using naloxone auto-injector kits on 38 community members. All overdose reversals were heroin-related. Eighty-seven per cent of the community members reversed with naloxone were friends or relatives of the study participants. Conclusions: This study validates that naloxone is not commonly used on the index study participant, but is often used on a secondary target among people who inject drugs. The large number of overdose reversals reported in this prospective study suggests that this novel model for naloxone use may be replicated at other OTP settings to reduce opioid overdose deaths. PMID:29227321

Utilisation and Safety of Deferasirox: Results from an Observational Cohort Study in England.

PubMed

Osborne, Vicki; Davies, Miranda; Layton, Deborah; Shakir, Saad A W

2018-03-01

Deferasirox (EXJADE ® , Novartis, UK) is an oral iron-chelating agent primarily used to reduce chronic iron overload in patients receiving blood transfusions for various chronic anaemias and some non-transfusion dependant anaemias. The aim of this study was to examine the utilisation and safety of deferasirox used in general practice in England. A single exposure observational cohort study design was used. Patients were identified from dispensed prescriptions for deferasirox between September 2006 and September 2014. Outcome data were collected via postal questionnaires sent to prescribers ≥ 6 months after first dispensed prescription for an individual patient. Summary descriptive statistics were calculated. The evaluable cohort consisted of 122 patients, of which 41.8% were aged 2-17 years. Frequent reasons for prescribing were sickle cell anaemia (27/103 where specified, 26.2%) and beta thalassaemia (26, 25.2%). The majority of patients (43/51, 84.3%) were prescribed the licensed doses of 10 or 20 mg/kg/day at start. Prior measurements of serum creatinine were only reported for a small proportion this study (18/122, 14.8%). In total, 91 incident events were reported, including two of raised serum creatinine. These results show that deferasirox is largely being prescribed for its licensed indications in general practice in England and events reported were consistent with the known safety profile.

Assessing the order of magnitude of outcomes in single-arm cohorts through systematic comparison with corresponding cohorts: An example from the AMOS study

PubMed Central

Hamre, Harald J; Glockmann, Anja; Tröger, Wilfried; Kienle, Gunver S; Kiene, Helmut

2008-01-01

Background When a therapy has been evaluated in the first clinical study, the outcome is often compared descriptively to outcomes in corresponding cohorts receiving other treatments. Such comparisons are often limited to selected studies, and often mix different outcomes and follow-up periods. Here we give an example of a systematic comparison to all cohorts with identical outcomes and follow-up periods. Methods The therapy to be compared (anthroposophic medicine, a complementary therapy system) had been evaluated in one single-arm cohort study: the Anthroposophic Medicine Outcomes Study (AMOS). The five largest AMOS diagnosis groups (A-cohorts: asthma, depression, low back pain, migraine, neck pain) were compared to all retrievable corresponding cohorts (C-cohorts) receiving other therapies with identical outcomes (SF-36 scales or summary measures) and identical follow-up periods (3, 6 or 12 months). Between-group differences (pre-post difference in an A-cohort minus pre-post difference in the respective C-cohort) were divided with the standard deviation (SD) of the baseline score of the A-cohort. Results A-cohorts (5 cohorts with 392 patients) were similar to C-cohorts (84 cohorts with 16,167 patients) regarding age, disease duration, baseline affection and follow-up rates. A-cohorts had ≥ 0.50 SD larger improvements than C-cohorts in 13.5% (70/517) of comparisons; improvements of the same order of magnitude (small or minimal differences: -0.49 to 0.49 SD) were found in 80.1% of comparisons; and C-cohorts had ≥ 0.50 SD larger improvements than A-cohorts in 6.4% of comparisons. Analyses stratified by diagnosis had similar results. Sensitivity analyses, restricting the comparisons to C-cohorts with similar study design (observational studies), setting (primary care) or interventions (drugs, physical therapies, mixed), or restricting comparisons to SF-36 scales with small baseline differences between A- and C-cohorts (-0.49 to 0.49 SD) also had similar results

Nested Cohort - R software package

Cancer.gov

NestedCohort is an R software package for fitting Kaplan-Meier and Cox Models to estimate standardized survival and attributable risks for studies where covariates of interest are observed on only a sample of the cohort.

New graduate separations from New Zealand's nursing workforce in the first 5 years after registration: a retrospective cohort analysis of a national administrative data set 2005-2010.

PubMed

North, Nicola; Leung, William; Lee, Rochelle

2014-08-01

To describe workforce separation rates and its relationship with demographic and work characteristics in the 2005 new graduate cohort's first 5 years as practising RNs in NZ. Retaining new graduate RNs is critical to nursing workforce sustainability; one study showed that if an RN is still employed in a hospital setting 5 years after graduation, he/she tends to remain active in the health industry. Retrospective analysis using the Nursing Council of New Zealand's registration data set for years 2005-2010. All newly registered NZ graduates practising in NZ in 2005 (n = 1236) were tracked for 5 years. Within 5 years of graduation, 26% of the cohort had separated from the NZ nursing workforce, 18% in the first year. The under-25s (n = 517), 42% of the cohort, had the highest loss, 32%, in 5 years. Separations were significantly lower for graduates in their 30s vs. their 20s and for those who gained postgraduate tertiary qualifications post-registration (10%) vs. those who did not (29%). Hospitals were the most frequent employment setting over 5 years, the largest increase being community settings. Five-year retention rates in the four largest practice areas were surgical 26%, medical 16%, mental health 60% and continuing care 10%. After 5 years, 24% of those still practising (n = 920) worked in a different health board region. New graduate RN losses were higher than in previous research, with younger RNs at most risk, threatening future sustainability of the nursing workforce and highlighting the need for evidence-based targeted strategies to retain them. © 2013 John Wiley & Sons Ltd.

Research on Natural Settings: Observing Adolescent Mothers and Infants throughout the First Postpartum Year.

PubMed

Diniz, Eva; Koller, Silvia H

2018-03-01

This manuscript aims to present and discuss challenges regarding naturalistic observation of adolescent mothers and their infants throughout the first postpartum year. Case illustrations were the object to discuss methodological options and issues faced during an observational and longitudinal research. The participants live in vulnerability in a metropolitan area in Southern Brazil. Data collection challenges led to reflections about naturalistic observation and methodological procedures, which were affected by setting characteristics and by the need of adapting to them. Most methodological difficulties were linked to naturalistic observations of mothers and their infants. Personal and contextual aspects of these settings must be taken into account in order to enhance result reliability and the knowledge about cultural idiosyncrasies.

Observations in public settings

Treesearch

Robert G. Lee

1977-01-01

Straightforward observation of children in their everyday environments is a more appropriate method of discovering the meaning of their relationships to nature than complex methodologies or reductionist commonsense thinking. Observational study requires an explicit conceptual framework and adherence to procedures that allow scientific inference. Error may come from...

The Role of Preference on Outcomes of People Receiving Evidence-Informed Community Wound Care in Their Home or in a Nurse-Clinic Setting: A Cohort Study (n = 230).

PubMed

Harrison, Margaret B; VanDenKerkhof, Elizabeth G; Hopman, Wilma M; Carley, Meg E

2014-09-19

This study followed a cohort of community-dwelling individuals receiving wound-care in a large urban-rural region. During a randomized control trial (RCT) evaluating outcomes of receiving care in a nurse-clinic or at home, many approached were willing to participate if they could choose their location of care. This provided a unique opportunity to enroll them as a "choice" cohort, following them in the same manner as the trial participants but allowing them to select their setting of care. The objective was to investigate the role of preference and location of care on care outcomes, including satisfaction with care, healing, health-related quality of life (HRQL), pain, and resource use. This is a secondary analysis of a prospective cohort of 126 individuals enrolled in an RCT to receive care at home or in a nurse-clinic (Allocated group), and an additional 104 who received care at home or in a nurse-clinic based on their preference (Choice group). Mobile individuals with a leg ulcer of venous or mixed venous etiology, referred for community leg ulcer care, were eligible. Specially-trained nurses provided care to both groups using an evidence-informed protocol. Baseline data included socio-demographic, circumstance-of-living and a detailed wound assessment. Mean age of the cohort was 68 years. Satisfaction, healing, recurrence, pain, HRQL, and resource utilization did not differ between groups. If available, individuals should have an option of care venue given almost half of those approached indicated a clear preference for clinic or home. With outcomes being similar, health care planners and decision-makers, as well as individuals and their families, can feel confident that the setting of care will not impact the outcomes. However, larger studies in other contexts are needed to explore the interaction between choice and setting.

Returning findings within longitudinal cohort studies: the 1958 birth cohort as an exemplar.

PubMed

Wallace, Susan E; Walker, Neil M; Elliott, Jane

2014-01-01

Population-based, prospective longitudinal cohort studies are considering the issues surrounding returning findings to individuals as a result of genomic and other medical research studies. While guidance is being developed for clinical settings, the process is less clear for those conducting longitudinal research. This paper discusses work conducted on behalf of The UK Cohort and Longitudinal Study Enhancement Resource programme (CLOSER) to examine consent requirements, process considerations and specific examples of potential findings in the context of the 1958 British Birth cohort. Beyond deciding which findings to return, there are questions of whether re-consent is needed and the possible impact on the study, how the feedback process will be managed, and what resources are needed to support that process. Recommendations are made for actions a cohort study should consider taking when making vital decisions regarding returning findings. Any decisions need to be context-specific, arrived at transparently, communicated clearly, and in the best interests of both the participants and the study.

Cohort profile: the Healthy Life in an Urban Setting (HELIUS) study in Amsterdam, The Netherlands

PubMed Central

Snijder, Marieke B; Galenkamp, Henrike; Prins, Maria; Derks, Eske M; Peters, Ron J G; Zwinderman, Aeilko H; Stronks, Karien

2017-01-01

Purpose Ethnic minority groups usually have a more unfavourable disease risk profile than the host population. In Europe, ethnic inequalities in health have been observed in relatively small studies, with limited possibilities to explore underlying causes. The aim of the Healthy Life in an Urban Setting (HELIUS) study is to investigate the causes of (the unequal burden of) diseases across ethnic groups, focusing on three disease categories: cardiovascular diseases, mental health and infectious diseases. Participants The HELIUS study is a prospective cohort study among six large ethnic groups living in Amsterdam, the Netherlands. Between 2011 and 2015, a total 24 789 participants (aged 18–70 years) were included at baseline. Similar-sized samples of individuals of Dutch, African Surinamese, South-Asian Surinamese, Ghanaian, Turkish and Moroccan origin were included. Participants filled in an extensive questionnaire and underwent a physical examination that included the collection of biological samples (biobank). Findings to date Data on physical, behavioural, psychosocial and biological risk factors, and also ethnicity-specific characteristics (eg, culture, migration history, ethnic identity, socioeconomic factors and discrimination) were collected, as were measures of health outcomes (cardiovascular, mental health and infections). The first results have confirmed large inequalities in health between ethnic groups, such as diabetes and depressive symptoms, and also early markers of disease such as arterial wave reflection and chronic kidney disease, which can only just partially be explained by inequalities in traditional risk factors, such as obesity and socioeconomic status. In addition, the first results provided important clues for targeting prevention and healthcare. Future plans HELIUS will be used for further research on the underlying causes of ethnic differences in health. Follow-up data will be obtained by repeated measurements and by linkages with

Manual cleaning of hospital mattresses: an observational study comparing high- and low-resource settings.

PubMed

Hopman, J; Hakizimana, B; Meintjes, W A J; Nillessen, M; de Both, E; Voss, A; Mehtar, S

2016-01-01

Hospital-associated infections (HAIs) are more frequently encountered in low- than in high-resource settings. There is a need to identify and implement feasible and sustainable approaches to strengthen HAI prevention in low-resource settings. To evaluate the biological contamination of routinely cleaned mattresses in both high- and low-resource settings. In this two-stage observational study, routine manual bed cleaning was evaluated at two university hospitals using adenosine triphosphate (ATP). Standardized training of cleaning personnel was achieved in both high- and low-resource settings. Qualitative analysis of the cleaning process was performed to identify predictors of cleaning outcome in low-resource settings. Mattresses in low-resource settings were highly contaminated prior to cleaning. Cleaning significantly reduced biological contamination of mattresses in low-resource settings (P < 0.0001). After training, the contamination observed after cleaning in both the high- and low-resource settings seemed comparable. Cleaning with appropriate type of cleaning materials reduced the contamination of mattresses adequately. Predictors for mattresses that remained contaminated in a low-resource setting included: type of product used, type of ward, training, and the level of contamination prior to cleaning. In low-resource settings mattresses were highly contaminated as noted by ATP levels. Routine manual cleaning by trained staff can be as effective in a low-resource setting as in a high-resource setting. We recommend a multi-modal cleaning strategy that consists of training of domestic services staff, availability of adequate time to clean beds between patients, and application of the correct type of cleaning products. Copyright © 2015 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Design and conduct of Caudwell Xtreme Everest: an observational cohort study of variation in human adaptation to progressive environmental hypoxia

PubMed Central

2010-01-01

Background The physiological responses to hypoxaemia and cellular hypoxia are poorly understood, and inter-individual differences in performance at altitude and outcome in critical illness remain unexplained. We propose a model for exploring adaptation to hypoxia in the critically ill: the study of healthy humans, progressively exposed to environmental hypobaric hypoxia (EHH). The aim of this study was to describe the spectrum of adaptive responses in humans exposed to graded EHH and identify factors (physiological and genetic) associated with inter-individual variation in these responses. Methods Design Observational cohort study of progressive incremental exposure to EHH. Setting University human physiology laboratory in London, UK (75 m) and 7 field laboratories in Nepal at 1300 m, 3500 m, 4250 m, 5300 m, 6400 m, 7950 m and 8400 m. Participants 198 healthy volunteers and 24 investigators trekking to Everest Base Camp (EBC) (5300 m). A subgroup of 14 investigators studied at altitudes up to 8400 m on Everest. Main outcome measures Exercise capacity, exercise efficiency and economy, brain and muscle Near Infrared Spectroscopy, plasma biomarkers (including markers of inflammation), allele frequencies of known or suspected hypoxia responsive genes, spirometry, neurocognitive testing, retinal imaging, pupilometry. In nested subgroups: microcirculatory imaging, muscle biopsies with proteomic and transcriptomic tissue analysis, continuous cardiac output measurement, arterial blood gas measurement, trans-cranial Doppler, gastrointestinal tonometry, thromboelastography and ocular saccadometry. Results Of 198 healthy volunteers leaving Kathmandu, 190 reached EBC (5300 m). All 24 investigators reached EBC. The completion rate for planned testing was more than 99% in the investigator group and more than 95% in the trekkers. Unique measurements were safely performed at extreme altitude, including the highest (altitude) field measurements of exercise capacity, cerebral blood

Observation of Pupils and Teachers in Mainstream and Special Education Settings: Alternative Strategies.

ERIC Educational Resources Information Center

Weinberg, Richard A., Ed.; Wood, Frank H., Ed.

Presented are 12 papers which focus on four systematized methods of classroom observation. Stressed is the importance of formal, systematic observation as a tool for viewing and recording pupil behaviors and insuring that the individual child's needs are met in both the mainstream and special education settings. R. Brandt offers an historical…

Cohort profile: seek, test, treat and retain United States criminal justice cohort.

PubMed

Chandler, Redonna; Gordon, Michael S; Kruszka, Bridget; Strand, Lauren N; Altice, Frederick L; Beckwith, Curt G; Biggs, Mary L; Cunningham, William; Chris Delaney, J A; Flynn, Patrick M; Golin, Carol E; Knight, Kevin; Kral, Alex H; Kuo, Irene; Lorvick, Jennifer; Nance, Robin M; Ouellet, Lawrence J; Rich, Josiah D; Sacks, Stanley; Seal, David; Spaulding, Anne; Springer, Sandra A; Taxman, Faye; Wohl, David; Young, Jeremy D; Young, Rebekah; Crane, Heidi M

2017-05-16

The STTR treatment cascade provides a framework for research aimed at improving the delivery of services, care and outcomes of PLWH. The development of effective approaches to increase HIV diagnoses and engage PLWH in subsequent steps of the treatment cascade could lead to earlier and sustained ART treatment resulting in viral suppression. There is an unmet need for research applying the treatment cascade to improve outcomes for those with criminal justice involvement. The Seek, Test, Treat, and Retain (STTR) criminal justice (CJ) cohort combines data from 11 studies across the HIV treatment cascade that focused on persons involved in the criminal justice system, often but not exclusively for reasons related to substance use. The studies were conducted in a variety of CJ settings and collected information across 11 pre-selected domains: demographic characteristics, CJ involvement, HIV risk behaviors, HIV and/or Hepatitis C infections, laboratory measures of CD4 T-cell count (CD4) and HIV RNA viral load (VL), mental illness, health related quality of life (QoL), socioeconomic status, health care access, substance use, and social support. The STTR CJ cohort includes data on 11,070 individuals with and without HIV infection who range in age from 18 to 77 years, with a median age at baseline of 37 years. The cohort reflects racial, ethnic and gender distributions in the U.S. CJ system, and 64% of participants are African-American, 12% are Hispanic and 83% are men. Cohort members reported a wide range of HIV risk behaviors including history of injection drug use and, among those who reported on pre-incarceration sexual behaviors, the prevalence of unprotected sexual intercourse ranged across studies from 4% to 79%. Across all studies, 53% percent of the STTR CJ cohort reported recent polysubstance use. The STTR CJ cohort is comprised of participants from a wide range of CJ settings including jail, prison, and community supervision who report considerable diversity in

Observational longitudinal cohort study to determine progression to heart failure in a screened community population: the Echocardiographic Heart of England Screening Extension (ECHOES-X) study

PubMed Central

Taylor, Clare J; Roalfe, Andrea K; Tait, Lynda; Davis, Russell C; Iles, Rachel; Derit, Marites; Hobbs, F D Richard

2014-01-01

Objectives Rescreen a large community cohort to examine the progression to heart failure over time and the role of natriuretic peptide testing in screening. Design Observational longitudinal cohort study. Setting 16 socioeconomically diverse practices in central England. Participants Participants from the original Echocardiographic Heart of England Screening (ECHOES) study were invited to attend for rescreening. Outcome measures Prevalence of heart failure at rescreening overall and for each original ECHOES subgroup. Test performance of N Terminal pro-B-type Natriuretic Peptide (NT-proBNP) levels at different thresholds for screening. Results 1618 of 3408 participants underwent screening which represented 47% of survivors and 26% of the original ECHOES cohort. A total of 176 (11%, 95% CI 9.4% to 12.5%) participants were classified as having heart failure at rescreening; 103 had heart failure with reduced ejection fraction (HFREF) and 73 had heart failure with preserved ejection fraction (HFPEF). Sixty-eight out of 1232 (5.5%, 95% CI 4.3% to 6.9%) participants who were recruited from the general population over the age of 45 and did not have heart failure in the original study, had heart failure on rescreening. An NT-proBNP cut-off of 400 pg/mL had sensitivity for a diagnosis of heart failure of 79.5% (95% CI 72.4% to 85.5%) and specificity of 87% (95% CI 85.1% to 88.8%). Conclusions Rescreening identified new cases of HFREF and HFPEF. Progression to heart failure poses a significant threat over time. The natriuretic peptide cut-off level for ruling out heart failure must be low enough to ensure cases are not missed at screening. PMID:25015472

Treatment of Patients With Hepatitis C Virus Infection With Ledipasvir-Sofosbuvir in the Liver Transplant Setting.

PubMed

Abaalkhail, Faisal; Elsiesy, Hussein; Elbeshbeshy, Hany; Shawkat, Mohamed; Yousif, Sarra; Ullah, Waheed; Alabbad, Saleh; Al-Jedai, Ahmed; Ajlan, Aziza; Broering, Dieter; Saab, Sammy; Al Sebayel, Mohammed; Al-Hamoudi, Waleed

2017-11-01

Hepatitis C virus (HCV) infection is a major cause of liver cirrhosis and hepatocellular carcinoma and the leading indication for liver transplantation. In the Middle East, genotype 4 HCV infection is the most common genotype. However, limited data exists on the treatment of genotype-4 in the liver transplant setting. We evaluated the safety and efficacy of ledipasvir (LDV)-sofosbuvir (SOF) in treating HCV genotype-4 infected patients with cirrhosis or postliver transplantation. This prospective, single-arm, observational study includes cohort of patients with cirrhosis before liver transplantation (cohort A) and a cohort of postliver transplantation patients (cohort B). Patients received LDV/SOF (90-400 mg) once daily for 12 to 24 weeks with or without ribavirin (RBV). Patients with creatinine clearance below 30 were excluded. A total of 111 patients (61 cirrhotic; 50 postliver transplants) with HCV genotype 4 were treated in King Faisal Specialist Hospital and Research Center; 55% cohort A and 44% cohort B received RBV. Sustained virological response sustain virological response (SVR)12 was 91.8% and 86% of cohorts A and B, respectively. There were no treatment-related mortality or serious adverse effects. RBV dose reduction occurred in 25% without any treatment discontinuation. SVR12 rates in cohort A were significantly higher in patients with a viral load below 800 000 (100% vs 83.9%, P value = 0.022). Viral load did not impact SVR rates in cohort B. The use of RBV did not increase SVR12 and was associated with anemia. LDV/SOF without RBV is an effective and safe treatment option for patients with HCV genotype 4 infection in preliver and postliver transplant settings.

Mechanical versus manual manipulation for low back pain: An observational cohort study

PubMed Central

Schneider, Michael J; Brach, Jennifer; Irrgang, James J.; Abbott, Katherine Verdolini; Wisniewski, Stephen R.; Delitto, Anthony

2010-01-01

Objective This is an observational prospective cohort study to explore the treatment effect of mechanical vs. manual manipulation for acute low back pain. Methods Ninety two patients with a history of acute low back pain were recruited from 3 private chiropractic offices, 2 of which utilized manual lumbar manipulation and 1 used mechanical instrument manipulation (Activator) as their primary modes of treatment. The chiropractors used their “treatment as usual” protocols for a maximum of 8 visits or 4 weeks, which ever occurred first. Primary outcome measures were changes in Numeric Pain Rating Scale (NPRS) and Oswestry Disability Index (ODI) scores from baseline to 4 weeks. The linear regression models were adjusted for baseline NPRS and ODI scores, age, and treatment expectancy. Results Comparison of baseline characteristics did not show any significant differences between the groups except for age (38.4 vs. 49.7 years; p < .001) and treatment expectancy (5.7 vs. 6.3; p = .003). Linear regression revealed significantly lower NPRS scores in the manual manipulation group at four weeks [β = −1.2; 95% CI (−2.1, −.28)] but no significant difference in ODI scores between the two groups at four weeks [β = 1.5; 95% CI (−8.3, 2.4)]. Treatment expectancy, but not age, was found to have a significant main effect on both NPRS and ODI scores at 4 weeks. Exploratory analysis of the clinical patterns of care between the clinicians revealed significant differences in treatment frequency, duration, modality and radiograph usage between the 2 cohorts. Conclusions This study highlights the challenges inherent with conducting research that allows for “treatment-as-usual”. The data and experience derived from this investigational study will be used to design a future randomized clinical trial in which tighter controls will be imposed on the treatment protocol. PMID:20350672

Observational Cohort Study of Pregnancy Outcome after First-Trimester Exposure to Fluoroquinolones

PubMed Central

Wacker, Evelin; Meister, Reinhard; Panse, Mary; Weber-Schoendorfer, Corinna; Oppermann, Marc; Schaefer, Christof

2014-01-01

Fluoroquinolones are avoided during pregnancy due to developmental toxicity in animals. The aim of this study was to assess the fetal risk after intrauterine fluoroquinolone exposure. We performed an observational study of a prospectively ascertained cohort of pregnant women exposed to a fluoroquinolone during the first trimester. Pregnancy outcomes were compared to those of a cohort exposed to neither fluoroquinolones nor teratogenic or fetotoxic drugs. The outcomes evaluated were major birth defects (structural abnormalities of medical, surgical, or cosmetic relevance), spontaneous abortion, and elective termination of pregnancy. Pregnancy outcomes of 949 women with fluoroquinolone treatment were compared with those of 3,796 nonexposed controls. Neither the rate of major birth defects (2.4%; adjusted odds ratio [ORadj], 0.91; 95% confidence interval [CI], 0.6 to 1.5) nor the risk of spontaneous abortion (adjusted hazard ratio [HRadj], 1.01; 95% CI, 0.8 to 1.3) was increased. However, there was a nonsignificant increase in major birth defects after exposure to moxifloxacin (6/93, 6.5%; crude odds ratio [ORcrude], 2.40; 95% CI, 0.8 to 5.6). Neither a critical exposure time window within the first trimester nor a specific pattern of birth defects was demonstrated for any of the fluoroquinolones. The rate of electively terminated pregnancies was increased among the fluoroquinolone-exposed women (HRadj, 1.32; 95% CI, 1.03 to 1.7). The gestational ages at delivery and birth weights did not differ between groups. Our study did not detect an increased risk of spontaneous abortion or major birth defects. These reassuring findings support the recommendation to allow fluoroquinolone use in early pregnancy in selected cases. After the use of moxifloxacin, a detailed fetal ultrasound examination should be considered. PMID:24841264

Does psychedelic drug use reduce risk of suicidality? Evidence from a longitudinal community-based cohort of marginalised women in a Canadian setting

PubMed Central

Argento, Elena; Strathdee, Steffanie A; Tupper, Kenneth; Braschel, Melissa; Wood, Evan; Shannon, Kate

2017-01-01

Objective This study aimed to longitudinally investigate whether ever having used a psychedelic drug can have a protective effect on incidence of suicidality among marginalised women. Design Longitudinal community-based cohort study. Setting Data were drawn from a prospective, community-based cohort of marginalised women in Metro Vancouver, Canada. Participants 766 women completed the baseline questionnaire between January 2010 and August 2014. Participants who did not report suicidality at baseline and who completed at least one follow-up visit were included. Main outcome measure Extended Cox regression was used to model predictors of new suicidality (suicide ideation or attempts) over 54-month follow-up. Results Nearly half (46%; n=355) of participants reported prior suicidality and were thus excluded from the present analyses. Of 290 women eligible at baseline, 11% (n=31) reported recent suicidality during follow-up, with an incidence density of 4.42 per 100 person-years (95% CI 3.10 to 6.30). In multivariable analysis, reported lifetime psychedelic drug use was associated with a 60% reduced hazard for suicidality (adjusted HR (AHR) 0.40; 95% CI 0.17 to 0.94). Crystal methamphetamine use (AHR 3.25; 95% CI 1.47 to 7.21) and childhood abuse (AHR 3.54; 95% CI 1.49 to 8.40) remained independent predictors of suicidality. Conclusion The high rate of suicidality identified in this study is of major concern. Alongside emerging evidence on the potential of psychedelic-assisted therapy to treat some mental illness and addiction issues, our findings demonstrate that naturalistic psychedelic drug use is independently associated with reduced suicidality, while other illicit drug use and childhood trauma predispose women to suicidality. While observational, this study supports calls for further investigation of the therapeutic utility of psychedelic drugs in treating poor mental health and promoting mental wellness. PMID:28939573

A patient cohort on long-term sequelae of sepsis survivors: study protocol of the Mid-German Sepsis Cohort.

PubMed

Scherag, André; Hartog, Christiane S; Fleischmann, Carolin; Ouart, Dominique; Hoffmann, Franziska; König, Christian; Kesselmeier, Miriam; Fiedler, Sandra; Philipp, Monique; Braune, Anke; Eichhorn, Cornelia; Gampe, Christin; Romeike, Heike; Reinhart, Konrad

2017-08-23

An increasing number of patients survive sepsis; however, we lack valid data on the long-term impact on morbidity from prospective observational studies. Therefore, we designed an observational cohort to quantify mid-term and long-term functional disabilities after intensive care unit (ICU)-treated sepsis. Ultimately, findings for the Mid-German Sepsis Cohort (MSC) will serve as basis for the implementation of follow-up structures for patients with sepsis and help to increase quality of care for sepsis survivors. All patients surviving ICU-treated sepsis are eligible and are recruited from five study centres in Germany (acute care hospital setting in Jena, Halle/Saale, Leipzig, Bad Berka, Erfurt; large long-term acute care hospital and rehabilitation setting in Klinik Bavaria Kreischa). Screening is performed by trained study nurses. Data are collected on ICU management of sepsis. On written informed consent provided by patients or proxies, follow-up is carried out by trained research staff at 3, 6 and 12 months and yearly thereafter. The primary outcome is functional disability as assessed by (instrumental) activities of daily living. Other outcomes cover domains like mortality, cognitive, emotional and physical impairment, and resource use. The estimated sample size of 3000 ICU survivors is calculated to allow detection of relevant changes in the primary outcome in sepsis survivors longitudinally. The study is conducted according to the current version of the Declaration of Helsinki and has been approved by four local/federal responsible institutional ethics committees and by the respective federal data protection commissioners. Results of MSC will be fed back to the patients and published in peer-reviewed journals. German Clinical Trials Registry DRKS00010050. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Depression and anxiety in women with early breast cancer: five year observational cohort study

PubMed Central

Burgess, Caroline; Cornelius, Victoria; Love, Sharon; Graham, Jill; Richards, Michael; Ramirez, Amanda

2005-01-01

Objective To examine the prevalence of, and risk factors for, depression and anxiety in women with early breast cancer in the five years after diagnosis. Design Observational cohort study. Setting NHS breast clinic, London. Participants 222 women with early breast cancer: 170 (77%) provided complete interview data up to either five years after diagnosis or recurrence. Main outcome measures Prevalence of clinically important depression and anxiety (structured psychiatric interview with standardised diagnostic criteria) and clinical and patient risk factors, including stressful life experiences (Bedford College life events and difficulties schedule). Results Nearly 50% of the women with early breast cancer had depression, anxiety, or both in the year after diagnosis, 25% in the second, third, and fourth years, and 15% in the fifth year. Point prevalence was 33% at diagnosis, falling to 15% after one year. 45% of those with recurrence experienced depression, anxiety, or both within three months of the diagnosis. Previous psychological treatment predicted depression, anxiety, or both in the period around diagnosis (one month before diagnosis to four months after diagnosis). Longer term depression and anxiety, were associated with previous psychological treatment, lack of an intimate confiding relationship, younger age, and severely stressful non-cancer life experiences. Clinical factors were not associated with depression and anxiety, at any time. Lack of intimate confiding support also predicted more protracted episodes of depression and anxiety. Conclusion Increased levels of depression, anxiety, or both in the first year after a diagnosis of early breast cancer highlight the need for dedicated service provision during this time. Psychological interventions for women with breast cancer who remain disease free should take account of the broader social context in which the cancer occurs, with a focus on improving social support. PMID:15695497

EUropean prospective cohort study on Enterobacteriaceae showing REsistance to CArbapenems (EURECA): a protocol of a European multicentre observational study.

PubMed

Gutiérrez-Gutiérrez, Belén; Sojo-Dorado, Jesús; Bravo-Ferrer, José; Cuperus, Nienke; de Kraker, Marlieke; Kostyanev, Tomislav; Raka, Lul; Daikos, George; Feifel, Jan; Folgori, Laura; Pascual, Alvaro; Goossens, Herman; O'Brien, Seamus; Bonten, Marc J M; Rodríguez-Baño, Jesús

2017-04-03

The rapid worldwide spread of carbapenem-resistant Enterobacteriaceae (CRE) constitutes a major challenge. The aim of the EUropean prospective cohort study on Enterobacteriaceae showing REsistance to CArbapenems (EURECA), which is part of the Innovative Medicines Initiative Joint Undertaking (IMI JU) funded COMBACTE-CARE project, is to investigate risk factors for and outcome determinants of CRE infections to inform randomised clinical trial designs and to provide a historical cohort that could eventually be used for future comparisons with new drugs targeting CRE. A multicentre (50 sites), multinational (11 European countries), analytical observational project was designed, comprising 3 studies. The aims of study 1 (a prospective cohort study) include characterising the features, clinical management and outcomes of hospitalised patients with intra-abdominal infection, pneumonia, complicated urinary tract infections and bloodstream infections caused by CRE (202 patients in each group). The main outcomes will be 30-day all-cause mortality and clinical response. Study 2 (a nested case-control study) will identify the risk factors for target infections caused by CRE; 248 selected patients from study 1 will be matched with patients with carbapenem-susceptible Enterobacteriaceae (1:1) and with hospitalised patients (1:3) and will provide a historical cohort of patients with CRE infections. Study 3 (a matched cohort study) will follow patients in study 2 in order to assess mortality, length of stay and hospital costs associated with CRE. All patients will be followed for 30 days. Different, up-to-date statistical methods will be applied to come to unbiased estimates for all 3 studies. Before-study sites will be initiated, approval will be sought from appropriate regulatory agencies and local Ethics Committees of Research or Institutional Review Boards (IRBs) to conduct the study in accordance with regulatory requirements. This is an observational study and therefore no

Non-cancer morbidity among Estonian Chernobyl cleanup workers: a register-based cohort study

PubMed Central

Rahu, Kaja; Bromet, Evelyn J; Hakulinen, Timo; Auvinen, Anssi; Uusküla, Anneli; Rahu, Mati

2014-01-01

Objective To examine non-cancer morbidity in the Estonian Chernobyl cleanup workers cohort compared with the population sample with special attention to radiation-related diseases and mental health disorders. Design Register-based cohort study. Setting Estonia. Participants An exposed cohort of 3680 men (cleanup workers) and an unexposed cohort of 7631 men (population sample) were followed from 2004 to 2012 through the Population Registry and Health Insurance Fund database. Methods Morbidity in the exposed cohort compared with the unexposed controls was estimated in terms of rate ratio (RR) with 95% CIs using Poisson regression models. Results Elevated morbidity in the exposed cohort was found for diseases of the nervous system, digestive system, musculoskeletal system, ischaemic heart disease and for external causes. The most salient excess risk was observed for thyroid diseases (RR=1.69; 95% CI 1.38 to 2.07), intentional self-harm (RR=1.47; 95% CI 1.04 to 2.09) and selected alcohol-related diagnoses (RR=1.25; 95% CI 1.12 to 1.39). No increase in morbidity for stress reactions, depression, headaches or sleep disorders was detected. Conclusions No obvious excess morbidity consistent with biological effects of radiation was seen in the exposed cohort, with the possible exception of benign thyroid diseases. Increased alcohol-induced morbidity may reflect alcohol abuse, and could underlie some of the higher morbidity rates. Mental disorders in the exposed cohort were probably under-reported. The future challenge will be to study mental and physical comorbidities in the Chernobyl cleanup workers cohort. PMID:24833681

Assessing the Student-Instructional Setting Interface Using an Eco-Behavioral Observation System.

ERIC Educational Resources Information Center

Hendrickson, Jo M.

1992-01-01

An eco-behavioral observation system was developed for use with students with behavior disorders or emotional disturbances. Discussed are the ecosystem definition, the student-instructional setting interface, and the assessment procedure, including evaluation of the quality of academic responding, program evaluation, staff development, and…

Moving a randomized clinical trial into an observational cohort.

PubMed

Goodman, Phyllis J; Hartline, Jo Ann; Tangen, Catherine M; Crowley, John J; Minasian, Lori M; Klein, Eric A; Cook, Elise D; Darke, Amy K; Arnold, Kathryn B; Anderson, Karen; Yee, Monica; Meyskens, Frank L; Baker, Laurence H

2013-02-01

The Selenium and Vitamin E Cancer Prevention Trial (SELECT) was a randomized, double-blind, placebo-controlled prostate cancer prevention study funded by the National Cancer Institute (NCI) and conducted by the Southwest Oncology Group (SWOG). A total of 35,533 men were assigned randomly to one of the four treatment groups (vitamin E + placebo, selenium + placebo, vitamin E + selenium, and placebo + placebo). The independent Data and Safety Monitoring Committee (DSMC) recommended the discontinuation of study supplements because of the lack of efficacy for risk reduction and because futility analyses demonstrated no possibility of benefit of the supplements to the anticipated degree (25% reduction in prostate cancer incidence) with additional follow-up. Study leadership agreed that the randomized trial should be terminated but believed that the cohort should be maintained and followed as the additional follow-up would contribute important information to the understanding of the biologic consequences of the intervention. Since the participants no longer needed to be seen in person to assess acute toxicities or to be given study supplements, it was determined that the most efficient and cost-effective way to follow them was via a central coordinated effort. A number of changes were necessary at the local Study Sites and SELECT Statistical Center to transition to following participants via a Central Coordinating Center. We describe the transition process from a randomized clinical trial to the observational Centralized Follow-Up (CFU) study. The process of transitioning SELECT, implemented at more than 400 Study Sites across the United States, Canada, and Puerto Rico, entailed many critical decisions and actions including updates to online documents such as the SELECT Workbench and Study Manual, a protocol amendment, reorganization of the Statistical Center, creation of a Transition Committee, development of materials for SELECT Study Sites, development of procedures

Moving a Randomized Clinical Trial into an Observational Cohort

PubMed Central

Goodman, Phyllis J.; Hartline, Jo Ann; Tangen, Catherine M.; Crowley, John J.; Minasian, Lori M.; Klein, Eric A.; Cook, Elise D.; Darke, Amy K.; Arnold, Kathryn B.; Anderson, Karen; Yee, Monica; Meyskens, Frank L.; Baker, Laurence H.

2013-01-01

Background The Selenium and Vitamin E Cancer Prevention Trial (SELECT) was a randomized, double blind, placebo-controlled prostate cancer prevention study funded by the National Cancer Institute and conducted by SWOG (Southwest Oncology Group). A total of 35,533 men were assigned randomly to one of four treatment groups (vitamin E + placebo, selenium + placebo, vitamin E + selenium, placebo + placebo. The independent Data and Safety Monitoring Committee recommended the discontinuation of study supplements because of the lack of efficacy for risk reduction and because futility analyses demonstrated no possibility of benefit of the supplements to the anticipated degree (25% reduction in prostate cancer incidence) with additional follow-up. Study leadership agreed that the randomized trial should be terminated but believed that the cohort should be maintained and followed as the additional follow-up would contribute important information to the understanding of the biologic consequences of the intervention. Since the participants no longer needed to be seen in person to assess acute toxicities or to be given study supplements, it was determined that the most efficient and cost-effective way to follow them was via a central coordinated effort. Purpose A number of changes were necessary at the local Study Sites and SELECT Statistical Center to transition to following participants via a Central Coordinating Center. We describe the transition process from a randomized clinical trial to the observational Centralized Follow-up (CFU) study. Methods The process of transitioning SELECT, implemented at more than 400 Study Sites across the United States, Canada and Puerto Rico, entailed many critical decisions and actions including updates to online documents such as the SELECT Workbench and Study Manual, a protocol amendment, reorganization of the Statistical Center, creation of a Transition Committee, development of materials for SELECT Study Sites, development of procedures

Characteristics of the musculoskeletal symptoms observed among survivors of Ebola virus disease in the Postebogui cohort in Guinea.

PubMed

Pers, Yves-Marie; Sow, Mamadou Saliou; Taverne, Bernard; March, Laura; Izard, Suzanne; Étard, Jean François; Barry, Moumié; Touré, Abdoulaye; Delaporte, Eric

2017-12-01

Previous studies show that arthralgia is the most common symptom experienced by Ebola virus disease (EVD) survivors. Nevertheless, specific analyses of rheumatological sequelea are still lacking. The Postebogui study is a prospective, multicentre cohort aiming to evaluate the long-term outcomes of EVD survivors infected during the 2014-15 outbreak in Guinea. Of the 216 participants enrolled in the study in October 2015, 44 patients with arthralgia/myalgia underwent a physical examination by a rheumatologist (the Eborheum cohort). Data were collected using a standardized questionnaire. In the Eborheum cohort, 61% of patients were female, the median age was 31.1 years, and the median time from Ebola Treatment Centre discharge was 8.8 months. Pain manifestation started after Ebola infection in all but one patient. Patients had mainly both mechanical and inflammatory pain (45%) and low back pain (77%). All patients reported pain in at least one peripheral joint. Pain in large joints was more frequently reported than in small joints (73 vs 41%). Oligo- and polyarticular presentations were similar, with symmetrical pain distribution. Furthermore, 36 patients had at least one painful 18-tender point count, most of whom reported extensive pain (n = 19) and symmetrical distribution (91%). Diagnoses were mainly non-specific musculoskeletal disorders (59%) and mechanical back pain (52%). No polyarthritis was observed. We found a higher percentage of depressed patients compared with the remaining Postebogui group (42 vs 11%; P < 0.001). Results from the study come from the first complete rheumatological examination of a cohort of EVD survivors, nearly 9 months after Ebola Treatment Centre discharge. Importantly, we found that patients with arthralgia/myalgia included in the Eborheum cohort were more likely to experience depression than survivors not reporting these symptoms, highlighting the impact of pain symptoms among survivors. © The Author 2017. Published by Oxford

Pregnancy outcome after first trimester use of angiotensin AT1 receptor blockers: an observational cohort study.

PubMed

Hoeltzenbein, Maria; Tissen-Diabaté, Tatjana; Fietz, Anne-Katrin; Zinke, Sandra; Kayser, Angela; Meister, Reinhard; Weber-Schoendorfer, Corinna; Schaefer, Christof

2018-03-24

Ongoing discussion about the safety of renin-angiotensin inhibitors in the first trimester and limited data on pregnancy outcomes after exposure to angiotensin AT1 receptor blockers (ARBs). Observational cohort study compares outcomes of 215 prospectively ascertained pregnancies with first trimester exposure to ARBs with 642 non-hypertensive pregnancies. The rate of major birth defects in the ARB cohort (9/168, 5.4%) was higher than in the comparison group (17/570, 3%), but not significantly increased (OR adj 1.9, 95% CI 0.7-4.9). There was no distinct pattern of anomalies among infants with birth defects. The risk of spontaneous abortions was not increased (HR adj 0.9, 95% CI 0.5-1.6), although the cumulative incidence was in the upper normal range (0.22, 95% CI 0.15-0.32). Higher rates of prematurity (OR adj 3.0; 95% CI 1.7-5.1) and a reduced birth weight after adjustment for sex and gestational age were observed. There was no evidence for an increased risk for major birth defects, spontaneous abortions, or preterm birth in a sensitivity analysis comparing ARB exposed hypertensive women to hypertensive women without ARB exposure during the first trimester. Our study supports the hypothesis that ARBs are not major teratogens. Patients inadvertently exposed to ARBs during the early pregnancy may be reassured. Nevertheless, women planning pregnancy should avoid ARBs. In selected cases, ARBs might be continued under careful monitoring of menstrual cycle and discontinued as soon as pregnancy is recognized.

Classical homeopathy in the treatment of cancer patients--a prospective observational study of two independent cohorts.

PubMed

Rostock, Matthias; Naumann, Johannes; Guethlin, Corina; Guenther, Lars; Bartsch, Hans H; Walach, Harald

2011-01-17

Many cancer patients seek homeopathy as a complementary therapy. It has rarely been studied systematically, whether homeopathic care is of benefit for cancer patients. We conducted a prospective observational study with cancer patients in two differently treated cohorts: one cohort with patients under complementary homeopathic treatment (HG; n = 259), and one cohort with conventionally treated cancer patients (CG; n = 380). For a direct comparison, matched pairs with patients of the same tumour entity and comparable prognosis were to be formed. Main outcome parameter: change of quality of life (FACT-G, FACIT-Sp) after 3 months. Secondary outcome parameters: change of quality of life (FACT-G, FACIT-Sp) after a year, as well as impairment by fatigue (MFI) and by anxiety and depression (HADS). HG: FACT-G, or FACIT-Sp, respectively improved statistically significantly in the first three months, from 75.6 (SD 14.6) to 81.1 (SD 16.9), or from 32.1 (SD 8.2) to 34.9 (SD 8.32), respectively. After 12 months, a further increase to 84.1 (SD 15.5) or 35.2 (SD 8.6) was found. Fatigue (MFI) decreased; anxiety and depression (HADS) did not change. CG: FACT-G remained constant in the first three months: 75.3 (SD 17.3) at t0, and 76.6 (SD 16.6) at t1. After 12 months, there was a slight increase to 78.9 (SD 18.1). FACIT-Sp scores improved significantly from t0 (31.0 - SD 8.9) to t1 (32.1 - SD 8.9) and declined again after a year (31.6 - SD 9.4). For fatigue, anxiety, and depression, no relevant changes were found. 120 patients of HG and 206 patients of CG met our criteria for matched-pairs selection. Due to large differences between the two patient populations, however, only 11 matched pairs could be formed. This is not sufficient for a comparative study. In our prospective study, we observed an improvement of quality of life as well as a tendency of fatigue symptoms to decrease in cancer patients under complementary homeopathic treatment. It would take considerably larger samples

Japanese Legacy Cohorts: The Life Span Study Atomic Bomb Survivor Cohort and Survivors’ Offspring

PubMed Central

Grant, Eric J; Kodama, Kazunori

2018-01-01

Cohorts of atomic bomb survivors—including those exposed in utero—and children conceived after parental exposure were established to investigate late health effects of atomic bomb radiation and its transgenerational effects by the Atomic Bomb Casualty Commission (ABCC) in the 1950s. ABCC was reorganized to the Radiation Effects Research Foundation (RERF) in 1975, and all work has been continued at RERF. The Life Span Study, the cohort of survivors, consists of about 120,000 subjects and has been followed since 1950. Cohorts of in utero survivors and the survivors’ children include about 3,600 and 77,000 subjects, respectively, and have been followed since 1945. Atomic bomb radiation dose was estimated for each subject based on location at the time of the bombing and shielding conditions from exposure, which were obtained through enormous efforts of investigators and cooperation of subjects. Outcomes include vital status, cause of death, and cancer incidence. In addition, sub-cohorts of these three cohorts were constructed to examine clinical features of late health effects, and the subjects have been invited to periodic health examinations at clinics of ABCC and RERF. They were also asked to donate biosamples for biomedical investigations. Epidemiological studies have observed increased radiation risks for malignant diseases among survivors, including those exposed in utero, and possible risks for some non-cancer diseases. In children of survivors, no increased risks due to parental exposure to radiation have been observed for malignancies or other diseases, but investigations are continuing, as these cohorts are still relatively young. PMID:29553058

Japanese Legacy Cohorts: The Life Span Study Atomic Bomb Survivor Cohort and Survivors' Offspring.

PubMed

Ozasa, Kotaro; Grant, Eric J; Kodama, Kazunori

2018-04-05

Cohorts of atomic bomb survivors-including those exposed in utero-and children conceived after parental exposure were established to investigate late health effects of atomic bomb radiation and its transgenerational effects by the Atomic Bomb Casualty Commission (ABCC) in the 1950s. ABCC was reorganized to the Radiation Effects Research Foundation (RERF) in 1975, and all work has been continued at RERF. The Life Span Study, the cohort of survivors, consists of about 120,000 subjects and has been followed since 1950. Cohorts of in utero survivors and the survivors' children include about 3,600 and 77,000 subjects, respectively, and have been followed since 1945. Atomic bomb radiation dose was estimated for each subject based on location at the time of the bombing and shielding conditions from exposure, which were obtained through enormous efforts of investigators and cooperation of subjects. Outcomes include vital status, cause of death, and cancer incidence. In addition, sub-cohorts of these three cohorts were constructed to examine clinical features of late health effects, and the subjects have been invited to periodic health examinations at clinics of ABCC and RERF. They were also asked to donate biosamples for biomedical investigations. Epidemiological studies have observed increased radiation risks for malignant diseases among survivors, including those exposed in utero, and possible risks for some non-cancer diseases. In children of survivors, no increased risks due to parental exposure to radiation have been observed for malignancies or other diseases, but investigations are continuing, as these cohorts are still relatively young.

Feasibility of a cohort study on health risks caused by occupational exposure to radiofrequency electromagnetic fields

PubMed Central

2009-01-01

Background The aim of this study was to examine the feasibility of performing a cohort study on health risks from occupational exposure to radiofrequency electromagnetic fields (RF-EMF) in Germany. Methods A set of criteria was developed to evaluate the feasibility of such a cohort study. The criteria aimed at conditions of exposure and exposure assessment (level, duration, preferably on an individual basis), the possibility to assemble a cohort and the feasibility of ascertaining various disease endpoints. Results Twenty occupational settings with workers potentially exposed to RF-EMF and, in addition, a cohort of amateur radio operators were considered. Based on expert ratings, literature reviews and our set of predefined criteria, three of the cohorts were identified as promising for further evaluation: the personnel (technicians) of medium/short wave broadcasting stations, amateur radio operators, and workers on dielectric heat sealers. After further analyses, the cohort of workers on dielectric heat sealers seems not to be feasible due to the small number of exposed workers available and to the difficulty of assessing exposure (exposure depends heavily on the respective working process and mixture of exposures, e.g. plastic vapours), although exposure was highest in this occupational setting. The advantage of the cohort of amateur radio operators was the large number of persons it includes, while the advantage of the cohort of personnel working at broadcasting stations was the quality of retrospective exposure assessment. However, in the cohort of amateur radio operators the exposure assessment was limited, and the cohort of technicians was hampered by the small number of persons working in this profession. Conclusion The majority of occupational groups exposed to RF-EMF are not practicable for setting up an occupational cohort study due to the small numbers of exposed subjects or due to exposure levels being only marginally higher than those of the general

Using climate models to estimate the quality of global observational data sets.

PubMed

Massonnet, François; Bellprat, Omar; Guemas, Virginie; Doblas-Reyes, Francisco J

2016-10-28

Observational estimates of the climate system are essential to monitoring and understanding ongoing climate change and to assessing the quality of climate models used to produce near- and long-term climate information. This study poses the dual and unconventional question: Can climate models be used to assess the quality of observational references? We show that this question not only rests on solid theoretical grounds but also offers insightful applications in practice. By comparing four observational products of sea surface temperature with a large multimodel climate forecast ensemble, we find compelling evidence that models systematically score better against the most recent, advanced, but also most independent product. These results call for generalized procedures of model-observation comparison and provide guidance for a more objective observational data set selection. Copyright © 2016, American Association for the Advancement of Science.

A comparison of entropy balance and probability weighting methods to generalize observational cohorts to a population: a simulation and empirical example.

PubMed

Harvey, Raymond A; Hayden, Jennifer D; Kamble, Pravin S; Bouchard, Jonathan R; Huang, Joanna C

2017-04-01

We compared methods to control bias and confounding in observational studies including inverse probability weighting (IPW) and stabilized IPW (sIPW). These methods often require iteration and post-calibration to achieve covariate balance. In comparison, entropy balance (EB) optimizes covariate balance a priori by calibrating weights using the target's moments as constraints. We measured covariate balance empirically and by simulation by using absolute standardized mean difference (ASMD), absolute bias (AB), and root mean square error (RMSE), investigating two scenarios: the size of the observed (exposed) cohort exceeds the target (unexposed) cohort and vice versa. The empirical application weighted a commercial health plan cohort to a nationally representative National Health and Nutrition Examination Survey target on the same covariates and compared average total health care cost estimates across methods. Entropy balance alone achieved balance (ASMD ≤ 0.10) on all covariates in simulation and empirically. In simulation scenario I, EB achieved the lowest AB and RMSE (13.64, 31.19) compared with IPW (263.05, 263.99) and sIPW (319.91, 320.71). In scenario II, EB outperformed IPW and sIPW with smaller AB and RMSE. In scenarios I and II, EB achieved the lowest mean estimate difference from the simulated population outcome ($490.05, $487.62) compared with IPW and sIPW, respectively. Empirically, only EB differed from the unweighted mean cost indicating IPW, and sIPW weighting was ineffective. Entropy balance demonstrated the bias-variance tradeoff achieving higher estimate accuracy, yet lower estimate precision, compared with IPW methods. EB weighting required no post-processing and effectively mitigated observed bias and confounding. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Safety and efficacy of hysteroscopic sterilization compared with laparoscopic sterilization: an observational cohort study.

PubMed

Mao, Jialin; Pfeifer, Samantha; Schlegel, Peter; Sedrakyan, Art

2015-10-13

To compare the safety and efficacy of hysteroscopic sterilization with the "Essure" device with laparoscopic sterilization in a large, all-inclusive, state cohort. Population based cohort study. Outpatient interventional setting in New York State. Women undergoing interval sterilization procedure, including hysteroscopic sterilization with Essure device and laparoscopic surgery, between 2005 and 2013. Safety events within 30 days of procedures; unintended pregnancies and reoperations within one year of procedures. Mixed model accounting for hospital clustering was used to compare 30 day and 1 year outcomes, adjusting for patient characteristics and other confounders. Time to reoperation was evaluated using frailty model for time to event analysis. We identified 8048 patients undergoing hysteroscopic sterilization and 44,278 undergoing laparoscopic sterilization between 2005 and 2013 in New York State. There was a significant increase in the use of hysteroscopic procedures during this period, while use of laparoscopic sterilization decreased. Patients undergoing hysteroscopic sterilization were older than those undergoing laparoscopic sterilization and were more likely to have a history of pelvic inflammatory disease (10.3% v 7.2%, P<0.01), major abdominal surgery (9.4% v 7.9%, P<0.01), and cesarean section (23.2% v 15.4%, P<0.01). At one year after surgery, hysteroscopic sterilization was not associated with a higher risk of unintended pregnancy (odds ratio 0.84 (95% CI 0.63 to 1.12)) but was associated with a substantially increased risk of reoperation (odds ratio 10.16 (7.47 to 13.81)) compared with laparoscopic sterilization. Patients undergoing hysteroscopic sterilization have a similar risk of unintended pregnancy but a more than 10-fold higher risk of undergoing reoperation compared with patients undergoing laparoscopic sterilization. Benefits and risks of both procedures should be discussed with patients for informed decisions making. © Mao et al 2015.

Feasibility of an Immersive Virtual Reality Intervention for Hospitalized Patients: An Observational Cohort Study

PubMed Central

2016-01-01

Background Virtual reality (VR) offers immersive, realistic, three-dimensional experiences that “transport” users to novel environments. Because VR is effective for acute pain and anxiety, it may have benefits for hospitalized patients; however, there are few reports using VR in this setting. Objective The aim was to evaluate the acceptability and feasibility of VR in a diverse cohort of hospitalized patients. Methods We assessed the acceptability and feasibility of VR in a cohort of patients admitted to an inpatient hospitalist service over a 4-month period. We excluded patients with motion sickness, stroke, seizure, dementia, nausea, and in isolation. Eligible patients viewed VR experiences (eg, ocean exploration; Cirque du Soleil; tour of Iceland) with Samsung Gear VR goggles. We then conducted semistructured patient interview and performed statistical testing to compare patients willing versus unwilling to use VR. Results We evaluated 510 patients; 423 were excluded and 57 refused to participate, leaving 30 participants. Patients willing versus unwilling to use VR were younger (mean 49.1, SD 17.4 years vs mean 60.2, SD 17.7 years; P=.01); there were no differences by sex, race, or ethnicity. Among users, most reported a positive experience and indicated that VR could improve pain and anxiety, although many felt the goggles were uncomfortable. Conclusions Most inpatient users of VR described the experience as pleasant and capable of reducing pain and anxiety. However, few hospitalized patients in this “real-world” series were both eligible and willing to use VR. Consistent with the “digital divide” for emerging technologies, younger patients were more willing to participate. Future research should evaluate the impact of VR on clinical and resource outcomes. ClinicalTrial Clinicaltrials.gov NCT02456987; https://clinicaltrials.gov/ct2/show/NCT02456987 (Archived by WebCite at http://www.webcitation.org/6iFIMRNh3) PMID:27349654

Feasibility of an Immersive Virtual Reality Intervention for Hospitalized Patients: An Observational Cohort Study.

PubMed

Mosadeghi, Sasan; Reid, Mark William; Martinez, Bibiana; Rosen, Bradley Todd; Spiegel, Brennan Mason Ross

2016-06-27

Virtual reality (VR) offers immersive, realistic, three-dimensional experiences that "transport" users to novel environments. Because VR is effective for acute pain and anxiety, it may have benefits for hospitalized patients; however, there are few reports using VR in this setting. The aim was to evaluate the acceptability and feasibility of VR in a diverse cohort of hospitalized patients. We assessed the acceptability and feasibility of VR in a cohort of patients admitted to an inpatient hospitalist service over a 4-month period. We excluded patients with motion sickness, stroke, seizure, dementia, nausea, and in isolation. Eligible patients viewed VR experiences (eg, ocean exploration; Cirque du Soleil; tour of Iceland) with Samsung Gear VR goggles. We then conducted semistructured patient interview and performed statistical testing to compare patients willing versus unwilling to use VR. We evaluated 510 patients; 423 were excluded and 57 refused to participate, leaving 30 participants. Patients willing versus unwilling to use VR were younger (mean 49.1, SD 17.4 years vs mean 60.2, SD 17.7 years; P=.01); there were no differences by sex, race, or ethnicity. Among users, most reported a positive experience and indicated that VR could improve pain and anxiety, although many felt the goggles were uncomfortable. Most inpatient users of VR described the experience as pleasant and capable of reducing pain and anxiety. However, few hospitalized patients in this "real-world" series were both eligible and willing to use VR. Consistent with the "digital divide" for emerging technologies, younger patients were more willing to participate. Future research should evaluate the impact of VR on clinical and resource outcomes. Clinicaltrials.gov NCT02456987; https://clinicaltrials.gov/ct2/show/NCT02456987 (Archived by WebCite at http://www.webcitation.org/6iFIMRNh3).

Observations of Children's Interactions with Teachers, Peers, and Tasks across Preschool Classroom Activity Settings

ERIC Educational Resources Information Center

Booren, Leslie M.; Downer, Jason T.; Vitiello, Virginia E.

2012-01-01

Research Findings: This descriptive study examined classroom activity settings in relation to children's observed behavior during classroom interactions, child gender, and basic teacher behavior within the preschool classroom. A total of 145 children were observed for an average of 80 min during 8 occasions across 2 days using the Individualized…

The pediatric resuscitative thoracotomy during combat operations in Iraq and Afghanistan - A retrospective cohort study.

PubMed

Schauer, Steven G; Hill, Guyon J; Connor, Richard E; Oh, John S; April, Michael D

2018-05-01

Combat zone trauma poses a unique set of challenges and injury patterns not seen in the civilian setting. The role of the pediatric resuscitative thoracotomy in combat zones remains unclear given a paucity of data regarding procedure outcomes in this setting. We compare outcomes among children in traumatic arrest undergoing resuscitative thoracotomy versus cardiopulmonary (CPR) resuscitation only. We queried the Department of Defense Trauma Registry (DODTR) from 2007 to 2016 for all pediatric subjects that underwent a resuscitative thoracotomy or CPR in the prehospital or emergency department setting during operations in Iraq or Afghanistan. We removed CPR subjects with mechanisms of injury not matched in the thoracotomy cohort. During the study period, there were 3439 pediatric encounters. We identified 13 subjects who underwent a resuscitative thoracotomy and 66 subjects who underwent CPR without thoracotomy with matching mechanisms of injury. When comparing the two cohorts those in the thoracotomy group had higher median thorax body region scores (median 3 versus 0, p = .001), but a trend towards higher rates of survival to discharge (31% versus 9%, p = .108). The youngest survivor in the thoracotomy cohort was less than 1 year old. We observed a trend towards higher survival among subjects that underwent a resuscitative thoracotomy survived to hospital discharge compared to subjects undergoing CPR without thoracotomy. The literature will benefit from further data to confirm an association between this procedure and a survival benefit among pediatric subjects in the resource limited setting. Furthermore, improvements in documentation will guide equipping and training providers expected to care for pediatric trauma patients. Published by Elsevier Ltd.

MP estimation applied to platykurtic sets of geodetic observations

NASA Astrophysics Data System (ADS)

Wiśniewski, Zbigniew

2017-06-01

MP estimation is a method which concerns estimating of the location parameters when the probabilistic models of observations differ from the normal distributions in the kurtosis or asymmetry. The system of Pearson's distributions is the probabilistic basis for the method. So far, such a method was applied and analyzed mostly for leptokurtic or mesokurtic distributions (Pearson's distributions of types IV or VII), which predominate practical cases. The analyses of geodetic or astronomical observations show that we may also deal with sets which have moderate asymmetry or small negative excess kurtosis. Asymmetry might result from the influence of many small systematic errors, which were not eliminated during preprocessing of data. The excess kurtosis can be related with bigger or smaller (in relations to the Hagen hypothesis) frequency of occurrence of the elementary errors which are close to zero. Considering that fact, this paper focuses on the estimation with application of the Pearson platykurtic distributions of types I or II. The paper presents the solution of the corresponding optimization problem and its basic properties. Although platykurtic distributions are rare in practice, it was an interesting issue to find out what results can be provided by MP estimation in the case of such observation distributions. The numerical tests which are presented in the paper are rather limited; however, they allow us to draw some general conclusions.

Comparing the cohort design and the nested case–control design in the presence of both time-invariant and time-dependent treatment and competing risks: bias and precision

PubMed Central

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

Survival after postoperative morbidity: a longitudinal observational cohort study.

PubMed

Moonesinghe, S R; Harris, S; Mythen, M G; Rowan, K M; Haddad, F S; Emberton, M; Grocott, M P W

2014-12-01

Previous studies have suggested that there may be long-term harm associated with postoperative complications. Uncertainty exists however, because of the need for risk adjustment and inconsistent definitions of postoperative morbidity. We did a longitudinal observational cohort study of patients undergoing major surgery. Case-mix adjustment was applied and morbidity was recorded using a validated outcome measure. Cox proportional hazards modelling using time-dependent covariates was used to measure the independent relationship between prolonged postoperative morbidity and longer term survival. Data were analysed for 1362 patients. The median length of stay was 9 days and the median follow-up time was 6.5 yr. Independent of perioperative risk, postoperative neurological morbidity (prevalence 2.9%) was associated with a relative hazard for long-term mortality of 2.00 [P=0.001; 95% confidence interval (CI) 1.32-3.04]. Prolonged postoperative morbidity (prevalence 15.6%) conferred a relative hazard for death in the first 12 months after surgery of 3.51 (P<0.001; 95% CI 2.28-5.42) and for the next 2 yr of 2.44 (P<0.001; 95% CI 1.62-3.65), returning to baseline thereafter. Prolonged morbidity after surgery is associated with a risk of premature death for a longer duration than perhaps is commonly thought; however, this risk falls with time. We suggest that prolonged postoperative morbidity measured in this way may be a valid indicator of the quality of surgical healthcare. Our findings reinforce the importance of research and quality improvement initiatives aimed at reducing the duration and severity of postoperative complications. © The Author 2014. Published by Oxford University Press on behalf of the British Journal of Anaesthesia.

CONSTANCES: a general prospective population-based cohort for occupational and environmental epidemiology: cohort profile.

PubMed

Goldberg, Marcel; Carton, Matthieu; Descatha, Alexis; Leclerc, Annette; Roquelaure, Yves; Santin, Gaëlle; Zins, Marie

2017-01-01

WHY THE COHORT WAS SET UP?: CONSTANCES is a general-purpose cohort with a focus on occupational and environmental factors. CONSTANCES was designed as a randomly selected sample of French adults aged 18-69 years at inception; 200 000 participants will be included. At enrolment, the participants are invited to complete questionnaires and to attend a health screening centre (HSC) for a health examination. A biobank will be set up. The follow-up includes an yearly self-administered questionnaire, a periodic visit to an HSC and linkage to social and national health administrative databases. Data collected for participants include social and demographic characteristics, socioeconomic status, life events and behaviours. Regarding occupational and environmental factors, a wealth of data on organisational, chemical, biological, biomechanical and psychosocial lifelong exposure, as well as residential characteristics, are collected at enrolment and during follow-up. The health data cover a wide spectrum: self-reported health scales, reported prevalent and incident diseases, long-term chronic diseases and hospitalisations, sick-leaves, handicaps, limitations, disabilities and injuries, healthcare usage and services provided, and causes of death. To take into account non-participation and attrition, a random cohort of non-participants was set up and will be followed through the same national databases as participants. Inclusions begun at the end of 2012 and more than 110 000 participants were already included by September 2016. Several projects on occupational and environmental risks already applied to a public call for nested research projects. 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/.

Prospective observational cohort studies for studying rare diseases: the European PedNet Haemophilia Registry.

PubMed

Fischer, K; Ljung, R; Platokouki, H; Liesner, R; Claeyssens, S; Smink, E; van den Berg, H M

2014-07-01

Haemophilia is a rare disease. To improve knowledge, prospective studies of large numbers of subjects are needed. To establish a large well-documented birth cohort of patients with haemophilia enabling studies on early presentation, side effects and outcome of treatment. Twenty-one haemophilia treatment centres have been collecting data on all children with haemophilia with FVIII/IX levels up to 25% born from 2000 onwards. Another eight centres collected data on severe haemophilia A only. At baseline, details on delivery and diagnosis, gene mutation, family history of haemophilia and inhibitors are collected. For the first 75 exposure days, date, reason, dose and product are recorded for each infusion. Clinically relevant inhibitors are defined as follows: at least two positive inhibitor titres and a FVIII/IX recovery <66% of expected. For inhibitor patients, results of all inhibitor- and recovery tests are collected. For continued treatment, data on bleeding, surgery, prophylaxis and clotting factor consumption are collected annually. Data are downloaded for analysis annually. In May 2013, a total of 1094 patients were included: 701 with severe, 146 with moderate and 247 with mild haemophilia. Gene defect data were available for 87.6% of patients with severe haemophilia A. The first analysis, performed in May 2011, lead to two landmark publications. The outcome of this large collaborative research confirms its value for the improvement of haemophilia care. High-quality prospective observational cohorts form an ideal source to study natural history and treatment in rare diseases such as haemophilia. © 2014 John Wiley & Sons Ltd.

Changes in cohort wealth over a generation.

PubMed

David, M H; Menchik, P L

1988-08-01

Empirical computation of expected wealth is hampered by two problems: mortality risks vary in the population and over time; and observation of net estates for most cohorts is truncated, as some individuals in a cohort survive the calendar date on which observation is terminated. These two problems are solved in estimating cohort wealth for a sample of Wisconsin taxpayers. Hazard rate models of differential occupational mortality risks were estimated from the occupational information on the tax records. Values of net estate are simulated for individuals in each birth cohort who survived. Survivors have characteristics that imply greater wealth holdings than the deceased in every birth year covered by the study (1890-1924). Because of this, estimates of wealth-age relationships produced by the estate multiplier method for any given year will have a serious downward bias. Longitudinal data imply that dissaving does not occur after age 65.

Dynamic models for estimating the effect of HAART on CD4 in observational studies: Application to the Aquitaine Cohort and the Swiss HIV Cohort Study.

PubMed

Prague, Mélanie; Commenges, Daniel; Gran, Jon Michael; Ledergerber, Bruno; Young, Jim; Furrer, Hansjakob; Thiébaut, Rodolphe

2017-03-01

Highly active antiretroviral therapy (HAART) has proved efficient in increasing CD4 counts in many randomized clinical trials. Because randomized trials have some limitations (e.g., short duration, highly selected subjects), it is interesting to assess the effect of treatments using observational studies. This is challenging because treatment is started preferentially in subjects with severe conditions. This general problem had been treated using Marginal Structural Models (MSM) relying on the counterfactual formulation. Another approach to causality is based on dynamical models. We present three discrete-time dynamic models based on linear increments models (LIM): the first one based on one difference equation for CD4 counts, the second with an equilibrium point, and the third based on a system of two difference equations, which allows jointly modeling CD4 counts and viral load. We also consider continuous-time models based on ordinary differential equations with non-linear mixed effects (ODE-NLME). These mechanistic models allow incorporating biological knowledge when available, which leads to increased statistical evidence for detecting treatment effect. Because inference in ODE-NLME is numerically challenging and requires specific methods and softwares, LIM are a valuable intermediary option in terms of consistency, precision, and complexity. We compare the different approaches in simulation and in illustration on the ANRS CO3 Aquitaine Cohort and the Swiss HIV Cohort Study. © 2016, The International Biometric Society.

Global long-term ozone trends derived from different observed and modelled data sets

NASA Astrophysics Data System (ADS)

Coldewey-Egbers, M.; Loyola, D.; Zimmer, W.; van Roozendael, M.; Lerot, C.; Dameris, M.; Garny, H.; Braesicke, P.; Koukouli, M.; Balis, D.

2012-04-01

The long-term behaviour of stratospheric ozone amounts during the past three decades is investigated on a global scale using different observed and modelled data sets. Three European satellite sensors GOME/ERS-2, SCIAMACHY/ENVISAT, and GOME-2/METOP are combined and a merged global monthly mean total ozone product has been prepared using an inter-satellite calibration approach. The data set covers the 16-years period from June 1995 to June 2011 and it exhibits an excellent long-term stability, which is required for such trend studies. A multiple linear least-squares regression algorithm using different explanatory variables is applied to the time series and statistically significant positive trends are detected in the northern mid latitudes and subtropics. Global trends are also estimated using a second satellite-based Merged Ozone Data set (MOD) provided by NASA. For few selected geographical regions ozone trends are additionally calculated using well-maintained measurements of individual Dobson/Brewer ground-based instruments. A reasonable agreement in the spatial patterns of the trends is found amongst the European satellite, the NASA satellite, and the ground-based observations. Furthermore, two long-term simulations obtained with the Chemistry-Climate Models E39C-A provided by German Aerospace Center and UMUKCA-UCAM provided by University of Cambridge are analysed.

Systematic Observation of Early Adolescents in Educational Settings: The Good, the Bad, and the Ugly

ERIC Educational Resources Information Center

Gregory, Anne; Mikami, Amori Yee

2015-01-01

The growing use of systematic, empirically tested observational frameworks in school-based research is crucial for increasing the replicability and generalizability of findings across settings. That said, observations are often mistakenly assumed to be the "gold standard" assessment, without more nuanced discussions about the best uses…

Methodology Series Module 1: Cohort Studies

PubMed Central

Setia, Maninder Singh

2016-01-01

Cohort design is a type of nonexperimental or observational study design. In a cohort study, the participants do not have the outcome of interest to begin with. They are selected based on the exposure status of the individual. They are then followed over time to evaluate for the occurrence of the outcome of interest. Some examples of cohort studies are (1) Framingham Cohort study, (2) Swiss HIV Cohort study, and (3) The Danish Cohort study of psoriasis and depression. These studies may be prospective, retrospective, or a combination of both of these types. Since at the time of entry into the cohort study, the individuals do not have outcome, the temporality between exposure and outcome is well defined in a cohort design. If the exposure is rare, then a cohort design is an efficient method to study the relation between exposure and outcomes. A retrospective cohort study can be completed fast and is relatively inexpensive compared with a prospective cohort study. Follow-up of the study participants is very important in a cohort study, and losses are an important source of bias in these types of studies. These studies are used to estimate the cumulative incidence and incidence rate. One of the main strengths of a cohort study is the longitudinal nature of the data. Some of the variables in the data will be time-varying and some may be time independent. Thus, advanced modeling techniques (such as fixed and random effects models) are useful in analysis of these studies. PMID:26955090

Methodology Series Module 1: Cohort Studies.

PubMed

Setia, Maninder Singh

2016-01-01

Cohort design is a type of nonexperimental or observational study design. In a cohort study, the participants do not have the outcome of interest to begin with. They are selected based on the exposure status of the individual. They are then followed over time to evaluate for the occurrence of the outcome of interest. Some examples of cohort studies are (1) Framingham Cohort study, (2) Swiss HIV Cohort study, and (3) The Danish Cohort study of psoriasis and depression. These studies may be prospective, retrospective, or a combination of both of these types. Since at the time of entry into the cohort study, the individuals do not have outcome, the temporality between exposure and outcome is well defined in a cohort design. If the exposure is rare, then a cohort design is an efficient method to study the relation between exposure and outcomes. A retrospective cohort study can be completed fast and is relatively inexpensive compared with a prospective cohort study. Follow-up of the study participants is very important in a cohort study, and losses are an important source of bias in these types of studies. These studies are used to estimate the cumulative incidence and incidence rate. One of the main strengths of a cohort study is the longitudinal nature of the data. Some of the variables in the data will be time-varying and some may be time independent. Thus, advanced modeling techniques (such as fixed and random effects models) are useful in analysis of these studies.

Effectiveness and Persistence of Liraglutide Treatment Among Patients with Type 2 Diabetes Treated in Primary Care and Specialist Settings: A Subgroup Analysis from the EVIDENCE Study, a Prospective, 2-Year Follow-up, Observational, Post-Marketing Study.

PubMed

Martinez, Luc; Penfornis, Alfred; Gautier, Jean-Francois; Eschwège, Eveline; Charpentier, Guillaume; Bouzidi, Amira; Gourdy, Pierre

2017-03-01

The objective of this subgroup analysis is to investigate the effectiveness of liraglutide in people with type 2 diabetes (T2D) treated within the primary care physician (PCP) and specialist care settings. EVIDENCE is a prospective, observational study of 3152 adults with T2D recently starting or about to start liraglutide treatment in France. We followed patients in the PCP and specialist settings for 2 years to evaluate the effectiveness of liraglutide in glycemic control and body weight reduction. Furthermore, we evaluated the changes in combined antihyperglycemic treatments, the reasons for prescribing liraglutide, patient satisfaction, and safety of liraglutide in these two treatment settings. After 2 years of follow-up, 477 out of 1209 (39.0%) of PCP and 297 out of 1398 (21.2%) of specialist-treated patients still used liraglutide and maintained the glycated hemoglobin (HbA 1c ) target of <7.0%. Significant reductions from baseline were observed in both PCP- and specialist-treated cohorts in mean HbA 1c (-1.22% and -0.8%, respectively), fasting plasma glucose (FPG) concentration (-39 and -23 mg/dL), body weight (-4.4 and -3.8 kg), and body mass index (BMI) (-1.5 and -1.4 kg/m 2 ), all p < 0.0001. Reductions in HbA 1c and FPG were significantly greater among PCP- compared with specialist-treated patients, p < 0.0001 for both. Patient treatment satisfaction was also significantly increased in both cohorts. Reported gastrointestinal adverse events were less frequent among PCP-treated patients compared with specialist-treated patients (4.5% vs. 16.1%). Despite differences in demography and clinical characteristics of patients treated for T2D in PCP and specialty care, greater reduction in HbA 1c and increased glycemic control durability were observed with liraglutide in primary care, compared with specialist care. These data suggest that liraglutide treatment could benefit patients in primary care by delaying the need for further treatment

World Hip Trauma Evaluation (WHiTE): framework for embedded comprehensive cohort studies.

PubMed

Costa, Matthew L; Griffin, Xavier L; Achten, Juul; Metcalfe, David; Judge, Andrew; Pinedo-Villanueva, Rafael; Parsons, Nicholas

2016-10-21

Osteoporotic hip fractures present a significant global challenge to patients, clinicians and healthcare systems. It is estimated that hip fracture accounts for 1.4% of total social and healthcare costs in the established market economies. The World Hip Trauma Evaluation (WHiTE) was set up to measure outcome in a comprehensive cohort of UK patients with hip fracture. All patients in the cohort are treated under a single comprehensive treatment pathway. A core outcome set, including health-related quality of life, is collected on all the patients. This protocol describes the current multicentre project that will be used as a vehicle to deliver a series of embedded observational studies. Research Ethics Committee approval was granted (Rec reference 11/LO/0927, approved 18/8/2011) and each hospital trust provided National Health Service (NHS) approvals. The study is registered with National Institute of Health Research Portfolio (UKCRN ID 12351) and the ISRCTN registry (ISRCTN63982700). 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/.

Use of atomoxetine and suicidal ideation in children and adolescents: Results of an observational cohort study within general practice in England.

PubMed

Davies, M; Coughtrie, A; Layton, D; Shakir, S A S

2017-01-01

To investigate the association between atomoxetine, a drug used in the treatment of Attention Deficit Hyperactivity Disorder (ADHD), and suicidal ideation, within a cohort of 2-18-year-old patients in England. The study was conducted using the observational cohort technique of Modified prescription event monitoring (M-PEM). Patients prescribed atomoxetine were identified from dispensed prescriptions issued by primary care physicians. A customised postal GP questionnaire was used to capture outcome data for suicidal ideation. A matched pair cohort analysis was performed within patients to compare the risk of suicidal ideation in the period after starting atomoxetine with the risk prior to starting atomoxetine; this was stratified by age and concomitant use of methylphenidate. Additional information on patient characteristics, and events of interest was also collected; individual cases of suicidal ideation were qualitatively assessed for drug relatedness. Of the final cohort (n=4509); 85.5% male (n=3857), median age 11 years (IQR: 9,14). Primary prescribing indication for atomoxetine was ADHD (n=4261, 94.6%). Almost a quarter of the cohort had been co-prescribed methylphenidate. Results of the matched pair cohort analysis indicated that the period after starting atomoxetine was not associated with an increase in the incidence of suicidal ideation compared to the period prior to starting treatment (RR: 0.71; CI: 0.48-1.07; P-value: 0.104). Individual case assessment of suicidal ideation suggested a causal association within a number of cases. This study found no evidence of an increased risk of suicidal ideation during treatment with atomoxetine, compared to the period prior to starting treatment. Amongst age specific subgroups, this risk may change. Nonetheless, individual case assessment suggested a causal relationship in some patients, hence physicians need to be aware of the possibility of developing this event, and furthermore consider how best to detect it in

Inference and quantification of peptidoforms in large sample cohorts by SWATH-MS

PubMed Central

Röst, Hannes L; Ludwig, Christina; Buil, Alfonso; Bensimon, Ariel; Soste, Martin; Spector, Tim D; Dermitzakis, Emmanouil T; Collins, Ben C; Malmström, Lars; Aebersold, Ruedi

2017-01-01

The consistent detection and quantification of protein post-translational modifications (PTMs) across sample cohorts is an essential prerequisite for the functional analysis of biological processes. Data-independent acquisition (DIA), a bottom-up mass spectrometry based proteomic strategy, exemplified by SWATH-MS, provides complete precursor and fragment ion information of a sample and thus, in principle, the information to identify peptidoforms, the modified variants of a peptide. However, due to the convoluted structure of DIA data sets the confident and systematic identification and quantification of peptidoforms has remained challenging. Here we present IPF (Inference of PeptidoForms), a fully automated algorithm that uses spectral libraries to query, validate and quantify peptidoforms in DIA data sets. The method was developed on data acquired by SWATH-MS and benchmarked using a synthetic phosphopeptide reference data set and phosphopeptide-enriched samples. The data indicate that IPF reduced false site-localization by more than 7-fold in comparison to previous approaches, while recovering 85.4% of the true signals. IPF was applied to detect and quantify peptidoforms carrying ten different types of PTMs in DIA data acquired from more than 200 samples of undepleted blood plasma of a human twin cohort. The data approportioned, for the first time, the contribution of heritable, environmental and longitudinal effects on the observed quantitative variability of specific modifications in blood plasma of a human population. PMID:28604659

Lymphoproliferative disorders in patients receiving thiopurines for inflammatory bowel disease: a prospective observational cohort study.

PubMed

Beaugerie, Laurent; Brousse, Nicole; Bouvier, Anne Marie; Colombel, Jean Frédéric; Lémann, Marc; Cosnes, Jacques; Hébuterne, Xavier; Cortot, Antoine; Bouhnik, Yoram; Gendre, Jean Pierre; Simon, Tabassome; Maynadié, Marc; Hermine, Olivier; Faivre, Jean; Carrat, Fabrice

2009-11-07

Reports of an increased risk of lymphoproliferative disorders in patients receiving thiopurines for inflammatory bowel disease are controversial. We assessed this risk in a prospective observational cohort study. 19,486 patients with inflammatory bowel disease, of whom 11,759 (60.3%) had Crohn's disease and 7727 (39.7%) had ulcerative colitis or unclassified inflammatory bowel disease, were enrolled in a nationwide French cohort by 680 gastroenterologists, who reported details of immunosuppressive therapy during the observation period, cases of cancer, and deaths. The risk of lymphoproliferative disorder was assessed according to thiopurine exposure. Median follow-up was 35 months (IQR 29-40). At baseline, 5867 (30.1%) of patients were receiving, 2809 (14.4%) had discontinued, and 10,810 (55.5%) had never received thiopurines. 23 new cases of lymphoproliferative disorder were diagnosed, consisting of one case of Hodgkin's lymphoma and 22 cases of non-Hodgkin lymphoproliferative disorder. The incidence rates of lymphoproliferative disorder were 0.90 per 1000 (95% CI 0.50-1.49) patient-years in those receiving, 0.20/1000 (0.02-0.72) patient-years in those who had discontinued, and 0.26/1000 (0.10-0.57) patient-years in those who had never received thiopurines (p=0.0054). The multivariate-adjusted hazard ratio of lymphoproliferative disorder between patients receiving thiopurines and those who had never received the drugs was 5.28 (2.01-13.9, p=0.0007). Most cases associated with thiopurine exposure matched the pathological range of post-transplant disease. Patients receiving thiopurines for inflammatory bowel disease have an increased risk of developing lymphoproliferative disorders. Programme Hospitalier de Recherche Clinique National (AOM05157), Association François Aupetit, Délégation Inter-régionale de la Recherche clinique Ile de France-Assistance Publique Hôpitaux de Paris (AP-HP), Ligue contre le Cancer, and Fonds de Recherche de la Société Nationale

Characteristics of children and adolescents first prescribed proton pump inhibitors or histamine-2-receptor antagonists: an observational cohort study.

PubMed

Ruigómez, Ana; Kool-Houweling, Leanne M A; García Rodríguez, Luis A; Penning-van Beest, Fernie J A; Herings, Ron M C

2017-12-01

To describe the characteristics of pediatric patients prescribed proton pump inhibitors (PPIs) vs those of pediatric patients prescribed histamine-2-receptor antagonists (H 2 RAs). Observational studies were conducted using The Health Improvement Network (THIN) and the PHARMO Database Network. Patients aged 0-18 years who were first prescribed a PPI or H 2 RA between October 1, 2009 and September 30, 2012 (THIN) or between September 1, 2008 and August 31, 2011 (PHARMO) were included. Patient characteristics were identified and compared between the PPI and H 2 RA cohorts using odds ratios (ORs) and 95% confidence intervals (CIs) adjusted for age and sex. The mean age (years) was higher in the PPI than in the H 2 RA cohorts (THIN 12.3 [n = 8204] vs 5.4 [n = 7937], PHARMO 11.0 [n = 15 362] vs 7.1 [n = 6168]). Previous respiratory disease was more common in the PPI than in the H 2 RA cohort in THIN (OR = 1.19, 95% CI = 1.08-1.30), as were asthma and respiratory medication use in PHARMO (OR = 1.27, 95% CI = 1.12-1.45 and OR = 1.23, 95% CI = 1.10-1.38, respectively) and oral corticosteroid use in both databases (OR = 1.45, 95% CI = 1.10-1.92 [THIN]; OR = 2.80, 95% CI = 2.11-3.71 [PHARMO]). Non-steroidal anti-inflammatory drugs, antibiotics, and oral contraceptives were also more common in PPI than in H 2 RA cohorts in both databases. Pediatric patients receiving PPIs and those receiving H 2 RAs may represent different patient populations. PPIs may be more commonly prescribed than H 2 RAs among patients with respiratory diseases.

Observational cohort study of the natural history of Niemann-Pick disease type C in the UK: a 5-year update from the UK clinical database.

PubMed

Imrie, Jackie; Heptinstall, Lesley; Knight, Stephen; Strong, Kate

2015-12-15

Niemann-Pick disease type C (NP-C) is a rare neurovisceral lipid storage disorder characterised by progressive, disabling neurological symptoms and premature death in most patients. During the last decade, national cohort studies have accrued a great deal of data on the symptomatology and natural history of NP-C. In an observational cohort study, we present a substantial update based on the clinical presentation and follow-up of all known UK-based patients with a confirmed diagnosis of NP-C who have been tracked on an electronic database at the Department of Genetic Medicine, University of Manchester, UK. Patients were stratified according to accepted age-at-neurological-onset categories. Data on patients' clinical signs and symptoms, medical history and genetic studies are summarised using descriptive methods. A total of 146 patients with NP-C were included, representing the full known UK NP-C cohort, as observed from database information between 1999 and the end of 2011: 72 patients (49 %) were alive at the end of the observation period. Among a total of 116 patients (79 %) who possessed at least one identified, disease-causing NP-C gene mutation, 114 (98 %) had NPC1 and two (2 %) had NPC2 mutations. Overall, 53/194 (27 %) identified mutations were novel. Six patients (4 %) had an early, non-neurological neonatal onset form of NP-C. The numbers (%) of patients with accepted age-at-neurological onset forms were: 8 (5 %) early-infantile onset, 51 (35 %) late-infantile onset, 42 (29 %) juvenile onset, and 25 (17 %) adolescent/adult onset. Fourteen patients diagnosed based on visceral symptoms and/or sibling history, confirmed in most cases by genetic analysis, did not have any neurological manifestations at last follow up (11 patients with mean [SD] age at last follow up 2.5 [1.8] years: 3 with mean [SD] age at death 20.8 [15.9] years). A total of 51 patients (35 %) received miglustat therapy. The mean (SD) overall treatment duration up to the end of the

Comparison of bias analysis strategies applied to a large data set.

PubMed

Lash, Timothy L; Abrams, Barbara; Bodnar, Lisa M

2014-07-01

Epidemiologic data sets continue to grow larger. Probabilistic-bias analyses, which simulate hundreds of thousands of replications of the original data set, may challenge desktop computational resources. We implemented a probabilistic-bias analysis to evaluate the direction, magnitude, and uncertainty of the bias arising from misclassification of prepregnancy body mass index when studying its association with early preterm birth in a cohort of 773,625 singleton births. We compared 3 bias analysis strategies: (1) using the full cohort, (2) using a case-cohort design, and (3) weighting records by their frequency in the full cohort. Underweight and overweight mothers were more likely to deliver early preterm. A validation substudy demonstrated misclassification of prepregnancy body mass index derived from birth certificates. Probabilistic-bias analyses suggested that the association between underweight and early preterm birth was overestimated by the conventional approach, whereas the associations between overweight categories and early preterm birth were underestimated. The 3 bias analyses yielded equivalent results and challenged our typical desktop computing environment. Analyses applied to the full cohort, case cohort, and weighted full cohort required 7.75 days and 4 terabytes, 15.8 hours and 287 gigabytes, and 8.5 hours and 202 gigabytes, respectively. Large epidemiologic data sets often include variables that are imperfectly measured, often because data were collected for other purposes. Probabilistic-bias analysis allows quantification of errors but may be difficult in a desktop computing environment. Solutions that allow these analyses in this environment can be achieved without new hardware and within reasonable computational time frames.

Station Set Residual: Event Classification Using Historical Distribution of Observing Stations

NASA Astrophysics Data System (ADS)

Procopio, Mike; Lewis, Jennifer; Young, Chris

2010-05-01

Analysts working at the International Data Centre in support of treaty monitoring through the Comprehensive Nuclear-Test-Ban Treaty Organization spend a significant amount of time reviewing hypothesized seismic events produced by an automatic processing system. When reviewing these events to determine their legitimacy, analysts take a variety of approaches that rely heavily on training and past experience. One method used by analysts to gauge the validity of an event involves examining the set of stations involved in the detection of an event. In particular, leveraging past experience, an analyst can say that an event located in a certain part of the world is expected to be detected by Stations A, B, and C. Implicit in this statement is that such an event would usually not be detected by Stations X, Y, or Z. For some well understood parts of the world, the absence of one or more "expected" stations—or the presence of one or more "unexpected" stations—is correlated with a hypothesized event's legitimacy and to its survival to the event bulletin. The primary objective of this research is to formalize and quantify the difference between the observed set of stations detecting some hypothesized event, versus the expected set of stations historically associated with detecting similar nearby events close in magnitude. This Station Set Residual can be quantified in many ways, some of which are correlated with the analysts' determination of whether or not the event is valid. We propose that this Station Set Residual score can be used to screen out certain classes of "false" events produced by automatic processing with a high degree of confidence, reducing the analyst burden. Moreover, we propose that the visualization of the historically expected distribution of detecting stations can be immediately useful as an analyst aid during their review process.

Interval between onset of psoriasis and psoriatic arthritis comparing the UK Clinical Practice Research Datalink with a hospital-based cohort.

PubMed

Tillett, William; Charlton, Rachel; Nightingale, Alison; Snowball, Julia; Green, Amelia; Smith, Catherine; Shaddick, Gavin; McHugh, Neil

2017-12-01

To describe the time interval between the onset of psoriasis and PsA in the UK primary care setting and compare with a large, well-classified secondary care cohort. Patients with PsA and/or psoriasis were identified in the UK Clinical Practice Research Datalink (CPRD). The secondary care cohort comprised patients from the Bath PsA longitudinal observational cohort study. For incident PsA patients in the CPRD who also had a record of psoriasis, the time interval between PsA diagnosis and first psoriasis record was calculated. Comparisons were made with the time interval between diagnoses in the Bath cohort. There were 5272 eligible PsA patients in the CPRD and 815 in the Bath cohort. In both cohorts, the majority of patients (82.3 and 61.3%, respectively) had psoriasis before their PsA diagnosis or within the same calendar year (10.5 and 23.8%), with only a minority receiving their PsA diagnosis first (7.1 and 14.8%). Excluding those who presented with arthritis before psoriasis, the median time between diagnoses was 8 years [interquartile range (IQR) 2-15] in the CPRD and 7 years (IQR 0-20) in the Bath cohort. In the CPRD, 60.1 and 75.1% received their PsA diagnosis within 10 and 15 years of their psoriasis diagnosis, respectively; this was comparable with 57.2 and 67.7% in the Bath cohort. A similar distribution for the time interval between psoriasis and arthritis was observed in the CPRD and secondary care cohort. These data can inform screening strategies and support the validity of data from each cohort. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Case-Cohort Studies: Design and Applicability to Hand Surgery.

PubMed

Vojvodic, Miliana; Shafarenko, Mark; McCabe, Steven J

2018-04-24

Observational studies are common research strategies in hand surgery. The case-cohort design offers an efficient and resource-friendly method for risk assessment and outcomes analysis. Case-cohorts remain underrepresented in upper extremity research despite several practical and economic advantages over case-control studies. This report outlines the purpose, utility, and structure of the case-cohort design and offers a sample research question to demonstrate its value to risk estimation for adverse surgical outcomes. The application of well-designed case-cohort studies is advocated in an effort to improve the quality and quantity of observational research evidence in hand and upper extremity surgery. Copyright © 2018 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Descriptive epidemiology and prior healthcare utilization of patients in the Spine Patient Outcomes Research Trial's (SPORT) three observational cohorts: disc herniation, spinal stenosis, and degenerative spondylolisthesis.

PubMed

Cummins, Justin; Lurie, Jon D; Tosteson, Tor D; Hanscom, Brett; Abdu, William A; Birkmeyer, Nancy J O; Herkowitz, Harry; Weinstein, James

2006-04-01

Prospective observational cohorts. To describe sociodemographic and clinical features, and nonoperative (medical) resource utilization before enrollment, in patients who are candidates for surgical intervention for intervertebral disc herniation (IDH), spinal stenosis (SpS), and degenerative spondylolisthesis (DS) according to SPORT criteria. Intervertebral disc herniation, spinal stenosis, and degenerative spondylolisthesis with stenosis are the three most common diagnoses of low back and leg symptoms for which surgery is performed. There is a paucity of descriptive literature examining large patient cohorts for the relationships among baseline characteristics and medical resource utilization with these three diagnoses. The Spine Patient Outcomes Research Trial (SPORT) conducts three randomized and three observational cohort studies of surgical and nonsurgical treatments for patients with IDH, SpS, and DS. Baseline data include demographic information, prior treatments received, and functional status measured by SF-36 and the Oswestry Disability Index (ODI-AAOS/Modems version). The data presented represent all 1,411 patients (743 IDH, 365 SpS, 303 DS) enrolled in the SPORT observational cohorts. Multiple logistic regression was used to generate independent predictors of utilization adjusted for sociodemographic variables, diagnosis, and duration of symptoms. The average age was 41 years for the IDH group, 64 years for the SpS group, and 66 years for the DS group. At enrollment, IDH patients presented with the most pain as reported on the SF-36 (BP 26.3 vs. 33.2 SpS and 33.8 DS) and were the most impaired (ODI 51 vs. 42.3 SpS and 41.5 DS). IDH patients used more chiropractic treatment (42% vs. 33% SpS and 26% DS), had more Emergency Department (ED) visits (21% vs. 7% SpS and 4% DS), and used more opiate analgesics (49% vs. 29% SpS and 27% DS). After adjusting for age, gender, diagnosis, education, race, duration of symptoms, and compensation, Medicaid patients used

Analysis of cohort studies with multivariate and partially observed disease classification data.

PubMed

Chatterjee, Nilanjan; Sinha, Samiran; Diver, W Ryan; Feigelson, Heather Spencer

2010-09-01

Complex diseases like cancers can often be classified into subtypes using various pathological and molecular traits of the disease. In this article, we develop methods for analysis of disease incidence in cohort studies incorporating data on multiple disease traits using a two-stage semiparametric Cox proportional hazards regression model that allows one to examine the heterogeneity in the effect of the covariates by the levels of the different disease traits. For inference in the presence of missing disease traits, we propose a generalization of an estimating equation approach for handling missing cause of failure in competing-risk data. We prove asymptotic unbiasedness of the estimating equation method under a general missing-at-random assumption and propose a novel influence-function-based sandwich variance estimator. The methods are illustrated using simulation studies and a real data application involving the Cancer Prevention Study II nutrition cohort.

South Yorkshire Cohort: a 'cohort trials facility' study of health and weight - protocol for the recruitment phase.

PubMed

Relton, Clare; Bissell, Paul; Smith, Christine; Blackburn, Joanna; Cooper, Cindy L; Nicholl, Jon; Tod, Angela; Copeland, Rob; Loban, Amanda; Chater, Tim; Thomas, Kate; Young, Tracy; Weir, Carol; Harrison, Gill; Millbourn, Alison; Manners, Rachel

2011-08-11

Growing levels of both obesity and chronic disease in the general population pose a major public health problem. In the UK, an innovative 'health and weight' cohort trials facility, the 'South Yorkshire Cohort', is being built in order to provide robust evidence to inform policy, commissioning and clinical decisions in this field. This protocol reports the design of the facility and outlines the recruitment phase methods. The South Yorkshire Cohort health and weight study uses the cohort multiple randomised controlled trial design. This design recruits a large observational cohort of patients with the condition(s) of interest which then provides a facility for multiple randomised controlled trials (with large representative samples of participants, long term outcomes as standard, increased comparability between each trial conducted within the cohort and increased efficiency particularly for trials of expensive interventions) as well as ongoing information as to the natural history of the condition and treatment as usual.This study aims to recruit 20,000 participants to the population based South Yorkshire Cohort health and weight research trials facility. Participants are recruited by invitation letters from their General Practitioners. Data is collected using postal and/or online patient self completed Health Questionnaires. NHS numbers will be used to facilitate record linkage and access to routine data. Participants are eligible if they are: aged 16 - 85 years, registered with one of 40 practices in South Yorkshire, provide consent for further contact from the researchers and to have their information used to look at the benefit of health treatments. The first wave of data is being collected during 2010/12 and further waves are planned at 2 - 5 year intervals for the planned 20 year duration of the facility. The South Yorkshire Cohort combines the strengths of the standard observational, longitudinal cohort study design with a population based cohort facility

South Yorkshire Cohort: a 'cohort trials facility' study of health and weight - Protocol for the recruitment phase

PubMed Central

2011-01-01

Background Growing levels of both obesity and chronic disease in the general population pose a major public health problem. In the UK, an innovative 'health and weight' cohort trials facility, the 'South Yorkshire Cohort', is being built in order to provide robust evidence to inform policy, commissioning and clinical decisions in this field. This protocol reports the design of the facility and outlines the recruitment phase methods. Method/Design The South Yorkshire Cohort health and weight study uses the cohort multiple randomised controlled trial design. This design recruits a large observational cohort of patients with the condition(s) of interest which then provides a facility for multiple randomised controlled trials (with large representative samples of participants, long term outcomes as standard, increased comparability between each trial conducted within the cohort and increased efficiency particularly for trials of expensive interventions) as well as ongoing information as to the natural history of the condition and treatment as usual. This study aims to recruit 20,000 participants to the population based South Yorkshire Cohort health and weight research trials facility. Participants are recruited by invitation letters from their General Practitioners. Data is collected using postal and/or online patient self completed Health Questionnaires. NHS numbers will be used to facilitate record linkage and access to routine data. Participants are eligible if they are: aged 16 - 85 years, registered with one of 40 practices in South Yorkshire, provide consent for further contact from the researchers and to have their information used to look at the benefit of health treatments. The first wave of data is being collected during 2010/12 and further waves are planned at 2 - 5 year intervals for the planned 20 year duration of the facility. Discussion The South Yorkshire Cohort combines the strengths of the standard observational, longitudinal cohort study design with

Candida Infective Endocarditis: an Observational Cohort Study with a Focus on Therapy

PubMed Central

Johnson, Melissa; Bayer, Arnold S.; Bradley, Suzanne; Giannitsioti, Efthymia; Miró, José M.; Tornos, Pilar; Tattevin, Pierre; Strahilevitz, Jacob; Spelman, Denis; Athan, Eugene; Nacinovich, Francisco; Fortes, Claudio Q.; Lamas, Cristiane; Barsic, Bruno; Fernández-Hidalgo, Nuria; Muñoz, Patricia; Chu, Vivian H.

2015-01-01

Candida infective endocarditis is a rare disease with a high mortality rate. Our understanding of this infection is derived from case series, case reports, and small prospective cohorts. The purpose of this study was to evaluate the clinical features and use of different antifungal treatment regimens for Candida infective endocarditis. This prospective cohort study was based on 70 cases of Candida infective endocarditis from the International Collaboration on Endocarditis (ICE)-Prospective Cohort Study and ICE-Plus databases collected between 2000 and 2010. The majority of infections were acquired nosocomially (67%). Congestive heart failure (24%), prosthetic heart valve (46%), and previous infective endocarditis (26%) were common comorbidities. Overall mortality was high, with 36% mortality in the hospital and 59% at 1 year. On univariate analysis, older age, heart failure at baseline, persistent candidemia, nosocomial acquisition, heart failure as a complication, and intracardiac abscess were associated with higher mortality. Mortality was not affected by use of surgical therapy or choice of antifungal agent. A subgroup analysis was performed on 33 patients for whom specific antifungal therapy information was available. In this subgroup, 11 patients received amphotericin B-based therapy and 14 received echinocandin-based therapy. Despite a higher percentage of older patients and nosocomial infection in the echinocandin group, mortality rates were similar between the two groups. In conclusion, Candida infective endocarditis is associated with a high mortality rate that was not impacted by choice of antifungal therapy or by adjunctive surgical intervention. Additionally, echinocandin therapy was as effective as amphotericin B-based therapy in the small subgroup analysis. PMID:25645855

Risk factors for acute exacerbations of COPD in a primary care population: a retrospective observational cohort study.

PubMed

Müllerová, Hana; Shukla, Amit; Hawkins, Adam; Quint, Jennifer

2014-12-18

To evaluate risk factors associated with exacerbation frequency in primary care. Information on exacerbations of chronic obstructive pulmonary disease (COPD) has mainly been generated by secondary care-based clinical cohorts. Retrospective observational cohort study. Electronic medical records database (England and Wales). 58,589 patients with COPD aged ≥40 years with COPD diagnosis recorded between 1 April 2009 and 30 September 2012, and with at least 365 days of follow-up before and after the COPD diagnosis, were identified in the Clinical Practice Research Datalink. Mean age: 69 years; 47% female; mean forced expiratory volume in 1s 60% predicted. Data on moderate or severe exacerbation episodes defined by diagnosis and/or medication codes 12 months following cohort entry were retrieved, together with demographic and clinical characteristics. Associations between patient characteristics and odds of having none versus one, none versus frequent (≥2) and one versus frequent exacerbations over 12 months follow-up were evaluated using multivariate logistic regression models. During follow-up, 23% of patients had evidence of frequent moderate-to-severe COPD exacerbations (24% one; 53% none). Independent predictors of increased odds of having exacerbations during the follow-up, either frequent episodes or one episode, included prior exacerbations, increasing dyspnoea score, increasing grade of airflow limitation, females and prior or current history of several comorbidities (eg, asthma, depression, anxiety, heart failure and cancer). Primary care-managed patients with COPD at the highest risk of exacerbations can be identified by exploring medical history for the presence of prior exacerbations, greater COPD disease severity and co-occurrence of other medical conditions. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

The impact of unstable housing on emergency department use in a cohort of HIV-positive people in a Canadian setting

PubMed Central

Chan, Keith; Milan, David; Grafstein, Eric; Palmer, Alexis K.; Rhodes, Chelsey; Montaner, Julio S.G.; Hogg, Robert S.

2014-01-01

The social-structural challenges experienced by people living with HIV (PHA) have been shown to contribute to increased use of the Emergency Department (ED). This study identified factors associated with frequent and non-urgent ED use within a cohort of people accessing antiretroviral therapy (ART) in a Canadian setting. Interviewer-administered surveys collected socio-demographic information; clinical variables were obtained through linkages with the provincial drug treatment registry; and ED admission data were abstracted from the Department of Emergency Medicine database. Multivariate logistic regression was used to compute odds of frequent and non-urgent ED use. Unstable housing was independently associated with ED use (adjusted odds ratio [AOR]=1.94, 95% confidence interval [CI] 1.24–3.04]), having three or more ED visits within 6 months of interview date [AOR: 2.03 (95% CI: 1.07–3.83)] and being triaged as non-urgent (AOR=2.71, 95% CI: 1.19–6.17). Frequent and non-urgent use of the ED in this setting is associated with conditions requiring interventions at the social-structural level. Supportive housing may contribute to decreased healthcare costs and improved health outcomes amongst marginalized PHA. PMID:23656484

A cohort study of influences, health outcomes and costs of patients' health-seeking behaviour for minor ailments from primary and emergency care settings.

PubMed

Watson, M C; Ferguson, J; Barton, G R; Maskrey, V; Blyth, A; Paudyal, V; Bond, C M; Holland, R; Porteous, T; Sach, T H; Wright, D; Fielding, S

2015-02-18

To compare health-related and cost-related outcomes of consultations for symptoms suggestive of minor ailments in emergency departments (EDs), general practices and community pharmacies. Observational study; prospective cohort design. EDs (n=2), general practices (n=6) and community pharmacies (n=10) in a mix of rural/urban and deprived/affluent areas across North East Scotland and East Anglia. Participants Adults (≥18 years) presenting between 09:00 and 18:00 (Monday-Friday) in general practices and 09:00-18:00 (Monday-Saturday) in pharmacies and EDs with ≥1 of the following: musculoskeletal pain; eye discomfort; gastrointestinal disturbance; or upper respiratory tract-related symptoms. Participants completed three questionnaires: baseline (prior to index consultation); satisfaction with index consultation and follow-up (2 weeks after index consultation). Symptom resolution, quality of life, costs, satisfaction and influences on care-seeking behaviour. 377 patients participated, recruited from EDs (81), general practices (162) and community pharmacies (134). The 2-week response rate was 70% (264/377). Symptom resolution was similar across all three settings: ED (37.3%), general practice (35.7%) and pharmacy (44.3%). Mean overall costs per consultation were significantly lower for pharmacy (£29.30 (95% CI £21.60 to £37.00)) compared with general practice (£82.34 (95% CI £63.10 to £101.58)) and ED (£147.09 (95% CI £125.32 to £168.85)). Satisfaction varied across settings and by measure used. Compared with pharmacy and general practice use, ED use was significantly (p<0.001) associated with first episode and short duration of symptom(s), as well as higher levels of perceived seriousness and urgency for seeking care. Convenience of location was the most common reason for choice of consultation setting. These results suggest similar health-related outcomes and substantially lower costs with pharmacy consultations for minor ailments. Effective

Cohort fertility in Western Europe: comparing fertility trends in recent birth cohorts.

PubMed

Hopflinger, F

1984-01-01

A comparative study of fertility levels among cohorts of women born in 1940, 1945, 1950, 1955, and 1960 in 16 European countries was undertaken using vital statistics data. The average number of live birth/woman for each of the 5 cohorts by age 20, 25, 30, and 35 was computed by cumulating age-specific fertility rates of women born in specific years. Median age at childbirth and completed fertility were estimated for the 3 oldest cohorts (1940, 1945, and 1950). 2 estimations of completed fertility were made. 1 was based on the assumption of a constant age-specific fertility rate, and the other was based on a relational Gompertz model. Where possible cohort fertility was disaggregated by birth order. Since the data for the countries was not fully comparable, it was not possible to use sophisticated analytical techniques. Other limits of the study were that fertility, especially for the more recent cohorts was incomplete, parity specific data was not available for all the countries, and open cohorts rather than closed cohorts were used. The analysis indicated that completed cohort fertility was lower for the 1950 cohort than for the 1940 cohort in all 16 countries. For the 1940 cohort, only Germany's estimated completed fertility was less than 2.00. For the other 15 countries, estimated completed fertility ranged from 2.04 (Finland) to 3.36 (Ireland). For the 1950 cohort, estimated completed fertility was less than 2.00 in 8 of the countries. Estimated completed fertility was lowest in Finland and Switzerland (1.82) and highest in Ireland (3.33). No marked increase in childlessness was observed, and for the 1940 and 1950 cohorts, childlessness did not exceed 20% in any of the countries and was considerably less than 20% in most of the countries. There was a trend toward delayed childbearing in most of the countries. An examination of available parity data for the 1940 and 1950 cohorts lead to the conclusion that the major factor contributing toward the decline in

Analysis of Clinical Cohort Data Using Nested Case-control and Case-cohort Sampling Designs. A Powerful and Economical Tool.

PubMed

Ohneberg, K; Wolkewitz, M; Beyersmann, J; Palomar-Martinez, M; Olaechea-Astigarraga, P; Alvarez-Lerma, F; Schumacher, M

2015-01-01

Sampling from a large cohort in order to derive a subsample that would be sufficient for statistical analysis is a frequently used method for handling large data sets in epidemiological studies with limited resources for exposure measurement. For clinical studies however, when interest is in the influence of a potential risk factor, cohort studies are often the first choice with all individuals entering the analysis. Our aim is to close the gap between epidemiological and clinical studies with respect to design and power considerations. Schoenfeld's formula for the number of events required for a Cox' proportional hazards model is fundamental. Our objective is to compare the power of analyzing the full cohort and the power of a nested case-control and a case-cohort design. We compare formulas for power for sampling designs and cohort studies. In our data example we simultaneously apply a nested case-control design with a varying number of controls matched to each case, a case cohort design with varying subcohort size, a random subsample and a full cohort analysis. For each design we calculate the standard error for estimated regression coefficients and the mean number of distinct persons, for whom covariate information is required. The formula for the power of a nested case-control design and the power of a case-cohort design is directly connected to the power of a cohort study using the well known Schoenfeld formula. The loss in precision of parameter estimates is relatively small compared to the saving in resources. Nested case-control and case-cohort studies, but not random subsamples yield an attractive alternative for analyzing clinical studies in the situation of a low event rate. Power calculations can be conducted straightforwardly to quantify the loss of power compared to the savings in the num-ber of patients using a sampling design instead of analyzing the full cohort.

Global teaching and training initiatives for emerging cohort studies

PubMed Central

Paulus, Jessica K.; Santoyo-Vistrain, Rocío; Havelick, David; Cohen, Amy; Kalyesubula, Robert; Ajayi, Ikeoluwapo O.; Mattsson, Jens G.; Adami, Hans-Olov; Dalal, Shona

2015-01-01

A striking disparity exists across the globe, with essentially no large-scale longitudinal studies ongoing in regions that will be significantly affected by the oncoming non-communicable disease epidemic. The successful implementation of cohort studies in most low-resource research environments presents unique challenges that may be aided by coordinated training programs. Leaders of emerging cohort studies attending the First World Cohort Integration Workshop were surveyed about training priorities, unmet needs and potential cross-cohort solutions to these barriers through an electronic pre-workshop questionnaire and focus groups. Cohort studies representing India, Mexico, Nigeria, South Africa, Sweden, Tanzania and Uganda described similar training needs, including on-the-job training, data analysis software instruction, and database and bio-bank management. A lack of funding and protected time for training activities were commonly identified constraints. Proposed solutions include a collaborative cross-cohort teaching platform with web-based content and interactive teaching methods for a range of research personnel. An international network for research mentorship and idea exchange, and modifying the graduate thesis structure were also identified as key initiatives. Cross-cohort integrated educational initiatives will efficiently meet shared needs, catalyze the development of emerging cohorts, speed closure of the global disparity in cohort research, and may fortify scientific capacity development in low-resource settings. PMID:23856451

The "DGPPN-Cohort": A national collaboration initiative by the German Association for Psychiatry and Psychotherapy (DGPPN) for establishing a large-scale cohort of psychiatric patients.

PubMed

Anderson-Schmidt, Heike; Adler, Lothar; Aly, Chadiga; Anghelescu, Ion-George; Bauer, Michael; Baumgärtner, Jessica; Becker, Joachim; Bianco, Roswitha; Becker, Thomas; Bitter, Cosima; Bönsch, Dominikus; Buckow, Karoline; Budde, Monika; Bührig, Martin; Deckert, Jürgen; Demiroglu, Sara Y; Dietrich, Detlef; Dümpelmann, Michael; Engelhardt, Uta; Fallgatter, Andreas J; Feldhaus, Daniel; Figge, Christian; Folkerts, Here; Franz, Michael; Gade, Katrin; Gaebel, Wolfgang; Grabe, Hans-Jörgen; Gruber, Oliver; Gullatz, Verena; Gusky, Linda; Heilbronner, Urs; Helbing, Krister; Hegerl, Ulrich; Heinz, Andreas; Hensch, Tilman; Hiemke, Christoph; Jäger, Markus; Jahn-Brodmann, Anke; Juckel, Georg; Kandulski, Franz; Kaschka, Wolfgang P; Kircher, Tilo; Koller, Manfred; Konrad, Carsten; Kornhuber, Johannes; Krause, Marina; Krug, Axel; Lee, Mahsa; Leweke, Markus; Lieb, Klaus; Mammes, Mechthild; Meyer-Lindenberg, Andreas; Mühlbacher, Moritz; Müller, Matthias J; Nieratschker, Vanessa; Nierste, Barbara; Ohle, Jacqueline; Pfennig, Andrea; Pieper, Marlenna; Quade, Matthias; Reich-Erkelenz, Daniela; Reif, Andreas; Reitt, Markus; Reininghaus, Bernd; Reininghaus, Eva Z; Riemenschneider, Matthias; Rienhoff, Otto; Roser, Patrik; Rujescu, Dan; Schennach, Rebecca; Scherk, Harald; Schmauss, Max; Schneider, Frank; Schosser, Alexandra; Schott, Björn H; Schwab, Sybille G; Schwanke, Jens; Skrowny, Daniela; Spitzer, Carsten; Stierl, Sebastian; Stöckel, Judith; Stübner, Susanne; Thiel, Andreas; Volz, Hans-Peter; von Hagen, Martin; Walter, Henrik; Witt, Stephanie H; Wobrock, Thomas; Zielasek, Jürgen; Zimmermann, Jörg; Zitzelsberger, Antje; Maier, Wolfgang; Falkai, Peter G; Rietschel, Marcella; Schulze, Thomas G

2013-12-01

The German Association for Psychiatry and Psychotherapy (DGPPN) has committed itself to establish a prospective national cohort of patients with major psychiatric disorders, the so-called DGPPN-Cohort. This project will enable the scientific exploitation of high-quality data and biomaterial from psychiatric patients for research. It will be set up using harmonised data sets and procedures for sample generation and guided by transparent rules for data access and data sharing regarding the central research database. While the main focus lies on biological research, it will be open to all kinds of scientific investigations, including epidemiological, clinical or health-service research.

Risk factors for dermatitis in submariners during a submerged patrol: an observational cohort study.

PubMed

Flaxman, Amy; Allen, Elizabeth; Lindemann, Claudia; Yamaguchi, Yuko; O'Shea, Matthew K; Fallowfield, Joanne L; Lindsay, Michael; Gunner, Frances; Knox, Kyle; Wyllie, David H

2016-06-02

The aim of this pilot study was to determine risk factors, including Staphylococcus aureus nasal carriage, for dermatitis in submariners during a submarine patrol. 36 submariners undertaking a submerged 6-week patrol participated in the study. Severity of dermatitis and its impact was assessed using visual analogue scales and questionnaires at baseline and weekly throughout the patrol. S. aureus carriage levels in submariners were determined by nasal swabbing at baseline and shortly before disembarking the submarine. Occurrence of any skin or soft tissue infections (SSTI) were reported to the medical officer and swabs of the area were taken for subsequent analysis. S. aureus carriers were significantly more likely than non-carriers to have previously received treatment for a cutaneous abscess (39% vs 5%, OR=13 (95% CI 1.3 to 130)) with a trend to being submariners longer (p=0.051). Skin scores at baseline and on patrol were not significantly associated with carriage status. Higher dermatitis scores were observed in those who had been submariners longer (p=0.045). Smoking and allergies were not found to be linked to carriage status or skin health score in this cohort. This small pilot study investigates S. aureus carriage status and skin health in submariners. Length of submarine service but not S. aureus carriage was identified as a risk factor for worsening skin health in this small cohort during a 6-week patrol. This does not support S. aureus decolonisation to improve skin health in this population. Further investigation into causes of dermatitis in submariners is required. This data supports a better understanding of the potential impact of exposure to environmental factors that could affect skin health in submariners. 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/

Historic cohort study in Montreal's fur industry.

PubMed

Guay, D; Siemiatycki, J

1987-01-01

A historic cohort mortality study was carried out among two groups of male workers in the Montreal fur industry: 263 dressers and dyers and 599 fur garment manufacturers. The first group is exposed to a very wide variety of chemicals used in tanning, cleaning, and dyeing fur, including substances considered to be carcinogenic and/or mutagenic. The second group is exposed to residue from the dressing and dyeing stage and to respirable fur dust. The cohorts consisted of all active members of two unions as of January 1, 1966. The mean age of the workers was 43.2 and the mean number of years since first employment 14.1. The follow-up period was from January 1, 1966, to December 31, 1981; 95% of the workers were successfully traced. Observed deaths were compared with those expected based on mortality rates of the population of metropolitan Montreal. Standardized mortality ratios (SMRs) for the manufacturers were significantly low, probably because of the ethnic composition of the cohort and a healthy worker effect. SMRs for the dressers and dyers were also low, but not as low as for the manufacturers. When attention was restricted to the French Canadians in the cohort, the observed deaths were close to the expected; there was a noteworthy excess of colorectal cancer (four observed, 0.8 expected) for dressers and dyers. Apart from this weak suggestive evidence, the results did not indicate any excess mortality risks in the fur industry. However, because of the relatively small number of expected and observed deaths in the cohort and especially among the heavily exposed dressers and dyers, the confidence intervals around SMR estimates were wide and excess risks cannot be ruled out.

Candida infective endocarditis: an observational cohort study with a focus on therapy.

PubMed

Arnold, Christopher J; Johnson, Melissa; Bayer, Arnold S; Bradley, Suzanne; Giannitsioti, Efthymia; Miró, José M; Tornos, Pilar; Tattevin, Pierre; Strahilevitz, Jacob; Spelman, Denis; Athan, Eugene; Nacinovich, Francisco; Fortes, Claudio Q; Lamas, Cristiane; Barsic, Bruno; Fernández-Hidalgo, Nuria; Muñoz, Patricia; Chu, Vivian H

2015-04-01

Candida infective endocarditis is a rare disease with a high mortality rate. Our understanding of this infection is derived from case series, case reports, and small prospective cohorts. The purpose of this study was to evaluate the clinical features and use of different antifungal treatment regimens for Candida infective endocarditis. This prospective cohort study was based on 70 cases of Candida infective endocarditis from the International Collaboration on Endocarditis (ICE)-Prospective Cohort Study and ICE-Plus databases collected between 2000 and 2010. The majority of infections were acquired nosocomially (67%). Congestive heart failure (24%), prosthetic heart valve (46%), and previous infective endocarditis (26%) were common comorbidities. Overall mortality was high, with 36% mortality in the hospital and 59% at 1 year. On univariate analysis, older age, heart failure at baseline, persistent candidemia, nosocomial acquisition, heart failure as a complication, and intracardiac abscess were associated with higher mortality. Mortality was not affected by use of surgical therapy or choice of antifungal agent. A subgroup analysis was performed on 33 patients for whom specific antifungal therapy information was available. In this subgroup, 11 patients received amphotericin B-based therapy and 14 received echinocandin-based therapy. Despite a higher percentage of older patients and nosocomial infection in the echinocandin group, mortality rates were similar between the two groups. In conclusion, Candida infective endocarditis is associated with a high mortality rate that was not impacted by choice of antifungal therapy or by adjunctive surgical intervention. Additionally, echinocandin therapy was as effective as amphotericin B-based therapy in the small subgroup analysis. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

[The BASYS observation system for the analysis of aggressive behavior in classroom-settings].

PubMed

Wettstein, Alexander

2012-01-01

Educational or therapeutic measures of aggressive student behavior are often based on the judgments of teachers. However, empirical studies show that the objectivity of these judgments is generally low. In order to assess aggressive behavior in classroom settings, we developed a context-sensitive observational system. The observation system exists in a version for teachers in action as well as a version for the uninvolved observer. The teacher version allows categorizing aggressive behavior while teaching. The aim is to differentiate the perception and the judgments of teachers, so that the judgments can serve as trustable diagnostic information. The version for an independent observer, in addition, contains categories to collect information about the context in which aggressions take place. The behavior observation system was tested in four field-studies in regular and special classes. The empirical results show that, after training, teachers were able to make objective observations, and that aggressive behavior depends to a large extent on situational factors. The system allows identification of problematic people-environment relationships and the derivation of intervention measures.

Fifteen years of dual polarimetric observations of tropical convection: The CPOL data set.

NASA Astrophysics Data System (ADS)

Collis, Scott; Protat, Alain; Jackson, Robert; Helmus, Jonathan; Giangrande, Scott; Louf, Valentin; Lang, Timothy; May, Peter; Glasson, Ken; Atkinson, Brad; Whimpey, Michael; Keenan, Tom

2017-04-01

The use of polarization diversity to measure properties of hydrometeors is not new and was first mentioned by Seliga and Bringi from an engineering perspective in 1976 and by Hendry et al (again in 1976) from a measurement perspective shortly thereafter. In the forty years that have passed since these accomplishments there have been several key data-sets that have guided the development of retrieval science and the use of polarimetry in understanding the nature of precipitation. One such data set has been collected using the C-Band POLarimetric radar (Keenan et al, 1998), which collected 15 years of observations of break/buildup and monsoon season phenomena when it was sited 23km from Darwin, Australia. This presentation will report on the progress of a collaboration aimed at producing a quality controlled set of polarimetric measurements and microphysical retrievals for this 15-year data set. Techniques such as calibration offset, specific differential phase and attenuation retrieval and comparison with disdrometer measurements (via scattering calculations on collected drop size distributions) will be covered including contrasting several different open source approaches. Seliga, T.A., Bringi, V.N., 1976. Potential Use of Radar Differential Reflectivity Measurements at Orthogonal Polarizations for Measuring Precipitation. J. Appl. Meteor. 15, 69-76. doi:10.1175/1520-0450(1976)015<0069:PUORDR>2.0.CO;2 Hendry, A., McCormick, G.C., 1976. Radar observations of the alignment of precipitation particles by electrostatic fields in thunderstorms. Journal of Geophysical Research 81, 5353-5357. doi:10.1029/JC081i030p05353 Keenan, T., Glasson, K., Cummings, F., Bird, T.S., Keeler, J., Lutz, J., 1998. The BMRC/NCAR C-Band Polarimetric (C-POL) Radar System. Journal of Atmospheric and Oceanic Technology 15, 871-886. doi:10.1175/1520-0426(1998)015<0871:TBNCBP>2.0.CO;2

Spatial gender-age-period-cohort analysis of pancreatic cancer mortality in Spain (1990–2013)

PubMed Central

Etxeberria, Jaione; Goicoa, Tomás; López-Abente, Gonzalo; Riebler, Andrea

2017-01-01

Recently, the interest in studying pancreatic cancer mortality has increased due to its high lethality. In this work a detailed analysis of pancreatic cancer mortality in Spanish provinces was performed using recent data. A set of multivariate spatial gender-age-period-cohort models was considered to look for potential candidates to analyze pancreatic cancer mortality rates. The selected model combines features of APC (age-period-cohort) models with disease mapping approaches. To ensure model identifiability sum-to-zero constraints were applied. A fully Bayesian approach based on integrated nested Laplace approximations (INLA) was considered for model fitting and inference. Sensitivity analyses were also conducted. In general, estimated average rates by age, cohort, and period are higher in males than in females. The higher differences according to age between males and females correspond to the age groups [65, 70), [70, 75), and [75, 80). Regarding the cohort, the greatest difference between men and women is observed for those born between the forties and the sixties. From there on, the younger the birth cohort is, the smaller the difference becomes. Some cohort differences are also identified by regions and age-groups. The spatial pattern indicates a North-South gradient of pancreatic cancer mortality in Spain, the provinces in the North being the ones with the highest effects on mortality during the studied period. Finally, the space-time evolution shows that the space pattern has changed little over time. PMID:28199327

Considerations for Observational Research Using Large Data Sets in Radiation Oncology

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

Jagsi, Reshma, E-mail: rjagsi@med.umich.edu; Bekelman, Justin E.; Chen, Aileen

The radiation oncology community has witnessed growing interest in observational research conducted using large-scale data sources such as registries and claims-based data sets. With the growing emphasis on observational analyses in health care, the radiation oncology community must possess a sophisticated understanding of the methodological considerations of such studies in order to evaluate evidence appropriately to guide practice and policy. Because observational research has unique features that distinguish it from clinical trials and other forms of traditional radiation oncology research, the International Journal of Radiation Oncology, Biology, Physics assembled a panel of experts in health services research to provide a concisemore » and well-referenced review, intended to be informative for the lay reader, as well as for scholars who wish to embark on such research without prior experience. This review begins by discussing the types of research questions relevant to radiation oncology that large-scale databases may help illuminate. It then describes major potential data sources for such endeavors, including information regarding access and insights regarding the strengths and limitations of each. Finally, it provides guidance regarding the analytical challenges that observational studies must confront, along with discussion of the techniques that have been developed to help minimize the impact of certain common analytical issues in observational analysis. Features characterizing a well-designed observational study include clearly defined research questions, careful selection of an appropriate data source, consultation with investigators with relevant methodological expertise, inclusion of sensitivity analyses, caution not to overinterpret small but significant differences, and recognition of limitations when trying to evaluate causality. This review concludes that carefully designed and executed studies using observational data that possess these

Considerations for observational research using large data sets in radiation oncology.

PubMed

Jagsi, Reshma; Bekelman, Justin E; Chen, Aileen; Chen, Ronald C; Hoffman, Karen; Shih, Ya-Chen Tina; Smith, Benjamin D; Yu, James B

2014-09-01

The radiation oncology community has witnessed growing interest in observational research conducted using large-scale data sources such as registries and claims-based data sets. With the growing emphasis on observational analyses in health care, the radiation oncology community must possess a sophisticated understanding of the methodological considerations of such studies in order to evaluate evidence appropriately to guide practice and policy. Because observational research has unique features that distinguish it from clinical trials and other forms of traditional radiation oncology research, the International Journal of Radiation Oncology, Biology, Physics assembled a panel of experts in health services research to provide a concise and well-referenced review, intended to be informative for the lay reader, as well as for scholars who wish to embark on such research without prior experience. This review begins by discussing the types of research questions relevant to radiation oncology that large-scale databases may help illuminate. It then describes major potential data sources for such endeavors, including information regarding access and insights regarding the strengths and limitations of each. Finally, it provides guidance regarding the analytical challenges that observational studies must confront, along with discussion of the techniques that have been developed to help minimize the impact of certain common analytical issues in observational analysis. Features characterizing a well-designed observational study include clearly defined research questions, careful selection of an appropriate data source, consultation with investigators with relevant methodological expertise, inclusion of sensitivity analyses, caution not to overinterpret small but significant differences, and recognition of limitations when trying to evaluate causality. This review concludes that carefully designed and executed studies using observational data that possess these qualities hold

Alarm signs and antibiotic prescription in febrile children in primary care: an observational cohort study

PubMed Central

Elshout, Gijs; van Ierland, Yvette; Bohnen, Arthur M; de Wilde, Marcel; Oostenbrink, Rianne; Moll, Henriëtte A; Berger, Marjolein Y

2013-01-01

Background Although fever in children is often self-limiting, antibiotics are frequently prescribed for febrile illnesses. GPs may consider treating serious infections by prescribing antibiotics. Aim To examine whether alarm signs and/or symptoms for serious infections are related to antibiotic prescription in febrile children in primary care. Design and setting Observational cohort study involving five GP out-of-hours services. Method Clinical information was registered and manually recoded. Children (<16 years) with fever having a face-to-face contact with a GP were included. Children who were already using antibiotics or referred to secondary care were excluded. The relation between alarm signs and/or symptoms for serious infections and antibiotic prescription was tested using multivariate logistic regression. Results Of the 8676 included patients (median age 2.4 years), antibiotics were prescribed in 3167 contacts (36.5%). Patient characteristics and alarm signs and/or symptoms positively related to antibiotic prescription were: increasing age (odds ratio [OR] = 1.03; 95% confidence interval [95% CI] = 1.02 to 1.05), temperature measured by GP (OR = 1.72; 95% CI = 1.59 to 1.86), ill appearance (OR = 3.93; 95% CI = 2.85 to 5.42), being inconsolable (OR = 2.27; 95% CI = 1.58 to 3.22), shortness of breath (OR = 2.58; 95% CI = 1.88 to 3.56), duration of fever (OR = 1.31; 95% CI = 1.26 to 1.35). Negative associations were found for neurological signs (OR = 0.45; 95% CI = 0.27 to 0.76), signs of urinary tract infection (OR = 0.63; 95% CI = 0.49 to 0.82), and vomiting and diarrhoea (OR = 0.65; 95% CI = 0.57 to 0.74). These variables explained 19% of the antibiotic prescriptions. Conclusion Antibiotics are often prescribed for febrile children. These data suggest that treatment of a supposed serious bacterial infection is a consideration of GPs. However, the relatively low explained variation indicates that other considerations are also involved. PMID:23834880

Vaccination coverage and out-of-sequence vaccinations in rural Guinea-Bissau: an observational cohort study

PubMed Central

Hornshøj, Linda; Benn, Christine Stabell; Fernandes, Manuel; Rodrigues, Amabelia; Aaby, Peter; Fisker, Ane Bærent

2012-01-01

Objective The WHO aims for 90% coverage of the Expanded Program on Immunization (EPI), which in Guinea-Bissau included BCG vaccine at birth, three doses of diphtheria−tetanus−pertussis vaccine (DTP) and oral polio vaccine (OPV) at 6, 10 and 14 weeks and measles vaccine (MV) at 9 months when this study was conducted. The WHO assesses coverage by 12 months of age. The sequence of vaccines may have an effect on child mortality, but is not considered in official statistics or assessments of programme performance. We assessed vaccination coverage and frequency of out-of-sequence vaccinations by 12 and 24 months of age. Design Observational cohort study. Setting and participants The Bandim Health Project's (BHP) rural Health and Demographic Surveillance site covers 258 randomly selected villages in all regions of Guinea-Bissau. Villages are visited biannually and vaccination cards inspected to ascertain vaccination status. Between 2003 and 2009 vaccination status by 12 months of age was assessed for 5806 children aged 12–23 months; vaccination status by 24 months of age was assessed for 3792 children aged 24–35 months. Outcome measures Coverage of EPI vaccinations and frequency of out-of-sequence vaccinations. Results Half of 12-month-old children and 65% of 24-month-old children had completed all EPI vaccinations. Many children received vaccines out of sequence: by 12 months of age 54% of BCG-vaccinated children had received DTP with or before BCG and 28% of measles-vaccinated children had received DTP with or after MV. By 24 months of age the proportion of out-of-sequence vaccinations was 58% and 35%, respectively, for BCG and MV. Conclusions In rural Guinea-Bissau vaccination coverage by 12 months of age was low, but continued to increase beyond 12 months of age. More than half of all children received vaccinations out of sequence. This highlights the need to improve vaccination services. PMID:23166127

Changes in Health and Fitness in Firefighter Recruits: An Observational Cohort Study.

PubMed

Cornell, David J; Gnacinski, Stacy L; Meyer, Barbara B; Ebersole, Kyle T

2017-11-01

To observe longitudinal changes in health and fitness among firefighter recruits. Body composition, aerobic capacity, muscular power, muscular strength, and muscular endurance measures were longitudinally collected among 27 male firefighter recruits (mean ± SD, age = 29.9 ± 4.1 yr; height, 179.8 ± 4.6 cm; body mass, 87.2 ± 9.7 kg) at the beginning (W1) and end (W14) of their firefighter training academy, as well as at the end of their probationary period (W38). Repeated-measures multivariate analyses of variance (RM MANOVA) identified significant changes across time among measures of body composition (F10,17 = 30.390, Λ = 0.053, P < 0.001), aerobic capacity (F6,21 = 55.111, Λ = 0.060, P < 0.001), muscular power (F8,17 = 2.785, Λ = 0.433, P = 0.036), muscular strength (F6,20 = 34.908, Λ = 0.087, P < 0.001), and muscular endurance (F4,23 = 25.983, Λ = 0.181, P < 0.001). Follow-up post hoc analyses indicated that all measures, except muscular power, significantly improved from W1 to W14 (P < 0.05). However, significant decrements in many of these measures were also observed from W14 to W38 (P < 0.05). The results of the current study suggest that measures of health and fitness among firefighter recruits significantly improved throughout the firefighter training academy (W1 to W14). However, many of these positive physiological adaptations are lost before these recruits finish their probationary period as active-duty firefighters (W14 to W38). These results highlight the importance of developing exercise programming that is designed for the active-duty firefighter cohort population to maintain the beneficial adaptations in health and fitness previously created during the firefighter training academy.

Regulation of Viable and Optimal Cohorts

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

Aubin, Jean-Pierre, E-mail: aubin.jp@gmail.com

This study deals with the evolution of (scalar) attributes (resources or income in evolutionary demography or economics, position in traffic management, etc.) of a population of “mobiles” (economic agents, vehicles, etc.). The set of mobiles sharing the same attributes is regarded as an instantaneous cohort described by the number of its elements. The union of instantaneous cohorts during a mobile window between two attributes is a cohort. Given a measure defining the number of instantaneous cohorts, the accumulation of the mobile attributes on a evolving mobile window is the measure of the cohort on this temporal mobile window. Imposing accumulationmore » constraints and departure conditions, this study is devoted to the regulation of the evolutions of the attributes which are1.viable in the sense that the accumulations constraints are satisfied at each instant;2.and, among them, optimal, in the sense that both the duration of the temporal mobile window is maximum and that the accumulation on this temporal mobile window is the largest viable one. This value is the “accumulation valuation” function. Viable and optimal evolutions under accumulation constraints are regulated by an “implicit Volterra integro-differential inclusion” built from the accumulation valuation function, solution to an Hamilton–Jacobi–Bellman partial differential equation under constraints which is constructed for this purpose.« less

Fast track pathway reduces sight loss in giant cell arteritis: results of a longitudinal observational cohort study.

PubMed

Patil, P; Williams, M; Maw, W W; Achilleos, K; Elsideeg, S; Dejaco, C; Borg, F; Gupta, S; Dasgupta, B

2015-01-01

To investigate the effectiveness of a fast track pathway (FTP) on sight loss in patients with suspected giant cell arteritis (GCA). A longitudinal observational cohort study was conducted in the secondary care rheumatology department. One hundred and thirty-five newly referred suspected GCA patients seen via the FTP (Jan. 2012-Dec. 2013) were compared to 81 patients seen through the conventional referral and review system (Jan. 2009-Dec. 2011). The FTP resulted in significant reduction in irreversible sight loss from 37.0% (as seen in the historical cohort 2009-2011) to 9.0 % (2012-2013, OR 0.17, p=0.001). Adjustment for clinical and demographic parameters including known risk factors for GCA associated blindness did not significantly change the primary result (OR 0.08, p=0.001). FTP resulted in a reduction of time from symptom onset to diagnosis, particularly by reduction of time from general practitioner's (GP) referral to the rheumatology review (79% of FTP patients were seen within one working day compared to 64.6 % in the conventional pathway, p=0.023). The FTP has seen a reduction in number of GP appointments. There was a significant reduction of permanent sight loss with a fast track GCA pathway. The effect may be due to multiple factors including better GP education and reduction in delayed diagnosis. These results need verification at other sites.

Prediction of liver disease in patients whose liver function tests have been checked in primary care: model development and validation using population-based observational cohorts.

PubMed

McLernon, David J; Donnan, Peter T; Sullivan, Frank M; Roderick, Paul; Rosenberg, William M; Ryder, Steve D; Dillon, John F

2014-06-02

To derive and validate a clinical prediction model to estimate the risk of liver disease diagnosis following liver function tests (LFTs) and to convert the model to a simplified scoring tool for use in primary care. Population-based observational cohort study of patients in Tayside Scotland identified as having their LFTs performed in primary care and followed for 2 years. Biochemistry data were linked to secondary care, prescriptions and mortality data to ascertain baseline characteristics of the derivation cohort. A separate validation cohort was obtained from 19 general practices across the rest of Scotland to externally validate the final model. Primary care, Tayside, Scotland. Derivation cohort: LFT results from 310 511 patients. After exclusions (including: patients under 16 years, patients having initial LFTs measured in secondary care, bilirubin >35 μmol/L, liver complications within 6 weeks and history of a liver condition), the derivation cohort contained 95 977 patients with no clinically apparent liver condition. Validation cohort: after exclusions, this cohort contained 11 653 patients. Diagnosis of a liver condition within 2 years. From the derivation cohort (n=95 977), 481 (0.5%) were diagnosed with a liver disease. The model showed good discrimination (C-statistic=0.78). Given the low prevalence of liver disease, the negative predictive values were high. Positive predictive values were low but rose to 20-30% for high-risk patients. This study successfully developed and validated a clinical prediction model and subsequent scoring tool, the Algorithm for Liver Function Investigations (ALFI), which can predict liver disease risk in patients with no clinically obvious liver disease who had their initial LFTs taken in primary care. ALFI can help general practitioners focus referral on a small subset of patients with higher predicted risk while continuing to address modifiable liver disease risk factors in those at lower risk. Published

Risk factors associated with incident sexually transmitted infections in HIV-positive patients in the Australian HIV Observational Database- a prospective cohort study

PubMed Central

Mulhall, Brian P; Wright, Stephen T; De La Mata, Nicole; Allen, Debbie; Brown, Katherine; Dickson, Bridget; Grotowski, Miriam; Jackson, Eva; Petoumenos, Kathy; Foster, Rosalind; Read, Timothy; Russell, Darren; Smith, David J; Templeton, David J; Fairley, Christopher K; Law, Matthew G

2016-01-01

Background We established a sub-cohort of HIV positive individuals from ten sexual health clinics within the Australian HIV Observational Database (AHOD). The aim of this paper was to assess demographic and other factors that might be associated with an incident sexually transmitted infection (STI). Methods The cohort follow-up was from March 2010 to March 2013, and included patients screened at least once for an STI. We used survival methods to determine time-to first new and confirmed incident STI infection (chlamydia, gonorrhoea, syphilis or genital warts). Factors evaluated included sex, age, mode of HIV exposure, year of AHOD enrolment, hepatitis B or C coinfection, time-updated CD4 cell count, time-updated HIV RNA viral load, and prior STI diagnosis. Results There were 110 first incident STI diagnoses observed over 1015 person-years of follow-up, a crude rate of 10.8 (95% confidence interval [CI]:9.0-13.0) per 100 person-years. Factors independently associated with increased risk of incident STI included younger age (≥50 vs 30-39 years old, adjusted hazards ratio, [aHR]=0.4; 95% CI:0.2-0.8, p<0.0001); prior STI infection, (aHR=2.5; 95% CI: 1.6-3.8, p<0.001); and heterosexual vs men who have sex with men (MSM) as likely exposure (aHR=0.2; 95% CI: 0.1-0.6; p<0.001). Conclusions In this cohort of individuals being treated with anti-retroviral drugs (ARV), who are MSM, 30-39 years old, and with a prior history of STI, are at highest risk of a further STI diagnosis PMID:27019207

Trends in Hip Fracture Rates in Canada: An Age-Period-Cohort Analysis

PubMed Central

Jean, Sonia; O’Donnell, Siobhan; Lagacé, Claudia; Walsh, Peter; Bancej, Christina; Brown, Jacques P.; Morin, Suzanne; Papaioannou, Alexandra; Jaglal, Susan B.; Leslie, William D.

2016-01-01

Age-standardized rates of hip fracture in Canada declined during the period 1985 to 2005. We investigated whether this incidence pattern is explained by period effects, cohort effects, or both. All hospitalizations during the study period with primary diagnosis of hip fracture were identified. Age- and sex-specific hip fracture rates were calculated for nineteen 5-year age groups and four 5-year calendar periods, resulting in 20 birth cohorts. The effect of age, calendar period, and birth cohort on hip fracture rates was assessed using age-period-cohort models as proposed by Clayton and Schiffers. From 1985 to 2005, a total of 570,872 hospitalizations for hip fracture were identified. Age-standardized rates for hip fracture have progressively declined for females and males. The annual linear decrease in rates per 5-year period were 12% for females and 7% for males (both p < 0.0001). Significant birth cohort effects were also observed for both sexes (p < 0.0001). Cohorts born before 1950 had a higher risk of hip fracture, whereas those born after 1954 had a lower risk. After adjusting for age and constant annual linear change (drift term common to both period and cohort effects), we observed a significant nonlinear birth cohort effect for males (p = 0.0126) but not for females (p = 0.9960). In contrast, the nonlinear period effect, after adjustment for age and drift term, was significant for females (p = 0.0373) but not for males (p = 0.2515). For males, we observed no additional nonlinear period effect after adjusting for age and birth cohort, whereas for females, we observed no additional nonlinear birth cohort effect after adjusting for age and period. Although hip fracture rates decreased in both sexes, different factors may explain these changes. In addition to the constant annual linear decrease, nonlinear birth cohort effects were identified for males, and calendar period effects were identified for females as possible explanations. PMID:23426882

Confidence Bounds and Power for the Reliability of Observational Measures on the Quality of a Social Setting

ERIC Educational Resources Information Center

Shin, Yongyun; Raudenbush, Stephen W.

2012-01-01

Social scientists are frequently interested in assessing the qualities of social settings such as classrooms, schools, neighborhoods, or day care centers. The most common procedure requires observers to rate social interactions within these settings on multiple items and then to combine the item responses to obtain a summary measure of setting…

Timing of probiotic milk consumption during pregnancy and effects on the incidence of preeclampsia and preterm delivery: a prospective observational cohort study in Norway

PubMed Central

Nordqvist, Mahsa; Jacobsson, Bo; Brantsæter, Anne-Lise; Myhre, Ronny; Nilsson, Staffan; Sengpiel, Verena

2018-01-01

Objectives To investigate whether the timing of probiotic milk intake before, during early or late pregnancy influences associations with preeclampsia and preterm delivery. Design Population based prospective cohort study. Setting Norway, between 1999 and 2008. Participants 70 149 singleton pregnancies resulting in live-born babies from the Norwegian Mother and Child Cohort Study (no chronic disease, answered questionnaires, no placenta previa/cerclage/serious malformation of fetus, first enrolment pregnancy). Only nulliparous women (n=37 050) were included in the preeclampsia analysis. Both iatrogenic and spontaneous preterm delivery (between gestational weeks 22+0 and 36+6) with spontaneous term controls (between gestational weeks 39+0 and 40+6) were included in the preterm delivery analysis resulting in 34 458 cases. Main outcome measures Adjusted OR for preeclampsia and preterm delivery according to consumption of probiotic milk at three different time periods (before pregnancy, during early and late pregnancy). Results Probiotic milk intake in late pregnancy (but not before or in early pregnancy) was significantly associated with lower preeclampsia risk (adjusted OR: 0.80 (95% CI 0.68 to 0.94) p-value: 0.007). Probiotic intake during early (but not before or during late pregnancy) was significantly associated with lower risk of preterm delivery (adjusted OR: 0.79 (0.64 to 0.97) p-value: 0.03). Conclusions In this observational study, we found an association between timing of probiotic milk consumption during pregnancy and the incidence of the adverse pregnancy outcomes preeclampsia and preterm delivery. If future randomised controlled trials could establish a causal association between probiotics consumption and reduced risk of preeclampsia and preterm delivery, recommending probiotics would be a promising public health measure to reduce these adverse pregnancy outcomes. PMID:29362253

Social Origin and Graduation Age: A Cohort Comparison of Danish University Students

ERIC Educational Resources Information Center

Klausen, Trond Beldo

2016-01-01

This paper investigates whether social origin has an impact on graduation age among university students. A large number of social background factors are applied on a large data set of 4 successive cohorts of Danish university graduates born 1960-1975. These are cohorts for whom university attendance increased steeply. Contrary to recent findings…

The effects of climate downscaling technique and observational data set on modeled ecological responses

Treesearch

Afshin Pourmokhtarian; Charles T. Driscoll; John L. Campbell; Katharine Hayhoe; Anne M. K. Stoner

2016-01-01

Assessments of future climate change impacts on ecosystems typically rely on multiple climate model projections, but often utilize only one downscaling approach trained on one set of observations. Here, we explore the extent to which modeled biogeochemical responses to changing climate are affected by the selection of the climate downscaling method and training...

Investing in Prospective Cohorts for Etiologic Study of Occupational Exposures

PubMed Central

Blair, A.; Hines, C.J.; Thomas, K.W.; Alavanja, M.C.R.; Beane Freeman, L.E.; Hoppin, J.A.; Kamel, F.; Lynch, C.F.; Lubin, J.H.; Silverman, D.T.; Whelan, E.; Zahm, S. H.; Sandler, D. P.

2015-01-01

Prospective cohorts have played a major role in understanding the contribution of diet, physical activity, medical conditions, and genes to the development of many diseases, but have not been widely used for occupational exposures. Studies in agriculture are an exception. We draw upon our experience using this design to study agricultural workers to identify conditions that might foster use of prospective cohorts to study other occupational settings. Prospective cohort studies are perceived by many as the strongest epidemiologic design. It allows updating of information on exposure and other factors, collection of biologic samples before disease diagnosis for biomarker studies, assessment of effect modification by genes, lifestyle, and other occupational exposures, and evaluation of a wide range of health outcomes. Increased use of prospective cohorts would be beneficial in identifying hazardous exposures in the workplace. Occupational epidemiologists should seek opportunities to initiate prospective cohorts to investigate high priority, occupational exposures. PMID:25603935

Particulate air pollution and mortality in a cohort of Chinese men.

PubMed

Zhou, Maigeng; Liu, Yunning; Wang, Lijun; Kuang, Xingya; Xu, Xiaohui; Kan, Haidong

2014-03-01

Few prior cohort studies exist in developing countries examining the association of ambient particulate matter (PM) with mortality. We examined the association of particulate air pollution with mortality in a prospective cohort study of 71,431 middle-aged Chinese men. Baseline data were obtained during 1990-1991. The follow-up evaluation was completed in January, 2006. Annual average PM exposure between 1990 and 2005, including TSP and PM10, were estimated by linking fixed-site monitoring data with residential communities. We found significant associations between PM10 and mortality from cardiopulmonary diseases; each 10 μg/m(3) PM10 was associated with a 1.6% (95%CI: 0.7%, 2.6%), 1.8% (95%CI: 0.8%, 2.9%) and 1.7% (95%CI: 0.3%, 3.2%) increased risk of total, cardiovascular and respiratory mortality, respectively. For TSP, we observed significant associations only for cardiovascular morality. These data contribute to the scientific literature on long-term effects of particulate air pollution for high exposure settings typical in developing countries. Copyright © 2013 Elsevier Ltd. All rights reserved.

Gender-Specific Combination HIV Prevention for Youth in High-Burden Settings: The MP3 Youth Observational Pilot Study Protocol

PubMed Central

Agot, Kawango

2017-01-01

Background Nearly three decades into the epidemic, sub-Saharan Africa (SSA) remains the region most heavily affected by human immunodeficiency virus (HIV), with nearly 70% of the 34 million people living with HIV globally residing in the region. In SSA, female and male youth (15 to 24 years) are at a disproportionately high risk of HIV infection compared to adults. As such, there is a need to target HIV prevention strategies to youth and to tailor them to a gender-specific context. This protocol describes the process for the multi-staged approach in the design of the MP3 Youth pilot study, a gender-specific, combination, HIV prevention intervention for youth in Kenya. Objective The objective of this multi-method protocol is to outline a rigorous and replicable methodology for a gender-specific combination HIV prevention pilot study for youth in high-burden settings, illustrating the triangulated methods undertaken to ensure that age, sex, and context are integral in the design of the intervention. Methods The mixed-methods, cross-sectional, longitudinal cohort pilot study protocol was developed by first conducting a systematic review of the literature, which shaped focus group discussions around prevention package and delivery options, and that also informed age- and sex- stratified mathematical modeling. The review, qualitative data, and mathematical modeling created a triangulated evidence base of interventions to be included in the pilot study protocol. To design the pilot study protocol, we convened an expert panel to select HIV prevention interventions effective for youth in SSA, which will be offered in a mobile health setting. The goal of the pilot study implementation and evaluation is to apply lessons learned to more effective HIV prevention evidence and programming. Results The combination HIV prevention package in this protocol includes (1) offering HIV testing and counseling for all youth; (2) voluntary medical circumcision and condoms for males; (3

The effects of climate downscaling technique and observational data set on modeled ecological responses.

PubMed

Pourmokhtarian, Afshin; Driscoll, Charles T; Campbell, John L; Hayhoe, Katharine; Stoner, Anne M K

2016-07-01

Assessments of future climate change impacts on ecosystems typically rely on multiple climate model projections, but often utilize only one downscaling approach trained on one set of observations. Here, we explore the extent to which modeled biogeochemical responses to changing climate are affected by the selection of the climate downscaling method and training observations used at the montane landscape of the Hubbard Brook Experimental Forest, New Hampshire, USA. We evaluated three downscaling methods: the delta method (or the change factor method), monthly quantile mapping (Bias Correction-Spatial Disaggregation, or BCSD), and daily quantile regression (Asynchronous Regional Regression Model, or ARRM). Additionally, we trained outputs from four atmosphere-ocean general circulation models (AOGCMs) (CCSM3, HadCM3, PCM, and GFDL-CM2.1) driven by higher (A1fi) and lower (B1) future emissions scenarios on two sets of observations (1/8º resolution grid vs. individual weather station) to generate the high-resolution climate input for the forest biogeochemical model PnET-BGC (eight ensembles of six runs).The choice of downscaling approach and spatial resolution of the observations used to train the downscaling model impacted modeled soil moisture and streamflow, which in turn affected forest growth, net N mineralization, net soil nitrification, and stream chemistry. All three downscaling methods were highly sensitive to the observations used, resulting in projections that were significantly different between station-based and grid-based observations. The choice of downscaling method also slightly affected the results, however not as much as the choice of observations. Using spatially smoothed gridded observations and/or methods that do not resolve sub-monthly shifts in the distribution of temperature and/or precipitation can produce biased results in model applications run at greater temporal and/or spatial resolutions. These results underscore the importance of

The rate of sputum smear-positive tuberculosis after treatment default in a high-burden setting: a retrospective cohort study.

PubMed

Marx, Florian M; Dunbar, Rory; Enarson, Donald A; Beyers, Nulda

2012-01-01

High rates of recurrent tuberculosis after successful treatment have been reported from different high burden settings in Sub-Saharan Africa. However, little is known about the rate of smear-positive tuberculosis after treatment default. In particular, it is not known whether or not treatment defaulters continue to be or become again smear-positive and thus pose a potential for transmission of infection to others. To investigate, in a high tuberculosis burden setting, the rate of re-treatment for smear-positive tuberculosis among cases defaulting from standardized treatment compared to successfully treated cases. Retrospective cohort study among smear-positive tuberculosis cases treated between 1996 and 2008 in two urban communities in Cape Town, South Africa. Episodes of re-treatment for smear-positive tuberculosis were ascertained via probabilistic record linkage. Survival analysis and Poisson regression were used to compare the rate of smear-positive tuberculosis after treatment default to that after successful treatment. A total of 2,136 smear-positive tuberculosis cases were included in the study. After treatment default, the rate of re-treatment for smear-positive tuberculosis was 6.86 (95% confidence interval [CI]: 5.59-8.41) per 100 person-years compared to 2.09 (95% CI: 1.81-2.41) after cure (adjusted Hazard Ratio [aHR]: 3.97; 95% CI: 3.00-5.26). Among defaulters, the rate was inversely associated with treatment duration and sputum conversion prior to defaulting. Smear grade at start of the index treatment episode (Smear3+: aHR 1.61; 95%CI 1.11-2.33) was independently associated with smear-positive tuberculosis re-treatment, regardless of treatment outcome. In this high-burden setting, there is a high rate of subsequent smear-positive tuberculosis after treatment default. Treatment defaulters are therefore likely to contribute to the pool of infectious source cases in the community. Our findings underscore the importance of preventing treatment default, as

Feasibility of reusing time-matched controls in an overlapping cohort.

PubMed

Delcoigne, Bénédicte; Hagenbuch, Niels; Schelin, Maria Ec; Salim, Agus; Lindström, Linda S; Bergh, Jonas; Czene, Kamila; Reilly, Marie

2018-06-01

The methods developed for secondary analysis of nested case-control data have been illustrated only in simplified settings in a common cohort and have not found their way into biostatistical practice. This paper demonstrates the feasibility of reusing prior nested case-control data in a realistic setting where a new outcome is available in an overlapping cohort where no new controls were gathered and where all data have been anonymised. Using basic information about the background cohort and sampling criteria, the new cases and prior data are "aligned" to identify the common underlying study base. With this study base, a Kaplan-Meier table of the prior outcome extracts the risk sets required to calculate the weights to assign to the controls to remove the sampling bias. A weighted Cox regression, implemented in standard statistical software, provides unbiased hazard ratios. Using the method to compare cases of contralateral breast cancer to available controls from a prior study of metastases, we identified a multifocal tumor as a risk factor that has not been reported previously. We examine the sensitivity of the method to an imperfect weighting scheme and discuss its merits and pitfalls to provide guidance for its use in medical research studies.

Costs of adult vaccination in medical settings and pharmacies: an observational study.

PubMed

Singhal, Puneet K; Zhang, Dongmu

2014-09-01

Community pharmacies are a convenient setting for vaccinating adults against infectious diseases in the United States. Whether the costs paid for vaccination in pharmacies differ from those in medical settings is unclear. To examine whether the direct medical costs paid for adult vaccination differ by vaccination setting. This was an observational retrospective study using 2010 MarketScan Commercial Claims and Encounters and Medicare Supplemental and Coordination of Benefits databases. Adults receiving herpes zoster or shingles vaccine, pneumococcal vaccine 23-valent, or influenza vaccines were identified using Current Procedural Terminology codes and National Drug Code numbers from medical and pharmacy claims files, respectively, between January 1 and December 31, 2010, in 1 of the following 3 settings: physician offices; other medical settings (e.g., inpatient/outpatient hospitals, emergency rooms); and pharmacies. Patients were adults aged ≥60 years on the date of zoster vaccination and aged ≥19 years on the date of pneumococcal or influenza vaccinations. The final study samples meeting inclusion/exclusion criteria were 54,042 for zoster vaccine, 154,994 for pneumococcal vaccine, and 1,657,264 for influenza vaccine. The vaccination costs included the health plan and enrollee paid amounts for the product; vaccine administration; dispensing fee; and, where applicable, the visit. The mean (SD) vaccination costs paid per vaccine administration were estimated by vaccine and type of setting, overall, and by geographic region and type of health plan. The costs paid for the same vaccine across vaccination settings were compared using analysis of variance with post hoc tests (Tukey). Of those receiving zoster, pneumococcal, and influenza vaccines, 25%, 1%, and 7%, respectively, received the vaccines at a pharmacy. Compared with other U.S. regions, pharmacy-based vaccination for these 3 vaccines was generally more frequent in the West and the South. Overall, the mean

Economic crisis and smoking behaviour: prospective cohort study in Iceland

PubMed Central

McClure, Christopher Bruce; Valdimarsdóttir, Unnur A; Hauksdóttir, Arna; Kawachi, Ichiro

2012-01-01

Objective To examine the associations between the 2008 economic collapse in Iceland and smoking behaviour at the national and individual levels. Design A population-based, prospective cohort study based on a mail survey (Health and Wellbeing in Iceland) assessed in 2007 and 2009. Setting National mail survey. Participants Representative cohort (n=3755) of Icelandic adults. Main outcome measure Smoking status. Results A significant reduction in the prevalence of smoking was observed from 2007 (pre-economic collapse) to 2009 (postcollapse) in both males (17.4–14.8%; p 0.01) and females (20.0–17.5%; p 0.01) in the cohort (n=3755). At the individual level of analysis, male former smokers experiencing a reduction in income during the same period were less likely to relapse (OR 0.37; 95% CI 0.16 to 0.85). Female smokers were less likely to quit over time compared to males (OR 0.65; 95% CI 0.45 to 0.93). Among male former smokers who experienced an increase in income between 2007 and 2009, we observed an elevated risk of smoking relapse (OR 4.02; 95% CI 1.15 to 14.00). Conclusions The national prevalence of smoking in Iceland declined following the 2008 economic crisis. This could be due to the procyclical relationship between macro-economic conditions and smoking behaviour (ie, hard times lead to less smoking because of lower affordability), or it may simply reflect a continuation of trends already in place prior to the crisis. In individual-level analysis, we find that former smokers who experienced a decline in income were less likely to relapse; and conversely, an increase in income raises the risk. However, caution is warranted since these findings are based on small numbers. PMID:23048059

Baseline Lower Urinary Tract Symptoms in Patients Enrolled in LURN: A Prospective, Observational Cohort Study.

PubMed

Cameron, Anne P; Lewicky-Gaupp, Christina; Smith, Abigail R; Helfand, Brian T; Gore, John L; Clemens, J Quentin; Yang, Claire C; Siddiqui, Nazema Y; Lai, H Henry; Griffith, James W; Andreev, Victor P; Liu, Gang; Weinfurt, Kevin; Amundsen, Cindy L; Bradley, Catherine S; Kusek, John W; Kirkali, Ziya

2018-04-01

We described and compared the frequency and type of lower urinary tract symptoms reported by men and women at the time that they were recruited from urology and urogynecology clinics into the Symptoms of Lower Urinary Tract Dysfunction Research Network multicenter, prospective, observational cohort study. At 6 research sites treatment seeking men and women were enrolled who reported any lower urinary tract symptoms at a frequency more than rarely during the last month on the LUTS (Lower Urinary Tract Symptoms) Tool. At baseline the study participants underwent a standardized clinical evaluation and completed validated questionnaires. Urological tests were performed, including pelvic/rectal examination, post-void residual urine measurement and urinalysis. A total of 545 women and 519 men were enrolled in the study. Mean ± SD age was 58.8 ± 14.1 years. At baseline nocturia, frequency and a sensation of incomplete emptying were similar in men and women but men experienced more voiding symptoms (90% vs 85%, p = 0.007) and women reported more urgency (85% vs 66%, p <0.001). Women also reported more of any type of urinary incontinence than men (82% vs 51% p <0.001), which was mixed incontinence in 57%. Only 1% of men reported stress incontinence but they had other urinary incontinence, including post-void dribbling in 44% and urgency incontinence in 46%. Older participants had higher odds of reporting symptoms of nocturia and urgency. In this large, treatment seeking cohort of men and women lower urinary tract symptoms varied widely by gender and age. Men reported more voiding symptoms and nonstress or urgency urinary incontinence while women reported more incontinence overall and urgency. Older participants had greater odds of urgency and nocturia. Copyright © 2018 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Breastfeeding and adolescent blood pressure: evidence from Hong Kong's "Children of 1997" Birth Cohort.

PubMed

Kwok, Man Ki; Leung, Gabriel M; Schooling, C Mary

2013-09-15

Observationally, breastfeeding is associated with lower blood pressure in Western developed settings, whereas little association exists in developing settings. However, postnatal characteristics (e.g., breast milk substitutes, infection rates, underweight, and pubertal timing) differ between these settings. We examined the association of breastfeeding with blood pressure at ∼13 years, using multivariable linear regression, in 5,247 term births in 1997 from a population-representative Hong Kong Chinese birth cohort where socioeconomic patterning of breastfeeding differs from that of Western and developing settings but standard of living, social infrastructure, and postnatal characteristics are similar to those of Western settings. Higher education is associated with short-term breastfeeding but recent migration with longer-term breastfeeding. Compared with never breastfeeding, exclusive breastfeeding for ≥3 months was not associated with blood pressure (systolic mean difference = 0.82 mm Hg, 95% confidence interval (CI): -0.46, 2.11 and diastolic mean difference = 0.49 mm Hg, 95% CI: -0.22, 1.21), nor was partial breastfeeding for any length of time or exclusive breastfeeding for <3 months (systolic mean difference = 0.01 mm Hg, 95% CI: -0.64, 0.66 and diastolic mean difference = 0.16 mm Hg, 95% CI: -0.20, 0.52), adjusted for socioeconomic position and infant characteristics. Lack of association in a non-Western developed setting further suggests that observations concerning breastfeeding and blood pressure vary with setting, thereby casting doubt on causality.

Low-Frequency Amplitudes Observed in a Set of the Strongest Recorded Ground Motions (Invited)

NASA Astrophysics Data System (ADS)

Anderson, J. G.; Koketsu, K.; Miyake, H.

2010-12-01

Anderson (2010) compiled a set of “exceptional” ground motion characterized by peak acceleration that exceeds 500 gal on at least one component or peak velocity that exceeds 50 cm/s on at least one component. With the addition of more recent data, there are now over 280 openly available records that meet these criteria. These data are examined to find to the empirical upper bound of observed pseudo-acceleration (PSA) response spectra and smoothed Fourier amplitude spectra. Statistics of amplitudes of PSA and of low-pass filtered acceleration and velocity have also been determined. Amplitudes recorded at the Kawaguchi-cho station (40 km) at 5-6 second period from the 1964 Niigata earthquake (Mw=8.3) are within ~20% of the current empirical limit of ground motions observed from all earthquakes in the data set including those from the near field. An even more impressive example is that amplitudes recorded at the SCT station (~300 km from the fault) with period of about 2 seconds, during the 1985 Michoacan, Mexico, earthquake (Mw=8.0), are about the same as the current empirical limit of ground motions observed from near field records. These examples support the idea that the hazard caused by long-period ground motions, amplified by basins and site conditions, is not sufficiently appreciated. Reference: Anderson, J. G. (2010), Bull. Seism. Soc. Am. 100, 1-36.

Biological sex and social setting affects pain intensity and observational coding of other people's pain behaviors.

PubMed

Vigil, Jacob M; Coulombe, Patrick

2011-09-01

This experiment examines the impact of biological sex and audience composition on laboratory-induced ischemic pain intensity and observational coding of other people's pain behaviors. Situational context was manipulated by varying the sex and number of audience stimuli in the laboratory setting during the pain task and during observational evaluations of other people's pain suffering. The analyses revealed sex differences in felt pain intensity and observable pain behaviors, with male subjects reporting lower pain intensity and evidencing fewer pain behaviors than female subjects on average. Follow-up analyses revealed that, after controlling for social anxiety, audience composition was linked to felt pain intensity, and this relation was moderated by participant sex and audience sex, such that only male subjects showed decreased pain intensity with increasing number of female audience members. Sex differences were also found in the rating of other people's pain behaviors, with male observers rating the pain of others lower than female observers. Composition of the audience influenced observers' pain ratings such that the presence of more male subjects in the audience correlated with lower observer ratings, whereas the presence of more female subjects correlated with higher observer ratings. This is the first study to show that the sex and the composition of the social context in which pain is experienced affects the intensity of felt pain and the evaluation of other people's pain suffering. Implications of the findings for measuring and interpreting pain suffering in male and female patients by male and female treatment providers in health care settings are discussed. Published by Elsevier B.V.

European Prevention of Alzheimer's Dementia Registry: Recruitment and prescreening approach for a longitudinal cohort and prevention trials.

PubMed

Vermunt, Lisa; Veal, Colin D; Ter Meulen, Lea; Chrysostomou, Charalambos; van der Flier, Wiesje; Frisoni, Giovanni B; Guessous, Idris; Kivipelto, Miia; Marizzoni, Moira; Martinez-Lage, Pablo; Molinuevo, José Luis; Porteous, David; Ritchie, Karen; Scheltens, Philip; Ousset, Pierre-Jean; Ritchie, Craig W; Luscan, Gerald; Brookes, Anthony J; Visser, Pieter Jelle

2018-06-01

It is a challenge to find participants for Alzheimer's disease (AD) prevention trials within a short period of time. The European Prevention of Alzheimer's Dementia Registry (EPAD) aims to facilitate recruitment by preselecting subjects from ongoing cohort studies. This article introduces this novel approach. A virtual registry, with access to risk factors and biomarkers for AD through minimal data sets of ongoing cohort studies, was set up. To date, ten cohorts have been included in the EPAD. Around 2500 participants have been selected, using variables associated with the risk for AD. Of these, 15% were already recruited in the EPAD longitudinal cohort study, which serves as a trial readiness cohort. This study demonstrates that a virtual registry can be used for the preselection of participants for AD studies. Copyright © 2018 the Alzheimer's Association. Published by Elsevier Inc. All rights reserved.

The Observer Effect and Its Impact on Staff Behavior in an Acquired Brain Injury Neurobehavioral Treatment Setting

ERIC Educational Resources Information Center

Guercio, John M.; Dixon, Mark R.

2011-01-01

Staff in three neurobehavioral residential settings (5 in each residence for a total of 15 staff) were trained on specific positive interaction behaviors in a multiple baseline design. Staff in each of the residences were provided with recommended behaviors for interacting with residents through an observational procedure where they observed and…

Body size dynamics in young adults: 8-year follow up of cohorts in Brazil and Thailand.

PubMed

Yiengprugsawan, V; Horta, B L; Motta, J V S; Gigante, D; Seubsman, S-A; Sleigh, A

2016-07-18

Increase in body size has appeared as an epidemic in Western countries and is now rapidly emerging in low- and middle-income countries, contributing to the rise in non-communicable diseases worldwide. Brazil and Thailand have gone through similar economic and health transitions, and this unique comparative study investigates changes in body size (body mass index) in relation to socioeconomic status in two cohorts of similar age followed from 2004/2005 to 2012/2013. At 20-24 years of age, Pelotas cohort members had a much higher prevalence of overweight and obesity (20.7 and 8.6%) than the Thai cohort (6.0 and 1.7%); these proportions rose to 34.6% and 22.9% vs 15.8% and 5.1%, respectively, in their early 30s. An association between a higher socioeconomic status and increase in overweight and obesity was observed among males; but an inverse pattern was noted for females in both cohorts and remained statistically significant after 8 years of follow up. Our comparative longitudinal analyses highlight the relationship between two middle-income settings facing rapid increases in body size (2-3 fold increase in the rate of overweight and obesity). Long-term follow up and a lifecourse approach for effective prevention of obesity will minimize adverse health burdens in later life.

Cohort profile for the Nurture Observational Study examining associations of multiple caregivers on infant growth in the Southeastern USA.

PubMed

Benjamin Neelon, Sara E; Østbye, Truls; Bennett, Gary G; Kravitz, Richard M; Clancy, Shayna M; Stroo, Marissa; Iversen, Edwin; Hoyo, Cathrine

2017-02-08

Childcare has been associated with obesity in children in cross-sectional and longitudinal studies, although some observed no association. Few studies have focused on care during infancy, a period when children may be especially vulnerable. The Nurture Study is an observational birth cohort designed to assess longitudinal associations of childcare and the presence of multiple caregivers on infant adiposity and weight trajectories throughout the first year of life. We examine as potential mediators feeding, physical activity, sleep and stress. We completed recruitment in 2015. Of the 860 women who enrolled during pregnancy, 799 delivered a single live infant who met our inclusion criteria. Of those, 666 mothers (77.4%) agreed to participate in the study for themselves and their infants. Among the 666 women in the study, 472 (71%) identified as black, 127 (19%) as white, 7 (1%) as Asian or Asian American, 6 (1%) as Native American and 49 (7%) as other race or more than one race; 43 (7%) identified as Hispanic/Latina. Just under half (48%) had a high school diploma or less, 61% had household incomes <$20 000/year and 59% were married or living with a partner. The mean (SD) infant gestational age was 41.28 weeks (2.29) and birth weight for gestational age z-score was -0.31 (0.93). Just under half (49%) of infants were females, 69% received some human milk and 40% were exclusively breast fed at hospital discharge. Data collection began in 2013, is currently underway, and is scheduled to conclude in late 2016. Results will help assess the magnitude of associations between childcare in infancy and subsequent obesity. Findings will also inform intervention and policy efforts to improve childcare environments and help prevent obesity in settings where many infants spend time. Clinicaltrials.gov, NCT01788644. 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/.

Cohort profile for the Nurture Observational Study examining associations of multiple caregivers on infant growth in the Southeastern USA

PubMed Central

Benjamin Neelon, Sara E; Østbye, Truls; Bennett, Gary G; Kravitz, Richard M; Clancy, Shayna M; Stroo, Marissa; Iversen, Edwin; Hoyo, Cathrine

2017-01-01

Purpose Childcare has been associated with obesity in children in cross-sectional and longitudinal studies, although some observed no association. Few studies have focused on care during infancy, a period when children may be especially vulnerable. Participants The Nurture Study is an observational birth cohort designed to assess longitudinal associations of childcare and the presence of multiple caregivers on infant adiposity and weight trajectories throughout the first year of life. We examine as potential mediators feeding, physical activity, sleep and stress. We completed recruitment in 2015. Of the 860 women who enrolled during pregnancy, 799 delivered a single live infant who met our inclusion criteria. Of those, 666 mothers (77.4%) agreed to participate in the study for themselves and their infants. Findings to date Among the 666 women in the study, 472 (71%) identified as black, 127 (19%) as white, 7 (1%) as Asian or Asian American, 6 (1%) as Native American and 49 (7%) as other race or more than one race; 43 (7%) identified as Hispanic/Latina. Just under half (48%) had a high school diploma or less, 61% had household incomes <$20 000/year and 59% were married or living with a partner. The mean (SD) infant gestational age was 41.28 weeks (2.29) and birth weight for gestational age z-score was −0.31 (0.93). Just under half (49%) of infants were females, 69% received some human milk and 40% were exclusively breast fed at hospital discharge. Data collection began in 2013, is currently underway, and is scheduled to conclude in late 2016. Future plans Results will help assess the magnitude of associations between childcare in infancy and subsequent obesity. Findings will also inform intervention and policy efforts to improve childcare environments and help prevent obesity in settings where many infants spend time. Trial registration number Clinicaltrials.gov, NCT01788644. PMID:28179416

Sleep Disordered Breathing in Four Resource-Limited Settings in Peru: Prevalence, Risk Factors, and Association with Chronic Diseases

PubMed Central

Schwartz, Noah G.; Rattner, Adi; Schwartz, Alan R.; Mokhlesi, Babak; Gilman, Robert H.; Bernabe-Ortiz, Antonio; Miranda, J. Jaime; Checkley, William

2015-01-01

Study Objectives: Sleep disordered breathing (SDB) is a highly prevalent condition in high-income countries, with major consequences for cardiopulmonary health, public safety, healthcare utilization, and mortality. However, its prevalence and effect in low- and middle-income countries are less well known. We sought to determine the prevalence, risk factors, and comorbidities of SDB symptoms in four resource-limited settings. Design: Cross-sectional analysis of the CRONICAS Cohort, a population-based age- and sex-stratified sample. Setting: Four resource-limited settings in Peru varying in altitude, urbanization, and air pollution. Participants: There were 2,682 adults aged 35 to 92 y. Measurements and Results: Self-reported SDB symptoms (habitual snoring, observed apneas, Epworth Sleepiness Scale), sociodemographics, medical history, anthropometrics, spirometry, blood biomarkers were reported. We found a high prevalence of habitual snoring (30.2%, 95% confidence interval [CI] 28.5–32.0%), observed apneas (20.9%, 95% CI 19.4–22.5%) and excessive daytime sleepiness (18.6%, 95% CI 17.1–20.1%). SDB symptoms varied across sites; prevalence and adjusted odds for habitual snoring were greatest at sea level, whereas those for observed apneas were greatest at high altitude. In multivariable analysis, habitual snoring was associated with older age, male sex, body mass index (BMI), and higher socioeconomic status; observed apneas were associated with BMI; and excessive daytime sleepiness was associated with older age, female sex, and medium socioeconomic status. Adjusted odds of cardiovascular disease, depression, and hypertension and total chronic disease burden increased progressively with the number of SDB symptoms. A threefold increase in the odds of having an additional chronic comorbid disease (adjusted odds ratio 3.57, 95% CI 2.18–5.84) was observed in those with all three versus no SDB symptoms. Conclusions: Sleep disordered breathing symptoms were highly

Achieving consensus on minimum data items (including core outcome domains) for a longitudinal observational cohort study in rheumatoid arthritis.

PubMed

Nikiphorou, Elena; Mackie, Sarah L; Kirwan, John; Boers, Martin; Isaacs, John; Morgan, Ann W; Young, Adam

2017-04-01

To obtain consensus on the minimum data items for an observational cohort study in RA in the UK and to make available the process for similar studies and other rheumatic conditions. Individuals with a diverse range of expertise and backgrounds were invited to participate in a process of proposing a minimum core dataset (MCD) for research studies, commissioned by Arthritis Research UK as part of the larger INBANK project. The group included patients and representatives from clinical and academic rheumatology, outcomes science, stratified medicine, health economics, and national professional and academic bodies/committees. A process was devised based on OMERACT principles for reviewing aims/objectives, defining the scope, identifying the important research questions and selecting key domains. Following the initial multistakeholder meeting, subsequent teleconferences and email communications: consensus was obtained on the most important and relevant research questions; agreement on how the OMERACT Core Areas (life impact, pathophysiological manifestations, resource use and death) could form the basis of a MCD; and consensus on 22 items for inclusion into a MCD. Workshops were undertaken for two essential items that required further exploration: work/social participation and co-morbidity. Reaching a consensus for the proposed minimal data items for long-term observational cohort studies of RA in the UK posed novel challenges and opportunities, and was largely successful. Further work is needed for selecting instruments for two important items and for achieving compatibility with other UK national initiatives, and more widely across Europe. © The Author 2016. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Association of postoperative pulmonary complications with delayed mobilisation following major abdominal surgery: an observational cohort study.

PubMed

Haines, K J; Skinner, E H; Berney, S

2013-06-01

Previous Australian studies reported that postoperative pulmonary complications affect 13% of patients undergoing upper abdominal laparotomy. This study measured the incidence of postoperative pulmonary complications, risk factors for the diagnosis of postoperative pulmonary complications and barriers to physiotherapy mobilisation in a cohort of patients undergoing high-risk abdominal surgery. Prospective, observational cohort study. Two surgical wards in a tertiary Australian hospital. Seventy-two patients undergoing high-risk abdominal surgery (participants in a larger trial evaluating a novel model of medical co-management). Incidence of, and risk factors for, postoperative pulmonary complications, barriers to mobilisation and length of stay. The incidence of postoperative pulmonary complications was 39%. Incision type and time to mobilise away from the bed were independently associated with a diagnosis of postoperative pulmonary complications. Patients were 3.0 (95% confidence interval 1.2 to 8.0) times more likely to develop a postoperative pulmonary complication for each postoperative day they did not mobilise away from the bed. Fifty-two percent of patients had a barrier to mobilisation away from the bed on the first postoperative day, with the most common barrier being hypotension, although cessation criteria were not defined objectively by physiotherapists. Development of a postoperative pulmonary complication increased median hospital length of stay (16 vs 13 days; P=0.046). This study demonstrated an association between delayed postoperative mobilisation and postoperative pulmonary complications. Randomised controlled trials are required to test the role of early mobilisation in preventing postoperative pulmonary complications in patients undergoing high-risk upper abdominal surgery. Copyright © 2012 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.

Possibilities and considerations when merging dietary data from the world's two largest pregnancy cohorts: the Danish National Birth Cohort and the Norwegian Mother and Child Cohort Study.

PubMed

Olsen, Sjurdur F; Birgisdottir, Bryndis Eva; Halldorsson, Thorhallur I; Brantsaeter, Anne Lise; Haugen, Margaretha; Torjusen, Hanne; Petersen, Sesilje B; Strøm, Marin; Meltzer, Helle Margrete

2014-11-01

To elucidate the research possibilities when merging data on maternal diet from the Danish National Birth Cohort (DNBC) and the Norwegian Mother and Child Cohort Study (MoBa), through comparison of (i) the methodology used for dietary assessment and (ii) the estimated intake of selected food groups in the two cohorts. Qualitative and quantitative comparison of the two dietary databases. Two national prospective pregnancy cohorts. Denmark, Norway. Comparison of food intake using food frequency questionnaires (FFQs). The FFQs had overlapping time windows and a majority of the questions in the two FFQs were comparable. Calculation principles shared similar features, including the software used and use of global questions to calibrate intakes of different food groups. A total of 63 food groups were defined that could be compared across the two cohorts; these were further aggregated down to 31 broader groups. A comparison of food intakes (grams/d) showed 39, 74 and 141% lower daily intakes of fish, potatoes and rice, respectively, in DNBC vs. MoBa and 39, 54 and 65% higher daily intakes of milk, butter and potatoes in DNBC vs. MoBa. For most other food groups, differences in consumption data were below 20%. The two FFQs are to a large extent compatible and substantial differences in dietary habits were observed between the two cohorts. This may strengthen studies using pooled analysis to examine diet-disease relations. This is a conclusion of great importance given the colossal and costly task involved to establish each of these two cohorts. © 2014 Nordic Federation of Societies of Obstetrics and Gynecology.

Two industrial cohorts: baseline characteristics and factors associated with obesity.

PubMed

Ott, Ulrike; Stanford, Joseph B; Thiese, Matthew S; Murtaugh, Maureen A; Greenwood, Jessica L J; Gren, Lisa H; Garg, Arun; Hegmann, Kurt T

2015-05-01

To describe demographic and health characteristics, and factors associated with obesity among production workers. This cross-sectional study analyzed baseline data from two occupational cohorts. Regression modeling was used to assess associations between worker characteristics and obesity. A total of 1974 subjects were included in these analyses. The mean body mass index was 29.5 kg/m (SD = 6.5). Having smoked in the past and currently smoking decreased the odds of being obese in the WISTAH Distal Upper Extremity cohort, whereas those feeling depressed had increased odds of being obese. Being a Pacific Islander/Native Hawaiian and married increased the odds of obesity in the BackWorks Low Back Pain cohort. Factors associated with obesity differed substantially between the two cohorts. Recognizing factors associated with obesity in specific work settings may provide opportunities for optimizing preventive workplace interventions.

Initial validation of the prekindergarten Classroom Observation Tool and goal setting system for data-based coaching.

PubMed

Crawford, April D; Zucker, Tricia A; Williams, Jeffrey M; Bhavsar, Vibhuti; Landry, Susan H

2013-12-01

Although coaching is a popular approach for enhancing the quality of Tier 1 instruction, limited research has addressed observational measures specifically designed to focus coaching on evidence-based practices. This study explains the development of the prekindergarten (pre-k) Classroom Observation Tool (COT) designed for use in a data-based coaching model. We examined psychometric characteristics of the COT and explored how coaches and teachers used the COT goal-setting system. The study included 193 coaches working with 3,909 pre-k teachers in a statewide professional development program. Classrooms served 3 and 4 year olds (n = 56,390) enrolled mostly in Title I, Head Start, and other need-based pre-k programs. Coaches used the COT during a 2-hr observation at the beginning of the academic year. Teachers collected progress-monitoring data on children's language, literacy, and math outcomes three times during the year. Results indicated a theoretically supported eight-factor structure of the COT across language, literacy, and math instructional domains. Overall interrater reliability among coaches was good (.75). Although correlations with an established teacher observation measure were small, significant positive relations between COT scores and children's literacy outcomes indicate promising predictive validity. Patterns of goal-setting behaviors indicate teachers and coaches set an average of 43.17 goals during the academic year, and coaches reported that 80.62% of goals were met. Both coaches and teachers reported the COT was a helpful measure for enhancing quality of Tier 1 instruction. Limitations of the current study and implications for research and data-based coaching efforts are discussed. PsycINFO Database Record (c) 2013 APA, all rights reserved.

The surgical safety checklist and patient outcomes after surgery: a prospective observational cohort study, systematic review and meta-analysis.

PubMed

Abbott, T E F; Ahmad, T; Phull, M K; Fowler, A J; Hewson, R; Biccard, B M; Chew, M S; Gillies, M; Pearse, R M

2018-01-01

The surgical safety checklist is widely used to improve the quality of perioperative care. However, clinicians continue to debate the clinical effectiveness of this tool. Prospective analysis of data from the International Surgical Outcomes Study (ISOS), an international observational study of elective in-patient surgery, accompanied by a systematic review and meta-analysis of published literature. The exposure was surgical safety checklist use. The primary outcome was in-hospital mortality and the secondary outcome was postoperative complications. In the ISOS cohort, a multivariable multi-level generalized linear model was used to test associations. To further contextualise these findings, we included the results from the ISOS cohort in a meta-analysis. Results are reported as odds ratios (OR) with 95% confidence intervals. We included 44 814 patients from 497 hospitals in 27 countries in the ISOS analysis. There were 40 245 (89.8%) patients exposed to the checklist, whilst 7508 (16.8%) sustained ≥1 postoperative complications and 207 (0.5%) died before hospital discharge. Checklist exposure was associated with reduced mortality [odds ratio (OR) 0.49 (0.32-0.77); P<0.01], but no difference in complication rates [OR 1.02 (0.88-1.19); P=0.75]. In a systematic review, we screened 3732 records and identified 11 eligible studies of 453 292 patients including the ISOS cohort. Checklist exposure was associated with both reduced postoperative mortality [OR 0.75 (0.62-0.92); P<0.01; I 2 =87%] and reduced complication rates [OR 0.73 (0.61-0.88); P<0.01; I 2 =89%). Patients exposed to a surgical safety checklist experience better postoperative outcomes, but this could simply reflect wider quality of care in hospitals where checklist use is routine. Copyright © 2017 British Journal of Anaesthesia. Published by Elsevier Ltd. All rights reserved.

Jackhammer esophagus: Observations on a European cohort.

PubMed

Herregods, T V K; Smout, A J P M; Ooi, J L S; Sifrim, D; Bredenoord, A J

2017-04-01

With the advent of high-resolution manometry (HRM), a new diagnosis, jackhammer esophagus, was introduced. Little is known about this rare condition, and the relationship between symptoms and hypercontractility is not always straightforward. The aim of our study was to describe a large cohort of patients with jackhammer esophagus and to investigate whether manometric findings are associated with the presence of symptoms. All patients from 06, 2014 until 12, 2015 seen at two tertiary centers with at least one hypercontractile swallow (distal contractile integral [DCI] >8000 mm Hg/s/cm) on HRM were analyzed. Patients with ≥20% premature swallows, or patients with another diagnosis explaining their symptoms were excluded. Of the 34 patients identified with jackhammer esophagus, most suffered from dysphagia (67.6%) and/or chest pain (47.1%). The symptom chest pain was not associated with any of the manometric findings, whereas dysphagia was associated with the DCI of the hypercontractile swallows and with intrabolus pressure. In addition, all patients who had an isolated DCI of the lower esophageal sphincter (LES) zone >2000 mm Hg/s/cm had dysphagia. The differences in HRM and clinical characteristics between subgroups based on the contraction type (single- or multi-peaked) or based on meeting criteria of the Chicago Classification v3.0 and v2.0 were limited. The symptom dysphagia is accompanied with strong contractions of the LES, signs of a possible outflow obstruction, and a very high DCI. The presence of a multipeaked contraction seems to be of limited relevance, and caution is warranted in labeling patients with one hypercontractile swallow as normal. © 2016 John Wiley & Sons Ltd.

Estimation of Genetic Relationships Between Individuals Across Cohorts and Platforms: Application to Childhood Height.

PubMed

Fedko, Iryna O; Hottenga, Jouke-Jan; Medina-Gomez, Carolina; Pappa, Irene; van Beijsterveldt, Catharina E M; Ehli, Erik A; Davies, Gareth E; Rivadeneira, Fernando; Tiemeier, Henning; Swertz, Morris A; Middeldorp, Christel M; Bartels, Meike; Boomsma, Dorret I

2015-09-01

Combining genotype data across cohorts increases power to estimate the heritability due to common single nucleotide polymorphisms (SNPs), based on analyzing a Genetic Relationship Matrix (GRM). However, the combination of SNP data across multiple cohorts may lead to stratification, when for example, different genotyping platforms are used. In the current study, we address issues of combining SNP data from different cohorts, the Netherlands Twin Register (NTR) and the Generation R (GENR) study. Both cohorts include children of Northern European Dutch background (N = 3102 + 2826, respectively) who were genotyped on different platforms. We explore imputation and phasing as a tool and compare three GRM-building strategies, when data from two cohorts are (1) just combined, (2) pre-combined and cross-platform imputed and (3) cross-platform imputed and post-combined. We test these three strategies with data on childhood height for unrelated individuals (N = 3124, average age 6.7 years) to explore their effect on SNP-heritability estimates and compare results to those obtained from the independent studies. All combination strategies result in SNP-heritability estimates with a standard error smaller than those of the independent studies. We did not observe significant difference in estimates of SNP-heritability based on various cross-platform imputed GRMs. SNP-heritability of childhood height was on average estimated as 0.50 (SE = 0.10). Introducing cohort as a covariate resulted in ≈2 % drop. Principal components (PCs) adjustment resulted in SNP-heritability estimates of about 0.39 (SE = 0.11). Strikingly, we did not find significant difference between cross-platform imputed and combined GRMs. All estimates were significant regardless the use of PCs adjustment. Based on these analyses we conclude that imputation with a reference set helps to increase power to estimate SNP-heritability by combining cohorts of the same ethnicity genotyped on different platforms. However

Cohort Profile: Sympathetic activity and Ambulatory Blood Pressure in Africans (SABPA) prospective cohort study.

PubMed

Malan, Leoné; Hamer, Mark; Frasure-Smith, Nancy; Steyn, Hendrik S; Malan, Nicolaas T

2015-12-01

Adapting to an over-demanding stressful urban environment may exhaust the psychophysiological resources to cope with these demands, and lead to sympathetic nervous system dysfunction. The evidence that an urban-dwelling lifestyle may be detrimental to the cardiometabolic health of Africans motivated the design of the Sympathetic activity and Ambulatory Blood Pressure in African Prospective cohort study. We aimed to determine neural mechanistic pathways involved in emotional distress and vascular remodelling. The baseline sample included 409 teachers representing a bi-ethnic sex cohort from South Africa. The study was conducted in 2008-09 and repeated after 3-year follow-up in 2011-12, with an 87.8% successful follow-up rate. Seasonal changes were avoided and extensive clinical assessments were performed in a well-controlled setting. Data collection included sociodemographics, lifestyle habits, psychosocial battery and genetic analysis, mental stress responses mimicking daily life stress (blood pressure and haemostatic, cardiometabolic, endothelial and stress hormones). Target organ damage was assessed in the brain, heart, kidney, blood vessels and retina. A unique highly phenotyped cohort is presented that can address the role of a hyperactive sympathetic nervous system and neural response pathways contributing to the burden of cardiometabolic diseases in Africans. © The Author 2014. Published by Oxford University Press on behalf of the International Epidemiological Association.

Mammographic breast density and risk of breast cancer in women with atypical hyperplasia: an observational cohort study from the Mayo Clinic Benign Breast Disease (BBD) cohort.

PubMed

Vierkant, Robert A; Degnim, Amy C; Radisky, Derek C; Visscher, Daniel W; Heinzen, Ethan P; Frank, Ryan D; Winham, Stacey J; Frost, Marlene H; Scott, Christopher G; Jensen, Matthew R; Ghosh, Karthik; Manduca, Armando; Brandt, Kathleen R; Whaley, Dana H; Hartmann, Lynn C; Vachon, Celine M

2017-01-31

Atypical hyperplasia (AH) and mammographic breast density (MBD) are established risk factors for breast cancer (BC), but their joint contributions are not well understood. We examine associations of MBD and BC by histologic impression, including AH, in a subcohort of women from the Mayo Clinic Benign Breast Disease Cohort. Women with a diagnosis of BBD and mammogram between 1985 and 2001 were eligible. Histologic impression was assessed via pathology review and coded as non-proliferative disease (NP), proliferative disease without atypia (PDWA) and AH. MBD was assessed clinically using parenchymal pattern (PP) or BI-RADS criteria and categorized as low, moderate or high. Percent density (PD) was also available for a subset of women. BC and clinical information were obtained by questionnaires, medical records and the Mayo Clinic Tumor Registry. Women were followed from date of benign biopsy to BC, death or last contact. Standardized incidence ratios (SIRs) compared the observed number of BCs to expected counts. Cox regression estimated multivariate-adjusted MBD hazard ratios. Of the 6271 women included in the study, 1132 (18.0%) had low MBD, 2921 (46.6%) had moderate MBD, and 2218 (35.4%) had high MBD. A total of 3532 women (56.3%) had NP, 2269 (36.2%) had PDWA and 470 (7.5%) had AH. Over a median follow-up of 14.3 years, 528 BCs were observed. The association of MBD and BC risk differed by histologic impression (p-interaction = 0.03), such that there was a strong MBD and BC association among NP (p < 0.001) but non-significant associations for PDWA (p = 0.27) and AH (p = 0.96). MBD and BC associations for AH women were not significant within subsets defined by type of MBD measure (PP vs. BI-RADS), age at biopsy, number of foci of AH, type of AH (lobular vs. ductal) and body mass index, and after adjustment for potential confounding variables. Women with atypia who also had high PD (>50%) demonstrated marginal evidence of increased BC risk (SIR 4

Tackle-related injury rates and nature of injuries in South African Youth Week tournament rugby union players (under-13 to under-18): an observational cohort study

PubMed Central

Burger, Nicholas; Lambert, Mike I; Viljoen, Wayne; Brown, James C; Readhead, Clint; Hendricks, Sharief

2014-01-01

Objectives The tackle situation is most often associated with the high injury rates in rugby union. Tackle injury epidemiology in rugby union has previously been focused on senior cohorts but less is known about younger cohorts. The aim of this study was to report on the nature and rates of tackle-related injuries in South African youth rugby union players representing their provinces at national tournaments. Design Observational cohort study. Setting Four South African Youth Week tournaments (under-13 Craven Week, under-16 Grant Khomo Week, under-18 Academy Week, under-18 Craven Week). Participants Injury data were collected from 3652 youth rugby union players (population at risk) in 2011 and 2012. Outcome measures Tackle-related injury severity (‘time-loss’ and ‘medical attention’), type and location, injury rate per 1000 h (including 95% CIs). Injury rate ratios (IRR) were calculated and modelled using a Poisson regression. A χ2 analysis was used to detect linear trends between injuries and increasing match quarters. Results The 2012 under-13 Craven Week had a significantly greater ‘time-loss’ injury rate when compared with the 2012 under-18 Academy Week (IRR=4.43; 95% CI 2.13 to 9.21, p<0.05) and under-18 Craven Week (IRR=3.52; 95% CI 1.54 to 8.00, p<0.05). The Poisson regression also revealed a higher probability of ‘overall’ (‘time-loss’ and ‘medical attention’ combined) and ‘time-loss’ tackle-related injuries occurring at the under-13 Craven Week. The proportion of ‘overall’ and ‘time-loss’ injuries increased significantly with each quarter of the match when all four tournaments were combined (p<0.05). Conclusions There was a difference in the tackle-related injury rate between the under-13 tournament and the two under-18 tournaments, and the tackle-related injury rate was higher in the final quarter of matches. Ongoing injury surveillance is required to better interpret these findings. Injury prevention strategies

Psychological interventions for post-traumatic stress disorder in people living with HIV in Resource poor settings: a systematic review.

PubMed

Verhey, Ruth; Chibanda, Dixon; Brakarsh, Jonathan; Seedat, Soraya

2016-10-01

Post-traumatic stress disorder is pervasive in low- and middle-income countries. There is evidence to suggest that post-traumatic stress disorder is more common among people living with HIV than non-infected matched controls. We carried out a systematic review of interventions for adult post-traumatic stress disorder from resource poor settings with a focus on people living with HIV. We included all studies that investigated interventions for adult post-traumatic stress disorder from resource poor settings with a focus on interventions that were either randomised controlled trials or observational cohort studies carried out from 1980 to May 2015. Of the 25 articles that were identified for full review, two independent reviewers identified seven studies that met our study inclusion criteria. All randomised controlled trials (RCT) (n = 6) used cognitive behavioural therapy-based interventions and focused on people living with HIV in resource poor settings. There was only one study focusing on the use of lay counsellors to address post-traumatic stress disorder but core competencies were not described. There were no intervention studies from Africa, only an observational cohort study from Rwanda. Rigorously evaluated interventions for adult post-traumatic stress disorder in people living with HIV are rare. Most were undertaken in resource poor settings located in high-income countries. There is a need for research on the development and implementation of appropriate interventions for post-traumatic stress disorder in people living with HIV in low- and middle-income countries. © 2016 John Wiley & Sons Ltd.

Natural Language Processing for Asthma Ascertainment in Different Practice Settings.

PubMed

Wi, Chung-Il; Sohn, Sunghwan; Ali, Mir; Krusemark, Elizabeth; Ryu, Euijung; Liu, Hongfang; Juhn, Young J

We developed and validated NLP-PAC, a natural language processing (NLP) algorithm based on predetermined asthma criteria (PAC) for asthma ascertainment using electronic health records at Mayo Clinic. To adapt NLP-PAC in a different health care setting, Sanford Children Hospital, by assessing its external validity. The study was designed as a retrospective cohort study that used a random sample of 2011-2012 Sanford Birth cohort (n = 595). Manual chart review was performed on the cohort for asthma ascertainment on the basis of the PAC. We then used half of the cohort as a training cohort (n = 298) and the other half as a blind test cohort to evaluate the adapted NLP-PAC algorithm. Association of known asthma-related risk factors with the Sanford-NLP algorithm-driven asthma ascertainment was tested. Among the eligible test cohort (n = 297), 160 (53%) were males, 268 (90%) white, and the median age was 2.3 years (range, 1.5-3.1 years). NLP-PAC, after adaptation, and the human abstractor identified 74 (25%) and 72 (24%) subjects, respectively, with 66 subjects identified by both approaches. Sensitivity, specificity, positive predictive value, and negative predictive value for the NLP algorithm in predicting asthma status were 92%, 96%, 89%, and 97%, respectively. The known risk factors for asthma identified by NLP (eg, smoking history) were similar to the ones identified by manual chart review. Successful implementation of NLP-PAC for asthma ascertainment in 2 different practice settings demonstrates the feasibility of automated asthma ascertainment leveraging electronic health record data with a potential to enable large-scale, multisite asthma studies to improve asthma care and research. Copyright © 2017 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

An Uncertainty Data Set for Passive Microwave Satellite Observations of Warm Cloud Liquid Water Path

NASA Astrophysics Data System (ADS)

Greenwald, Thomas J.; Bennartz, Ralf; Lebsock, Matthew; Teixeira, João.

2018-04-01

The first extended comprehensive data set of the retrieval uncertainties in passive microwave observations of cloud liquid water path (CLWP) for warm oceanic clouds has been created for practical use in climate applications. Four major sources of systematic errors were considered over the 9-year record of the Advanced Microwave Scanning Radiometer-EOS (AMSR-E): clear-sky bias, cloud-rain partition (CRP) bias, cloud-fraction-dependent bias, and cloud temperature bias. Errors were estimated using a unique merged AMSR-E/Moderate resolution Imaging Spectroradiometer Level 2 data set as well as observations from the Cloud-Aerosol Lidar with Orthogonal Polarization and the CloudSat Cloud Profiling Radar. To quantify the CRP bias more accurately, a new parameterization was developed to improve the inference of CLWP in warm rain. The cloud-fraction-dependent bias was found to be a combination of the CRP bias, an in-cloud bias, and an adjacent precipitation bias. Globally, the mean net bias was 0.012 kg/m2, dominated by the CRP and in-cloud biases, but with considerable regional and seasonal variation. Good qualitative agreement between a bias-corrected AMSR-E CLWP climatology and ship observations in the Northeast Pacific suggests that the bias estimates are reasonable. However, a possible underestimation of the net bias in certain conditions may be due in part to the crude method used in classifying precipitation, underscoring the need for an independent method of detecting rain in warm clouds. This study demonstrates the importance of combining visible-infrared imager data and passive microwave CLWP observations for estimating uncertainties and improving the accuracy of these observations.

An Uncertainty Data Set for Passive Microwave Satellite Observations of Warm Cloud Liquid Water Path

PubMed Central

Bennartz, Ralf; Lebsock, Matthew; Teixeira, João

2018-01-01

Abstract The first extended comprehensive data set of the retrieval uncertainties in passive microwave observations of cloud liquid water path (CLWP) for warm oceanic clouds has been created for practical use in climate applications. Four major sources of systematic errors were considered over the 9‐year record of the Advanced Microwave Scanning Radiometer‐EOS (AMSR‐E): clear‐sky bias, cloud‐rain partition (CRP) bias, cloud‐fraction‐dependent bias, and cloud temperature bias. Errors were estimated using a unique merged AMSR‐E/Moderate resolution Imaging Spectroradiometer Level 2 data set as well as observations from the Cloud‐Aerosol Lidar with Orthogonal Polarization and the CloudSat Cloud Profiling Radar. To quantify the CRP bias more accurately, a new parameterization was developed to improve the inference of CLWP in warm rain. The cloud‐fraction‐dependent bias was found to be a combination of the CRP bias, an in‐cloud bias, and an adjacent precipitation bias. Globally, the mean net bias was 0.012 kg/m2, dominated by the CRP and in‐cloud biases, but with considerable regional and seasonal variation. Good qualitative agreement between a bias‐corrected AMSR‐E CLWP climatology and ship observations in the Northeast Pacific suggests that the bias estimates are reasonable. However, a possible underestimation of the net bias in certain conditions may be due in part to the crude method used in classifying precipitation, underscoring the need for an independent method of detecting rain in warm clouds. This study demonstrates the importance of combining visible‐infrared imager data and passive microwave CLWP observations for estimating uncertainties and improving the accuracy of these observations. PMID:29938146

The Hokkaido Birth Cohort Study on Environment and Children's Health: cohort profile-updated 2017.

PubMed

Kishi, Reiko; Araki, Atsuko; Minatoya, Machiko; Hanaoka, Tomoyuki; Miyashita, Chihiro; Itoh, Sachiko; Kobayashi, Sumitaka; Ait Bamai, Yu; Yamazaki, Keiko; Miura, Ryu; Tamura, Naomi; Ito, Kumiko; Goudarzi, Houman

2017-05-18

The Hokkaido Study on Environment and Children's Health is an ongoing study consisting of two birth cohorts of different population sizes: the Sapporo cohort and the Hokkaido cohort. Our primary study goals are (1) to examine the effects of low-level environmental chemical exposures on birth outcomes, including birth defects and growth retardation; (2) to follow the development of allergies, infectious diseases, and neurobehavioral developmental disorders and perform a longitudinal observation of child development; (3) to identify high-risk groups based on genetic susceptibility to environmental chemicals; and (4) to identify the additive effects of various chemicals, including tobacco smoking. The purpose of this report is to update the progress of the Hokkaido Study, to summarize the recent results, and to suggest future directions. In particular, this report provides the basic characteristics of the cohort populations, discusses the population remaining in the cohorts and those who were lost to follow-up at birth, and introduces the newly added follow-up studies and case-cohort study design. In the Sapporo cohort of 514 enrolled pregnant women, various specimens, including maternal and cord blood, maternal hair, and breast milk, were collected for the assessment of exposures to dioxins, polychlorinated biphenyls, organochlorine pesticides, perfluoroalkyl substances, phthalates, bisphenol A, and methylmercury. As follow-ups, face-to-face neurobehavioral developmental tests were conducted at several different ages. In the Hokkaido cohort of 20,926 enrolled pregnant women, the prevalence of complicated pregnancies and birth outcomes, such as miscarriage, stillbirth, low birth weight, preterm birth, and small for gestational age were examined. The levels of exposure to environmental chemicals were relatively low in these study populations compared to those reported previously. We also studied environmental chemical exposure in association with health outcomes

An interactive environment for the analysis of large Earth observation and model data sets

NASA Technical Reports Server (NTRS)

Bowman, Kenneth P.; Walsh, John E.; Wilhelmson, Robert B.

1994-01-01

Envision is an interactive environment that provides researchers in the earth sciences convenient ways to manage, browse, and visualize large observed or model data sets. Its main features are support for the netCDF and HDF file formats, an easy to use X/Motif user interface, a client-server configuration, and portability to many UNIX workstations. The Envision package also provides new ways to view and change metadata in a set of data files. It permits a scientist to conveniently and efficiently manage large data sets consisting of many data files. It also provides links to popular visualization tools so that data can be quickly browsed. Envision is a public domain package, freely available to the scientific community. Envision software (binaries and source code) and documentation can be obtained from either of these servers: ftp://vista.atmos.uiuc.edu/pub/envision/ and ftp://csrp.tamu.edu/pub/envision/. Detailed descriptions of Envision capabilities and operations can be found in the User's Guide and Reference Manuals distributed with Envision software.

Use of a Simple Criteria Set for Guiding Echocardiography in Nosocomial Staphylococcus aureus Bacteremia

PubMed Central

Fowler, Vance G.; Rieg, Siegbert; Peyerl-Hoffmann, Gabriele; Birkholz, Hanna; Hellmich, Martin; Kern, Winfried V.; Seifert, Harald

2011-01-01

(see the editorial commentary and Soriano and Mensa, on pages 10–12.) Background. Infective endocarditis (IE) is a severe complication in patients with nosocomial Staphylococcus aureus bacteremia (SAB). We sought to develop and validate criteria to identify patients at low risk for the development of IE in whom transesophageal echocardiography (TEE) might be dispensable. Methods. Consecutive patients with nosocomial SAB from independent cohorts in Europe (Invasive S. aureus Infection Cohort [INSTINCT]) and North America (S. aureus Bacteremia Group [SABG]) were evaluated for the presence of clinical criteria predicting an increased risk for the development of IE (ie, prolonged bacteremia of >4 days' duration, presence of a permanent intracardiac device, hemodialysis dependency, spinal infection, and nonvertebral osteomyelitis). Patients were observed closely for clinical signs and symptoms of IE during hospitalization and a 3-month follow-up period. Results. IE was present in 13 (4.3%) of 304 patients in the INSTINCT cohort and in 40 (9.3%) of 432 patients in the SABG cohort. Within 14 days after the first positive blood culture result, echocardiography was performed in 39.8% and 57.4% of patients in the INSTINCT and SABG cohorts, respectively. In patients with IE, the most common clinical prediction criteria present were prolonged bacteremia (69.2% vs 90% for INSTINCT vs SABG, respectively) and presence of a permanent intracardiac device (53.8% vs 32.5%). In total, 13 of 13 patients in the INSTINCT cohort and 39 of 40 patients in the SABG cohort with documented IE fulfilled at least 1 criterion (sensitivity, 100% vs. 97.5%; negative predictive value, 100% vs 99.2%). Conclusions. A simple criteria set for patients with nosocomial SAB can identify patients at low risk of IE. Patients who meet these criteria may not routinely require TEE. PMID:21653295

Clinical Research Methodology 2: Observational Clinical Research.

PubMed

Sessler, Daniel I; Imrey, Peter B

2015-10-01

Case-control and cohort studies are invaluable research tools and provide the strongest feasible research designs for addressing some questions. Case-control studies usually involve retrospective data collection. Cohort studies can involve retrospective, ambidirectional, or prospective data collection. Observational studies are subject to errors attributable to selection bias, confounding, measurement bias, and reverse causation-in addition to errors of chance. Confounding can be statistically controlled to the extent that potential factors are known and accurately measured, but, in practice, bias and unknown confounders usually remain additional potential sources of error, often of unknown magnitude and clinical impact. Causality-the most clinically useful relation between exposure and outcome-can rarely be definitively determined from observational studies because intentional, controlled manipulations of exposures are not involved. In this article, we review several types of observational clinical research: case series, comparative case-control and cohort studies, and hybrid designs in which case-control analyses are performed on selected members of cohorts. We also discuss the analytic issues that arise when groups to be compared in an observational study, such as patients receiving different therapies, are not comparable in other respects.

A Query Language for Handling Big Observation Data Sets in the Sensor Web

NASA Astrophysics Data System (ADS)

Autermann, Christian; Stasch, Christoph; Jirka, Simon; Koppe, Roland

2017-04-01

The Sensor Web provides a framework for the standardized Web-based sharing of environmental observations and sensor metadata. While the issue of varying data formats and protocols is addressed by these standards, the fast growing size of observational data is imposing new challenges for the application of these standards. Most solutions for handling big observational datasets currently focus on remote sensing applications, while big in-situ datasets relying on vector features still lack a solid approach. Conventional Sensor Web technologies may not be adequate, as the sheer size of the data transmitted and the amount of metadata accumulated may render traditional OGC Sensor Observation Services (SOS) unusable. Besides novel approaches to store and process observation data in place, e.g. by harnessing big data technologies from mainstream IT, the access layer has to be amended to utilize and integrate these large observational data archives into applications and to enable analysis. For this, an extension to the SOS will be discussed that establishes a query language to dynamically process and filter observations at storage level, similar to the OGC Web Coverage Service (WCS) and it's Web Coverage Processing Service (WCPS) extension. This will enable applications to request e.g. spatial or temporal aggregated data sets in a resolution it is able to display or it requires. The approach will be developed and implemented in cooperation with the The Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research whose catalogue of data compromises marine observations of physical, chemical and biological phenomena from a wide variety of sensors, including mobile (like research vessels, aircrafts or underwater vehicles) and stationary (like buoys or research stations). Observations are made with a high temporal resolution and the resulting time series may span multiple decades.

Identifying genetic variants that affect viability in large cohorts

PubMed Central

Berisa, Tomaz; Day, Felix R.; Perry, John R. B.

2017-01-01

A number of open questions in human evolutionary genetics would become tractable if we were able to directly measure evolutionary fitness. As a step towards this goal, we developed a method to examine whether individual genetic variants, or sets of genetic variants, currently influence viability. The approach consists in testing whether the frequency of an allele varies across ages, accounting for variation in ancestry. We applied it to the Genetic Epidemiology Research on Adult Health and Aging (GERA) cohort and to the parents of participants in the UK Biobank. Across the genome, we found only a few common variants with large effects on age-specific mortality: tagging the APOE ε4 allele and near CHRNA3. These results suggest that when large, even late-onset effects are kept at low frequency by purifying selection. Testing viability effects of sets of genetic variants that jointly influence 1 of 42 traits, we detected a number of strong signals. In participants of the UK Biobank of British ancestry, we found that variants that delay puberty timing are associated with a longer parental life span (P~6.2 × 10−6 for fathers and P~2.0 × 10−3 for mothers), consistent with epidemiological studies. Similarly, variants associated with later age at first birth are associated with a longer maternal life span (P~1.4 × 10−3). Signals are also observed for variants influencing cholesterol levels, risk of coronary artery disease (CAD), body mass index, as well as risk of asthma. These signals exhibit consistent effects in the GERA cohort and among participants of the UK Biobank of non-British ancestry. We also found marked differences between males and females, most notably at the CHRNA3 locus, and variants associated with risk of CAD and cholesterol levels. Beyond our findings, the analysis serves as a proof of principle for how upcoming biomedical data sets can be used to learn about selection effects in contemporary humans. PMID:28873088

A Cohort, Is a Cohort, Is a Cohort...or Is It?

ERIC Educational Resources Information Center

Pemberton, Cynthia Lee A.; Akkary, Rima Karami

2010-01-01

This paper presents findings from a multi-year qualitative study based upon life-history narratives of women pursuing doctoral degrees in Educational Leadership. This paper focuses on findings specific to educational cohort models, and suggests that perhaps, at least for women, naturally emergent cohorts--born of relationships of choice--may be…

Cohort profile: a data linkage cohort to examine health service profiles of people with intellectual disability in New South Wales, Australia.

PubMed

Reppermund, Simone; Srasuebkul, Preeyaporn; Heintze, Theresa; Reeve, Rebecca; Dean, Kimberlie; Emerson, Eric; Coyne, David; Snoyman, Phillip; Baldry, Eileen; Dowse, Leanne; Szanto, Tracey; Sara, Grant; Florio, Tony; Trollor, Julian N

2017-04-12

People with intellectual disability are a minority group who experience poorer physical and mental health than the general population and have difficulty accessing healthcare services. There is lack of knowledge about healthcare service needs and gaps experienced by people with intellectual disability. This study aims to interrogate a large linked administrative data set containing hospital admissions, presentations to emergency departments (ED) and mortality data to provide evidence to inform the development of improved health and mental health services for this population. A retrospective cohort of people with intellectual disability (n=51 452) from New South Wales (NSW), Australia, to explore health and mental health profiles, mortality, pattern of health service use and associated costs between 2005 and 2013. The cohort is drawn from: the Disability Services Minimum Data Set; Admitted Patients Data Collection; Emergency Department Data Collection, Australian Bureau of Statistics Death Registry and Registry of Births, Deaths and Marriages. Mental health service usage among those with intellectual disability will be compared to a cohort of people who used mental health services (n=1 073 139) and service usage other than for mental health will be compared with published data from the general population. The median age of the cohort was 24 at the time of the last hospital admission and 21 at the last ED presentation. The cohort has a higher proportion of men than women and accounts for 0.6% of the NSW population in 2011. Over 70% had up to 5 ED presentations and hospitalisations between 2005 and 2012. A high proportion of people with intellectual disability live in the most disadvantaged neighbourhoods. Results will be used to inform the development of more responsive healthcare, including improved interactions between health, social and disability supports. More generally, the results will assist the development of more inclusive policy frameworks for people

Cohort profile: a data linkage cohort to examine health service profiles of people with intellectual disability in New South Wales, Australia

PubMed Central

Reppermund, Simone; Srasuebkul, Preeyaporn; Heintze, Theresa; Reeve, Rebecca; Dean, Kimberlie; Emerson, Eric; Coyne, David; Snoyman, Phillip; Baldry, Eileen; Dowse, Leanne; Szanto, Tracey; Sara, Grant; Florio, Tony

2017-01-01

Purpose People with intellectual disability are a minority group who experience poorer physical and mental health than the general population and have difficulty accessing healthcare services. There is lack of knowledge about healthcare service needs and gaps experienced by people with intellectual disability. This study aims to interrogate a large linked administrative data set containing hospital admissions, presentations to emergency departments (ED) and mortality data to provide evidence to inform the development of improved health and mental health services for this population. Participants A retrospective cohort of people with intellectual disability (n=51 452) from New South Wales (NSW), Australia, to explore health and mental health profiles, mortality, pattern of health service use and associated costs between 2005 and 2013. The cohort is drawn from: the Disability Services Minimum Data Set; Admitted Patients Data Collection; Emergency Department Data Collection, Australian Bureau of Statistics Death Registry and Registry of Births, Deaths and Marriages. Mental health service usage among those with intellectual disability will be compared to a cohort of people who used mental health services (n=1 073 139) and service usage other than for mental health will be compared with published data from the general population. Findings to date The median age of the cohort was 24 at the time of the last hospital admission and 21 at the last ED presentation. The cohort has a higher proportion of men than women and accounts for 0.6% of the NSW population in 2011. Over 70% had up to 5 ED presentations and hospitalisations between 2005 and 2012. A high proportion of people with intellectual disability live in the most disadvantaged neighbourhoods. Future plans Results will be used to inform the development of more responsive healthcare, including improved interactions between health, social and disability supports. More generally, the results will assist the

Evaluation of paradoxical TB–associated IRIS with the use of standardized case definitions for resource limited settings

PubMed Central

Eshun-Wilson, Ingrid; Havers, Fiona; Nachega, Jean B; Prozesky, Hans W; Taljaard, Jantjie J; Zeier, Michele D; Cotton, Mark; Simon, Gary; Soentjens, Patrick

2011-01-01

Objective Standardized case definitions have recently been proposed by the International Network for the Study of HIV-associated IRIS (INSHI) for use in resource-limited settings. We evaluated paradoxical TB-associated IRIS in a large cohort from a TB endemic setting with the use of these case definitions. Design A retrospective cohort analysis. Methods We reviewed records from 1250 South African patients who initiated anti-retroviral therapy (ART) over a five-year period. Results 333 (27%) of the patients in the cohort had prevalent TB at the initiation of ART. Of 54 possible paradoxical TB-associated IRIS cases, 35 fulfilled the INSHI case definitions (11% of TB cases). Conclusions INSHI standardised case definitions were used successfully in identifying paradoxical TB-associated IRIS in this cohort and resulted in a similar proportion of TB IRIS cases (11%) as that reported in previous studies from resource-limited settings (8-13%). This case definition should be evaluated prospectively. PMID:20160249

How to Establish and Follow up a Large Prospective Cohort Study in the 21st Century--Lessons from UK COSMOS.

PubMed

Toledano, Mireille B; Smith, Rachel B; Brook, James P; Douglass, Margaret; Elliott, Paul

2015-01-01

Large-scale prospective cohort studies are invaluable in epidemiology, but they are increasingly difficult and costly to establish and follow-up. More efficient methods for recruitment, data collection and follow-up are essential if such studies are to remain feasible with limited public and research funds. Here, we discuss how these challenges were addressed in the UK COSMOS cohort study where fixed budget and limited time frame necessitated new approaches to consent and recruitment between 2009-2012. Web-based e-consent and data collection should be considered in large scale observational studies, as they offer a streamlined experience which benefits both participants and researchers and save costs. Commercial providers of register and marketing data, smartphones, apps, email, social media, and the internet offer innovative possibilities for identifying, recruiting and following up cohorts. Using examples from UK COSMOS, this article sets out the dos and don'ts for today's cohort studies and provides a guide on how best to take advantage of new technologies and innovative methods to simplify logistics and minimise costs. Thus a more streamlined experience to the benefit of both research participants and researchers becomes achievable.

How to Establish and Follow up a Large Prospective Cohort Study in the 21st Century - Lessons from UK COSMOS

PubMed Central

Toledano, Mireille B.; Smith, Rachel B.; Brook, James P.; Douglass, Margaret; Elliott, Paul

2015-01-01

Large-scale prospective cohort studies are invaluable in epidemiology, but they are increasingly difficult and costly to establish and follow-up. More efficient methods for recruitment, data collection and follow-up are essential if such studies are to remain feasible with limited public and research funds. Here, we discuss how these challenges were addressed in the UK COSMOS cohort study where fixed budget and limited time frame necessitated new approaches to consent and recruitment between 2009-2012. Web-based e-consent and data collection should be considered in large scale observational studies, as they offer a streamlined experience which benefits both participants and researchers and save costs. Commercial providers of register and marketing data, smartphones, apps, email, social media, and the internet offer innovative possibilities for identifying, recruiting and following up cohorts. Using examples from UK COSMOS, this article sets out the dos and don’ts for today's cohort studies and provides a guide on how best to take advantage of new technologies and innovative methods to simplify logistics and minimise costs. Thus a more streamlined experience to the benefit of both research participants and researchers becomes achievable. PMID:26147611

Nonkin in older adults' personal networks: more important among later cohorts?

PubMed

Suanet, Bianca; van Tilburg, Theo G; Broese van Groenou, Marjolein I

2013-07-01

Research on age-related changes in personal networks has found compelling evidence for socioemotional selectivity theory and exchange theory holding that older adults experience a decline in less emotionally close nonkin relations as they age. However, recent societal developments are likely to have increased the salience of nonkin relations. We hypothesize that age-related decline in the proportion of nonkin in personal networks has been delayed or is slower in late birth cohorts of older adults compared with earlier cohorts. Seven observations by the Longitudinal Aging Study Amsterdam covering a time span of 17 years since 1992 were analyzed using multilevel regression analysis. The sample had 12,949 person-year observations from 3,516 respondents born between 1908 and 1937. Age-related decline in the proportion of nonkin is absent for cohorts born after 1922 and large for cohorts born in 1922 and before. Mediating variables for health and other resources did not explain cohort differences in age-related change. The salience of nonkin relationships is likely to have increased due to societal changes, resulting in absence or delay of decline in later cohorts. The findings raise the need for a reevaluation of old age and the creation of new theoretical perspectives.

Gender-Specific Combination HIV Prevention for Youth in High-Burden Settings: The MP3 Youth Observational Pilot Study Protocol.

PubMed

Buttolph, Jasmine; Inwani, Irene; Agot, Kawango; Cleland, Charles M; Cherutich, Peter; Kiarie, James N; Osoti, Alfred; Celum, Connie L; Baeten, Jared M; Nduati, Ruth; Kinuthia, John; Hallett, Timothy B; Alsallaq, Ramzi; Kurth, Ann E

2017-03-08

Nearly three decades into the epidemic, sub-Saharan Africa (SSA) remains the region most heavily affected by human immunodeficiency virus (HIV), with nearly 70% of the 34 million people living with HIV globally residing in the region. In SSA, female and male youth (15 to 24 years) are at a disproportionately high risk of HIV infection compared to adults. As such, there is a need to target HIV prevention strategies to youth and to tailor them to a gender-specific context. This protocol describes the process for the multi-staged approach in the design of the MP3 Youth pilot study, a gender-specific, combination, HIV prevention intervention for youth in Kenya. The objective of this multi-method protocol is to outline a rigorous and replicable methodology for a gender-specific combination HIV prevention pilot study for youth in high-burden settings, illustrating the triangulated methods undertaken to ensure that age, sex, and context are integral in the design of the intervention. The mixed-methods, cross-sectional, longitudinal cohort pilot study protocol was developed by first conducting a systematic review of the literature, which shaped focus group discussions around prevention package and delivery options, and that also informed age- and sex- stratified mathematical modeling. The review, qualitative data, and mathematical modeling created a triangulated evidence base of interventions to be included in the pilot study protocol. To design the pilot study protocol, we convened an expert panel to select HIV prevention interventions effective for youth in SSA, which will be offered in a mobile health setting. The goal of the pilot study implementation and evaluation is to apply lessons learned to more effective HIV prevention evidence and programming. The combination HIV prevention package in this protocol includes (1) offering HIV testing and counseling for all youth; (2) voluntary medical circumcision and condoms for males; (3) pre-exposure prophylaxis (Pr

Exploring generational cohort work satisfaction in hospital nurses.

PubMed

Gordon, Pamela Ann

2017-07-03

Purpose Although extensive research exists regarding job satisfaction, many previous studies used a more restrictive, quantitative methodology. The purpose of this qualitative study is to capture the perceptions of hospital nurses within generational cohorts regarding their work satisfaction. Design/methodology/approach A preliminary qualitative, phenomenological study design explored hospital nurses' work satisfaction within generational cohorts - Baby Boomers (1946-1964), Generation X (1965-1980) and Millennials (1981-2000). A South Florida hospital provided the venue for the research. In all, 15 full-time staff nurses, segmented into generational cohorts, participated in personal interviews to determine themes related to seven established factors of work satisfaction: pay, autonomy, task requirements, administration, doctor-nurse relationship, interaction and professional status. Findings An analysis of the transcribed interviews confirmed the importance of the seven factors of job satisfaction. Similarities and differences between the generational cohorts related to a combination of stages of life and generational attributes. Practical implications The results of any qualitative research relate only to the specific venue studied and are not generalizable. However, the information gleaned from this study is transferable and other organizations are encouraged to conduct their own research and compare the results. Originality/value This study is unique, as the seven factors from an extensively used and highly respected quantitative research instrument were applied as the basis for this qualitative inquiry into generational cohort job satisfaction in a hospital setting.

An observational cohort study of patients with newly diagnosed digital ulcer disease secondary to systemic sclerosis registered in the EUSTAR database.

PubMed

Brand, Monika; Hollaender, Rebecca; Rosenberg, Daniel; Scott, Martin; Hunsche, Elke; Tyndall, Alan; Denaro, Valentina; Carreira, Patricia; Varju, Cecilia; Gabrielli, Barbara; Zingarelli, Stefania; Caramaschi, Paola; Simic-Pasalic, Katarina; Müller-Ladner, Ulf; Vasile, Massimiliano; Mihai, Carina; Rosato, Edoardo; Vacca, Alessandra; Zenone, Thierry; Mohamed, Walid A; Ancuta, Codrina; Zampogna, Giuseppe; Rednic, Simona; Jabaar, Nadia; Belloli, Laura; Pozzi, Maria R; Foti, Rosario; Walker, Ulrich A

2015-01-01

This study describes clinical characteristics, prognostic factors, and quality of life in patients with newly diagnosed (incident) digital ulcers (DU). Observational cohort study of 189 consecutive SSc patients with incident DU diagnosis identified from the EUSTAR database (22 centres in 10 countries). Data were collected from medical charts and during one prospective visit between 01/2004 and 09/2010. Median age at DU diagnosis was 51 years, majority of patients were female (88%), and limited cutaneous SSc was the most common subtype (61%). At incident DU diagnosis, 41% of patients had one DU and 59% had ≥2 DU; at the prospective visit 52% had DU. Pulmonary arterial hypertension (PAH) and multiple DU at diagnosis were associated with presence of any DU at the prospective visit (odds ratios: 4.34 and 1.32). During the observation period (median follow-up was 2 years) 127 patients had ≥1 hospitalisation. The event rate of new DU per person-year was 0.66, of DU-associated complications was 0.10, and of surgical or diagnostic procedures was 0.12. At the prospective visit, patients with ≥1 DU reported impairment in daily activities by 57%, those with 0 DU by 37%. The mean difference between patients with or without DU in the SF-36 physical component was 2.2, and in the mental component 1.4. DU patients were not routinely prescribed endothelin receptor antagonists or prostanoids. This real world cohort demonstrates that DU require hospital admission, and impair daily activity. PAH and multiple DU at diagnosis were associated with future occurrence of DU.

AstroNet: A Tool Set for Simultaneous, Multi-Site Observations of Astronomical Objects

NASA Technical Reports Server (NTRS)

Chakrabarti, Supriya

1995-01-01

Earth-based, fully automatic "robotic" telescopes have been in routine operation for a number of years. As their number grows and their distribution becomes global, increasing attention is being given to forming networks of various sorts that will allow them, as a group, to make observations 24 hours a day in both hemispheres. We have suggested that telescopes based in space be part of this network. We further suggested that any telescope on this network be capable of asking, almost in real time, that other robotic telescopes perform support observations for them. When a target of opportunity required support observations, the system would determine which telescope(s) in the network would be most appropriate to make the observations and formulate a request to do so. Because the network would be comprised of telescopes located in widely distributed regions, this system would guarantee continuity of observations This report summarizes our efforts under this contract. We proposed to develop a set of data collection and display tools to aid simultaneous observation of astronomical targets from a number of observing sites. We planned to demonstrate the usefulness of this toolset for simultaneous multi-site observation of astronomical targets. Possible candidates or the proposed demonstration included the Extreme Ultraviolet Explorer (EUVE), International Ultraviolet Explorer (IUE), and ALEXIS, sounding rocket experiments. Ground-based observatories operated by the University of California, Berkeley, the Jet Propulsion Laboratory, and Fairborn Observatory in Mesa, Arizona were to be used to demonstrate the proposed concept. Although the demonstration was to have involved astronomical investigations, the tools were to have been applicable to a large number of scientific disciplines. The software tools and systems developed as a result of the work were to have been made available to the scientific community.

Cognitive, emotional and social phenotyping of mice in an observer-independent setting.

PubMed

Dere, Ekrem; Ronnenberg, Anja; Tampe, Björn; Arinrad, Sahab; Schmidt, Manuela; Zeisberg, Elisabeth; Ehrenreich, Hannelore

2018-04-01

Based on the intellicage paradigm, we have developed a novel cognitive, emotional and social phenotyping battery that permits comprehensive standardized behavioral characterization of mice in an experimenter-independent social setting. Evaluation of this battery in a large number of male and female C57BL/6 wildtype mice, tested in >20 independent cohorts, revealed high reproducibility of the behavioral readouts and may serve as future reference tool. We noticed robust sex-specific differences in general activity, cognitive and emotional behavior, but not regarding preference for social pheromones. Specifically, female mice revealed higher activity, decreased sucrose preference, impaired reversal and place-time-reward learning. Furthermore, female mice reacted more sensitively than males to reward-withdrawal showing a negative emotional contrast/Crespi-effect. In a series of validation experiments, we tested mice with different pathologies, including neuroligin-3 deficient mice (male Nlgn3 y/- and female Nlgn3 +/- ) for autistic behavior, oligodendrocyte-specific erythropoietin receptor knockout (oEpoR -/- ) mice for cognitive impairment, as well as mouse models of renal failure (unilateral ureteral obstruction and 5/6 nephrectomy) and of type 2 diabetes (ApoE -/- ) - for delineating potentially confounding effects of motivational factors (thirst, glucose-craving) on learning and memory assessments. As prominent features, we saw in Nlgn3 mutants reduced preference for social pheromones, whereas oEpoR -/- mice showed learning deficits in place or reversal learning tasks. Renal failure led to increased water intake, and diabetic metabolism to enhanced glucose preference, limiting interpretation of hereon based learning and memory performance in these mice. The phenotyping battery presented here may be well-suited as high-throughput multifaceted diagnostic instrument for translational neuropsychiatry and behavioral genetics. Copyright © 2018. Published by Elsevier Inc.

Activities of daily living in nursing home and home care settings: a retrospective 1-year cohort study.

PubMed

Lee, Tae Wha; Cho, Eunhee; Yim, Eun Shil; Lee, Hye Sun; Ko, Yu Kyung; Kim, Bok Nam; Kim, Sinhye

2015-02-01

Korea introduced universal long-term care insurance (LTCI) for physically dependent older adults in 2008. Older adults, their family members, and policy makers in Korea want to know patient outcomes in different care modalities because older adults who have a similar functional status and LTC needs can choose either nursing home care or home care. The aim of this study was to compare activities of daily living (ADLs) in nursing home care and home care settings for physically dependent older adults in Korea. A retrospective 1-year cohort study using national LTCI data. This study used the LTCI dataset from the National Health Insurance Service in Korea. Participants were identified from among those in the LTCI dataset who enrolled from July 2008 to June 2010. We extracted a sample consisting of 22,557 older adults who consistently received either nursing home care (n = 11,678) or home care (n = 10,879) for 1 year. The outcome variable was change in ADLs after 1 year. Covariates were an older adult's home geographical region, LTC level, age, sex, primary caregiver, Medicaid beneficiary status, bedridden status, medical diagnosis, baseline ADLs, cognitive function, behavioral problems, nursing and special treatment, and rehabilitation needs. Multiple regression analysis of all participants unmatched and a paired t-test with a propensity-score-matched cohort were performed to explain the association of changes in ADLs with the types of LTC. Multiple regression analysis with all participants (n = 22,557) unmatched showed that compared with older adults who received home care, those who received nursing home care had deteriorated further in terms of ADLs after 1 year (β = 0.44108, P < .0001). After propensity-score matching, paired t-test analysis also found that the ADLs of older adults had deteriorated less in the home care group compared with the nursing home group after 1 year (P < .0001). The ADLs of older adults who received home care showed significantly less

An intercomparison of multidecadal observational and reanalysis data sets for global total ozone trends and variability analysis

NASA Astrophysics Data System (ADS)

Bai, Kaixu; Chang, Ni-Bin; Shi, Runhe; Yu, Huijia; Gao, Wei

2017-07-01

A four-step adaptive ozone trend estimation scheme is proposed by integrating multivariate linear regression (MLR) and ensemble empirical mode decomposition (EEMD) to analyze the long-term variability of total column ozone from a set of four observational and reanalysis total ozone data sets, including the rarely explored ERA-Interim total ozone reanalysis, from 1979 to 2009. Consistency among the four data sets was first assessed, indicating a mean relative difference of 1% and root-mean-square error around 2% on average, with respect to collocated ground-based total ozone observations. Nevertheless, large drifts with significant spatiotemporal inhomogeneity were diagnosed in ERA-Interim after 1995. To emphasize long-term trends, natural ozone variations associated with the solar cycle, quasi-biennial oscillation, volcanic aerosols, and El Niño-Southern Oscillation were modeled with MLR and then removed from each total ozone record, respectively, before performing EEMD analyses. The resulting rates of change estimated from the proposed scheme captured the long-term ozone variability well, with an inflection time of 2000 clearly detected. The positive rates of change after 2000 suggest that the ozone layer seems to be on a healing path, but the results are still inadequate to conclude an actual recovery of the ozone layer, and more observational evidence is needed. Further investigations suggest that biases embedded in total ozone records may significantly impact ozone trend estimations by resulting in large uncertainty or even negative rates of change after 2000.

Predicting inpatient violence in acute psychiatric wards using the Brøset-Violence-Checklist: a multicentre prospective cohort study.

PubMed

Abderhalden, C; Needham, I; Miserez, B; Almvik, R; Dassen, T; Haug, H-J; Fischer, J E

2004-08-01

The Norwegian Brøset-Violence-Checklist (BVC) is one of the few instruments that is suitable for short-term prediction of violence of psychiatric inpatients by nursing staff in routine care. The instrument assesses the presence or absence of six behaviours or states frequently observed before a violent incident. We conducted a study to elucidate whether the predictive properties of the BVC are retained in other psychiatric settings than the original north-Norwegian validation dataset. During their admission period, 219 consecutive patients admitted to six acute psychiatric wards were assessed as to the risk for attack using a German version of the BVC (BVC-G). Data on preventive measures were concurrently collected. Aggressive incidents were registered using an instrument equivalent to the Staff Observation of Aggression Scale (SOAS-R). Fourteen attacks towards staff were observed with incident severity ranging from 5 to 18 of a possible 22 points. BVC-G sensitivity was 64.3%, the specificity 93.9%, the positive predictive value 11.1%, and the area under the receiver operating characteristic curve 0.88. In some false positive cases intense preventive measures had been implemented. The predictive accuracy of the BVC-G proved consistent with the Norwegian original.

Improvements in HIV treatment outcomes among indigenous and non-indigenous people who use illicit drugs in a Canadian setting

PubMed Central

Milloy, M-J; King, Alexandra; Kerr, Thomas; Adams, Evan; Samji, Hasina; Guillemi, Silvia; Wood, Evan; Montaner, Julio

2016-01-01

Introduction In many settings worldwide, members of indigenous groups experience a disproportionate burden of HIV. In Canada, there is an urgent need to improve HIV treatment outcomes for indigenous people living with HIV (IPLWH), to not only reduce HIV/AIDS-associated morbidity and mortality but also curb elevated rates of viral transmission. Thus, by comparing indigenous and non-indigenous participants in an ongoing longitudinal cohort of HIV-positive people who use illicit drugs, we sought to investigate longitudinal changes in three HIV treatment indicators for IPLWH who use illicit drugs during a community-wide treatment-as-prevention (TasP) initiative in British Columbia, Canada. Methods We used data from the ACCESS study, an ongoing observational prospective cohort of HIV-positive illicit drug users recruited from community settings in Vancouver, British Columbia. Cohort data are linked to comprehensive retrospective and prospective clinical records in a setting of no-cost HIV/AIDS treatment and care. We used multivariable generalized estimating equations (GEE) to evaluate longitudinal changes in the proportion of participants with exposure to antiretroviral therapy (ART) in the previous 180 days, optimal adherence to ART (i.e. ≥95% vs. <95%) and non-detectable HIV-1 RNA viral load (VL <50 copies/mL plasma). Results Between 2005 and 2014, 845 individuals were recruited, including 326 (39%) self-reporting any indigenous ancestry, and contributed 6732 interviews and 13,495 VL measurements. Among indigenous participants, the proportion with recent ART increased from 51 to 94% and non-detectable VL from 23 to 65%. In multivariable models, later interview period was positively associated with recent ART (adjusted odds ratio (AOR)=1.16 per interview period, 95% confidence interval (CI): 1.11 to 1.20) and non-detectable VL (AOR=1.07, 95% CI: 1.04 to 1.10). In adjusted models comparing indigenous and non-indigenous participants, we did not observe differences

Improvements in HIV treatment outcomes among indigenous and non-indigenous people who use illicit drugs in a Canadian setting.

PubMed

Milloy, M-J; King, Alexandra; Kerr, Thomas; Adams, Evan; Samji, Hasina; Guillemi, Silvia; Wood, Evan; Montaner, Julio

2016-01-01

In many settings worldwide, members of indigenous groups experience a disproportionate burden of HIV. In Canada, there is an urgent need to improve HIV treatment outcomes for indigenous people living with HIV (IPLWH), to not only reduce HIV/AIDS-associated morbidity and mortality but also curb elevated rates of viral transmission. Thus, by comparing indigenous and non-indigenous participants in an ongoing longitudinal cohort of HIV-positive people who use illicit drugs, we sought to investigate longitudinal changes in three HIV treatment indicators for IPLWH who use illicit drugs during a community-wide treatment-as-prevention (TasP) initiative in British Columbia, Canada. We used data from the ACCESS study, an ongoing observational prospective cohort of HIV-positive illicit drug users recruited from community settings in Vancouver, British Columbia. Cohort data are linked to comprehensive retrospective and prospective clinical records in a setting of no-cost HIV/AIDS treatment and care. We used multivariable generalized estimating equations (GEE) to evaluate longitudinal changes in the proportion of participants with exposure to antiretroviral therapy (ART) in the previous 180 days, optimal adherence to ART (i.e. ≥ 95% vs. < 95%) and non-detectable HIV-1 RNA viral load (VL <50 copies/mL plasma). Between 2005 and 2014, 845 individuals were recruited, including 326 (39%) self-reporting any indigenous ancestry, and contributed 6732 interviews and 13,495 VL measurements. Among indigenous participants, the proportion with recent ART increased from 51 to 94% and non-detectable VL from 23 to 65%. In multivariable models, later interview period was positively associated with recent ART (adjusted odds ratio (AOR) = 1.16 per interview period, 95% confidence interval (CI): 1.11 to 1.20) and non-detectable VL (AOR = 1.07, 95% CI: 1.04 to 1.10). In adjusted models comparing indigenous and non-indigenous participants, we did not observe differences between the two groups (all

Natural history of Niemann-Pick disease type C in a multicentre observational retrospective cohort study.

PubMed

Wraith, J E; Guffon, N; Rohrbach, M; Hwu, W L; Korenke, G C; Bembi, B; Luzy, C; Giorgino, R; Sedel, F

2009-11-01

Niemann-Pick disease type C (NP-C) is a devastating genetic disorder characterised by progressive neurological deterioration. However, data on the progression of neurological manifestations, particularly across different patient age-of-disease onsets, are limited. This is an observational retrospective cohort study designed to assess the progression of neurological disease in patients with NP-C. Physicians were asked to retrospectively complete a web-based questionnaire for each patient, at diagnosis and at up to three follow-up visits. An NP-C-specific disability scale was used to measure disease progression. The scale comprised four key parameters of neurological disease progression; ambulation, manipulation, language and swallowing. Disease progression was evaluated based on the annual rate of change in each parameter and the composite score using a linear mixed model analysis, and by classifying patients according to the number of worsened parameters during the observation period. Data were collected from 57 patients. The rate of deterioration was similar across the four individual parameters of the disability scale. The mean (95% CI) annual disease progression was +0.12 (0.09, 0.15) units. Among patients with a time interval of at least 1 year between diagnosis and last visit (n=49), 42 (86%) patients had progressed disease and 7 (14%) patients had stable disease. Disease progression was consistently more rapid in patients diagnosed in early childhood, compared with those diagnosed in late childhood, or with juvenile or adult presentation. In conclusion, our findings showed a progression in all four parameters of the disability scale, representing a continuous, unbroken progression of neurological manifestations.

Lung cancer risk comparison among male smokers between the "six-prefecture cohort" in Japan and the British physicians' cohort.

PubMed

Mizuno, S; Akiba, S; Hirayama, T

1989-12-01

We estimated the effective duration of cigarette smoking using the data of lung cancer mortality among male smokers of a large-scale cohort study in Japan and evaluated its role in the lung cancer risk difference between male smokers of the Japanese cohort and the British physicians' cohort. By selecting male cohort members who answered that they had started smoking at ages 18-22 (average = 20.3), the subjects of our analysis, which numbered 49,013, were made relatively homogeneous in terms of age at which smoking was started. Assuming lung cancer mortality to be proportional to the 4.5th power of the effective duration of cigarette smoking, i.e., (age-theta)4.5, as was proposed on the basis of the British cohort study by Doll and Peto, the parameter theta was estimated to be 29.4 for male smokers aged 40-64 in 1966; therefore, the estimated duration of cigarette smoking was, on average, 9.1 years (95% confidence interval = 5.8-11.6) shorter than that calculated from the reported age at which smoking was started. Our findings suggested that the low lung cancer mortality relative to daily cigarette consumption in Japan resulted from the shorter duration of cigarette smoking in the Japanese cohort, possibly due to the severe shortage of cigarettes during and shortly after World War II. Once the effective duration of cigarette smoking was adjusted, lung cancer mortality in the range of 5-34 cigarettes per day was fairly comparable to that observed among the cohort of male British physicians.

Examining the effectiveness of parental strategies to overcome bedwetting: an observational cohort study

PubMed Central

Grzeda, Mariusz T; Heron, Jon; Tilling, Kate; Wright, Anne; Joinson, Carol

2017-01-01

Objective To examine whether a range of common strategies used by parents to overcome bedwetting in 7½-year-old children (including lifting, restricting drinks before bedtime, regular daytime toilet trips, rewards, showing displeasure and using protection pants) are effective in reducing the risk of bedwetting at 9½ years. Design Prospective cohort study. Setting General community. Participants The starting sample included 1258 children (66.7% boys and 33.2% girls) who were still bedwetting at 7½ years. Outcome measure Risk of bedwetting at 9½ years. Results Using propensity score-based methods, we found that two of the parental strategies used at 7½ years were associated with an increased risk of bedwetting at 9½ years, after adjusting the model for child and family variables and other parental strategies: lifting (risk difference=0.106 (95% CI 0.009 to 0.202), ie, there is a 10.6% (0.9% to 20.2%) increase in risk of bedwetting at 9½ years among children whose parents used lifting compared with children whose parents did not use this strategy) and restricting drinks before bedtime (0.123 (0.021 to 0.226)). The effect of using the other parental strategies was in either direction (an increase or decrease in the risk of bedwetting at 9½ years), for example, showing displeasure (−0.052 (−0.214 to 0.110)). When we re-analysed the data using multivariable regression analysis, the results were mostly consistent with the propensity score-based methods. Conclusion These findings provide evidence that common strategies used to overcome bedwetting in 7½-year-olds are not effective in reducing the risk of bedwetting at 9½ years. Parents should be encouraged to seek professional advice for their child’s bedwetting rather than persisting with strategies that may be ineffective. PMID:28710225

Establishment of a binational cohort to study Helicobacter pylori infection in children.

PubMed

Goodman, Karen J; O'Rourke, Kathleen; Day, R Sue; Redlinger, Thomas; Sanchez, Julie; Wang, Constance; Campos, Armando; de la Rosa, Manuel

2003-01-01

Chronic Helicobacter (H.) pylori infection, typically of childhood onset, causes upper digestive tract diseases of major impact among socioeconomically marginalized populations. This infection is common in children from ethnic minorities in the United States, and particularly so in immigrant children from Mexico. Prevention measures for H. pylori infection do not yet exist, given limited understanding of what causes either acute or persistent infection. To address this gap, we initiated the Pasitos Cohort Study to follow children from low-income families in the border region that includes El Paso County, Texas, and Ciudad Juarez, Chihuahua. The children were enrolled prior to birth, and are examined at 6-month intervals to observe the natural history of H. pylori infection, and to identify risk factors for acquisition, recurrence, and persistence. This report details the study methods, describes how the cohort was established, and discusses the challenges of compliance with follow up in the border setting. Between April 1998 and October 2000, 1,288 pregnant women were screened for eligibility; 807 of 994 eligible women consented to participate. Birth documentation was obtained for 615 infants, and 472 entered follow up. Successful follow up of this cohort requires resources, including a well-trained, dedicated staff, and incentives, to facilitate and motivate long-term participation. Future findings from this ongoing study will help to fill critical gaps in knowledge regarding the epidemiology of H. pylori infection, and will contribute to the identification of prevention strategies.

The long-term financial consequences of breast cancer: a Danish registry-based cohort study.

PubMed

Jensen, Laura Schärfe; Overgaard, Charlotte; Bøggild, Henrik; Garne, Jens Peter; Lund, Thomas; Overvad, Kim; Fonager, Kirsten

2017-10-30

A breast cancer diagnosis affects an individual's affiliation to labour market, but the long-term consequences of breast cancer on income in a Danish setting have not been examined. The present study investigated whether breast cancer affected future income among Danish women that participated in the work force. We also examined the roles of sociodemographic factors and prior psychiatric medical treatment. This registry-based cohort study was based on information retrieved from linked Danish nationwide registries. We compared the incomes of 13,101 women (aged 30-59 years) diagnosed with breast cancer (exposed) to those of 60,819 women without breast cancer (unexposed). Changes in income were examined during a 10-year follow-up; for each follow-up year, we calculated the mean annual income and the relative change compared to the income earned one year prior to diagnosis. Expected changes in Danish female income, according to calendar year and age, were estimated based on information from Statistics Denmark. For exposed and unexposed groups, the observed income changes were dichotomized to those above and those below the expected change in income in the Danish female population. We examined the impact of breast cancer on income each year of follow-up with logistic regression models. Analyses were stratified according to educational level, marital status, and prior psychiatric medical treatment. Breast cancer had a temporary negative effect on income. The effect was largest during the first three years after diagnosis; thereafter, the gap narrowed between exposed and unexposed cohorts. The odds ratio for an increase in income in the cancer cohort compared to the cancer-free cohort was 0.81 (95% CI 0.77-0.84) after three years. After seven years, no significant difference was observed between cohorts. Stratified analyses demonstrated that the negative effect of breast cancer on income lasted longest among women with high educational levels. Being single or having

Dunes on planet Tatooine: Observation of barchan migration at the Star Wars film set in Tunisia

NASA Astrophysics Data System (ADS)

Lorenz, Ralph D.; Gasmi, Nabil; Radebaugh, Jani; Barnes, Jason W.; Ori, Gian G.

2013-11-01

Sand dune migration is documented with a readily-available tool (Google Earth) near Chott El Gharsa, just north-west of Tozeur, Tunisia. As fiducial markers we employ a set of buildings used to portray the fictional city Mos Espa. This set of ~ 20 buildings over roughly a hectare was constructed in 1997 for the movie Star Wars Episode 1 - The Phantom Menace. The site now lies between the arms of a large “pudgy” barchan dune, which has been documented via satellite imaging in 2002, 2004, 2008 and 2009 to have moved from ~ 140 m away to only ~ 10 m away. Visits by the authors to the site in 2009 and 2011 confirm the barchan to be in a threatening position: a smaller set nearby was substantially damaged by being overrun by dunes circa 2004. The migration rate of ~ 15 m/yr decreases over the observation period, possibly as a result of increased local rainfall, and is consistent with barchan migration rates observed at other locations worldwide. The migration rate of this and two other barchans suggests sand transport of ~ 50 m3/m/yr, somewhat higher than would be suggested by traditional wind rose calculations: we explore possible reasons for this discrepancy. Because of the link to popular science fiction, the site may be of pedagogical interest in teaching remote sensing and geomorphic change. We also note that nearby playa surfaces and agricultural areas have a time-variable appearance. The site's popularity as a destination for Star Wars enthusiasts results in many photographs being posted on the internet, providing a rich set of in-situ imagery for continued monitoring in the absence of dedicated field visits.

Retrospective cohort study of a microelectronics and business machine facility.

PubMed

Silver, Sharon R; Pinkerton, Lynne E; Fleming, Donald A; Jones, James H; Allee, Steven; Luo, Lian; Bertke, Stephen J

2014-04-01

We examined health outcomes among 34,494 workers employed at a microelectronics and business machine facility 1969-2001. Standardized mortality ratio (SMR) and standardized incidence ratios were used to evaluate health outcomes in the cohort and Cox regression modeling to evaluate relations between scores for occupational exposures and outcomes of a priori interest. Just over 17% of the cohort (5,966 people) had died through 2009. All cause, all cancer, and many cause-specific SMRs showed statistically significant deficits. In hourly males, SMRs were significantly elevated for non-Hodgkin's lymphoma and rectal cancer. Salaried males had excess testicular cancer incidence. Pleural cancer and mesothelioma excesses were observed in workers hired before 1969, but no available records substantiate use of asbestos in manufacturing processes. A positive, statistically significant relation was observed between exposure scores for tetrachloroethylene and nervous system diseases. Few significant exposure-outcome relations were observed, but risks from occupational exposures cannot be ruled out due to data limitations and the relative youth of the cohort. © 2013 Wiley Periodicals, Inc.

German-wide prospective DACAPO cohort of survivors of the acute respiratory distress syndrome (ARDS): a cohort profile

PubMed Central

Dodoo-Schittko, Frank; Brandstetter, Susanne; Brandl, Magdalena; Blecha, Sebastian; Quintel, Michael; Weber-Carstens, Steffen; Kluge, Stefan; Kirschning, Thomas; Muders, Thomas; Bercker, Sven; Ellger, Björn; Arndt, Christian; Meybohm, Patrick; Adamzik, Michael; Goldmann, Anton; Karagiannidis, Christian; Bein, Thomas

2018-01-01

Purpose While most research focuses on the association between medical characteristics and residual morbidity of survivors of the acute respiratory distress syndrome (ARDS), little is known about the relation between potentially modifiable intensive care unit (ICU) features and the course of health-related quality of life (HRQoL). Accordingly, the DACAPO study was set up to elucidate the influence of quality of intensive care on HRQoL and return to work (RtW) in survivors of ARDS. The continued follow-up of these former ICU patients leads to the establishment of the DACAPO (survivor) cohort. Participants Sixty-one ICUs all over Germany recruited patients with ARDS between September 2014 and April 2016. Inclusion criteria were: (1) age older than 18 years and (2) ARDS diagnosis according to the ‘Berlin definition’. No further inclusion or exclusion criteria were applied. 1225 patients with ARDS could be included in the DACAPO ICU sample. Subsequently, the 876 survivors at ICU discharge form the actual DACAPO cohort. Findings to date The recruitment of the participants of the DACAPO cohort and the baseline data collection has been completed. The care-related data of the DACAPO cohort reveal a high proportion of adverse events (in particular, hypoglycaemia and reintubation). However, evidence-based supportive measures were applied frequently. Future plans Three months, 6 months and 1 year after ICU admission a follow-up assessment is conducted. The instruments of the follow-up questionnaires comprise the domains: (A) HRQoL, (B) RtW, (C) general disability, (D) psychiatric symptoms and (E) social support. Additionally, an annual follow-up of the DACAPO cohort focusing on HRQoL, psychiatric symptoms and healthcare utilisation will be conducted. Furthermore, several add-on projects affecting medical issues are envisaged. Trial registration number NCT02637011. PMID:29622574

Feasibility and safety of setting up a donor breastmilk bank in a neonatal prem unit in a resource limited setting: An observational, longitudinal cohort study.

PubMed

Coutsoudis, Irene; Adhikari, Miriam; Nair, Nadia; Coutsoudis, Anna

2011-05-20

The beneficial effects of human milk on decreasing rates of paediatric infections such as necrotizing enterocolitis (NEC) and sepsis have been clearly demonstrated. Donor breastmilk has been encouraged as the milk of choice when a mother's own breastmilk is not available. The objectives of this study were to assess feasibility of providing donor breastmilk to infants in a resource limited Neonatal Prem Unit (NPU). In addition we sought to determine whether donor breastmilk could be safely pasteurized and administered to infants without any adverse events. Low birth weight infants < 1800 g and under 32 weeks gestational age were followed up in the NPU over a 3 week period; feeding data and morbidity data was collected in order to determine if there were any adverse events associated with donor breastmilk. Samples of pasteurized breastmilk were cultured to check for any bacterial contamination. 191 infants met the inclusion criteria of whom 96 received their mother's own breastmilk. Of the 95 infants who were potentially eligible to receive donor milk, only 40 did in fact receive donor milk. There was no evidence of bacterial contamination in the samples analyzed, and no evidence of adverse events from feeding with donor breastmilk. It is feasible to supply donor breastmilk to infants in an NPU in a resource limited setting, however staff needs to be sensitized to the importance of donor breastmilk to improve uptake rates. Secondly we showed that it is possible to supply donor breastmilk according to established guidelines with no adverse events therefore making it possible to prevent NEC and other side effects often associated with formula feeding of premature infants.

The international primary ciliary dyskinesia cohort (iPCD Cohort): methods and first results.

PubMed

Goutaki, Myrofora; Maurer, Elisabeth; Halbeisen, Florian S; Amirav, Israel; Barbato, Angelo; Behan, Laura; Boon, Mieke; Casaulta, Carmen; Clement, Annick; Crowley, Suzanne; Haarman, Eric; Hogg, Claire; Karadag, Bulent; Koerner-Rettberg, Cordula; Leigh, Margaret W; Loebinger, Michael R; Mazurek, Henryk; Morgan, Lucy; Nielsen, Kim G; Omran, Heymut; Schwerk, Nicolaus; Scigliano, Sergio; Werner, Claudius; Yiallouros, Panayiotis; Zivkovic, Zorica; Lucas, Jane S; Kuehni, Claudia E

2017-01-01

Data on primary ciliary dyskinesia (PCD) epidemiology is scarce and published studies are characterised by low numbers. In the framework of the European Union project BESTCILIA we aimed to combine all available datasets in a retrospective international PCD cohort (iPCD Cohort).We identified eligible datasets by performing a systematic review of published studies containing clinical information on PCD, and by contacting members of past and current European Respiratory Society Task Forces on PCD. We compared the contents of the datasets, clarified definitions and pooled them in a standardised format.As of April 2016 the iPCD Cohort includes data on 3013 patients from 18 countries. It includes data on diagnostic evaluations, symptoms, lung function, growth and treatments. Longitudinal data are currently available for 542 patients. The extent of clinical details per patient varies between centres. More than 50% of patients have a definite PCD diagnosis based on recent guidelines. Children aged 10-19 years are the largest age group, followed by younger children (≤9 years) and young adults (20-29 years).This is the largest observational PCD dataset available to date. It will allow us to answer pertinent questions on clinical phenotype, disease severity, prognosis and effect of treatments, and to investigate genotype-phenotype correlations. Copyright ©ERS 2017.

The international primary ciliary dyskinesia cohort (iPCD Cohort): methods and first results

PubMed Central

Goutaki, Myrofora; Maurer, Elisabeth; Halbeisen, Florian S.; Amirav, Israel; Barbato, Angelo; Behan, Laura; Boon, Mieke; Casaulta, Carmen; Clement, Annick; Crowley, Suzanne; Haarman, Eric; Hogg, Claire; Karadag, Bulent; Koerner-Rettberg, Cordula; Leigh, Margaret W.; Loebinger, Michael R.; Mazurek, Henryk; Morgan, Lucy; Nielsen, Kim G.; Omran, Heymut; Schwerk, Nicolaus; Scigliano, Sergio; Werner, Claudius; Yiallouros, Panayiotis; Zivkovic, Zorica; Lucas, Jane S.

2017-01-01

Data on primary ciliary dyskinesia (PCD) epidemiology is scarce and published studies are characterised by low numbers. In the framework of the European Union project BESTCILIA we aimed to combine all available datasets in a retrospective international PCD cohort (iPCD Cohort). We identified eligible datasets by performing a systematic review of published studies containing clinical information on PCD, and by contacting members of past and current European Respiratory Society Task Forces on PCD. We compared the contents of the datasets, clarified definitions and pooled them in a standardised format. As of April 2016 the iPCD Cohort includes data on 3013 patients from 18 countries. It includes data on diagnostic evaluations, symptoms, lung function, growth and treatments. Longitudinal data are currently available for 542 patients. The extent of clinical details per patient varies between centres. More than 50% of patients have a definite PCD diagnosis based on recent guidelines. Children aged 10–19 years are the largest age group, followed by younger children (≤9 years) and young adults (20–29 years). This is the largest observational PCD dataset available to date. It will allow us to answer pertinent questions on clinical phenotype, disease severity, prognosis and effect of treatments, and to investigate genotype–phenotype correlations. PMID:28052956

Cohort Profile: Antiretroviral Therapy Cohort Collaboration (ART-CC)

PubMed Central

May, Margaret T; Ingle, Suzanne M; Costagliola, Dominique; Justice, Amy C; de Wolf, Frank; Cavassini, Matthias; D’Arminio Monforte, Antonella; Casabona, Jordi; Hogg, Robert S; Mocroft, Amanda; Lampe, Fiona C; Dabis, François; Fätkenheuer, Gerd; Sterling, Timothy R; del Amo, Julia; Gill, M John; Crane, Heidi M; Saag, Michael S; Guest, Jodie; Brodt, Hans-Reinhard; Sterne, Jonathan AC

2014-01-01

The advent of effective combination antiretroviral therapy (ART) in 1996 resulted in fewer patients experiencing clinical events, so that some prognostic analyses of individual cohort studies of human immunodeficiency virus-infected individuals had low statistical power. Because of this, the Antiretroviral Therapy Cohort Collaboration (ART-CC) of HIV cohort studies in Europe and North America was established in 2000, with the aim of studying the prognosis for clinical events in acquired immune deficiency syndrome (AIDS) and the mortality of adult patients treated for HIV-1 infection. In 2002, the ART-CC collected data on more than 12,000 patients in 13 cohorts who had begun combination ART between 1995 and 2001. Subsequent updates took place in 2004, 2006, 2008, and 2010. The ART-CC data base now includes data on more than 70 000 patients participating in 19 cohorts who began treatment before the end of 2009. Data are collected on patient demographics (e.g. sex, age, assumed transmission group, race/ethnicity, geographical origin), HIV biomarkers (e.g. CD4 cell count, plasma viral load of HIV-1), ART regimen, dates and types of AIDS events, and dates and causes of death. In recent years, additional data on co-infections such as hepatitis C; risk factors such as smoking, alcohol and drug use; non-HIV biomarkers such as haemoglobin and liver enzymes; and adherence to ART have been collected whenever available. The data remain the property of the contributing cohorts, whose representatives manage the ART-CC via the steering committee of the Collaboration. External collaboration is welcomed. Details of contacts are given on the ART-CC website (www.art-cohort-collaboration.org). PMID:23599235

Wind-Induced Air-Flow Patterns in an Urban Setting: Observations and Numerical Modeling

NASA Astrophysics Data System (ADS)

Sattar, Ahmed M. A.; Elhakeem, Mohamed; Gerges, Bishoy N.; Gharabaghi, Bahram; Gultepe, Ismail

2018-04-01

City planning can have a significant effect on wind flow velocity patterns and thus natural ventilation. Buildings with different heights are roughness elements that can affect the near- and far-field wind flow velocity. This paper aims at investigating the impact of an increase in building height on the nearby velocity fields. A prototype urban setting of buildings with two different heights (25 and 62.5 cm) is built up and placed in a wind tunnel. Wind flow velocity around the buildings is mapped at different heights. Wind tunnel measurements are used to validate a 3D-numerical Reynolds averaged Naviers-Stokes model. The validated model is further used to calculate the wind flow velocity patterns for cases with different building heights. It was found that increasing the height of some buildings in an urban setting can lead to the formation of large horseshoe vortices and eddies around building corners. A separation area is formed at the leeward side of the building, and the recirculation of air behind the building leads to the formation of slow rotation vortices. The opposite effect is observed in the wake (cavity) region of the buildings, where both the cavity length and width are significantly reduced, and this resulted in a pronounced increase in the wind flow velocity. A significant increase in the wind flow velocity in the wake region of tall buildings with a value of up to 30% is observed. The spatially averaged velocities around short buildings also increased by 25% compared to those around buildings with different heights. The increase in the height of some buildings is found to have a positive effect on the wind ventilation at the pedestrian level.

A cohort mortality study of employees exposed to chlorinated chemicals.

PubMed

Wong, O

1988-01-01

The cohort of this historical prospective mortality study consisted of 697 male employees at a chlorination plant. A majority of the cohort was potentially exposed to benzotrichloride, benzyl chloride, benzoyl chloride, and other related chemicals. The mortality experience of the cohort was observed from 1943 through 1982. For the cohort as a whole, no statistically significant mortality excess was detected. The overall Standardized Mortality Ratio (SMR) was 100, and the SMR for all cancers combined was 122 (not significant). The respiratory cancer SMR for the cohort as a whole was 246 (7 observed vs. 2.8 expected). The excess was of borderline statistical significance, the lower 95% confidence limit being 99. Analysis by race showed that all 7 respiratory cancer deaths came from the white male employees, with an SMR of 265 (p less than 0.05). The respiratory cancer mortality excess was higher among employees in maintenance (SMR = 229) than among those in operations or production (SMR = 178). The lung cancer mortality excess among the laboratory employees was statistically significant (SMR = 1292). However, this observation should be viewed with caution, since it was based on only 2 deaths. Further analysis indicated that the respiratory cancer mortality excess was limited to the male employees with 15 or more years of employment (SMR = 379, p less than 0.05). Based on animal data as well as other epidemiologic studies, together with the internal consistency of analysis by length of employment, the data suggest an association between the chlorination process of toluene at the plant and an increased risk of respiratory cancer.(ABSTRACT TRUNCATED AT 250 WORDS)

Parental Separation and Cardiometabolic Risk Factors in Late Adolescence: A Cross-Cohort Comparison

PubMed Central

Soares, Ana Luiza Gonçalves; Gonçalves, Helen; Matijasevich, Alicia; Sequeira, Maija; Smith, George Davey; Menezes, Ana M. B.; Assunção, Maria Cecília; Wehrmeister, Fernando C.; Fraser, Abigail; Howe, Laura D.

2017-01-01

Abstract The aim of this study was to explore the association between parental separation during childhood (up to 18 years of age) and cardiometabolic risk factors (body mass index, fat mass index, blood pressure, physical activity, smoking, and alcohol consumption) in late adolescence using a cross-cohort comparison and to explore whether associations differ according to the age at which the parental separation occurred and the presence or absence of parental conflict prior to separation. Data from the Avon Longitudinal Study of Parents and Children (ALSPAC, United Kingdom) (1991–2011) and the 1993 Pelotas Birth Cohort (Brazil) (1993–2011) were used. The associations of parental separation with children's cardiometabolic risk factors were largely null. Higher odds of daily smoking were observed in both cohorts for those adolescents whose parents separated (for ALSPAC, odds ratio = 1.46; for Pelotas Birth Cohort, odds ratio = 1.98). Some additional associations were observed in the Pelotas Birth Cohort but were generally in the opposite direction to our a priori hypothesis: Parental separation was associated with lower blood pressure and fat mass index, and with more physical activity. No consistent differences were observed when analyses were stratified by child's age at parental separation or parental conflict. PMID:28444145

Adaptive disturbance compensation finite control set optimal control for PMSM systems based on sliding mode extended state observer

NASA Astrophysics Data System (ADS)

Wu, Yun-jie; Li, Guo-fei

2018-01-01

Based on sliding mode extended state observer (SMESO) technique, an adaptive disturbance compensation finite control set optimal control (FCS-OC) strategy is proposed for permanent magnet synchronous motor (PMSM) system driven by voltage source inverter (VSI). So as to improve robustness of finite control set optimal control strategy, a SMESO is proposed to estimate the output-effect disturbance. The estimated value is fed back to finite control set optimal controller for implementing disturbance compensation. It is indicated through theoretical analysis that the designed SMESO could converge in finite time. The simulation results illustrate that the proposed adaptive disturbance compensation FCS-OC possesses better dynamical response behavior in the presence of disturbance.

Patient-as-observer approach: an alternative method for hand hygiene auditing in an ambulatory care setting.

PubMed

Le-Abuyen, Sheila; Ng, Jessica; Kim, Susie; De La Franier, Anne; Khan, Bibi; Mosley, Jane; Gardam, Michael

2014-04-01

A survey pilot asked patients to observe the hand hygiene compliance of their health care providers. Patients returned 75.1% of the survey cards distributed, and the overall hand hygiene compliance was 96.8%. Survey results and patient commentary were used to motivate hand hygiene compliance. The patient-as-observer approach appeared to be a viable alternative for hand hygiene auditing in an ambulatory care setting because it educated, engaged, and empowered patients to play a more active role in their own health care. Copyright © 2014 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

Cohort profile: Antiretroviral Therapy Cohort Collaboration (ART-CC).

PubMed

May, Margaret T; Ingle, Suzanne M; Costagliola, Dominique; Justice, Amy C; de Wolf, Frank; Cavassini, Matthias; D'Arminio Monforte, Antonella; Casabona, Jordi; Hogg, Robert S; Mocroft, Amanda; Lampe, Fiona C; Dabis, François; Fätkenheuer, Gerd; Sterling, Timothy R; del Amo, Julia; Gill, M John; Crane, Heidi M; Saag, Michael S; Guest, Jodie; Brodt, Hans-Reinhard; Sterne, Jonathan A C

2014-06-01

The advent of effective combination antiretroviral therapy (ART) in 1996 resulted in fewer patients experiencing clinical events, so that some prognostic analyses of individual cohort studies of human immunodeficiency virus-infected individuals had low statistical power. Because of this, the Antiretroviral Therapy Cohort Collaboration (ART-CC) of HIV cohort studies in Europe and North America was established in 2000, with the aim of studying the prognosis for clinical events in acquired immune deficiency syndrome (AIDS) and the mortality of adult patients treated for HIV-1 infection. In 2002, the ART-CC collected data on more than 12,000 patients in 13 cohorts who had begun combination ART between 1995 and 2001. Subsequent updates took place in 2004, 2006, 2008, and 2010. The ART-CC data base now includes data on more than 70,000 patients participating in 19 cohorts who began treatment before the end of 2009. Data are collected on patient demographics (e.g. sex, age, assumed transmission group, race/ethnicity, geographical origin), HIV biomarkers (e.g. CD4 cell count, plasma viral load of HIV-1), ART regimen, dates and types of AIDS events, and dates and causes of death. In recent years, additional data on co-infections such as hepatitis C; risk factors such as smoking, alcohol and drug use; non-HIV biomarkers such as haemoglobin and liver enzymes; and adherence to ART have been collected whenever available. The data remain the property of the contributing cohorts, whose representatives manage the ART-CC via the steering committee of the Collaboration. External collaboration is welcomed. Details of contacts are given on the ART-CC website (www.art-cohort-collaboration.org). Published by Oxford University Press on behalf of the International Epidemiological Association © The Author 2013; all rights reserved.

Canonical Naimark extension for generalized measurements involving sets of Pauli quantum observables chosen at random

NASA Astrophysics Data System (ADS)

Sparaciari, Carlo; Paris, Matteo G. A.

2013-01-01

We address measurement schemes where certain observables Xk are chosen at random within a set of nondegenerate isospectral observables and then measured on repeated preparations of a physical system. Each observable has a probability zk to be measured, with ∑kzk=1, and the statistics of this generalized measurement is described by a positive operator-valued measure. This kind of scheme is referred to as quantum roulettes, since each observable Xk is chosen at random, e.g., according to the fluctuating value of an external parameter. Here we focus on quantum roulettes for qubits involving the measurements of Pauli matrices, and we explicitly evaluate their canonical Naimark extensions, i.e., their implementation as indirect measurements involving an interaction scheme with a probe system. We thus provide a concrete model to realize the roulette without destroying the signal state, which can be measured again after the measurement or can be transmitted. Finally, we apply our results to the description of Stern-Gerlach-like experiments on a two-level system.

The association between vitamin B12, albuminuria and reduced kidney function: an observational cohort study

USDA-ARS?s Scientific Manuscript database

Background: Variants in CUBN, the gene encoding cubilin, a proximal tubular transport protein, have been associated with albuminuria and vitamin B12 (B12) deficiency. We hypothesized that low levels of B12 would be associated with albuminuria in a population-based cohort. Methods: We analyzed parti...

A retrospective cohort study of mode of delivery among public and private patients in an integrated maternity hospital setting

PubMed Central

Murphy, Deirdre J; Fahey, Tom

2013-01-01

Objective To examine the associations between mode of delivery and public versus privately funded obstetric care within the same hospital setting. Design Retrospective cohort study. Setting Urban maternity hospital in Ireland. Population A total of 30 053 women with singleton pregnancies who delivered between 2008 and 2011. Methods The study population was divided into those who booked for obstetric care within the public (n=24 574) or private clinics (n=5479). Logistic regression analyses were performed to examine the associations between operative delivery and type of care, adjusting for potential confounding factors. Main outcome measures Caesarean section (scheduled or emergency), operative vaginal delivery (vacuum or forceps), indication for caesarean section as classified by the operator. Results Compared with public patients, private patients were more likely to be delivered by caesarean section (34.4% vs 22.5%, OR 1.81; 95% CI 1.70 to 1.93) or operative vaginal delivery (20.1% vs 16.5%, OR 1.28; 95% CI 1.19 to 1.38). The greatest disparity was for scheduled caesarean sections; differences persisted for nulliparous and parous women after controlling for medical and social differences between the groups (nulliparous 11.9% vs 4.6%, adjusted (adj) OR 1.82; 95% CI 1.49 to 2.24 and parous 26% vs 12.2%, adj OR 2.08; 95% CI 1.86 to 2.32). Scheduled repeat caesarean section accounted for most of the disparity among parous patients. Maternal request per se was an uncommonly reported indication for caesarean section (35 in each group, p<0.000). Conclusions Privately funded obstetric care is associated with higher rates of operative deliveries that are not fully accounted for by medical or obstetric risk differences. PMID:24277646

Production of a long-term global water vapor and liquid water data set using ultra-fast methods to assimilate multi-satellite and radiosonde observations

NASA Technical Reports Server (NTRS)

Vonderhaar, Thomas H.; Randel, David L.; Reinke, Donald L.; Stephens, Graeme L.; Ringerud, Mark A.; Combs, Cynthia L.; Greenwald, Thomas J.; Wittmeyer, Ian L.

1995-01-01

There is a well-documented requirement for a comprehensive and accurate global moisture data set to assist many important studies in atmospheric science. Currently, atmospheric water vapor measurements are made from a variety of sources including radiosondes, aircraft and surface observations, and in recent years, by various satellite instruments. Creating a global data set from a single measuring system produces results that are useful and accurate only in specific situations and/or areas. Therefore, an accurate global moisture data set has been derived from a combination of these measurement systems. Under a NASA peer-reviewed contract, STC-METSAT produced two 5-yr (1988-1992) global data sets. One is the total column (integrated) water vapor data set and the other, a global layered water vapor data set using a combination of radiosonde observations, Television and Infrared Observation Satellite (TIROS) Operational Satellite (TOVS), and Special Sensor Microwave/Imager (SSM/I) data sets. STC-METSAT also produced a companion, global, integrated liquid water data set. The complete data set (all three products) has been named NVAP, an anachronym for NASA Water Vapor Project. STC-METSAT developed methods to process the data at a daily time scale and 1 x 1 deg spatial resolution.

Multiple imputation of missing data in nested case-control and case-cohort studies.

PubMed

Keogh, Ruth H; Seaman, Shaun R; Bartlett, Jonathan W; Wood, Angela M

2018-06-05

The nested case-control and case-cohort designs are two main approaches for carrying out a substudy within a prospective cohort. This article adapts multiple imputation (MI) methods for handling missing covariates in full-cohort studies for nested case-control and case-cohort studies. We consider data missing by design and data missing by chance. MI analyses that make use of full-cohort data and MI analyses based on substudy data only are described, alongside an intermediate approach in which the imputation uses full-cohort data but the analysis uses only the substudy. We describe adaptations to two imputation methods: the approximate method (MI-approx) of White and Royston () and the "substantive model compatible" (MI-SMC) method of Bartlett et al. (). We also apply the "MI matched set" approach of Seaman and Keogh () to nested case-control studies, which does not require any full-cohort information. The methods are investigated using simulation studies and all perform well when their assumptions hold. Substantial gains in efficiency can be made by imputing data missing by design using the full-cohort approach or by imputing data missing by chance in analyses using the substudy only. The intermediate approach brings greater gains in efficiency relative to the substudy approach and is more robust to imputation model misspecification than the full-cohort approach. The methods are illustrated using the ARIC Study cohort. Supplementary Materials provide R and Stata code. © 2018, The International Biometric Society.

Multidisciplinary assessment of post-Ebola sequelae in Guinea (Postebogui): an observational cohort study.

PubMed

Etard, Jean-François; Sow, Mamadou Saliou; Leroy, Sandrine; Touré, Abdoulaye; Taverne, Bernard; Keita, Alpha Kabinet; Msellati, Philippe; Magassouba, N'Fally; Baize, Sylvain; Raoul, Hervé; Izard, Suzanne; Kpamou, Cécé; March, Laura; Savane, Ibrahima; Barry, Moumié; Delaporte, Eric

2017-05-01

The high number of survivors from the 2013-16 west African outbreak of Ebola virus disease (EVD) has raised several new issues: long-term clinical complications, psychosocial consequences, risks of EVD reactivation, and secondary transmission due to viral persistence in body fluids. We aimed to assess long-term clinical, psychosocial, and viral outcomes in EVD survivors in Guinea. In this multidisciplinary observational cohort study, we recruited patients aged 1 year or more in four sites in Guinea (Donka National Hospital, Conakry; Macenta Prefectoral Hospital, Macenta; N'zérékoré Regional Hospital, N'zérékoré; and Forécariah Prefectoral Hospital, Forécariah) following discharge from any Ebola treatment centre in Guinea. Eligible patients had had laboratory-confirmed EVD and had then been declared clear of the virus in the blood. All consenting patients were included, with no exclusion criteria. Trained clinicians assessed patients at enrolment to the cohort, recording clinical symptoms and signs of depression. We did routine blood examinations and examined viral persistence in body fluids using RT-PCR. We did psychological evaluations using questionnaires developed for different age groups. Follow-up is planned to 2 years, and here we present findings at enrolment. Between March 23, 2015, and July 11, 2016, we recruited 802 patients, of whom 360 (45%) were male, 442 (55%) were female; 158 (20%) were younger than 18 years. The median age was 28·4 years (range 1·0-79·9, IQR 19·4-39·8). The median delay after discharge was 350 days (IQR 223-491). The most frequent symptoms were general symptoms (324 [40%] patients), musculoskeletal pain (303 [38%]), headache (278 [35%]), depression (124 [17%] of 713 responses), abdominal pain (178 [22%]), and ocular disorders (142 [18%]). More adults than children had at least one clinical symptom (505 [78%] vs 101 [64%], p<0·0003), ocular complications (124 [19%] vs 18 [11%], p=0·0200), or musculoskeletal symptoms

Use of systemic antifungals in daily clinical practice in the haematology and oncology setting: results of a prospective observational analysis.

PubMed

Metzke, Barbara; Neubauer, Werner Christian; Hieke, Stefanie; Jung, Manfred; Wäsch, Ralph; Engelhardt, Monika

2012-09-01

To assess the role of systemic antifungal drugs as well as the frequency of potential drug interactions and adverse drug events of commonly used antifungals in an unselected haematology/oncology patient cohort. A prospective analysis was performed in our haematology/oncology department between October 2006 and September 2009. Data were obtained from 250 consecutive patients who received treatment and/or prophylaxis with fluconazole (n = 191), liposomal amphotericin B (n = 105), voriconazole (n = 62), caspofungin (n = 27) and/or posaconazole (n = 22). We performed detailed reviews of patient charts and laboratory values in close cooperation with treating physicians and nursing staff and participated regularly in ward and chart rounds. Potential drug interactions were assessed using the electronic database Micromedex® 1.0 (Healthcare Series). In terms of adverse drug events, caspofungin (56%) and voriconazole (58%) revealed a slightly more favourable safety profile than liposomal amphotericin B (66%) and posaconazole (64%). We confirmed frequent nephrotoxic effects with the use of liposomal amphotericin B (20%). Regarding potential drug interactions, 97 (66%) of 147 evaluated patients were exposed to at least 1 of 22 different potentially interacting drug combinations involving systemic antifungal agents. Cyclosporine was the most prevalent potentially interacting drug in our cohort. Systemic antifungal drugs are widely used in the haematology/oncology setting and exhibit numerous potential drug interactions and adverse events in cancer patients. Our results highlight the challenges related to antifungal drugs and should valuably contribute to a safe and efficient application of this increasingly important class of drugs. Copyright © 2012 John Wiley & Sons, Ltd.

Questionnaire layout and wording influence prevalence and risk estimates of respiratory symptoms in a population cohort

PubMed Central

Ekerljung, Linda; Rönmark, Eva; Lötvall, Jan; Wennergren, Göran; Torén, Kjell; Lundbäck, Bo

2013-01-01

Objective Results of epidemiological studies are greatly influenced by the chosen methodology. The study aims to investigate how two frequently used questionnaires (Qs), with partly different layout, influence the prevalence of respiratory symptoms. Study Design and Setting A booklet containing two Qs, the Global Allergy and Asthma European Network Q and the Obstructive Lung Disease in Northern Sweden Q, was mailed to 30 000 subjects aged 16–75 years in West Sweden; 62% responded. Sixteen questions were included in the analysis: seven identical between the Qs, four different in set-up and five with the same layout but different wording. Comparisons were made using differences in proportions, observed agreement and Kappa statistics. Results Identical questions yielded similar prevalences with high observed agreement and kappa values. Questions with different set-up or differences in wording resulted in significantly different prevalences with lower observed agreement and kappa values. In general, the use of follow-up questions, excluding subjects answering no to the initial question, resulted in 2.9–6.7% units lower prevalence. Conclusion The question set-up has great influences on epidemiological results, and specifically questions that are set up to be excluded based on a previous no answer leads to lower prevalence compared with detached questions. Therefore, Q layout and exact wording of questions has to be carefully considered when comparing studies. Please cite this paper as: Ekerljung L, Rönmark E, Lötvall J, Wennergren G, Torén K and Lundbäck B. Questionnaire layout and wording influence prevalence and risk estimates of respiratory symptoms in a population cohort. Clin Respir J 2013; 7: 53–63. PMID:22243692

Prospective observational cohort study of patients with weaning failure admitted to a specialist weaning, rehabilitation and home mechanical ventilation centre

PubMed Central

Mifsud Bonnici, Denise; Sanctuary, Thomas; Murphy, Patrick B; Steier, Joerg; Marino, Philip; Pattani, Hina; Creagh-Brown, Ben C; Hart, Nicholas

2016-01-01

Objectives According to National Health Service England (NHSE) specialist respiratory commissioning specification for complex home ventilation, patients with weaning failure should be referred to a specialist centre. However, there are limited data reporting the clinical outcomes from such centres. Setting Prospective observational cohort study of patients admitted to a UK specialist weaning, rehabilitation and home mechanical ventilation centre between February 2005 and July 2013. Participants 262 patients admitted with a median age of 64.2 years (IQR 52.6–73.2 years). 59.9% were male. Results 39.7% of patients had neuromuscular and/or chest wall disease, 21% were postsurgical, 19.5% had chronic obstructive pulmonary disease (COPD), 5.3% had obesity-related respiratory failure and 14.5% had other diagnoses. 64.1% of patients were successfully weaned, with 38.2% weaned fully from ventilation, 24% weaned to nocturnal non-invasive ventilation (NIV), 1.9% weaned to nocturnal NIV with intermittent NIV during the daytime. 21.4% of patients were discharged on long-term tracheostomy ventilation. The obesity-related respiratory failure group were most likely to wean (relative risk (RR) for weaning success=1.48, 95% CI 1.35 to 1.77; p<0.001), but otherwise weaning success rates did not significantly vary by diagnostic group. The median time-to-wean was 19 days (IQR 9–33) and the median duration of stay was 31 days (IQR 16–50), with no difference observed between the groups. Weaning centre mortality was 14.5%, highest in the COPD group (RR=2.15, 95% CI 1.19 to 3.91, p=0.012) and lowest in the neuromuscular and/or chest wall disease group (RR=0.34, 95% CI 0.16 to 0.75, p=0.007). Of all patients discharged alive, survival was 71.7% at 6 months and 61.8% at 12 months postdischarge. Conclusions Following NHSE guidance, patients with weaning delay and failure should be considered for transfer to a specialist centre where available, which can demonstrate

A Phenomenological Study of an Indonesian Cohort Group's Transformative Learning

ERIC Educational Resources Information Center

Budiraharjo, Markus

2013-01-01

This study was set to investigate how a cohort of ten Indonesian teachers experienced transformations in their teaching professionalism upon receiving an assignment of instructional leadership training to other school leaders. These ten teachers, who came from three different Indonesian Jesuit high schools and one archdiocese-based educational…

Prospective Observational Study of Implantable Cardioverter‐Defibrillators in Primary Prevention of Sudden Cardiac Death: Study Design and Cohort Description

PubMed Central

Cheng, Alan; Dalal, Darshan; Butcher, Barbara; Norgard, Sanaz; Zhang, Yiyi; Dickfeld, Timm; Eldadah, Zayd A.; Ellenbogen, Kenneth A.; Guallar, Eliseo; Tomaselli, Gordon F.

2013-01-01

Background Primary‐prevention implantable cardioverter‐defibrillators (ICDs) reduce total mortality in patients with severe left ventricular systolic function. However, only a minority of patients benefit from these devices. We designed the Prospective Observational Study of Implantable Cardioverter‐Defibrillators (PROSE‐ICD) to identify risk factors and enhance our understanding of the biological mechanisms that predispose to arrhythmic death in patients undergoing ICD implantation for primary prevention of sudden death. Methods and Results This is a multicenter prospective cohort study with a target enrollment of 1200 patients. The primary end point is ICD shocks for adjudicated ventricular tachyarrhythmias. The secondary end point is total mortality. All patients undergo a comprehensive evaluation including history and physical examination, signal‐averaged electrocardiograms, and blood sampling for genomic, proteomic, and metabolomic analyses. Patients are evaluated every 6 months and after every known ICD shock for additional electrocardiographic and blood sampling. As of December 2011, a total of 1177 patients have been enrolled with more nonwhite and female patients compared to previous randomized trials. A total of 143 patients have reached the primary end point, whereas a total of 260 patients died over an average follow‐up of 59 months. The PROSE‐ICD study represents a real‐world cohort of individuals with systolic heart failure receiving primary‐prevention ICDs. Conclusions Extensive electrophysiological and structural phenotyping as well as the availability of serial DNA and serum samples will be important resources for evaluating novel metrics for risk stratification and identifying patients at risk for arrhythmic sudden death. Clinical Trial Registration URL: http://clinicaltrials.gov/ Unique Identifier: NCT00733590. PMID:23525420

Incidence of infection following internal fixation of open and closed tibia fractures in India (INFINITI): a multi-centre observational cohort study.

PubMed

Doshi, Prakash; Gopalan, Hitesh; Sprague, Sheila; Pradhan, Chetan; Kulkarni, Sunil; Bhandari, Mohit

2017-04-14

Trauma is a major public health problem, particularly in India due to the country's rapid urbanization. Tibia fractures are a common and often complicated injury that is at risk of infection following surgical fixation. The primary objectives of this cohort study were to determine the incidence of infection within one year of surgery and to describe the distribution of infections by location and time of diagnosis for tibia fractures in India. We conducted a multi-center, prospective cohort study. Patients who presented with an open or closed tibia fracture treated with internal fixation to one of the participating hospitals in India were invited to participate in the study. Participants attended follow-up visits at 3, 6, and 12 months post-surgery, where they were assessed for infections, fracture healing, and health-related quality of life as measured by the EurQol-5 Dimensions (EQ-5D). Seven hundred eighty-seven participants were included in the study and 768 participants completed the 12 month follow-up. The overall incidence of infection was 2.9% (23 infections). The incidence of infection was 1.6% (10 infections) in closed and 8.0% (13 infections) in open fractures. There were 7 deep and 16 superficial infections, with 5 being early, 7 being delayed, and 11 being late infections. Intra-operative antibiotics were given to 92.1% of participants and post-operative antibiotics were given to 96.8% of participants. Antibiotics were prescribed for an average of 8.3 days for closed fractures and 9.1 days for open fractures. Infected fractures took significantly longer to heal, and participants who had an infection had significantly lower EQ-5D scores. The incidence of infection within this cohort is similar to those seen in developed countries. The duration of prophylactic antibiotic use was longer than standard practice in North America, raising concern for the potential development of antibiotic resistant microbes within Indian orthopaedic settings. Future

Parental Separation and Cardiometabolic Risk Factors in Late Adolescence: A Cross-Cohort Comparison.

PubMed

Soares, Ana Luiza Gonçalves; Gonçalves, Helen; Matijasevich, Alicia; Sequeira, Maija; Smith, George Davey; Menezes, Ana M B; Assunção, Maria Cecília; Wehrmeister, Fernando C; Fraser, Abigail; Howe, Laura D

2017-05-15

The aim of this study was to explore the association between parental separation during childhood (up to 18 years of age) and cardiometabolic risk factors (body mass index, fat mass index, blood pressure, physical activity, smoking, and alcohol consumption) in late adolescence using a cross-cohort comparison and to explore whether associations differ according to the age at which the parental separation occurred and the presence or absence of parental conflict prior to separation. Data from the Avon Longitudinal Study of Parents and Children (ALSPAC, United Kingdom) (1991-2011) and the 1993 Pelotas Birth Cohort (Brazil) (1993-2011) were used. The associations of parental separation with children's cardiometabolic risk factors were largely null. Higher odds of daily smoking were observed in both cohorts for those adolescents whose parents separated (for ALSPAC, odds ratio = 1.46; for Pelotas Birth Cohort, odds ratio = 1.98). Some additional associations were observed in the Pelotas Birth Cohort but were generally in the opposite direction to our a priori hypothesis: Parental separation was associated with lower blood pressure and fat mass index, and with more physical activity. No consistent differences were observed when analyses were stratified by child's age at parental separation or parental conflict. © The Author 2017. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health.

Criminality and suicide: a longitudinal Swedish cohort study

PubMed Central

Stenbacka, M; Romelsjö, A; Jokinen, J

2014-01-01

Objectives This study aimed to investigate whether violent and non-violent offending were related to elevated risk of suicide. We also investigated whether the risk was higher among those with repeated offences and how experiences of substance misuse and suicide attempt modified the relationship. Design A nationwide prospective cohort study. Setting A register study of 48 834 conscripted men in 1969/1970 in Sweden followed up during a 35-year period in official registers. Participants A birth cohort of 48 834 men who were mandatory conscripted for military service in 1969/70 at the age of 18–20 years. Possible confounders were retrieved from psychological assessments at conscription and the cohort was linked to mortality and hospitalisation and crime records from 1970 onwards. Estimates of suicide risks were calculated as HR with 95% CIs using Cox proportional regression analyses with adjustment for potential confounding by family, psychological and behavioural factors including substance use and psychiatric disorders. Results Of the total cohort, 2671 (5.5%) persons died during the follow-up period. Of these, 615 (23%) persons died due to suicide. Non-violent criminality was evident for 29% and violent criminality for 4.7% of all the participants. In the crude model, the violent offenders had nearly five times higher risk (HR=4.69, 3.56 to 6.19) to die from suicide and non-violent criminals had about two times higher risk (HR=2.08, 1.72 to 2.52). In the fully adjusted model, the HRs were still significant for suicide in the non-violent group. Conclusions Experiences of violent or non-violent criminality were associated with increased risk of suicide. Comorbidity with alcohol and substance use and psychiatric disorders modified the risk, but the suicide risk remained significantly elevated for non-violent criminals. It is crucial to identify offenders and especially repeated offenders who also suffer from alcohol or substance misuse and psychiatric illness in

Safety of stavudine in the treatment of HIV infection with a special focus on resource-limited settings.

PubMed

Makinson, Alain; Moing, Vincent Le; Kouanfack, Charles; Laurent, Christian; Delaporte, Eric

2008-05-01

Western randomized trials and prospective cohorts in resource-limited settings have proven virological success with stavudine-based highly active antiretroviral therapy. However, stavudine is no longer recommended in first-line treatments in these two settings due to its intrinsic toxicities and side effects. Yet it remains a cornerstone of treatment in resource-limited settings, due to lack of alternatives and its availability in generic fixed-dose combinations. To review the toxic effects of stavudine and their prevention and management strategies, especially in resource-limited settings. Data from clinical and pharmacological trials in Western countries, as well as prospective cohorts in resource-limited settings, were reviewed. Initiating or switching to less toxic nucleoside analogues whenever possible, or lowering stavudine doses to 30 mg b.i.d., is strongly recommended.

Risk factors associated with incident sexually transmitted infections in HIV-positive patients in the Australian HIV Observational Database: a prospective cohort study.

PubMed

Mulhall, B P; Wright, S T; De La Mata, N; Allen, D; Brown, K; Dickson, B; Grotowski, M; Jackson, E; Petoumenos, K; Foster, R; Read, T; Russell, D; Smith, D J; Templeton, D J; Fairley, C K; Law, M G

2016-09-01

We established a subcohort of HIV-positive individuals from 10 sexual health clinics within the Australian HIV Observational Database (AHOD). The aim of this study was to assess demographic and other factors that might be associated with an incident sexually transmitted infection (STI). The cohort follow-up was from March 2010 to March 2013, and included patients screened at least once for an STI. We used survival methods to determine time to first new and confirmed incident STI infection (chlamydia, gonorrhoea, syphilis or genital warts). Factors evaluated included sex, age, mode of HIV exposure, year of AHOD enrolment, hepatitis B or C coinfection, time-updated CD4 cell count, time-updated HIV RNA viral load, and prior STI diagnosis. There were 110 first incident STI diagnoses observed over 1015 person-years of follow-up, a crude rate of 10.8 [95% confidence interval (CI) 9.0-13.0] per 100 person-years. Factors independently associated with increased risk of incident STI included younger age [≥ 50 vs. 30-39 years old, adjusted hazards ratio (aHR) 0.4; 95% CI 0.2-0.8; P < 0.0001]; prior STI infection (aHR 2.5; 95% CI 1.6-3.8; P < 0.001), and heterosexual vs. men who have sex with men (MSM) as the likely route of exposure (aHR 0.2; 95% CI 0.1-0.6; P < 0.001). In this cohort of individualsbeing treated with antiretroviral drugs, those who were MSM, who were 30-39 years old, and who had a prior history of STI, were at highest risk of a further STI diagnosis. © 2016 British HIV Association.

Impact of Exercise Counseling on Physical Function in Chronic Kidney Disease: An Observational Study

PubMed Central

Storsley, Leroy J.; Hiebert, Brett M.; Nelko, Serena; Cheskin, Lawrence J.; McAdams-DeMarco, Mara A.; Rigatto, Claudio

2018-01-01

Background: Individuals with chronic kidney disease (CKD) have low levels of physical activity and physical function. Although guidelines endorse exercise counseling for individuals with CKD, it is not yet part of routine care. Objective: We investigated the effect of attending a real-life exercise counseling clinic (ECC) on physical function in individuals with CKD. Design: Retrospective analysis of prospectively collected observational data with quasi-experimental design. Setting and Participants: Patients with all stages of CKD registered in a large provincial renal program were eligible. The exposed cohort who attended the ECC between January 1, 2011, and March 15, 2014, included 214 individuals. The control cohort included 292 individuals enrolled in an observational study investigating longitudinal change in frailty during the same time period. Predictor/Factor: Attendance at an ECC. Outcomes and Measurements: Change in physical function as measured by Short Physical Performance Battery (SPPB) score, physical activity level (Human Activity Profile [HAP]/Physical Activity Scale for the Elderly [PASE]), and health-related quality of life (HRQOL; EQ5D/VAS) over 1 year. Results: Eighty-seven individuals in the ECC cohort and 125 participants in the control cohort completed 1-year follow-up. Baseline median SPPB score was 10 (interquartile range [IQR]: 9-12) and 9 (IQR: 7-11) in the ECC and control cohorts, respectively (P < .01). At 1 year, SPPB scores were 10 (IQR: 8-12) and 9 (IQR: 6-11) in the ECC and control cohorts, respectively (P = .04). Mean change in SPPB over 1 year was not significantly different between groups: −0.33 (95% confidence interval [CI]: −0.81 to 0.15) in ECC and −0.22 (95% CI: −0.61 to 0.17) in control (P = .72). There was no significant difference in the proportion of individuals in each cohort with an increase/decrease in SPPB score over time. There was no significant change in physical activity or HRQOL over time between groups

Intrauterine stress and male cohort quality: the case of September 11, 2001.

PubMed

Bruckner, Tim A; Nobles, Jenna

2013-01-01

Empirical research and the theory of natural selection assert that male mortality more than female mortality responds to ambient stressors in utero. Although population stressors may adversely damage males that survive to birth, the rival culled cohort hypothesis contends that males born during stressful times may exhibit better health than males in other cohorts because fetal loss has "culled" the frailest males. We tested these hypotheses by examining child developmental outcomes in a U.S. birth cohort reportedly affected in utero by the September 11, 2001 attacks. We used as outcomes the Bayley cognitive score and child height-for-age from the Early Childhood Longitudinal Study-Birth Cohort. Previous research demonstrates a male-specific effect of 9/11 on California infants born in December 2001. We, therefore, compared cognition and height of this cohort with males born prior to the 9/11 attacks. We controlled for unobserved confounding across gender, season, and region by using triple-difference regression models (N = 6950). At 24 months, California males born in December scored greater than expected in cognitive ability (coef = 9.55, standard error = 3.37; p = 0.004). We observed no relation with height. Results remained robust to alternative specifications. Findings offer partial support for the culled cohort hypothesis in that we observed greater than expected cognitive scores at two years of age among a cohort of males affected by 9/11 in utero. Contemporary population stressors may induce male-specific culling, thereby resulting in relatively improved development among males that survive to birth. Copyright © 2012 Elsevier Ltd. All rights reserved.

Clinical outcomes and mortality before and after implementation of a pediatric sepsis protocol in a limited resource setting: A retrospective cohort study in Bangladesh

PubMed Central

Axelrod, David M.; Chisti, Mohammod J.; Kache, Saraswati

2017-01-01

Background Pediatric sepsis has a high mortality rate in limited resource settings. Sepsis protocols have been shown to be a cost-effective strategy to improve morbidity and mortality in a variety of populations and settings. At Dhaka Hospital in Bangladesh, mortality from pediatric sepsis in high-risk children previously approached 60%, which prompted the implementation of an evidenced-based protocol in 2010. The clinical effectiveness of this protocol had not been measured. We hypothesized that implementation of a pediatric sepsis protocol improved clinical outcomes, including reducing mortality and length of hospital stay. Materials and methods This was a retrospective cohort study of children 1–59 months old with a diagnosis of sepsis, severe sepsis or septic shock admitted to Dhaka Hospital from 10/25/2009-10/25/2011. The primary outcome was inpatient mortality pre- and post-protocol implementation. Secondary outcomes included fluid overload, heart failure, respiratory insufficiency, length of hospital stay, and protocol compliance, as measured by antibiotic and fluid bolus administration within 60 minutes of hospital presentation. Results 404 patients were identified by a key-word search of the electronic medical record; 328 patients with a primary diagnosis of sepsis, severe sepsis, or septic shock were included (143 pre- and185 post-protocol) in the analysis. Pre- and post-protocol mortality were similar and not statistically significant (32.17% vs. 34.59%, p = 0.72). The adjusted odds ratio (AOR) for post-protocol mortality was 1.55 (95% CI, 0.88–2.71). The odds for developing fluid overload were significantly higher post-protocol (AOR 3.45, 95% CI, 2.04–5.85), as were the odds of developing heart failure (AOR 4.52, 95% CI, 1.43–14.29) and having a longer median length of stay (AOR 1.81, 95% CI 1.10–2.96). There was no statistically significant difference in respiratory insufficiency (pre- 65.7% vs. post- 70.3%, p = 0.4) or antibiotic

Clinical outcomes and mortality before and after implementation of a pediatric sepsis protocol in a limited resource setting: A retrospective cohort study in Bangladesh.

PubMed

Kortz, Teresa Bleakly; Axelrod, David M; Chisti, Mohammod J; Kache, Saraswati

2017-01-01

Pediatric sepsis has a high mortality rate in limited resource settings. Sepsis protocols have been shown to be a cost-effective strategy to improve morbidity and mortality in a variety of populations and settings. At Dhaka Hospital in Bangladesh, mortality from pediatric sepsis in high-risk children previously approached 60%, which prompted the implementation of an evidenced-based protocol in 2010. The clinical effectiveness of this protocol had not been measured. We hypothesized that implementation of a pediatric sepsis protocol improved clinical outcomes, including reducing mortality and length of hospital stay. This was a retrospective cohort study of children 1-59 months old with a diagnosis of sepsis, severe sepsis or septic shock admitted to Dhaka Hospital from 10/25/2009-10/25/2011. The primary outcome was inpatient mortality pre- and post-protocol implementation. Secondary outcomes included fluid overload, heart failure, respiratory insufficiency, length of hospital stay, and protocol compliance, as measured by antibiotic and fluid bolus administration within 60 minutes of hospital presentation. 404 patients were identified by a key-word search of the electronic medical record; 328 patients with a primary diagnosis of sepsis, severe sepsis, or septic shock were included (143 pre- and185 post-protocol) in the analysis. Pre- and post-protocol mortality were similar and not statistically significant (32.17% vs. 34.59%, p = 0.72). The adjusted odds ratio (AOR) for post-protocol mortality was 1.55 (95% CI, 0.88-2.71). The odds for developing fluid overload were significantly higher post-protocol (AOR 3.45, 95% CI, 2.04-5.85), as were the odds of developing heart failure (AOR 4.52, 95% CI, 1.43-14.29) and having a longer median length of stay (AOR 1.81, 95% CI 1.10-2.96). There was no statistically significant difference in respiratory insufficiency (pre- 65.7% vs. post- 70.3%, p = 0.4) or antibiotic administration between the cohorts (pre- 16.08% vs. post- 12

Maternal Malaria and Malnutrition (M3) initiative, a pooled birth cohort of 13 pregnancy studies in Africa and the Western Pacific

PubMed Central

Unger, Holger W; Gutman, Julie; Briand, Valerie; Fievet, Nadine; Valea, Innocent; Tinto, Halidou; d'Alessandro, Umberto; Landis, Sarah H; Adu-Afarwuah, Seth; Dewey, Kathryn G; Ter Kuile, Feiko; Dellicour, Stephanie; Ouma, Peter; Slutsker, Laurence; Terlouw, Dianne J; Kariuki, Simon; Ayisi, John; Nahlen, Bernard; Desai, Meghna; Madanitsa, Mwayi; Kalilani-Phiri, Linda; Ashorn, Per; Maleta, Kenneth; Mueller, Ivo; Stanisic, Danielle; Schmiegelow, Christentze; Lusingu, John; Westreich, Daniel; van Eijk, Anna Maria; Meshnick, Steven; Rogerson, Stephen

2016-01-01

Purpose The Maternal Malaria and Malnutrition (M3) initiative has pooled together 13 studies with the hope of improving understanding of malaria–nutrition interactions during pregnancy and to foster collaboration between nutritionists and malariologists. Participants Data were pooled on 14 635 singleton, live birth pregnancies from women who had participated in 1 of 13 pregnancy studies. The 13 studies cover 8 countries in Africa and Papua New Guinea in the Western Pacific conducted from 1996 to 2015. Findings to date Data are available at the time of antenatal enrolment of women into their respective parent study and at delivery. The data set comprises essential data such as malaria infection status, anthropometric assessments of maternal nutritional status, presence of anaemia and birth weight, as well as additional variables such gestational age at delivery for a subset of women. Participating studies are described in detail with regard to setting and primary outcome measures, and summarised data are available from each contributing cohort. Future plans This pooled birth cohort is the largest pregnancy data set to date to permit a more definite evaluation of the impact of plausible interactions between poor nutritional status and malaria infection in pregnant women on fetal growth and gestational length. Given the current comparative lack of large pregnancy cohorts in malaria-endemic settings, compilation of suitable pregnancy cohorts is likely to provide adequate statistical power to assess malaria–nutrition interactions, and could point towards settings where such interactions are most relevant. The M3 cohort may thus help to identify pregnant women at high risk of adverse outcomes who may benefit from tailored intensive antenatal care including nutritional supplements and alternative or intensified malaria prevention regimens, and the settings in which these interventions would be most effective. PMID:28003287

The role of depression and social support in non-fatal drug overdose among a cohort of injection drug users in a Canadian setting

PubMed Central

Pabayo, Roman; Alcantara, Carmela; Kawachi, Ichiro; Wood, Evan; Kerr, Thomas

2013-01-01

Objectives Non-fatal overdose remains a significant source of morbidity among people who inject drugs (IDU). Although depression and social support are important in shaping the health of IDU, little is known about the relationship between these factors and overdose. Therefore, we sought to determine whether depressive symptoms and social support predicted non-fatal overdose among IDU in a Canadian setting. Methods Data were derived from three prospective cohorts of people who use drugs: the Vancouver Injection Drug Users Study (VIDUS), the ACCESS Cohort, and the At-Risk Youth Study (ARYS). Multilevel modeling was used to determine if depression and social support were significant predictors of non-fatal overdose across time. Analyses were stratified by sex. Results There were 1,931 participants included in this analysis, including 653 (33.8%) females and 69 (3.6%) youth 20 years old or younger. Depressed men (Adjusted odds ratio [AOR] =1.53, 95% confidence intervals [CI] =1.25, 1.87) and women (Adjusted odds ratio [AOR] =2.23, 95% confidence intervals [CI] =1.65, 3.00) were more likely to experience a non-fatal overdose. Further, among women, those who reported having 3 or more persons they could rely upon for social support were less likely to experience a non-fatal overdose (AOR=0.54, 95% 0.31, 0.93). Conclusion Although depression was a significant predictor of non-fatal drug overdose, social support was a significant predictor among women only. Possible strategies to prevent non-fatal overdose may include identifying IDU experiencing severe depressive symptoms and providing targeted mental health treatments and mobilizing interpersonal social support among IDU, especially among women. PMID:23647731

Dementia and vagotomy in Taiwan: a population-based cohort study

PubMed Central

Lin, Shih-Yi; Lin, Cheng-Li; Wang, I-Kuan; Lin, Cheng-Chieh; Lin, Chih-Hsueh; Hsu, Wu-Huei

2018-01-01

Objective Truncal vagotomy is associated with a decreased risk of subsequent Parkinson disease (PD), although the effect of vagotomy on dementia is unclear. In response, we investigated the risk of dementia in patients who underwent vagotomy. Setting Population-based cohort study. Participants A total of 155 944 patients who underwent vagotomy (vagotomy cohort) and 155 944 age-matched, sex-matched and comorbidity-matched controls (non-vagotomy cohort) were identified between 2000 and 2011. Primary and secondary outcome measures All patient data were tracked until the diagnosis of dementia, death or the end of 2011. The cumulative incidence of subsequent dementia and HRs were calculated. Results The mean ages of the study patients in the vagotomy and non-vagotomy cohorts were 56.6±17.4 and 56.7±17.3 years, respectively. The overall incidence density rate for dementia was similar in the vagotomy and non-vagotomy cohorts (2.43 and 2.84 per 1000 person-years, respectively). After adjustment for age, sex and comorbidities such as diabetes, hypertension, hyperlipidaemia, stroke, depression, coronary artery disease and PD, the patients in the vagotomy cohort were determined to not be at a higher risk of dementia than those in the non-vagotomy cohort (adjusted HR=1.09, 95% CI 0.87 to 1.36). Moreover, the patients who underwent truncal vagotomy were not associated with risk of dementia (adjusted HR=1.04, 95% CI 0.87 to 1.25), compared with the patients who did not undergo vagotomy. Conclusion Vagotomy, either truncal or selective, is not associated with risk of dementia. PMID:29602843

Effects of high CD4 cell counts on death and attrition among HIV patients receiving antiretroviral treatment: an observational cohort study.

PubMed

Tang, Zhenzhu; Pan, Stephen W; Ruan, Yuhua; Liu, Xuanhua; Su, Jinming; Zhu, Qiuying; Shen, Zhiyong; Zhang, Heng; Chen, Yi; Lan, Guanghua; Xing, Hui; Liao, Lingjie; Feng, Yi; Shao, Yiming

2017-06-09

Current WHO guidelines recommend initiating ART regardless of CD4+ cell count. In response, we conducted an observational cohort study to assess the effects of pre-ART CD4+ cell count levels on death, attrition, and death or attrition in HIV treated patients. This large HIV treatment cohort study (n = 49,155) from 2010 to 2015 was conducted in Guangxi, China. We used a Cox regression model to analyze associations between pre-ART CD4+ cell counts and death, attrition, and death or attrition. The average mortality and ART attrition rates among all treated patients were 2.63 deaths and 5.32 attritions per 100 person-years, respectively. Compared to HIV patients with <350 CD4+ cells/mm 3 at ART initiation, HIV patients with >500 CD4+ cells/mm 3 at ART initiation had a significantly lower mortality rate (Adjusted hazard ratio: 0.56, 95% CI: 0.40-0.79), but significantly higher ART attrition rate (AHR: 1.17, 95% CI: 1.03-1.33). Results from this study suggest that HIV patients with high CD4+ cell counts at the time of ART initiation may be at greater risk of treatment attrition. To further reduce ART attrition, it is imperative that patient education and healthcare provider training on ART adherence be enhanced and account for CD4 levels at ART initiation.

German-wide prospective DACAPO cohort of survivors of the acute respiratory distress syndrome (ARDS): a cohort profile.

PubMed

Dodoo-Schittko, Frank; Brandstetter, Susanne; Brandl, Magdalena; Blecha, Sebastian; Quintel, Michael; Weber-Carstens, Steffen; Kluge, Stefan; Kirschning, Thomas; Muders, Thomas; Bercker, Sven; Ellger, Björn; Arndt, Christian; Meybohm, Patrick; Adamzik, Michael; Goldmann, Anton; Karagiannidis, Christian; Bein, Thomas; Apfelbacher, Christian

2018-04-04

While most research focuses on the association between medical characteristics and residual morbidity of survivors of the acute respiratory distress syndrome (ARDS), little is known about the relation between potentially modifiable intensive care unit (ICU) features and the course of health-related quality of life (HRQoL). Accordingly, the DACAPO study was set up to elucidate the influence of quality of intensive care on HRQoL and return to work (RtW) in survivors of ARDS. The continued follow-up of these former ICU patients leads to the establishment of the DACAPO (survivor) cohort. Sixty-one ICUs all over Germany recruited patients with ARDS between September 2014 and April 2016. Inclusion criteria were: (1) age older than 18 years and (2) ARDS diagnosis according to the 'Berlin definition'. No further inclusion or exclusion criteria were applied. 1225 patients with ARDS could be included in the DACAPO ICU sample. Subsequently, the 876 survivors at ICU discharge form the actual DACAPO cohort. The recruitment of the participants of the DACAPO cohort and the baseline data collection has been completed. The care-related data of the DACAPO cohort reveal a high proportion of adverse events (in particular, hypoglycaemia and reintubation). However, evidence-based supportive measures were applied frequently. Three months, 6 months and 1 year after ICU admission a follow-up assessment is conducted. The instruments of the follow-up questionnaires comprise the domains: (A) HRQoL, (B) RtW, (C) general disability, (D) psychiatric symptoms and (E) social support. Additionally, an annual follow-up of the DACAPO cohort focusing on HRQoL, psychiatric symptoms and healthcare utilisation will be conducted. Furthermore, several add-on projects affecting medical issues are envisaged. NCT02637011. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly

How are European birth-cohort studies engaging and consulting with young cohort members?

PubMed

Lucas, Patricia J; Allnock, Debra; Jessiman, Tricia

2013-04-11

Birth cohort studies, where parents consent for their child to be enrolled in a longitudinal study prior to or soon after birth, are a powerful study design in epidemiology and developmental research. Participation often continues into adulthood. Where participants are enrolled as infants, provision should be made for consent, consultation and involvement in study design as they age. This study aims to audit and describe the extent and types of consultation and engagement currently used in birth cohorts in Europe. Seventy study groups (representing 84 cohorts) were contacted to ask about their practice in engaging and involving study members. Information was gathered from study websites and publications, 15 cohorts provided additional information via email and 17 cohorts were interviewed over the phone. The cohorts identified confirm the growth of this study design, with more than half beginning since 1990, and 4 since 2011. Most studies maintain a website open to the general public, although many are written for the scientific community only. Five studies have web pages specifically for young cohort members and one study provides a dedicated page for fathers. Cohorts send newsletters, cards, and summaries of findings to participants to stay in touch. Six cohorts use Facebook for this purpose. Five cohorts provide feedback opportunities for participants after completing a round of data collection. We know of just 8 cohorts who have a mechanism for consulting with parents and 3 a mechanism for consulting with young people themselves, although these were 'one off' consultations for some groups. Barriers to further consultation with cohort members were: concerns about impact on quality of research, ethical constraints, resource limitations, lack of importance, and previous adverse experiences. Although the children in some of the cohorts are still young (born in the last 10 years) many are old enough to include some element of consultation. Barriers to greater

Birth cohorts in Asia: The importance, advantages, and disadvantages of different-sized cohorts.

PubMed

Kishi, Reiko; Araki, Atsuko; Minatoya, Machiko; Itoh, Sachiko; Goudarzi, Houman; Miyashita, Chihiro

2018-02-15

Asia contains half of the world's children, and the countries of Asia are the most rapidly industrializing nations on the globe. Environmental threats to the health of children in Asia are myriad. Several birth cohorts were started in Asia in early 2000, and currently more than 30 cohorts in 13 countries have been established for study. Cohorts can contain from approximately 100-200 to 20,000-30,000 participants. Furthermore, national cohorts targeting over 100,000 participants have been launched in Japan and Korea. The aim of this manuscript is to discuss the importance of Asian cohorts, and the advantages and disadvantages of different-sized cohorts. As for case, one small-sized (n=514) cohort indicate that even relatively low level exposure to dioxin in utero could alter birth size, neurodevelopment, and immune and hormonal functions. Several Asian cohorts focus prenatal exposure to perfluoroalkyo substances and reported associations with birth size, thyroid hormone levels, allergies and neurodevelopment. Inconsistent findings may possibly be explained by the differences in exposure levels and target chemicals, and by possible statistical errors. In a smaller cohort, novel hypotheses or preliminary examinations are more easily verifiable. In larger cohorts, the etiology of rare diseases, such as birth defects, can be analyzed; however, they require a large cost and significant human resources. Therefore, conducting studies in only one large cohort may not always be the best strategy. International collaborations, such as the Birth Cohort Consortium of Asia, would cover the inherent limitation of sample size in addition to heterogeneity of exposure, ethnicity, and socioeconomic conditions. Copyright © 2017 Elsevier B.V. All rights reserved.

Cohort Profile Update: The China Jintan Child Cohort Study

PubMed Central

Liu, Jianghong; Cao, Siyuan; Chen, Zehang; Raine, Adrian; Hanlon, Alexandra; Ai, Yuexian; Zhou, Guoping; Yan, Chonghuai; Leung, Patrick W; McCauley, Linda; Pinto-Martin, Jennifer

2015-01-01

The China Jintan Child Cohort study began in 2004 with 1656 pre-school participants and a research focus on studying the impact of environmental exposures, such as lead, on children’s neurobehavioural outcomes. This population cohort now includes around 1000 of the original participants, who have been assessed three times over a period of 10 years. Since the original IJE cohort profile publication in 2010, participants have experienced a critical developmental transition from pre-school to school age and then adolescence. The study has also witnessed an increase in breadth and depth of data collection from the original aim of risk assessment. This cohort has added new directions to investigate the mechanisms and protective factors for the relationship between early health factors and child physical and mental health outcomes, with an emphasis on neurobehavioural consequences. The study now encompasses 11 domains, composed of repeated measures of the original variables and new domains of biomarkers, sleep, psychophysiology, neurocognition, personality, peer relationship, mindfulness and family dynamics. Depth of evaluation has increased from parent/teacher report to self/peer report and intergenerational family report. Consequently, the cohort has additional directions to include: (i) classmates of the original cohort participants for peer relationship assessment; and (ii) parental and grandparental measures to assess personality and dynamics within families. We welcome interest in our study and ask investigators to contact the corresponding author for additional information on data acquisition. PMID:26323725

Integrating the nursing management minimum data set into the logical observation identifier names and codes system.

PubMed

Subramanian, Amarnath; Westra, Bonnie; Matney, Susan; Wilson, Patricia S; Delaney, Connie W; Huff, Stan; Huff, Stanley M; Huber, Diane

2008-11-06

This poster describes the process used to integrate the Nursing Management Minimum Data Set (NMMDS), an instrument to measure the nursing context of care, into the Logical Observation Identifier Names and Codes (LOINC) system to facilitate contextualization of quality measures. Integration of the first three of 18 elements resulted in 48 new codes including five panels. The LOINC Clinical Committee has approved the presented mapping for their next release.

The Classroom Observation Schedule to Measure Intentional Communication (COSMIC): an observational measure of the intentional communication of children with autism in an unstructured classroom setting.

PubMed

Pasco, Greg; Gordon, Rosanna K; Howlin, Patricia; Charman, Tony

2008-11-01

The Classroom Observation Schedule to Measure Intentional Communication (COSMIC) was devised to provide ecologically valid outcome measures for a communication-focused intervention trial. Ninety-one children with autism spectrum disorder aged 6 years 10 months (SD 16 months) were videoed during their everyday snack, teaching and free play activities. Inter-rater reliability was high and relevant items showed significant associations with comparable items from concurrent Autism Diagnostic Observation Schedule-Generic (Lord et al. 2000, J Autism Dev Disord 30(3):205-223) assessments. In a subsample of 28 children initial differences in rates of initiations, initiated speech/vocalisation and commenting were predictive of language and communication competence 15 months later. Results suggest that the use of observational measures of intentional communication in natural settings is a valuable assessment strategy for research and clinical practice.

A Study of Group Dynamics in Educational Leadership Cohort and Non-Cohort Groups

ERIC Educational Resources Information Center

Greenlee, Bobbie J.; Karanxha, Zorka

2010-01-01

The purpose of this study was to examine group dynamics of educational leadership students in cohorts and make comparisons with the group dynamics characteristics of non-cohort students. Cohorts have emerged as dynamic and adaptive entities with attendant group dynamic processes that shape collective learning and action. Cohort (n=42) and…

Age, period and cohort effects on suicide mortality in Russia, 1956-2005.

PubMed

Jukkala, Tanya; Stickley, Andrew; Mäkinen, Ilkka Henrik; Baburin, Aleksei; Sparén, Pär

2017-03-07

Russian suicide mortality rates changed rapidly over the second half of the twentieth century. This study attempts to differentiate between underlying period and cohort effects in relation to the changes in suicide mortality in Russia between 1956 and 2005. Sex- and age-specific suicide mortality data were analyzed using an age-period-cohort (APC) approach. Descriptive analyses and APC modeling with log-linear Poisson regression were performed. Strong period effects were observed for the years during and after Gorbachev's political reforms (including the anti-alcohol campaign) and for those following the break-up of the Soviet Union. After mutual adjustment, the cohort- and period-specific relative risk estimates for suicide revealed differing underlying processes. While the estimated period effects had an overall positive trend, cohort-specific developments indicated a positive trend for the male cohorts born between 1891 and 1931 and for the female cohorts born between 1891 and 1911, but a negative trend for subsequent cohorts. Our results indicate that the specific life experiences of cohorts may be important for variations in suicide mortality across time, in addition to more immediate effects of changes in the social environment.

Quasi-Experiments in Schools: The Case for Historical Cohort Control Groups

ERIC Educational Resources Information Center

Walser, Tamara M.

2014-01-01

There is increased emphasis on using experimental and quasi-experimental methods to evaluate educational programs; however, educational evaluators and school leaders are often faced with challenges when implementing such designs in educational settings. Use of a historical cohort control group design provides a viable option for conducting…

Conflict Resolution and Children's Behaviour: Observing and Understanding Social and Cooperative Play in Early Years Educational Settings

ERIC Educational Resources Information Center

Broadhead, Pat

2009-01-01

This paper draws from continuing research into the growth of sociability and cooperation in young children. It began in the mid-1980s and has continued periodically in a range of early years educational settings across the 3-6 age range. The research has underpinned the development of an observational tool. This tool--the Social Play Continuum or…

Cohort profile: the Spanish WORKing life Social Security (WORKss) cohort study

PubMed Central

López Gómez, María Andrée; Durán, Xavier; Zaballa, Elena; Sanchez-Niubo, Albert; Delclos, George L; Benavides, Fernando G

2016-01-01

Purpose The global economy is changing the labour market and social protection systems in Europe. The effect of both changes on health needs to be monitored in view of an ageing population and the resulting increase in prevalence of chronic health conditions. The Spanish WORKing life Social Security (WORKss) cohort study provides unique longitudinal data to study the impact of labour trajectories and employment conditions on health, in terms of sickness absence, permanent disability and death. Participants The WORKss cohort originated from the Continuous Working Life Sample (CWLS) generated by the General Directorate for the Organization of the Social Security in Spain. The CWLS contains a 4% representative sample of all individuals in contact with the Social Security system. The WORKss cohort exclusively includes individuals with a labour trajectory from 1981 or later. In 2004, the cohort was initiated with 1 022 779 Social Security members: 840 770 (82.2%) contributors and 182 009 (17.8%) beneficiaries aged 16 and older. Findings to date The WORKss cohort includes demographic characteristics, chronological data about employment history, retirement, permanent disability and death. These data make possible the measurement of incidence of permanent disability, the number of potential years of working life lost, and the number of contracts and inactive periods with the Social Security system. The WORKss cohort was linked to temporary sickness absence registries to study medical diagnoses that lead to permanent disability and consequently to an earlier exit from the labour market in unhealthy conditions. Future plans Thanks to its administrative source, the WORKss cohort study will continue follow-up in the coming years, keeping the representativeness of the Spanish population affiliated to the Social Security system. The linkage between the WORKss cohort and temporary sickness absence registries is envisioned to continue. Future plans include the linkage of

Management of cardiovascular risk factors with pioglitazone combination therapies in type 2 diabetes: an observational cohort study

PubMed Central

2011-01-01

Background Type 2 diabetes (T2D) is strongly associated with cardiovascular risk and requires medications that improve glycemic control and other cardiovascular risk factors. The authors aimed to assess the relative effectiveness of pioglitazone (Pio), metformin (Met) and any sulfonylurea (SU) combinations in non-insulin-treated T2D patients who were failing previous hypoglycemic therapy. Methods Over a 1-year period, two multicenter, open-labeled, controlled, 1-year, prospective, observational studies evaluated patients with T2D (n = 4585) from routine clinical practice in Spain and Greece with the same protocol. Patients were eligible if they had been prescribed Pio + SU, Pio + Met or SU + Met serving as a control cohort, once they had failed with previous therapy. Anthropometric measurements, lipid and glycemic profiles, blood pressure, and the proportions of patients at microvascular and macrovascular risk were assessed. Results All study treatment combinations rendered progressive 6-month and 12-month lipid, glycemic, and blood pressure improvements. Pio combinations, especially Pio + Met, were associated with increases in HDL-cholesterol and decreases in triglycerides and in the atherogenic index of plasma. The proportion of patients at high risk decreased after 12 months in all study cohorts. Minor weight changes (gain or loss) and no treatment-related fractures occurred during the study. The safety profile was good and proved similar among treatments, except for more hypoglycemic episodes in patients receiving SU and for the occurrence of edema in patients using Pio combinations. Serious cardiovascular events were rarely reported. Conclusions In patients with T2D failing prior hypoglycemic therapies, Pio combinations with SU or Met (especially Pio + Met) improved blood lipid and glycemic profiles, decreasing the proportion of patients with a high microvascular or macrovascular risk. The combination of Pio with SU or Met may therefore be recommended for T2D

Set-up and pilot of a population cohort for the study of the natural history of COPD and OSA: the PULSAIB study.

PubMed

Soriano, Joan B; Yáñez, Aina; Renom, Feliu; de la Peña, Mónica; Gómez, Amalia; Duro, Rosa; Uréndez, Ana; Román, Miguel

2010-06-01

We describe the set-up of a population-based study focussed on respiratory conditions, and describe a pilot study - the PULmons SAns Illes Balears (PULSAIB) study - aimed at investigating the natural history of COPD, obstructive sleep apnoea (OSA), and other common chronic diseases. A cross-sectional study was designed to survey two fieldwork areas, one rural and one urban, in the Balearic Islands, Spain. Tests conducted included a questionnaire, spirometry with post-bronchodilator (PBD) test, and portable respiratory polygraphy. We assessed all processes and tools to be used, and piloted them in 175 participants from Bunyola (rural) and 130 participants from the Son Pizà area (urban). Within this first cross-sectional assessment of the Balearic population aged 30 to 80 years, we report the prevalence of airflow limitation defined as a PBD FEV1/FVC ratio <0.7 and the prevalence of OSA defined as an apnoea-hypopnoea index (AHI) >10/hour. A cohort study in the Balearic population to investigate the natural history of COPD and OSA is feasible.

Long-term mortality after community-acquired pneumonia—impacts of diabetes and newly discovered hyperglycaemia: a prospective, observational cohort study

PubMed Central

Koskela, Heikki O; Salonen, Päivi H; Romppanen, Jarkko; Niskanen, Leo

2014-01-01

Objectives Community-acquired pneumonia is associated with a significant long-term mortality after initial recovery. It has been acknowledged that additional research is urgently needed to examine the contributors to this long-term mortality. The objective of the present study was to assess whether diabetes or newly discovered hyperglycaemia during pneumonia affects long-term mortality. Design A prospective, observational cohort study. Setting A single secondary centre in eastern Finland. Participants 153 consecutive hospitalised patients who survived at least 30 days after mild-to-moderate community-acquired pneumonia. Interventions Plasma glucose levels were recorded seven times during the first day on the ward. Several possible confounders were also recorded. The surveillance status and causes of death were recorded after median of 5 years and 11 months. Results In multivariate Cox regression analysis, a previous diagnosis of diabetes among the whole population (adjusted HR 2.84 (1.35–5.99)) and new postprandial hyperglycaemia among the non-diabetic population (adjusted HR 2.56 (1.04–6.32)) showed independent associations with late mortality. New fasting hyperglycaemia was not an independent predictor. The mortality rates at the end of follow-up were 54%, 37% and 10% among patients with diabetes, patients without diabetes with new postprandial hyperglycaemia and patients without diabetes without postprandial hyperglycaemia, respectively (p<0.001). The underlying causes of death roughly mirrored those in the Finnish general population with a slight excess in mortality due to chronic respiratory diseases. Pneumonia was the immediate cause of death in just 8% of all late deaths. Conclusions A previous diagnosis of diabetes and newly discovered postprandial hyperglycaemia increase the risk of death for several years after community-acquired pneumonia. As the knowledge about patient subgroups with an increased late mortality risk is gradually gathering

Insulin detemir improves glycemic control and reduces hypoglycemia in children with type 1 diabetes: findings from the Turkish cohort of the PREDICTIVE observational study.

PubMed

Kurtoglu, Selim; Atabek, Mehmet Emre; Dizdarer, Ceyhun; Pirgon, Ozgur; Isguven, Pinar; Emek, Sevil

2009-09-01

Insulin detemir is a basal insulin analog designed to produce a superior pharmacokinetic profile to basal formulations of human insulin. It has shown consistently improved tolerability in comparison to neutral protamine Hagedorn (NPH) insulin in adult cohorts, but there are relatively few publications involving pediatric cohorts. The efficacy and safety of insulin detemir in children with type 1 diabetes was assessed using data from the Turkish cohort of PREDICTIVE (a large, multinational, observational) study. The children investigated were using basal-bolus therapy involving NPH insulin or insulin glargine at baseline but were switched to insulin detemir as part of routine clinical care by their physicians. Twelve weeks of treatment with insulin detemir significantly reduced mean hemoglobin A1c (9.7-8.9%, p < 0.001) and mean fasting glucose [185-162 mg/dL (10.3-9 mmol/L), p < 0.01]. Fasting glucose variability was also lower after treatment with insulin detemir than previously (on either NPH or glargine, p < 0.05). The frequencies of total, major and nocturnal hypoglycemic events were significantly reduced with insulin detemir relative to baseline, with an estimated mean of 6.89 fewer events/patient/yr overall (p < 0.001) and 2.6 fewer nocturnal events/patient/yr (p < 0.01). Weight and insulin dose remained relatively unchanged. Twelve weeks of treatment with insulin detemir improved glycemic control and reduced hypoglycemia in children with type 1 diabetes. This improved tolerability might allow further dose titration and therefore additional improvements in glucose control.

The Milieu Manager: A Nursing Staffing Strategy to Reduce Observer Use in the Acute Psychiatric Inpatient Setting.

PubMed

Triplett, Patrick; Dearholt, Sandra; Cooper, Mary; Herzke, John; Johnson, Erin; Parks, Joyce; Sullivan, Patricia; Taylor, Karin F; Rohde, Judith

Rising acuity levels in inpatient settings have led to growing reliance on observers and increased the cost of care. Minimizing use of observers, maintaining quality and safety of care, and improving bed access, without increasing cost. Nursing staff on two inpatient psychiatric units at an academic medical center pilot-tested the use of a "milieu manager" to address rising patient acuity and growing reliance on observers. Nursing cost, occupancy, discharge volume, unit closures, observer expense, and incremental nursing costs were tracked. Staff satisfaction and reported patient behavioral/safety events were assessed. The pilot initiatives ran for 8 months. Unit/bed closures fell to zero on both units. Occupancy, patient days, and discharges increased. Incremental nursing cost was offset by reduction in observer expense and by revenue from increases in occupancy and patient days. Staff work satisfaction improved and measures of patient safety were unchanged. The intervention was effective in reducing observation expense and improved occupancy and patient days while maintaining patient safety, representing a cost-effective and safe approach for management of acuity on inpatient psychiatric units.

Recruitment of Hispanics into an observational study of chronic kidney disease: the Hispanic Chronic Renal Insufficiency Cohort Study experience.

PubMed

Lora, Claudia M; Ricardo, Ana C; Brecklin, Carolyn S; Fischer, Michael J; Rosman, Robert T; Carmona, Eunice; Lopez, Amada; Balaram, Manjunath; Nessel, Lisa; Tao, Kaixiang Kelvin; Xie, Dawei; Kusek, John W; Go, Alan S; Lash, James P

2012-11-01

Despite the large burden of chronic kidney disease (CKD) in Hispanics, this population has been underrepresented in research studies. We describe the recruitment strategies employed by the Hispanic Chronic Renal Insufficiency Cohort Study, which led to the successful enrollment of a large population of Hispanic adults with CKD into a prospective observational cohort study. Recruitment efforts by bilingual staff focused on community clinics with Hispanic providers in high-density Hispanic neighborhoods in Chicago, academic medical centers, and private nephrology practices. Methods of publicizing the study included church meetings, local Hispanic print media, Spanish television and radio stations, and local health fairs. From October 2005 to July 2008, we recruited 327 Hispanics aged 21-74 years with mild-to-moderate CKD as determined by age-specific estimated glomerular filtration rate (eGFR). Of 716 individuals completing a screening visit, 49% did not meet eGFR inclusion criteria and 46% completed a baseline visit. The mean age at enrollment was 57.1 and 67.1% of participants were male. Approximately 75% of enrolled individuals were Mexican American, 15% Puerto Rican, and 10% had other Latin American ancestry. Eighty two percent of participants were Spanish-speakers. Community-based and academic primary care clinics yielded the highest percentage of participants screened (45.9% and 22.4%) and enrolled (38.2% and 24.5%). However, academic and community-based specialty clinics achieved the highest enrollment yield from individuals screened (61.9% to 71.4%). A strategy focused on primary care and nephrology clinics and the use of bilingual recruiters allowed us to overcome barriers to the recruitment of Hispanics with CKD. Copyright © 2012 Elsevier Inc. All rights reserved.

A new CM SAF Solar Surface Radiation Climate Data Set derived from Meteosat Satellite Observations

NASA Astrophysics Data System (ADS)

Trentmann, J.; Mueller, R. W.; Pfeifroth, U.; Träger-Chatterjee, C.; Cremer, R.

2014-12-01

The incoming surface solar radiation has been defined as an essential climate variable by GCOS. It is mandatory to monitor this part of the earth's energy balance, and thus gain insights on the state and variability of the climate system. In addition, data sets of the surface solar radiation have received increased attention over the recent years as an important source of information for the planning of solar energy applications. The EUMETSAT Satellite Application Facility on Climate Monitoring (CM SAF) is deriving surface solar radiation from geostationary and polar-orbiting satellite instruments. While CM SAF is focusing on the generation of high-quality long-term climate data records, also operationally data is provided in short time latency within 8 weeks. Here we present SARAH (Solar Surface Radiation Dataset - Heliosat), i.e. the new CM SAF Solar Surface Radiation data set based on Meteosat satellite observations. SARAH provides instantaneous, daily- and monthly-averaged data of the effective cloud albedo (CAL), the direct normalized solar radiation (DNI) and the solar irradiance (SIS) from 1983 to 2013 for the full view of the Meteosat satellite (i.e, Europe, Africa, parts of South America, and the Atlantic ocean). The data sets are generated with a high spatial resolution of 0.05 deg allowing for detailed regional studies, and are available in netcdf-format at no cost without restrictions at www.cmsaf.eu. We provide an overview of the data sets, including a validation against reference measurements from the BSRN and GEBA surface station networks.

Higher serum levels of vitamin D at diagnosis are associated with better survival in a prospective cohort of 1,666 women with breast cancer: A case-cohort analysis in the Pathways Study

PubMed Central

Yao, Song; Kwan, Marilyn L.; Ergas, Isaac J.; Roh, Janise M.; Cheng, Ting-Yuan David; Hong, Chi-Chen; McCann, Susan E.; Tang, Li; Davis, Warren; Liu, Song; Quesenberry, Charles P.; Lee, Marion M.; Ambrosone, Christine B.; Kushi, Lawrence H.

2017-01-01

Importance There are long-standing interests in the potential benefits of vitamin D for preventing breast cancer recurrence and mortality; yet data from prospective cohort studies are limited. Objective We investigated a serum biomarker of vitamin D status, 25-hydroxyvitamin D (25OHD) measured at the time of breast cancer diagnosis, with prognosis. Design The Pathways Study is a prospective cohort study of breast cancer survivors established in 2006. Enrollment was completed in 2013; follow up is ongoing. Setting The cohort was established in Kaiser Permanente Northern California (KPNC), a large integrated healthcare delivery system in San Francisco Bay Area and central valley, California. Participants Women diagnosed with incident invasive breast cancer were typically consented and enrolled within 2 months of diagnosis. The overall enrollment rate was 46%. Participants are followed for health outcomes and comorbidities at 12, 24, 48, 72 and 96 months after baseline interview. A case-cohort design was used for efficiency assay of 25OHD, selecting 1,666 cohort members with serum samples and ensuring representation in the sub-cohort of races and clinical subtypes. Main Outcome Measures Primary outcomes are breast cancer recurrence, second primary cancer (SPC), and death. Results Serum 25OHD concentrations were lower in women with advanced stage tumors, and the lowest in premenopausal women with triple-negative cancer. Levels were also inversely associated with hazards of disease progression and death. Compared with the lowest tertile (T1), women with the highest (T3) 25OHD levels had superior overall survival (OS). This association remained after adjustment for clinical prognostic factors [hazards ratio (HR)=0.72, 95% confidence interval (CI): 0.54, 0.98]. Among premenopausal women, the association with OS was stronger, and there were also associations with breast cancer-specific survival (BCSS) and invasive disease-free survival (IDFS) (OS: HR=0.45, 95% CI, 0.21–0

Analysis of the North Carolina long-term care polypharmacy initiative: a multiple-cohort approach using propensity-score matching for both evaluation and targeting.

PubMed

Trygstad, Troy K; Christensen, Dale B; Wegner, Steve E; Sullivan, Rob; Garmise, Jennifer M

2009-09-01

The high cost and undesirable consequences of polypharmacy are well-recognized problems among elderly long-term care (LTC) residents. Despite the implementation of the 1987 Omnibus Budget Reconciliation Act, which requires pharmacist review of drug regimens in this setting, medical and drug costs for LTC residents have continued to increase. This study evaluates the North Carolina Long-Term Care Polypharmacy Initiative, a large-scale medication therapy management program (MTMP) that combined drug utilization review activities with drug regimen review techniques. This was a prospective records-based study that used a difference-in-difference model with both historical and nonintervention group controls. To ensure equivalence among subjects, propensity scoring was used to match study subjects from participating LTC facilities with comparison subjects from nonparticipating facilities. Residents with interventions were grouped for analysis by intervention type-retrospective only, prospective only, or dual type (residents with both prospective and retrospective interventions)-and by intervention stage-review, recommendation, and drug change-plus an all-inclusive "all types" grouping that aggregated groups by intervention type, for a total of 10 total cohorts. In the overall population of 5255 study subjects identified, a US $21.63 per member per month drug-cost savings was observed. Although only 1 of 10 cohorts had a change in the number of drug fills, substantial reductions in 2 of 5 types of drug alerts were observed in all 10 cohorts. A reduction in the relative risk for hospitalization (0.84 [95% CI, 0.71-1.00]) was observed in the cohort of residents receiving a retrospective review. This Initiative suggests that an MTMP can be quickly launched in a large number of LTC facility residents to produce monetary drug-cost savings and improved health outcomes. Additionally, the evaluation of this program illustrates the utility of using propensity scoring techniques to

The Home Observation of Periconceptional Exposures (HOPE) study, a prospective cohort: aims, design, recruitment and compliance.

PubMed

Porucznik, Christina A; Cox, Kyley J; Schliep, Karen C; Wilkins, Diana G; Stanford, Joseph B

2016-06-08

To examine transient environmental exposures and their relationship with human fecundity, exposure assessment should occur optimally at the time of conception in both members of the couple. We performed an observational, prospective cohort study with biomonitoring in both members of a heterosexual couple trying to conceive. Couples collected urine, saliva, and semen specimens for up to two menstrual cycles on days corresponding to the time windows of fertilization, implantation, and early pregnancy, identified based on the woman's observations of her cervical fluid. Three hundred nine eligible couples were screened between 2011 and 2015, of which 183 enrolled. Eleven couples (6.0 %) withdrew or were lost to follow up. The most successful and cost effective recruiting strategies were word of mouth (40 % of participating couples), posters and flyers (37 %), and targeted Facebook advertising (13 %) with an overall investment of $37.35 spent on recruitment per couple. Both men and women collected ≥97.2 % of requested saliva samples, and men collected ≥89.9 % of requested semen samples. Within the periovulatory days (±3 days), there was at least one urine specimen collected by women in 97.1 % of cycles, and at least one by men in 91.7 % of cycles. Daily compliance with periovulatory urine specimens ranged from 66.5 to 92.4 % for women and from 55.7 to 75.0 % for men. Compliance was ≥88 % for questionnaire completion at specified time points. Couples planning to conceive can be recruited successfully for periconceptional monitoring, and will comply with intensive study protocols involving home collection of biospecimens and questionnaire data.

Structure and Correlates of Cognitive Aging in a Narrow Age Cohort

PubMed Central

2014-01-01

Aging-related changes occur for multiple domains of cognitive functioning. An accumulating body of research indicates that, rather than representing statistically independent phenomena, aging-related cognitive changes are moderately to strongly correlated across domains. However, previous studies have typically been conducted in age-heterogeneous samples over longitudinal time lags of 6 or more years, and have failed to consider whether results are robust to a comprehensive set of controls. Capitalizing on 3-year longitudinal data from the Lothian Birth Cohort of 1936, we took a longitudinal narrow age cohort approach to examine cross-domain cognitive change interrelations from ages 70 to 73 years. We fit multivariate latent difference score models to factors representing visuospatial ability, processing speed, memory, and crystallized ability. Changes were moderately interrelated, with a general factor of change accounting for 47% of the variance in changes across domains. Change interrelations persisted at close to full strength after controlling for a comprehensive set of demographic, physical, and medical factors including educational attainment, childhood intelligence, physical function, APOE genotype, smoking status, diagnosis of hypertension, diagnosis of cardiovascular disease, and diagnosis of diabetes. Thus, the positive manifold of aging-related cognitive changes is highly robust in that it can be detected in a narrow age cohort followed over a relatively brief longitudinal period, and persists even after controlling for many potential confounders. PMID:24955992

SSRIs and risk of suicide attempts in young people - A Danish observational register-based historical cohort study, using propensity score.

PubMed

Christiansen, Erik; Agerbo, Esben; Bilenberg, Niels; Stenager, Elsebeth

2016-01-01

SSRIs are widely used in the treatment of mental illness for both children and adults. Studies have found a slightly increased risk of suicidal thoughts and suicide attempts in young people using SSRIs but SSRIs' impact on risk for suicides in youth is not well-established. Is there indication that SSRIs might raise risk for suicide attempts in young people? We used an observational register-based historical cohort design, a large cohort of all Danish individuals born in 1983-1989 (n = 392,458) and a propensity score approach to analyse the impact from SSRIs on risk for suicide attempts. Every suicide attempt and redeemed prescription of SSRIs was analysed by Cox regression. We found a significant overlap between redeeming a prescription on SSRIs and subsequent suicide attempt. The risk for suicide attempt was highest in the first 3 months after redeeming the first prescription. The hazard ratio for suicide attempts after redeeming a prescription was estimated to 5.23, 95% CI 4.82-5.68. We conclude that the risk of suicide attempt is higher for young people in the first months after redeeming their first prescription for SSRIs, compared to non-users. For SSRI users with lower propensity score (fewer risk factors for SSRIs) the risk of suicide attempt is estimated to be highest. Although the design may miss some explicit reason for prescription of SSRIs and SSRIs might be a marker for those in high risk rather than a causal risk factor, we would recommend systematic risk assessment in the period after redeeming the first prescription.

Cohort profile: the Spanish WORKing life Social Security (WORKss) cohort study.

PubMed

López Gómez, María Andrée; Durán, Xavier; Zaballa, Elena; Sanchez-Niubo, Albert; Delclos, George L; Benavides, Fernando G

2016-03-07

The global economy is changing the labour market and social protection systems in Europe. The effect of both changes on health needs to be monitored in view of an ageing population and the resulting increase in prevalence of chronic health conditions. The Spanish WORKing life Social Security (WORKss) cohort study provides unique longitudinal data to study the impact of labour trajectories and employment conditions on health, in terms of sickness absence, permanent disability and death. The WORKss cohort originated from the Continuous Working Life Sample (CWLS) generated by the General Directorate for the Organization of the Social Security in Spain. The CWLS contains a 4% representative sample of all individuals in contact with the Social Security system. The WORKss cohort exclusively includes individuals with a labour trajectory from 1981 or later. In 2004, the cohort was initiated with 1,022 ,79 Social Security members: 840,770 (82.2%) contributors and 182,009 (17.8%) beneficiaries aged 16 and older. The WORKss cohort includes demographic characteristics, chronological data about employment history, retirement, permanent disability and death. These data make possible the measurement of incidence of permanent disability, the number of potential years of working life lost, and the number of contracts and inactive periods with the Social Security system. The WORKss cohort was linked to temporary sickness absence registries to study medical diagnoses that lead to permanent disability and consequently to an earlier exit from the labour market in unhealthy conditions. Thanks to its administrative source, the WORKss cohort study will continue follow-up in the coming years, keeping the representativeness of the Spanish population affiliated to the Social Security system. The linkage between the WORKss cohort and temporary sickness absence registries is envisioned to continue. Future plans include the linkage of the cohort with mortality registries. Published by the BMJ

Embedding clinical interventions into observational studies

PubMed Central

Newman, Anne B.; Avilés-Santa, M. Larissa; Anderson, Garnet; Heiss, Gerardo; Howard, Wm. James; Krucoff, Mitchell; Kuller, Lewis H.; Lewis, Cora E.; Robinson, Jennifer G.; Taylor, Herman; Treviño, Roberto P.; Weintraub, William

2017-01-01

Novel approaches to observational studies and clinical trials could improve the cost-effectiveness and speed of translation of research. Hybrid designs that combine elements of clinical trials with observational registries or cohort studies should be considered as part of a long-term strategy to transform clinical trials and epidemiology, adapting to the opportunities of big data and the challenges of constrained budgets. Important considerations include study aims, timing, breadth and depth of the existing infrastructure that can be leveraged, participant burden, likely participation rate and available sample size in the cohort, required sample size for the trial, and investigator expertise. Community engagement and stakeholder (including study participants) support are essential for these efforts to succeed. PMID:26611435

Predictive Accuracy of the Veterans Aging Cohort Study (VACS) Index for Mortality with HIV Infection: A North American Cross Cohort Analysis

PubMed Central

Justice, AC; Modur, S; Tate, JP; Althoff, KN; Jacobson, LP; Gebo, K; Kitahata, M; Horberg, M; Brooks, J; Buchacz, K; Rourke, SB; Rachlis, A; Napravnik, S; Eron, J; Willig, H; Moore, R; Kirk, GD; Bosch, R; Rodriguez, B; Hogg, RS; Thorne, J; Goedert, JJ; Klein, M; Gill, MJ; Deeks, S; Sterling, TR; Anastos, K; Gange, SJ

2013-01-01

Background By supplementing an index composed of HIV biomarkers and age (Restricted Index) with measures of organ injury, the Veterans Aging Cohort Study (VACS) Index more completely reflects risk of mortality. We compare the accuracy of the VACS and Restricted Indices 1) among subjects outside the Veterans Healthcare System (VA), 2) over 1–5 years of prior exposure to antiretroviral therapy (ART), and 3) within important patient subgroups. Methods We used data from 13 cohorts in the North American AIDS Cohort Collaboration (NA-ACCORD, n=10, 835) limiting analyses to HIV-infected subjects with at least 12 months exposure to ART. Variables included demographic, laboratory (CD4 count, HIV-1 RNA, hemoglobin, platelets, aspartate and alanine transaminase, creatinine and hepatitis C status), and survival. We used C statistic and net reclassification improvement (NRI) to test discrimination varying prior ART exposure from 1–5 years. We then combined VA (n=5,066) and NA-ACCORD data, fit a parametric survival model, and compared predicted to observed mortality by cohort, gender, age, race, and HIV-1 RNA level. Results Mean follow-up was 3.3 years (655 deaths). Compared with the Restricted Index, the VACS Index showed greater discrimination (C statistic: 0.77 vs. 0.74; NRI 12%; p<0.0001). NRI was highest among those with HIV-1 RNA<500 copies/ml (25%) and age ≥50 years (20%). Predictions were similar to observed mortality among all subgroups. Conclusion VACS Index scores discriminate risk and translate into accurate mortality estimates over 1–5 years of exposures to ART and for diverse patient subgroups from North American PMID:23187941

A review of published analyses of case-cohort studies and recommendations for future reporting.

PubMed

Sharp, Stephen J; Poulaliou, Manon; Thompson, Simon G; White, Ian R; Wood, Angela M

2014-01-01

The case-cohort study design combines the advantages of a cohort study with the efficiency of a nested case-control study. However, unlike more standard observational study designs, there are currently no guidelines for reporting results from case-cohort studies. Our aim was to review recent practice in reporting these studies, and develop recommendations for the future. By searching papers published in 24 major medical and epidemiological journals between January 2010 and March 2013 using PubMed, Scopus and Web of Knowledge, we identified 32 papers reporting case-cohort studies. The median subcohort sampling fraction was 4.1% (interquartile range 3.7% to 9.1%). The papers varied in their approaches to describing the numbers of individuals in the original cohort and the subcohort, presenting descriptive data, and in the level of detail provided about the statistical methods used, so it was not always possible to be sure that appropriate analyses had been conducted. Based on the findings of our review, we make recommendations about reporting of the study design, subcohort definition, numbers of participants, descriptive information and statistical methods, which could be used alongside existing STROBE guidelines for reporting observational studies.

Cohort profile: the Geoscience and Health Cohort Consortium (GECCO) in the Netherlands

PubMed Central

Timmermans, Erik J; Lakerveld, Jeroen; Beulens, Joline W J; Boomsma, Dorret I; Kramer, Sophia E; Oosterman, Mirjam; Willemsen, Gonneke; Stam, Mariska; Nijpels, Giel; Schuengel, Carlo; Smit, Jan H; Brunekreef, Bert; Dekkers, Jasper E C; Deeg, Dorly J H; Penninx, Brenda W J H; Huisman, Martijn

2018-01-01

Purpose In the Netherlands, a great variety of objectively measured geo-data is available, but these data are scattered and measured at varying spatial and temporal scales. The centralisation of these geo-data and the linkage of these data to individual-level data from longitudinal cohort studies enable large-scale epidemiological research on the impact of the environment on public health in the Netherlands. In the Geoscience and Health Cohort Consortium (GECCO), six large-scale and ongoing cohort studies have been enriched with a variety of existing geo-data. Here, we introduce GECCO by describing: (1) the phenotypes of the involved cohort studies, (2) the collected geo-data and their sources, (3) the methodology that was used to link the collected geo-data to individual cohort studies, (4) the similarity of commonly used geo-data between our consortium and the nationwide situation in the Netherlands and (5) the distribution of geo-data within our consortium. Participants GECCO includes participants from six prospective cohort studies (eg, 44 657 respondents (18–100 years) in 2006) and it covers all municipalities in the Netherlands. Using postal code information of the participants, geo-data on the address-level, postal code-level as well as neighbourhood-level could be linked to individual-level cohort data. Findings to date The geo-data could be successfully linked to almost all respondents of all cohort studies, with successful data-linkage rates ranging from 97.1% to 100.0% between cohort studies. The results show variability in geo-data within and across cohorts. GECCO increases power of analyses, provides opportunities for cross-checking and replication, ensures sufficient geographical variation in environmental determinants and allows for nuanced analyses on specific subgroups. Future plans GECCO offers unique opportunities for (longitudinal) studies on the complex relationships between the environment and health outcomes. For example, GECCO will be

Cohort profile: the Geoscience and Health Cohort Consortium (GECCO) in the Netherlands.

PubMed

Timmermans, Erik J; Lakerveld, Jeroen; Beulens, Joline W J; Boomsma, Dorret I; Kramer, Sophia E; Oosterman, Mirjam; Willemsen, Gonneke; Stam, Mariska; Nijpels, Giel; Schuengel, Carlo; Smit, Jan H; Brunekreef, Bert; Dekkers, Jasper E C; Deeg, Dorly J H; Penninx, Brenda W J H; Huisman, Martijn

2018-06-09

In the Netherlands, a great variety of objectively measured geo-data is available, but these data are scattered and measured at varying spatial and temporal scales. The centralisation of these geo-data and the linkage of these data to individual-level data from longitudinal cohort studies enable large-scale epidemiological research on the impact of the environment on public health in the Netherlands. In the Geoscience and Health Cohort Consortium (GECCO), six large-scale and ongoing cohort studies have been enriched with a variety of existing geo-data. Here, we introduce GECCO by describing: (1) the phenotypes of the involved cohort studies, (2) the collected geo-data and their sources, (3) the methodology that was used to link the collected geo-data to individual cohort studies, (4) the similarity of commonly used geo-data between our consortium and the nationwide situation in the Netherlands and (5) the distribution of geo-data within our consortium. GECCO includes participants from six prospective cohort studies (eg, 44 657 respondents (18-100 years) in 2006) and it covers all municipalities in the Netherlands. Using postal code information of the participants, geo-data on the address-level, postal code-level as well as neighbourhood-level could be linked to individual-level cohort data. The geo-data could be successfully linked to almost all respondents of all cohort studies, with successful data-linkage rates ranging from 97.1% to 100.0% between cohort studies. The results show variability in geo-data within and across cohorts. GECCO increases power of analyses, provides opportunities for cross-checking and replication, ensures sufficient geographical variation in environmental determinants and allows for nuanced analyses on specific subgroups. GECCO offers unique opportunities for (longitudinal) studies on the complex relationships between the environment and health outcomes. For example, GECCO will be used for further research on environmental determinants

Social inequalities in quality of life in a cohort of women diagnosed with breast cancer in Barcelona (DAMA Cohort).

PubMed

Graells-Sans, Ariadna; Serral, Gemma; Puigpinós-Riera, Rosa

2018-06-01

Breast cancer is a challenge for women's health-related quality of life (QoL), compromising their physical health and emotional well-being. QoL is equally distributed among different social groups. The aim of this study to analyze the impact of clinical characteristics and social determinants of health on the QoL of a cohort of women diagnosed and/or treated for breast cancer between 2003 and 2013 in one of the main hospitals in Barcelona's public health network. We performed a descriptive cross-sectional study in a cohort of 2235 women with various stages of breast cancer at different stages of their disease. Data were obtained using questionnaires QLQ-C30 and QLQ-BR23 from the European Organization for Research and Treatment of Cancer (EORTC), which include a set of functional and symptomatic scales. We conducted descriptive and bivariate analysis using the Chi-Square test and adjusted for relevant variables using logistic regression. The dependent variables were the functional scales of QoL and the independent variables were sociodemographic and clinical variables. We observed significant differences for most QoL functions. Women from the most disadvantaged class, those in social isolation, or those who had suffered relapses showed the poorest results for most of the function scales. In contrast, age had differential effects depending on the function studied. The QoL of women diagnosed with breast cancer is closely linked to both their social and economic status, and to their stage of disease progression. It is necessary to explore interventions that focus on the social determinants of health in order to mitigate their effects on breast cancer survivors' QoL. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

An observational cohort study on persistency of internal teat sealant residues in milk after calving in dairy cows.

PubMed

Kabera, Fidèle; Dufour, Simon; Keefe, Greg; Roy, Jean-Philippe

2018-04-04

Our objectives were to evaluate the prevalence of quarters with an observable internal teat sealant (ITS) plug at first milking following calving and investigate persistency of ITS residues in milk after calving. An observational cohort study was carried out on 557 quarters of 156 cows treated with ITS in 6 farms in Quebec, Canada. The presence of an ITS plug at first milking and ITS residues in milk at each milking were observed by producers. The effects of various factors on the odds of observing an ITS plug and persistency of ITS residues in milk were studied using generalized logistic mixed and generalized negative binomial mixed models, respectively. Milk samples were taken on the day before dry-off and on 2 occasions after calving for bacterial identification to detect intramammary infection (IMI) using bacteriological culture followed by MALDI-TOF identification. The association between the absence of an ITS plug and the presence of new IMI was assessed using a mixed logistic regression model. Internal teat sealant plugs after calving were more often observed in rear quarters and in quarters receiving ITS alone at drying-off versus antimicrobial and ITS. We observed an average (standard deviation) persistency of 4.0 d (2.3 d). When an ITS plug was still present at first milking (83% of quarters), the elimination of ITS residues in milk after calving was significantly longer (4.5 d, on average) compared with 1.2 d when an ITS plug was absent. In cows with an ITS plug at calving, we observed a higher number of days of excretion in older cows. When a plug could not be observed, rear quarters, older cows, and cows with a long dry period duration excreted ITS residues for a significantly longer period. The lack of a significant association between the absence of a plug and the odds of new IMI at calving suggests that despite the loss of the plug, cows were still protected against new IMI. Although we were able to highlight some statistically significant risk

The History and Progression of Manual Rounds: A Structured Peer Observation Process for Teachers in Urban School Settings

ERIC Educational Resources Information Center

Hunzicker, Jana; Tripses, Jenny; Wolffe, Robert; Jenkins, Taunya; Ewan-Skorczewski, Martha; Chrosniak, Patricia

2017-01-01

Research shows that half of all teachers working in urban school settings leave the profession within five years, and many who choose to leave are the ones who are most effective (Coggins & Diffenbaugh, 2013.) Manual Rounds, a structured peer observation process based on the established practice of instructional rounds, was implemented at…

COHORT EFFECTS OF SUICIDE MORTALITY ARE SEX SPECIFIC IN THE RAPIDLY DEVELOPED HONG KONG CHINESE POPULATION, 1976-2010.

PubMed

Chung, Roger Y; Yip, Benjamin H K; Chan, Sandra S M; Wong, Samuel Y S

2016-06-01

To examine temporal variations of age, period, and cohort on suicide mortality rate in Hong Kong (HK) from 1976 to 2010, and speculate the macroenvironmental mechanisms of the observed trends. Poisson age-period-cohort modeling was used to delineate the effects of age, period, and cohort on suicide mortality. Analysis by sex was also conducted to examine if gender difference exists for suicidal behaviours. Age-cohort model provides the best fit to the mortality data, implying that the cohort effect is likely to explain more of the contributions to HK's suicide mortality pattern than the period effect. Risk of suicide mortality increases nonlinearly with age and accelerates after age 65-69 for both sexes. Moreover, the cohort effects differ between the sexes-risk of mortality increases continually for men born after 1961, but no change is observed for women since the 1941 cohort. With increased risk of suicide mortality in younger cohorts and the age effect of suicide mortality, we may see future increase in suicide mortality as these younger cohorts age. Further studies are needed to clarify plausible associations between broader sociohistorical changes in the population impacting psychological risk factors and suicidal behaviour to better inform suicide prevention strategies. © 2015 Wiley Periodicals, Inc.

Sardasht-Iran cohort study of chemical warfare victims: design and methods.

PubMed

Ghazanfari, Tooba; Faghihzadeh, Soghrat; Aragizadeh, Hassan; Soroush, Mohammad-Reza; Yaraee, Roya; Mohammad Hassan, Zuhair; Foroutan, Abbas; Vaez-Mahdavi, Mohammad-Reza; Javadi, Mohammad-Ali; Moaiedmohseni, Sakine; Azizi, Fereidoun; Panahi, Yunes; Mostafaie, Ali; Ghasemi, Hassan; Shams, Jalaleddin; Pourfarzam, Shahryar; Jalali-Nadoushan, Mohammad-Reza; Fallahi, Faramarz; Ebtekar, Massoumeh; Davoudi, Seyyed-Masoud; Ghazanfari, Zeinab; Ardestani, Sussan K; Shariat-Panahi, Shamsa; Moin, Athar; Rezaei, Abbas; Kariminia, Amina; Ajdary, Soheila; Mahmoudi, Mahmoud; Roshan, Rasoul; Ghaderi, Sulayman; Babai, Mahmoud; Naghizadeh, Mohammad-Mehdi; Ghanei, Mohammad-Mostafa

2009-01-01

Insights into long-term clinical consequences of sulfur mustard have emerged from some investigations but less is known about the basic and molecular mechanisms of these complications. Sardasht-Iran Cohort Study is a comprehensive historical cohort study on Sardasht chemical victims' population which was designed to find out the long-term complications of sulfur mustard exposure and the basic mechanisms underlying clinical manifestations. This paper describes the design and methodology of Sardasht-Iran Cohort Study. In Sardasht-Iran Cohort Study, 500 individuals including 372 subjects from Sardasht, as the exposed group, and 128 subjects from Rabat, as the unexposed age-matched control group were evaluated. The exposed group was divided into two groups based on the severity of clinical complications at the time of exposure. Different samples including blood, sputum, saliva, tear, urine, and semen were collected for immunologic, hematologic, biochemical, and other laboratory analysis. Data were gathered from medical records, clinical examinations, laboratory tests, and questionnaires for psychological and lifestyle situations. The important distinctions setting this study apart from the previous ones are discussed. The Sardasht-Iran Cohort Study provides important information on various aspects of long-term consequences of sulfur mustard exposure. This database will provide a better position to suggest guidelines for the diagnosis, treatment, and prevention of delayed complications in the patients exposed to sulfur mustard.

Maternal Malaria and Malnutrition (M3) initiative, a pooled birth cohort of 13 pregnancy studies in Africa and the Western Pacific.

PubMed

Unger, Holger W; Cates, Jordan E; Gutman, Julie; Briand, Valerie; Fievet, Nadine; Valea, Innocent; Tinto, Halidou; d'Alessandro, Umberto; Landis, Sarah H; Adu-Afarwuah, Seth; Dewey, Kathryn G; Ter Kuile, Feiko; Dellicour, Stephanie; Ouma, Peter; Slutsker, Laurence; Terlouw, Dianne J; Kariuki, Simon; Ayisi, John; Nahlen, Bernard; Desai, Meghna; Madanitsa, Mwayi; Kalilani-Phiri, Linda; Ashorn, Per; Maleta, Kenneth; Mueller, Ivo; Stanisic, Danielle; Schmiegelow, Christentze; Lusingu, John; Westreich, Daniel; van Eijk, Anna Maria; Meshnick, Steven; Rogerson, Stephen

2016-12-21

The Maternal Malaria and Malnutrition (M3) initiative has pooled together 13 studies with the hope of improving understanding of malaria-nutrition interactions during pregnancy and to foster collaboration between nutritionists and malariologists. Data were pooled on 14 635 singleton, live birth pregnancies from women who had participated in 1 of 13 pregnancy studies. The 13 studies cover 8 countries in Africa and Papua New Guinea in the Western Pacific conducted from 1996 to 2015. Data are available at the time of antenatal enrolment of women into their respective parent study and at delivery. The data set comprises essential data such as malaria infection status, anthropometric assessments of maternal nutritional status, presence of anaemia and birth weight, as well as additional variables such gestational age at delivery for a subset of women. Participating studies are described in detail with regard to setting and primary outcome measures, and summarised data are available from each contributing cohort. This pooled birth cohort is the largest pregnancy data set to date to permit a more definite evaluation of the impact of plausible interactions between poor nutritional status and malaria infection in pregnant women on fetal growth and gestational length. Given the current comparative lack of large pregnancy cohorts in malaria-endemic settings, compilation of suitable pregnancy cohorts is likely to provide adequate statistical power to assess malaria-nutrition interactions, and could point towards settings where such interactions are most relevant. The M3 cohort may thus help to identify pregnant women at high risk of adverse outcomes who may benefit from tailored intensive antenatal care including nutritional supplements and alternative or intensified malaria prevention regimens, and the settings in which these interventions would be most effective. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence

A prospective, observational cohort study of the seasonal dynamics of airway pathogens in the aetiology of exacerbations in COPD

PubMed Central

Wilkinson, Tom M A; Aris, Emmanuel; Bourne, Simon; Clarke, Stuart C; Peeters, Mathieu; Pascal, Thierry G; Schoonbroodt, Sonia; Tuck, Andrew C; Kim, Viktoriya; Williams, Nicholas; Williams, Anthony; Wootton, Stephen; Devaster, Jeanne-Marie

2017-01-01

Background The aetiology of acute exacerbations of COPD (AECOPD) is incompletely understood. Understanding the relationship between chronic bacterial airway infection and viral exposure may explain the incidence and seasonality of these events. Methods In this prospective, observational cohort study (NCT01360398), patients with COPD aged 40–85 years underwent sputum sampling monthly and at exacerbation for detection of bacteria and viruses. Results are presented for subjects in the full cohort, followed for 1 year. Interactions between exacerbation occurrence and pathogens were investigated by generalised estimating equation and stratified conditional logistic regression analyses. Findings The mean exacerbation rate per patient-year was 3.04 (95% CI 2.63 to 3.50). At AECOPD, the most common bacterial species were non-typeable Haemophilus influenzae (NTHi) and Moraxella catarrhalis, and the most common virus was rhinovirus. Logistic regression analyses (culture bacterial detection) showed significant OR for AECOPD occurrence when M. catarrhalis was detected regardless of season (5.09 (95% CI 2.76 to 9.41)). When NTHi was detected, the increased risk of exacerbation was greater in high season (October–March, OR 3.04 (1.80 to 5.13)) than low season (OR 1.22 (0.68 to 2.22)). Bacterial and viral coinfection was more frequent at exacerbation (24.9%) than stable state (8.6%). A significant interaction was detected between NTHi and rhinovirus presence and AECOPD risk (OR 5.18 (1.92 to 13.99); p=0.031). Conclusions AECOPD aetiology varies with season. Rises in incidence in winter may be driven by increased pathogen presence as well as an interaction between NTHi airway infection and effects of viral infection. Trial registration number Results, NCT01360398. PMID:28432209

Timing of solid food introduction and obesity: Hong Kong's "children of 1997" birth cohort.

PubMed

Lin, Shi Lin; Leung, Gabriel M; Lam, Tai Hing; Schooling, C Mary

2013-05-01

Some observational studies in Western settings show that early introduction of solid food is associated with subsequent obesity. However, introduction of solid food and obesity share social patterning. We examined the association of the timing of the introduction of solid food with BMI and overweight (including obesity) into adolescence in a developed non-Western setting, in which childhood obesity is less clearly socially patterned. We used generalized estimating equation models to estimate the adjusted associations of the timing of the introduction of solid food (<3, 3-4, 5-6, 7-8, and >8 months) with BMI z score and overweight (including obesity) at different growth phases (infancy, childhood, and puberty) in 7809 children (88% follow-up) from a Chinese birth cohort, "Children of 1997." We assessed if the associations varied with gender or breastfeeding. We used multiple imputation for missing exposure and confounders. The introduction of solid food at <3 months of age was associated with lower family socioeconomic position (SEP) but was not clearly associated with BMI or overweight (including obesity) in infancy [mean difference in BMI z score: 0.01; 95% confidence interval (CI): -0.14 to 0.17], childhood (0.14; 95% CI: -0.11 to 0.40), or at puberty (0.22; 95% CI: -0.07 to 0.52), adjusted for SEP and infant and maternal characteristics. In a non-Western developed setting, there was no clear association of the early introduction of solid food with childhood obesity. Together with the inconsistent evidence from studies in Western settings, this finding suggests that any observed associations might simply be residual confounding by SEP.

Breast Cancer Incidence in a Cohort of U.S. Flight Attendants

PubMed Central

Schubauer-Berigan, Mary K.; Anderson, Jeri L.; Hein, Misty J.; Little, Mark P.; Sigurdson, Alice J.; Pinkerton, Lynne E.

2015-01-01

Background Flight attendants may have elevated breast cancer incidence (BCI). We evaluated BCI’s association with cosmic radiation dose and circadian rhythm disruption among 6,093 female former U.S. flight attendants. Methods We collected questionnaire data on BCI and risk factors for breast cancer from 2002–2005. We conducted analyses to evaluate (i) BCI in the cohort compared to the U.S. population; and (ii) exposure-response relations. We applied an indirect adjustment to estimate whether parity and age at first birth (AFB) differences between the cohort and U.S. population could explain BCI that differed from expectation. Results BCI was elevated but may be explained by lower parity and older AFB in the cohort than among U.S. women. BCI was not associated with exposure metrics in the cohort overall. Significant positive associations with both were observed only among women with parity of three or more. Conclusions Future cohort analyses may be informative on the role of these occupational exposures and non-occupational risk factors. PMID:25678455

The impact of breast cancer-specific birth cohort effects among younger and older Chinese populations.

PubMed

Sung, Hyuna; Rosenberg, Philip S; Chen, Wan-Qing; Hartman, Mikael; Lim, Wei-Yen; Chia, Kee Seng; Wai-Kong Mang, Oscar; Tse, Lapah; Anderson, William F; Yang, Xiaohong R

2016-08-01

Historically low breast cancer incidence rates among Asian women have risen worldwide; purportedly due to the adoption of a "Western" life style among younger generations (i.e., the more recent birth cohorts). However, no study has simultaneously compared birth cohort effects between both younger and older women in different Asian and Western populations. Using cancer registry data from rural and urban China, Singapore and the United States (1990-2008), we estimated age-standardized incidence rates (ASR), annual percentage change (EAPC) in the ASR, net drifts, birth cohort specific incidence rates and cohort rate ratios (CRR). Younger (30-49 years, 1943-1977 birth cohorts) and older women (50-79 years; 1913-1957 birth cohorts) were assessed separately. CRRs among Chinese populations were estimated using birth cohort specific rates with US non-Hispanic white women (NHW) serving as the reference population with an assigned CRR of 1.0. We observed higher EAPCs and net drifts among those Chinese populations with lower ASRs. Similarly, we observed the most rapidly increasing cohort-specific incidence rates among those Chinese populations with the lowest baseline CRRs. Both trends were more significant among older than younger women. Average CRRs were 0.06-0.44 among older and 0.18-0.81 among younger women. Rapidly rising cohort specific rates have narrowed the historic disparity between Chinese and US NHW breast cancer populations particularly in regions with the lowest baseline rates and among older women. Future analytic studies are needed to investigate risk factors accounting for the rapid increase of breast cancer among older and younger women separately in Asian populations. © 2016 UICC.

Identification and Construction of Combinatory Cancer Hallmark-Based Gene Signature Sets to Predict Recurrence and Chemotherapy Benefit in Stage II Colorectal Cancer.

PubMed

Gao, Shanwu; Tibiche, Chabane; Zou, Jinfeng; Zaman, Naif; Trifiro, Mark; O'Connor-McCourt, Maureen; Wang, Edwin

2016-01-01

Decisions regarding adjuvant therapy in patients with stage II colorectal cancer (CRC) have been among the most challenging and controversial in oncology over the past 20 years. To develop robust combinatory cancer hallmark-based gene signature sets (CSS sets) that more accurately predict prognosis and identify a subset of patients with stage II CRC who could gain survival benefits from adjuvant chemotherapy. Thirteen retrospective studies of patients with stage II CRC who had clinical follow-up and adjuvant chemotherapy were analyzed. Respective totals of 162 and 843 patients from 2 and 11 independent cohorts were used as the discovery and validation cohorts, respectively. A total of 1005 patients with stage II CRC were included in the 13 cohorts. Among them, 84 of 416 patients in 3 independent cohorts received fluorouracil-based adjuvant chemotherapy. Identification of CSS sets to predict relapse-free survival and identify a subset of patients with stage II CRC who could gain substantial survival benefits from fluorouracil-based adjuvant chemotherapy. Eight cancer hallmark-based gene signatures (30 genes each) were identified and used to construct CSS sets for determining prognosis. The CSS sets were validated in 11 independent cohorts of 767 patients with stage II CRC who did not receive adjuvant chemotherapy. The CSS sets accurately stratified patients into low-, intermediate-, and high-risk groups. Five-year relapse-free survival rates were 94%, 78%, and 45%, respectively, representing 60%, 28%, and 12% of patients with stage II disease. The 416 patients with CSS set-defined high-risk stage II CRC who received fluorouracil-based adjuvant chemotherapy showed a substantial gain in survival benefits from the treatment (ie, recurrence reduced by 30%-40% in 5 years). The CSS sets substantially outperformed other prognostic predictors of stage 2 CRC. They are more accurate and robust for prognostic predictions and facilitate the identification of patients with stage

Outcomes in Adults With Acute Liver Failure Between 1998 and 2013: An Observational Cohort Study.

PubMed

Reuben, Adrian; Tillman, Holly; Fontana, Robert J; Davern, Timothy; McGuire, Brendan; Stravitz, R Todd; Durkalski, Valerie; Larson, Anne M; Liou, Iris; Fix, Oren; Schilsky, Michael; McCashland, Timothy; Hay, J Eileen; Murray, Natalie; Shaikh, Obaid S; Ganger, Daniel; Zaman, Atif; Han, Steven B; Chung, Raymond T; Smith, Alastair; Brown, Robert; Crippin, Jeffrey; Harrison, M Edwyn; Koch, David; Munoz, Santiago; Reddy, K Rajender; Rossaro, Lorenzo; Satyanarayana, Raj; Hassanein, Tarek; Hanje, A James; Olson, Jody; Subramanian, Ram; Karvellas, Constantine; Hameed, Bilal; Sherker, Averell H; Robuck, Patricia; Lee, William M

2016-06-07

Acute liver failure (ALF) is a rare syndrome of severe, rapid-onset hepatic dysfunction-without prior advanced liver disease-that is associated with high morbidity and mortality. Intensive care and liver transplantation provide support and rescue, respectively. To determine whether changes in causes, disease severity, treatment, or 21-day outcomes have occurred in recent years among adult patients with ALF referred to U.S. tertiary care centers. Prospective observational cohort study. (ClinicalTrials .gov: NCT00518440). 31 liver disease and transplant centers in the United States. Consecutively enrolled patients-without prior advanced liver disease-with ALF (n = 2070). Clinical features, treatment, and 21-day outcomes were compared over time annually for trends and were also stratified into two 8-year periods (1998 to 2005 and 2006 to 2013). Overall clinical characteristics, disease severity, and distribution of causes remained similar throughout the study period. The 21-day survival rates increased between the two 8-year periods (overall, 67.1% vs. 75.3%; transplant-free survival [TFS], 45.1% vs. 56.2%; posttransplantation survival, 88.3% vs. 96.3% [P < 0.010 for each]). Reductions in red blood cell infusions (44.3% vs. 27.6%), plasma infusions (65.2% vs. 47.1%), mechanical ventilation (65.7% vs. 56.1%), and vasopressors (34.9% vs. 27.8%) were observed, as well as increased use of N-acetylcysteine (48.9% vs. 69.3% overall; 15.8% vs. 49.4% [P < 0.001] in patients with ALF not due to acetaminophen toxicity). When examined longitudinally, overall survival and TFS increased throughout the 16-year period. The duration of enrollment, the number of patients enrolled, and possibly the approaches to care varied among participating sites. The results may not be generalizable beyond such specialized centers. Although characteristics and severity of ALF changed little over 16 years, overall survival and TFS improved significantly. The effects of specific changes in

Genome-Wide Gene Expression in relation to Age in Large Laboratory Cohorts of Drosophila melanogaster

PubMed Central

Carlson, Kimberly A.; Gardner, Kylee; Pashaj, Anjeza; Carlson, Darby J.; Yu, Fang; Eudy, James D.; Zhang, Chi; Harshman, Lawrence G.

2015-01-01

Aging is a complex process characterized by a steady decline in an organism's ability to perform life-sustaining tasks. In the present study, two cages of approximately 12,000 mated Drosophila melanogaster females were used as a source of RNA from individuals sampled frequently as a function of age. A linear model for microarray data method was used for the microarray analysis to adjust for the box effect; it identified 1,581 candidate aging genes. Cluster analyses using a self-organizing map algorithm on the 1,581 significant genes identified gene expression patterns across different ages. Genes involved in immune system function and regulation, chorion assembly and function, and metabolism were all significantly differentially expressed as a function of age. The temporal pattern of data indicated that gene expression related to aging is affected relatively early in life span. In addition, the temporal variance in gene expression in immune function genes was compared to a random set of genes. There was an increase in the variance of gene expression within each cohort, which was not observed in the set of random genes. This observation is compatible with the hypothesis that D. melanogaster immune function genes lose control of gene expression as flies age. PMID:26090231

Characteristics and outcomes of older HIV-infected patients receiving antiretroviral therapy in Malawi: A retrospective observation cohort study.

PubMed

Tweya, Hannock; Feldacker, Caryl; Heller, Tom; Gugsa, Salem; Ng'ambi, Wingston; Nthala, Omisher; Kalulu, Mike; Chiwoko, Jane; Banda, Rabecca; Makwinja, Agness; Phiri, Sam

2017-01-01

To estimate patients enrolling on antiretroviral therapy (ART) over time; describe trends in baseline characteristics; and compare immunological response, loss to follow-up (LTFU), and mortality by three age groups (25-39, 40-49 and ≥50 years). A retrospective observation cohort study. This study used routine ART data from two public clinics in Lilongwe, Malawi. All HIV-infected individuals, except pregnant or breastfeeding women, aged ≥ 25 years at ART initiation between 2006 and 2015 were included. Poisson regression models estimated risk of mortality, stratified by age groups. Of 37,378 ART patients, 3,406 were ≥ 50 years old. Patients aged ≥ 50 years initiated ART with more advanced WHO clinical stage and lower CD4 cell count than their younger counterparts. Older patients had a significantly slower immunological response to ART in the first 18 months on ART compared to patients aged 25-39 years (p = 0.04). Overall mortality rates were 2.3 (95% confidence Interval (CI) 2.2-2.4), 2.9 (95% CI 2.7-3.2) and 4.6 (95% CI 4.2-5.1) per 100 person-years in patients aged 25-39 years, 40-49 years and 50 years and older, respectively. Overall LTFU rates were 6.3 (95% CI 6.1-6.5), 4.5 (95% CI 4.2-4.7), and 5.6 (95% CI 5.1-6.1) per 100 person years among increasing age cohorts. The proportion of patients aged ≥ 50 years and newly enrolling into ART care remained stable at 9% while the proportion of active ART patients aged ≥50 years increased from 10% in 2006 to 15% in 2015. Older people had slower immunological response and higher mortality. Malawi appears to be undergoing a demographic shift in people living with HIV. Increased consideration of long-term ART-related problems, drug-drug interactions and age-related non-communicable diseases is warranted.

Characteristics and outcomes of older HIV-infected patients receiving antiretroviral therapy in Malawi: A retrospective observation cohort study

PubMed Central

Tweya, Hannock; Feldacker, Caryl; Heller, Tom; Gugsa, Salem; Ng’ambi, Wingston; Nthala, Omisher; Kalulu, Mike; Chiwoko, Jane; Banda, Rabecca; Makwinja, Agness; Phiri, Sam

2017-01-01

Objective To estimate patients enrolling on antiretroviral therapy (ART) over time; describe trends in baseline characteristics; and compare immunological response, loss to follow-up (LTFU), and mortality by three age groups (25–39, 40–49 and ≥50 years). Design A retrospective observation cohort study. Methods This study used routine ART data from two public clinics in Lilongwe, Malawi. All HIV-infected individuals, except pregnant or breastfeeding women, aged ≥ 25 years at ART initiation between 2006 and 2015 were included. Poisson regression models estimated risk of mortality, stratified by age groups. Results Of 37,378 ART patients, 3,406 were ≥ 50 years old. Patients aged ≥ 50 years initiated ART with more advanced WHO clinical stage and lower CD4 cell count than their younger counterparts. Older patients had a significantly slower immunological response to ART in the first 18 months on ART compared to patients aged 25–39 years (p = 0.04). Overall mortality rates were 2.3 (95% confidence Interval (CI) 2.2–2.4), 2.9 (95% CI 2.7–3.2) and 4.6 (95% CI 4.2–5.1) per 100 person-years in patients aged 25–39 years, 40–49 years and 50 years and older, respectively. Overall LTFU rates were 6.3 (95% CI 6.1–6.5), 4.5 (95% CI 4.2–4.7), and 5.6 (95% CI 5.1–6.1) per 100 person years among increasing age cohorts. The proportion of patients aged ≥ 50 years and newly enrolling into ART care remained stable at 9% while the proportion of active ART patients aged ≥50 years increased from 10% in 2006 to 15% in 2015. Conclusion Older people had slower immunological response and higher mortality. Malawi appears to be undergoing a demographic shift in people living with HIV. Increased consideration of long-term ART-related problems, drug-drug interactions and age-related non-communicable diseases is warranted. PMID:28686636

The protocol of a population-based prospective cohort study in southwest of Iran to analyze common non-communicable diseases: Shahrekord cohort study.

PubMed

Khaledifar, Arsalan; Hashemzadeh, Morteza; Solati, Kamal; Poustchi, Hosseion; Bollati, Valentina; Ahmadi, Ali; Kheiri, Soleiman; Samani, Keihan Ghatreh; Banitalebi, Mehdi; Sedehi, Morteza; Malekzadeh, Reza

2018-05-25

Prospective cohort studies are considered ideal choices to study multiple outcomes and risk factors for Non-communicable diseases (NCDs). Our aim is to set-up the protocol and analyze risk factors, incidence rates, prevalence, trends, and the models of environmental and genetic determinants of NCDs and their outcomes as well as interaction among such determinants. Shahrekord cohort study (SCS) that is a population-based prospective, study on a cohort consisting of people aged 35-70 years started in November 2015 in Iran. The sample size of the original cohort is at least 10,000 people. Annual follow-ups (200,000 person-year) of the cohort were designed to be conducted up to 2036. Exposures (a detailed demographic, socioeconomic, general health, quality of life, physical activity, anthropometric indexes, stress, health literacy, social capital, nutrition and eating habits, lifestyle, occupational history, living place, blindness, deafness, electrocardiography, lung capacities, blood pressure, sleep, smoking and alcohol, contact to animals, physical examinations and medical history, dental health, used drugs and supplements, glucose and lipid profiles) were measured by relevant standard methods and questionnaires. Incidence of common NCDs (cardiovascular diseases, cancer, gastrointestinal, respiratory, renal, hepatic, accidents, injury and neurological diseases), trend of risk factors, hospitalization, disability, and death were considered the outcomes of the cohort. The definition of disease was determined based on the International Classification of Diseases 10th version (ICD-10). Routine hematologic and biochemical tests were conducted and an all-inclusive biobank (blood, hair, nail, and urine specimens) of the cohort was stored for future studies. All steps of data collection and examinations are directly monitored by the quality control team. The SCS is a unique study conducted in southwest of Iran that is a notable work given the climate conditions and

High virological suppression regardless of the genotypic susceptibility score after switching to a dolutegravir-based regimen: week 48 results in an observational cohort.

PubMed

Charpentier, Charlotte; Peytavin, Gilles; Lê, Minh P; Joly, Véronique; Cabras, Ornella; Perrier, Marine; Le Gac, Sylvie; Phung, Bao; Yazdanpanah, Yazdan; Descamps, Diane; Landman, Roland

2018-06-01

To assess, in a clinical cohort, the efficacy of switching current ART in virologically suppressed patients to a dolutegravir-based regimen, regardless of the genotypic susceptibility score (GSS). This was an observational single-centre study assessing ART-treated patients with plasma viral load (pVL) <50 copies/mL who were switched to a dolutegravir-based regimen with 1 year of follow-up. PCR negative was defined as an undetected PCR signal. Trough plasma concentration (C24) was determined using UPLC-MS/MS. Two hundred and thirty-nine patients initiated a dolutegravir-based regimen: 12%, 29% and 59% had a total GSS of 1 or 1.5 (group 1), 2 or 2.5 (group 2) and 3 (group 3), respectively. At switch initiation, the median time since first ART and the median duration with pVL <50 copies/mL were 13 years (IQR = 6-19) and 3 years (IQR = 1-6), respectively. Median times since last genotype were 9, 10 and 5 years for groups 1, 2 and 3, respectively. Twenty patients (8.4%) discontinued the dolutegravir-based regimen due to adverse events. During the study, 96.4% (n = 661/686) of all pVL were <50 copies/mL. Four patients (1.7%) experienced virological failure (two pVL >50 copies/mL) without emergence of resistance; these patients' GSSs were 2, 2.5, 3 and 3. The median dolutegravir C24 was 1545 ng/mL (IQR = 1150-2097). Of the patients with pVL <20 copies/mL, 72% were PCR negative during the follow-up, with no difference between the three groups of patients. This observational cohort study showed a high level of virological suppression maintenance in the first year following the switch to a dolutegravir-based regimen, even in patients with GSS ≤2.

Educator engagement and interaction and children's physical activity in early childhood education and care settings: an observational study protocol.

PubMed

Tonge, Karen L; Jones, Rachel A; Hagenbuchner, Markus; Nguyen, Tuc V; Okely, Anthony D

2017-02-07

The benefits of regular physical activity for children are significant. Previous research has addressed the quantity and quality of children's physical activity while in early childhood education and care (ECEC) settings, yet little research has investigated the social and physical environmental influences on physical activity in these settings. The outcomes of this study will be to measure these social and physical environmental influences on children's physical activity using a combination of a real-time location system (RTLS) (a closed system that tracks the location of movement of participants via readers and tags), accelerometry and direct observation. This study is the first of its kind to combine RTLSs and accelerometer data in ECEC settings. It is a cross-sectional study involving ∼100 educators and 500 children from 11 ECEC settings in the Illawarra region of New South Wales, Australia. A RTLS and Actigraph GT3X+ accelerometers will be concurrently used to measure the level and location of the children's and educators' physical activity while in outside environments. Children and educators will wear accelerometers on their hip that record triaxial acceleration data at 100 Hz. Children and educators will also wear a tag watch on their wrist that transmits a signal to anchors of the RTLS and the triangulation of signals will identify their specific location. In addition to these, up to three random periods (10-25 min in length) will be used to collect observational data each day and assessed with the classroom assessment and scoring system to measure the quality of interactions. In conjunction with the real-time location system (RTLS) and accelerometers, these observations will measure the relationship between the quality of interactions and children's physical activity. The results of this study will be disseminated through peer-reviewed publications and presentations. Ethical approval was obtained through the University of Wollongong Human Research

Impact of Malnutrition on Physical, Cognitive Function and Mortality among Older Men Living in Veteran Homes by Minimum Data Set: A Prospective Cohort Study in Taiwan.

PubMed

Chen, L-Y; Liu, L-K; Hwang, A-C; Lin, M-H; Peng, L-N; Chen, L-K; Lan, C-F; Chang, P-L

2016-01-01

To evaluate the prevalence of malnutrition and its impact on mortality, functional decline and cognitive impairment among elder residents in long-term care settings. A prospective cohort study. Two veteran homes in Taiwan. A total of 1,248 male residents aged equal or more than 65 years. Charlson's comorbidity index (CCI), Minimum data set (MDS), resident assessment protocols (RAP), Activity of daily living-Hierarchy scale, Cognitive Performance Scale, MDS Social engagement scale. The mean age of participants is 83.1 ± 5.1 years, and the prevalence of malnutrition was 6.1%. Inadequate dietary content (57.9%) and unintentional weight loss (31.6%) account for the majority of malnutrition identified by MDS tool. Higher 18-month mortality rate (25% vs. 14.2%), higher baseline CCI (median 1 vs. 0), and higher baseline sum of RAP triggers (median 8.5 vs. 5) were noted among residents with malnutrition. Furthermore, malnutrition was shown predictive for functional decline (OR: 3.096, 95% CI: 1.715-5.587) and potential cognitive improvement (OR: 2.469, 95% CI: 1.188-5.128) among survivors after adjustment for age, body mass index and CCI. Malnutrition among elder men residing in veteran homes was associated with multimorbidities and higher care complexity, and was predictive for mortality and functional decline.

Embedding clinical interventions into observational studies.

PubMed

Newman, Anne B; Avilés-Santa, M Larissa; Anderson, Garnet; Heiss, Gerardo; Howard, Wm James; Krucoff, Mitchell; Kuller, Lewis H; Lewis, Cora E; Robinson, Jennifer G; Taylor, Herman; Treviño, Roberto P; Weintraub, William

2016-01-01

Novel approaches to observational studies and clinical trials could improve the cost-effectiveness and speed of translation of research. Hybrid designs that combine elements of clinical trials with observational registries or cohort studies should be considered as part of a long-term strategy to transform clinical trials and epidemiology, adapting to the opportunities of big data and the challenges of constrained budgets. Important considerations include study aims, timing, breadth and depth of the existing infrastructure that can be leveraged, participant burden, likely participation rate and available sample size in the cohort, required sample size for the trial, and investigator expertise. Community engagement and stakeholder (including study participants) support are essential for these efforts to succeed. Copyright © 2015. Published by Elsevier Inc.

Cohort Default Rate Guide.

ERIC Educational Resources Information Center

Department of Education, Washington, DC. Default Management Div.

This guide is designed to assist schools with their Federal Family Education Loan Program (FFEL) and the William D. Ford Federal Direct Loan (Direct Loan) Program cohort default rate. The guide is a reference tool in understanding cohort default rates and processes. This guide incorporates two former guides, the "Draft Cohort Default Rate…

Structure and correlates of cognitive aging in a narrow age cohort.

PubMed

Tucker-Drob, Elliot M; Briley, Daniel A; Starr, John M; Deary, Ian J

2014-06-01

Aging-related changes occur for multiple domains of cognitive functioning. An accumulating body of research indicates that, rather than representing statistically independent phenomena, aging-related cognitive changes are moderately to strongly correlated across domains. However, previous studies have typically been conducted in age-heterogeneous samples over longitudinal time lags of 6 or more years, and have failed to consider whether results are robust to a comprehensive set of controls. Capitalizing on 3-year longitudinal data from the Lothian Birth Cohort of 1936, we took a longitudinal narrow age cohort approach to examine cross-domain cognitive change interrelations from ages 70 to 73 years. We fit multivariate latent difference score models to factors representing visuospatial ability, processing speed, memory, and crystallized ability. Changes were moderately interrelated, with a general factor of change accounting for 47% of the variance in changes across domains. Change interrelations persisted at close to full strength after controlling for a comprehensive set of demographic, physical, and medical factors including educational attainment, childhood intelligence, physical function, APOE genotype, smoking status, diagnosis of hypertension, diagnosis of cardiovascular disease, and diagnosis of diabetes. Thus, the positive manifold of aging-related cognitive changes is highly robust in that it can be detected in a narrow age cohort followed over a relatively brief longitudinal period, and persists even after controlling for many potential confounders. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Cohort profile: cerebral palsy in the Norwegian and Danish birth cohorts (MOBAND-CP).

PubMed

Tollånes, Mette C; Strandberg-Larsen, Katrine; Forthun, Ingeborg; Petersen, Tanja Gram; Moster, Dag; Andersen, Anne-Marie Nybo; Stoltenberg, Camilla; Olsen, Jørn; Wilcox, Allen J

2016-09-02

The purpose of MOthers and BAbies in Norway and Denmark cerebral palsy (MOBAND-CP) was to study CP aetiology in a prospective design. MOBAND-CP is a cohort of more than 210 000 children, created as a collaboration between the world's two largest pregnancy cohorts-the Norwegian Mother and Child Cohort study (MoBa) and the Danish National Birth Cohort. MOBAND-CP includes maternal interview/questionnaire data collected during pregnancy and follow-up, plus linked information from national health registries. Initial harmonisation of data from the 2 cohorts has created 140 variables for children and their mothers. In the MOBAND-CP cohort, 438 children with CP have been identified through record linkage with validated national registries, providing by far the largest such sample with prospectively collected detailed pregnancy data. Several studies investigating various hypotheses regarding CP aetiology are currently on-going. Additional data can be harmonised as necessary to meet requirements of new projects. Biological specimens collected during pregnancy and at delivery are potentially available for assay, as are results from assays conducted on these specimens for other projects. The study size allows consideration of CP subtypes, which is rare in aetiological studies of CP. In addition, MOBAND-CP provides a platform within the context of a merged birth cohort of exceptional size that could, after appropriate permissions have been sought, be used for cohort and case-cohort studies of other relatively rare health conditions of infants and children. 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/

Improved design of prodromal Alzheimer's disease trials through cohort enrichment and surrogate endpoints.

PubMed

Macklin, Eric A; Blacker, Deborah; Hyman, Bradley T; Betensky, Rebecca A

2013-01-01

Alzheimer's disease (AD) trials initiated during or before the prodrome are costly and lengthy because patients are enrolled long before clinical symptoms are apparent, when disease progression is slow. We hypothesized that design of such trials could be improved by: 1) selecting individuals at moderate near-term risk of progression to AD dementia (the current clinical standard) and 2) by using short-term surrogate endpoints that predict progression to AD dementia. We used a longitudinal cohort of older, initially non-demented, community-dwelling participants (n = 358) to derive selection criteria and surrogate endpoints and tested them in an independent national data set (n = 6,243). To identify a "mid-risk" subgroup, we applied conditional tree-based survival models to Clinical Dementia Rating (CDR) scale scores and common neuropsychological tests. In the validation cohort, a time-to-AD dementia trial applying these mid-risk selection criteria to a pool of all non-demented individuals could achieve equivalent power with 47% fewer participants than enrolling at random from that pool. We evaluated surrogate endpoints measureable over two years of follow-up based on cross-validated concordance between predictions from Cox models and observed time to AD dementia. The best performing surrogate, rate of change in CDR sum-of-boxes, did not reduce the trial duration required for equivalent power using estimates from the validation cohort, but alternative surrogates with better ability to predict time to AD dementia should be able to do so. The approach tested here might improve efficiency of prodromal AD trials using other potential measures and could be generalized to other diseases with long prodromal phases.

Asbestos and cancer: a cohort followed up to death.

PubMed Central

Enterline, P E; Hartley, J; Henderson, V

1987-01-01

The mortality experience of 1074 white men who retired from a United States asbestos company during the period 1941-67 and who were exposed to asbestos working as production and maintenance employees for the company is reported to the end of 1980 when 88% of this cohort was known to be dead. As noted in earlier reports the mortality for respiratory and gastrointestinal cancer was raised. A more detailed examination of causes of death shows that the excess in gastrointestinal cancer was largely due to a statistically significant excess in stomach cancer. A statistically significant excess was also noted for kidney cancer, cancer of the eye, and non-malignant respiratory disease. Eight deaths from malignant mesothelioma were observed, two of which were peritoneal. Asbestos exposures for these mesothelioma cases were low relative to other members of the cohort. Continuing follow up of this cohort shows a dose response relation for respiratory cancer that has become increasingly linear. Standardised mortality ratios peaked 10 to 15 years after retirement and were relatively constant at around 250 in each five year interval starting in 1950. This excess might have been detected as early as 1960 but certainly by 1965. The mortality experience of this cohort reflects the ultimate effects of asbestos since nearly all of the cohort has now died. PMID:3606968

Comparative analysis of the 2016 ACR-EULAR and the 2002 AECG classification criteria for Sjögren's syndrome: Findings from the NIH cohort.

PubMed

Billings, M; Amin Hadavand, M; Alevizos, I

2018-03-01

The introduction of new classification criteria for Sjögren's syndrome, known as the 2016 American College of Rheumatology/European League against Rheumatism Classification Criteria (ACR-EULAR), created a need for the evaluation of its performance in an external cohort. The purpose of this study was to compare the performance of the 2016 ACR-EULAR classification set with the widely used American-European Consensus Group Classification criteria (AECG) in the cohort at the National Institutes of Health, USA, and to compare the performance of the sets in classifying both primary and secondary Sjögren's syndrome (pSS and sSS). The study cohort at the NIH (N = 1,303) was enrolled for clinical suspicion of SS. Participants were classified as SS, pSS, and sSS according to both classification sets. Performance of 2016 ACR-EULAR and AECG sets was compared holding each as gold standard to the other. Statistical analysis of test diagnostics and agreement between the two sets were undertaken. By the AECG set, 701 were classified as having SS (627 pSS, 74 sSS) and 714 were classified with SS (647 pSS, 67 sSS) by the 2016 ACR-EULAR set. Sensitivity and specificity of the two sets were comparable in classifying SS, pSS, and sSS. There was high agreement between the two sets for classifying SS (κ = 0.79), pSS (κ = 0.81), and sSS (κ = 0.87). The specificity of the 2016 ACR-EULAR set was significantly higher for classifying sSS than pSS, while the sensitivity was similar for the two disease groups. However, this pattern was also exhibited by the AECG set. There was high agreement between the two classification sets with comparable performance diagnostics. There was no evidence of superior performance value by the new 2016 ACR-EULAR set over the AECG set, and the two sets were found to be equivalent. Findings from our cohort indicate that 2016 ACR-EULAR classification could be extended to classification of sSS. Published 2018. This article is a U.S. Government work and

Cohort Profile: The JS High School study (JSHS): a cohort study of Korean adolescents.

PubMed

Choi, Dong Phil; Lee, Joo Young; Kim, Hyeon Chang

2017-04-01

Major aetiologies of atherosclerotic cardiovascular diseases begin in childhood and atherosclerotic vascular abnormalities can be observed among children and adolescents. Adolescent cohort studies have important advantages because they can observe earlier changes in vascular structure and function. The purpose of the JS High School study (JSHS) is to identify biomarkers predicting or indicating early structural and functional vascular change in adolescents. The JSHS is a prospective cohort study of a Korean adolescent population. The target population of the JSHS was first-graders (aged 14 to17 years) at a high school of South Korea. Enrolment and baseline examinations were conducted in years 2007, 2010, 2011 and 2012. Among the total eligible population of 1115 students, 1071 (96.1%) participated in the study and completed all baseline examinations. Informed consent forms were obtained from each participant and his/her parent or guardian. Baseline examinations include: questionnaires on demographics, health behaviours, medical history, and depression symptoms; fasting blood analysis; anthropometric measurement; body impedance analysis; blood pressure measurement; radial artery tonometry; bone densitometry; pulmonary function tests; and carotid ultrasonography. Participants enrolled from 2007 through 2012 were re-examined after 30 months of follow-up, and those who enrolled in 2012 were re-examined after 24 months of follow-up. The corresponding author may be contacted for potential collaboration and data access. © The Author 2015; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.

Cancer and non-cancer mortality among French uranium cycle workers: the TRACY cohort

PubMed Central

Samson, Eric; Piot, Irwin; Zhivin, Sergey; Richardson, David B; Laroche, Pierre; Serond, Ana-Paula; Laurier, Dominique; Laurent, Olivier

2016-01-01

Objectives The health effects of internal contamination by radionuclides, and notably by uranium, are poorly characterised. New cohorts of uranium workers are needed to better examine these effects. This paper analyses for the first time the mortality profile of the French cohort of uranium cycle workers. It considers mortality from cancer and non-cancer causes. Methods The cohort includes workers employed at least 6 months between 1958 and 2006 in French companies involved in the production of nuclear fuel. Vital status and causes of death were collected from French national registries. Workers were followed-up from 1 January 1968 to 31 December 2008. Standardised mortality ratios (SMRs) were computed based on mortality rates for the French general population. Results The cohort includes 12 649 workers (88% men). The average length of follow-up is 27 years and the mean age at the end of the study is 60 years. Large mortality deficits are observed for non-cancer causes of death such as non-cancer respiratory diseases (SMR=0.51 (0.41 to 0.63)) and circulatory diseases (SMR=0.68 (0.62 to 0.74)). A mortality deficit of lower magnitude is also observed for all cancers combined (SMR (95% CI): 0.76 (0.71 to 0.81)). Pleural mesothelioma is elevated (SMR=2.04 (1.19 to 3.27)). Conclusions A healthy worker effect is observed in this new cohort of workers involved in the uranium cycle. Collection of individual information on internal uranium exposure as well as other risk factors is underway, to allow for the investigation of uranium-related risks. PMID:27048635

Lung Cancer Risk from Plutonium: A Pooled Analysis of the Mayak and Sellafield Worker Cohorts.

PubMed

Gillies, Michael; Kuznetsova, Irina; Sokolnikov, Mikhail; Haylock, Richard; O'Hagan, Jackie; Tsareva, Yulia; Labutina, Elena

2017-12-01

In this study, lung cancer risk from occupational plutonium exposure was analyzed in a pooled cohort of Mayak and Sellafield workers, two of the most informative cohorts in the world with detailed plutonium urine monitoring programs. The pooled cohort comprised 45,817 workers: 23,443 Sellafield workers first employed during 1947-2002 with follow-up until the end of 2005 and 22,374 Mayak workers first employed during 1948-1982 with follow-up until the end of 2008. In the pooled cohort 1,195 lung cancer deaths were observed (789 Mayak, 406 Sellafield) but only 893 lung cancer incidences (509 Mayak, 384 Sellafield, due to truncated follow-up in the incidence analysis). Analyses were performed using Poisson regression models, and were based on doses derived from individual radiation monitoring data using an updated dose assessment methodology developed in the study. There was clear evidence of a linear association between cumulative internal plutonium lung dose and risk of both lung cancer mortality and incidence in the pooled cohort. The pooled point estimates of the excess relative risk (ERR) from plutonium exposure for both lung cancer mortality and incidence were within the range of 5-8 per Gy for males at age 60. The ERR estimates in relationship to external gamma radiation were also significantly raised and in the range 0.2-0.4 per Gy of cumulative gamma dose to the lung. The point estimates of risk, for both external and plutonium exposure, were comparable between the cohorts, which suggests that the pooling of these data was valid. The results support point estimates of relative biological effectiveness (RBE) in the range of 10-25, which is in broad agreement with the value of 20 currently adopted in radiological protection as the radiation weighting factor for alpha particles, however, the uncertainty on this value (RBE = 21; 95% CI: 9-178) is large. The results provide direct evidence that the plutonium risks in each cohort are of the same order of magnitude

Pregnancy outcomes in HIV-positive women in Ukraine, 2000-12 (European Collaborative Study in EuroCoord): an observational cohort study.

PubMed

Bagkeris, Emmanouil; Malyuta, Ruslan; Volokha, Alla; Cortina-Borja, Mario; Bailey, Heather; Townsend, Claire L; Thorne, Claire

2015-09-01

Women living with HIV are potentially at increased risk of adverse pregnancy outcomes, due to a range of factors, including immunosuppression, use of combination antiretroviral therapy (ART), and injecting drug use. Rates of mother-to-child transmission of HIV in Ukraine have declined to around 2-4%, but little is known about other pregnancy outcomes in this setting. We used data from an observational prospective cohort study to assess pregnancy outcomes among HIV-positive women in Ukraine. The European Collaborative Study (ECS) in EuroCoord is a continuing cohort study, established in Ukraine in 2000. Eligible women are those with a diagnosis of HIV infection before or during pregnancy (including intrapartum) who deliver liveborn babies at seven sites. Maternal sociodemographic, HIV-related, and delivery (mother and infant) data were collected with study-specific questionnaires. We used Poisson regression models to identify factors associated with preterm delivery (before 37 weeks' gestation) and small weight for gestational age (less than the tenth percentile of weight for gestational age), based on complete cases. Between January, 2000, and July, 2012, data were collected on 8884 HIV-positive mother and liveborn infant pairs. Median maternal age was 26·5 years (IQR 23·1-30·3). 832 (11%) women had WHO stage 3 or 4 HIV and 1474 (17%) had a history of injecting drug use. 7348 (83%) had received antenatal ART. Among 7435 for whom ART type was available, 4396 (50%) had received zidovudine monotherapy and 2949 (33%) combination ART. Preterm delivery was seen in 780 (9%, 95% CI 8-9) of 8860 births overall and in 77 (9%, 7-11) of 889 babies with small size for gestational age. Factors associated with preterm delivery were history of injecting drug use (adjusted risk ratio 1·64, 95% CI 1·38-1·95), no ART (2·94, 2·43-3·57 vs zidovudine monotherapy), antenatal combination ART (1·40, 1·14-1·73 vs zidovudine monotherapy), WHO stage 4 HIV (2·42, 1·71-3·41 vs

The Clinical Research Center for Depression Study: Baseline Characteristics of a Korean Long-Term Hospital-Based Observational Collaborative Prospective Cohort Study

PubMed Central

Kim, Tae-Suk; Jeong, Seung Hee; Kim, Jung-Bum; Lee, Min-Soo; Kim, Jae-Min; Yim, Hyeon-Woo

2011-01-01

Objective The Clinical Research Center for Depression (CRESCEND) study is a 9-year observational collaborative prospective cohort study for the clinical outcomes in participants with depressive disorders in Korea. In this study, we examined the baseline characteristics of the depressive participants as the hospital-based cohort. Methods Participants were assessed using various instruments including the Clinical Global Impression scale, 17-item Hamilton Depression Rating Scale (HDRS-17), Hamilton Anxiety Rating Scale, Brief Psychiatric Rating Scale, Social and Occupational Functioning Assessment Scale, Beck Depression Inventory-Second Edition, Scale for Suicide Ideation, and World Health Organization Quality of Life assessment instruments-abbreviated version. Also, personal histories of medical and psychiatric illnesses and the range of socio-epidemiologic and clinical data were collected from each participant. Results One thousand one hundred eighty three participants were recruited from 18 hospitals. The mean age of the participants was 47.9±15.9 year-old, 74.4% were female, 82.9% had been diagnosed of major depressive disorder, 40.9% were experiencing their first depressive episode, and 21.4% had a past history of suicide attempts. The majority (85.3%) of the participants were moderately to severely ill. The average HDRS-17 was 19.8±6.1. Significant gender differences at baseline were shown in age, education, marriage, employment, religion, and first depressive episode. Conclusion The baseline findings in the CRESCEND study showed some different characteristics of depression in Korea, suggesting a possibility of ethnic and cultural factors in depression. PMID:21519530

A prospective, observational clinical trial of fever reduction to reduce systemic oxygen consumption in the setting of acute brain injury.

PubMed

Hata, J Steven; Shelsky, Constance R; Hindman, Bradley J; Smith, Thomas C; Simmons, Jonathan S; Todd, Michael M

2008-01-01

Fever after acute brain injury appears to be a detrimental factor, associated with impaired neurological outcomes. This study assessed physiological changes in systemic oxygen consumption (VO2) during cutaneous cooling after severe brain injury. This prospective, observational, clinical study evaluated ten, critically ill, brain-injured patients requiring mechanical ventilation with a core body temperature of greater or equal to 38 degrees C. Febrile patients failing to defervesce after acetaminophen underwent indirect calorimetry for a 1-hour baseline period followed by a 4 h cooling period. The Arctic Sun(R) Temperature Management System (Medivance) directed core temperature to a goal of 36 degrees C. The patients had a mean age of 32 years (95% CI 23, 40), Glasgow Coma Scale of 6 (95% CI 5,7), and APACHE 2 score of 19 (95% CI 15, 22), with 8 of 10 patients suffering traumatic brain injuries. The baseline 1-h core temperature was significantly reduced from 38.6 degrees +/- 0.9 to 36.3 degrees +/- 1.2 degrees C (P < 0.0001) over 4 h. Two cohorts were identified based upon the presence or absence of shivering. Within the non-shivering cohort, systemic VO2 was significantly reduced from 415 +/- 123 to 308 +/- 115 ml/min (-27 +/- 18%) (P < 0.05). In contrast, those with shivering showed no significant reduction in VO2, despite significantly decreasing core temperature. The overall percentage change of VCO2 correlated with VO2 (r (2) = 0.91). Fever reduction in acute brain injury appears to significantly reduce systemic VO2, but is highly dependent on shivering control.

Breast-feeding and Infant Hospitalization for Infections: Large Cohort and Sibling Analysis.

PubMed

Størdal, Ketil; Lundeby, Karen M; Brantsæter, Anne L; Haugen, Margaretha; Nakstad, Britt; Lund-Blix, Nicolai A; Stene, Lars C

2017-08-01

Breast-feeding may protect against infections, but its optimal duration remains controversial. We aimed to study the association of the duration of full and any breast-feeding with infections the first 18 months of life. The Norwegian Mother and Child study (MoBa) is a prospective birth cohort which recruited expecting mothers giving birth from 2000 to 2009. We analyzed data from the full cohort (n = 70,511) and sibling sets (n = 21,220) with parental report of breast-feeding and infections. The main outcome measures were the relative risks (RRs) for hospitalization for infections from 0 to 18 months by age at introduction of complementary foods and duration of any breast-feeding. Although we found some evidence for an overall association between longer duration of full breast-feeding and lower risk of hospitalizations for infections, 7.3% of breast-fed children who received complementary foods at 4 to 6 months of age compared to 7.7% of those receiving complementary foods after 6 months were hospitalized (adjusted RR 0.95, 95% confidence interval 0.88-1.03). Higher risk of hospitalization was observed in those breast-fed 6 months or less (10.0%) compared to ≥12 months (7.6%, adjusted RR 1.22, 95% confidence interval 1.14-1.31), but with similar risks for 6 to 11 months versus ≥12 months. Matched sibling analyses, minimizing the confounding from shared maternal factors, showed nonsignificant associations and were generally weaker compared with the cohort analyses. Our results support the recommendation to fully breast-feed for 4 months and to continue breast-feeding beyond 6 months, and suggest that protection against infections is limited to the first 12 months.

Effect of anti-TNF and conventional synthetic disease-modifying anti-rheumatic drug treatment on work disability and clinical outcome in a multicentre observational cohort study of psoriatic arthritis.

PubMed

Tillett, William; Shaddick, Gavin; Jobling, Amelia; Askari, Ayman; Cooper, Annie; Creamer, Paul; Clunie, Gavin; Helliwell, Philip S; James, Jana; Kay, Lesley; Korendowych, Eleanor; Lane, Suzanne; Packham, Jonathon; Shaban, Ragai; Thomas, Matthew L; Williamson, Lyn; McHugh, Neil

2017-04-01

To determine the effect of medical treatment on work disability in patients with active PsA in a real-world setting. Four hundred patients with active PsA commencing or switching to anti-TNF or conventional synthetic DMARD (csDMARD) were recruited to a multicentre UK prospective observational cohort study. Work disability was measured using the work productivity and activity-specific health problem instrument and peripheral joint activity was measured with the disease activity in PsA composite measure. Four hundred patients were recruited, of whom 229 (57.25%) were working (of any age). Sixty-two patients of working age (24%) were unemployed. At 6 months there was a 10% improvement in presenteeism ( P = 0.007) and a 15% improvement in work productivity ( P = 0.001) among working patients commenced on csDMARDs ( n = 164) vs a larger and more rapid 30% improvement in presenteeism ( P < 0.001) and 40% improvement in work productivity ( P < 0.001) among those commenced on anti-TNF therapy ( n = 65). Clinical response was poor among patients commenced on a csDMARD ( n = 272), with an 8.4 point improvement in disease activity in PsA ( P < 0.001) vs those commenced on anti-TNF therapy ( n = 121), who had a 36.8 point improvement ( P < 0.001). We report significant and clinically meaningful improvements in both work disability and clinical outcomes after commencement of anti-TNF therapy in a real-world setting. Improvements in all outcomes among those commencing csDMARDs were slower and of a smaller magnitude. © The Author 2016. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Body mass index increases risk of colorectal adenomas in men with Lynch syndrome: the GEOLynch cohort study.

PubMed

Botma, Akke; Nagengast, Fokko M; Braem, Marieke G M; Hendriks, Jan C M; Kleibeuker, Jan H; Vasen, Hans F A; Kampman, Ellen

2010-10-01

High body mass index (BMI) is an established risk factor for sporadic colorectal cancer. Still, the influence of BMI on hereditary colorectal cancer (eg, Lynch syndrome [LS]), is unknown. The objective of this study was to assess whether BMI is associated with colorectal adenoma occurrence in persons with LS. A prospective cohort study of 486 patients with LS was conducted. Cox regression models with robust sandwich estimates controlling for age, sex, extent of colon surgery, smoking, and alcohol intake were used to evaluate associations between BMI, height, weight, weight change, and risk of colorectal adenomas. Analyses were performed separately for those without (incident cohort; n = 243) and those with (prevalent cohort; n = 243) a history of colorectal cancer neoplasms at baseline. A statistically significant association between current overweight (≥ 25 kg/m(2)) and developing colorectal adenomas was seen among men in the incident cohort (overweight v normal weight hazard ratio [HR], 8.72; 95% CI, 2.06 to 36.96). This association was not observed among women (overweight v normal weight HR, 0.75; 95% CI, 0.19 to 3.07), nor was it observed in the prevalent cohort. In the incident cohort, height was statistically significantly associated with a decreased risk of adenomatous polyps among men (per 5 cm HR, 0.43; 95% CI, 0.23 to 0.83), but the association between weight and adenomatous polyps among men was of marginal significance (per 5 kg HR, 1.17; 95% CI, 1.00 to 1.37). No statistically significant associations were observed among women in either the incident cohort or the prevalent cohort. Excess body weight increased the risk of incident colorectal adenomas in people with LS. This increased risk was seen only in men.

Cohort profile: the German ClinSurv HIV project--a multicentre open clinical cohort study supplementing national HIV surveillance.

PubMed

Bätzing-Feigenbaum, J; Kollan, C; Kühne, A; Matysiak-Klose, D; Gunsenheimer-Bartmeyer, B; Hamouda, O

2011-05-01

New forms of HIV/AIDS therapy require new surveillance instruments to meet shifting public health demands. The Clinical Surveillance of HIV Disease (ClinSurv HIV) project was established in 1999 as a collaboration between major HIV treatment centres in Germany and the Robert Koch Institute (RKI). The project contributes to national HIV surveillance and focuses on the changing epidemiology of HIV/AIDS after the introduction of new therapies in 1995. ClinSurv HIV is designed as an open multicentre observational cohort study of HIV-infected patients. Anonymized data on diagnoses, treatment and laboratory parameters are collected in a standardized format. Data are currently sampled biannually via 11 centres specializing in HIV diagnosis and care within the legal framework of the German Protection against Infection Act [Infektionsschutzgesetz (IfSG)]. A total of 14874 patients were enrolled in the study by 30 June 2009. Of these, 10221 patients (68.7%) were enrolled after 1 January 1999 and 6006 patients (40.4%) were known to have been diagnosed as positive for HIV before 1999. Evaluation indicators, such as the number of newly enrolled patients per half-year period, loss to follow-up, completeness of data per case, availability of data per possible clinical contact, and internal quality control parameters, show a very stable evolution in the cohort, which although open, can be observed. Comparison with the national HIV surveillance data suggests a high degree of representativeness according to major demographic variables. Bearing in mind the obvious strengths and weaknesses discussed, the German ClinSurv HIV cohort provides a broad range of research opportunities in the field of HIV/AIDS both within Germany and in international collaborative research.

Maternal caffeine intake during pregnancy and childhood growth and overweight: results from a large Norwegian prospective observational cohort study

PubMed Central

Botton, Jérémie; Brantsæter, Anne-Lise; Haugen, Margaretha; Alexander, Jan; Meltzer, Helle Margrete; Bacelis, Jonas; Elfvin, Anders; Jacobsson, Bo; Sengpiel, Verena

2018-01-01

Objectives To study the association between maternal caffeine intake during pregnancy and the child’s weight gain and overweight risk up to 8 years. Design Prospective nationwide pregnancy cohort. Setting The Norwegian Mother and Child Cohort Study. Participants A total of 50 943 mothers recruited from 2002 to 2008 and their children, after singleton pregnancies, with information about average caffeine intake assessed at mid-pregnancy. Outcome measure Child’s body size information at 11 age points from 6 weeks to 8 years. We defined excess growth in infancy as a WHO weight gain z-score of >0.67 from birth to age 1 year, and overweight according to the International Obesity Task Force. We used a growth model to assess individual growth trajectories. Results Compared with pregnant women with low caffeine intake (<50 mg/day, 46%), women with average (50–199 mg/day, 44%), high (≥200–299 mg/day, 7%) and very high (≥300 mg/day, 3%) caffeine intakes had an increased risk of their child experiencing excess growth in infancy, after adjustment for confounders (OR=1.15, 95% CI 1.09 to 1.22, OR=1.30, 95% CI 1.16 to 1.45, OR=1.66, 95% CI 1.42 to 1.93, respectively). In utero exposure to any caffeine was associated with higher risk of overweight at age 3 years and 5 years, while the association persisted at 8 years, only for very high exposures. Any caffeine intake was associated with increased body mass index from infancy to childhood. Children prenatally exposed to caffeine intake >200 mg/day had consistently higher weight. Very high caffeine exposures were associated with higher weight gain velocity from infancy to age 8 years. Conclusion Any caffeine consumption during pregnancy is associated with a higher risk of excess infant growth and of childhood overweight, mainly at preschool ages. Maternal caffeine intake may modify the overall weight growth trajectory of the child from birth to 8 years. This study adds supporting evidence for the

An empirical comparison of Markov cohort modeling and discrete event simulation in a capacity-constrained health care setting.

PubMed

Standfield, L B; Comans, T A; Scuffham, P A

2017-01-01

To empirically compare Markov cohort modeling (MM) and discrete event simulation (DES) with and without dynamic queuing (DQ) for cost-effectiveness (CE) analysis of a novel method of health services delivery where capacity constraints predominate. A common data-set comparing usual orthopedic care (UC) to an orthopedic physiotherapy screening clinic and multidisciplinary treatment service (OPSC) was used to develop a MM and a DES without (DES-no-DQ) and with DQ (DES-DQ). Model results were then compared in detail. The MM predicted an incremental CE ratio (ICER) of $495 per additional quality-adjusted life-year (QALY) for OPSC over UC. The DES-no-DQ showed OPSC dominating UC; the DES-DQ generated an ICER of $2342 per QALY. The MM and DES-no-DQ ICER estimates differed due to the MM having implicit delays built into its structure as a result of having fixed cycle lengths, which are not a feature of DES. The non-DQ models assume that queues are at a steady state. Conversely, queues in the DES-DQ develop flexibly with supply and demand for resources, in this case, leading to different estimates of resource use and CE. The choice of MM or DES (with or without DQ) would not alter the reimbursement of OPSC as it was highly cost-effective compared to UC in all analyses. However, the modeling method may influence decisions where ICERs are closer to the CE acceptability threshold, or where capacity constraints and DQ are important features of the system. In these cases, DES-DQ would be the preferred modeling technique to avoid incorrect resource allocation decisions.

Cohort profile: cerebral palsy in the Norwegian and Danish birth cohorts (MOBAND-CP)

PubMed Central

Tollånes, Mette C; Strandberg-Larsen, Katrine; Forthun, Ingeborg; Petersen, Tanja Gram; Moster, Dag; Andersen, Anne-Marie Nybo; Stoltenberg, Camilla; Olsen, Jørn; Wilcox, Allen J

2016-01-01

Purpose The purpose of MOthers and BAbies in Norway and Denmark cerebral palsy (MOBAND-CP) was to study CP aetiology in a prospective design. Participants MOBAND-CP is a cohort of more than 210 000 children, created as a collaboration between the world's two largest pregnancy cohorts—the Norwegian Mother and Child Cohort study (MoBa) and the Danish National Birth Cohort. MOBAND-CP includes maternal interview/questionnaire data collected during pregnancy and follow-up, plus linked information from national health registries. Findings to date Initial harmonisation of data from the 2 cohorts has created 140 variables for children and their mothers. In the MOBAND-CP cohort, 438 children with CP have been identified through record linkage with validated national registries, providing by far the largest such sample with prospectively collected detailed pregnancy data. Several studies investigating various hypotheses regarding CP aetiology are currently on-going. Future plans Additional data can be harmonised as necessary to meet requirements of new projects. Biological specimens collected during pregnancy and at delivery are potentially available for assay, as are results from assays conducted on these specimens for other projects. The study size allows consideration of CP subtypes, which is rare in aetiological studies of CP. In addition, MOBAND-CP provides a platform within the context of a merged birth cohort of exceptional size that could, after appropriate permissions have been sought, be used for cohort and case-cohort studies of other relatively rare health conditions of infants and children. PMID:27591025

On Fuzzy Sets and Rough Sets from the Perspective of Indiscernibility

NASA Astrophysics Data System (ADS)

Chakraborty, Mihir K.

The category theoretic approach of Obtułowicz to Pawlak's rough sets has been reintroduced in a somewhat modified form. A generalization is rendered to this approach that has been motivated by the notion of rough membership function. Thus, a link is established between rough sets and L-fuzzy sets for some special lattices. It is shown that a notion of indistinguishability lies at the root of vagueness. This observation in turn gives a common ground to the theories of rough sets and fuzzy sets.

External Validation of the Updated Partin Tables in a Cohort of French and Italian Men

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

Bhojani, Naeem; Department of Urology, University of Montreal, Montreal, PQ; Salomon, Laurent

2009-02-01

Purpose: To test the discrimination and calibration properties of the newly developed 2007 Partin Tables in two European cohorts with localized prostate cancer. Methods: Data on clinical and pathologic characteristics were obtained for 1,064 men treated with radical prostatectomy at the Creteil University Health Center in France (n = 839) and at the Milan University Vita-Salute in Italy (n = 225). Overall discrimination was assessed with receiver operating characteristic curve analysis, which quantified the accuracy of stage predictions for each center. Calibration plots graphically explored the relationship between predicted and observed rates of extracapsular extension (ECE), seminal vesicle invasion (SVI)more » and lymph node invasion (LNI). Results: The rates of ECE, SVI, and LNI were 28%, 14%, and 2% in the Creteil cohort vs. 11%, 5%, and 5% in the Milan cohort. In the Creteil cohort, the accuracy of ECE, SVI, and LNI prediction was 61%, 71%, and 82% vs. 66%, 92% and 75% for the Milan cohort. Important departures were recorded between Partin Tables' predicted and observed rates of ECE, SVI, and LNI within both cohorts. Conclusions: The 2007 Partin Tables demonstrated worse performance in European men than they originally did in North American men. This indicates that predictive models need to be externally validated before their implementation into clinical practice.« less

Herd effect from influenza vaccination in non-healthcare settings: a systematic review of randomised controlled trials and observational studies

PubMed Central

Mertz, Dominik; Fadel, Shaza A.; Lam, Po-Po; Tran, Dat; Srigley, Jocelyn A; Asner, Sandra A; Science, Michelle; Kuster, Stefan P; Nemeth, Johannes; Johnstone, Jennie; Ortiz, Justin R; Loeb, Mark

2016-01-01

Influenza vaccination programmes are assumed to have a herd effect and protect contacts of vaccinated persons from influenza virus infection. We searched MEDLINE, EMBASE, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), Global Health and the Cochrane Central Register of Controlled Trials (CENTRAL) from inception to March 2014 for studies assessing the protective effect of influenza vaccination vs no vaccination on influenza virus infections in contacts. We calculated odds ratios (ORs) and 95% confidence intervals (CIs) using a random-effects model. Of 43,082 screened articles, nine randomised controlled trials (RCTs) and four observational studies were eligible. Among the RCTs, no statistically significant herd effect on the occurrence of influenza in contacts could be found (OR: 0.62; 95% CI: 0.34–1.12). The one RCT conducted in a community setting, however, showed a significant effect (OR: 0.39; 95% CI: 0.26–0.57), as did the observational studies (OR: 0.57; 95% CI: 0.43–0.77). We found only a few studies that quantified the herd effect of vaccination, all studies except one were conducted in children, and the overall evidence was graded as low. The evidence is too limited to conclude in what setting(s) a herd effect may or may not be achieved. PMID:27784531

Site-specific cancer risk in the Baltic cohort of Chernobyl cleanup workers, 1986-2007.

PubMed

Rahu, Kaja; Hakulinen, Timo; Smailyte, Giedre; Stengrevics, Aivars; Auvinen, Anssi; Inskip, Peter D; Boice, John D; Rahu, Mati

2013-09-01

To assess site-specific cancer risk in the Baltic cohort of Chernobyl cleanup workers, 1986-2007. The Baltic cohort includes 17,040 men from Estonia, Latvia and Lithuania who participated in the environmental cleanup after the accident at the Chernobyl Nuclear Power Station in 1986-1991 and who were followed up for cancer incidence until the end of 2007. Cancer cases diagnosed in the cohort and in the male population of each country were identified from the respective national cancer registers. The proportional incidence ratio (PIR) with 95% confidence interval (CI) was used to estimate the site-specific cancer risk in the cohort. For comparison and as it was possible, the site-specific standardised incidence ratio (SIR) was calculated for the Estonian sub-cohort, which was not feasible for the other countries. Overall, 756 cancer cases were reported during 1986-2007. A higher proportion of thyroid cancers in relation to the male population was found (PIR=2.76; 95%CI 1.63-4.36), especially among those who started their mission shortly after the accident, in April-May 1986 (PIR=6.38; 95%CI 2.34-13.89). Also, an excess of oesophageal cancers was noted (PIR=1.52; 95% CI 1.06-2.11). No increased PIRs for leukaemia or radiation-related cancer sites combined were observed. PIRs and SIRs for the Estonian sub-cohort demonstrated the same site-specific cancer risk pattern. Consistent evidence of an increase in radiation-related cancers in the Baltic cohort was not observed with the possible exception of thyroid cancer, where conclusions are hampered by known medical examination including thyroid screening among cleanup workers. Copyright © 2013 Elsevier Ltd. All rights reserved.

Newborn literacy program effective in increasing maternal engagement in literacy activities: an observational cohort study.

PubMed

Veldhuijzen van Zanten, Stephanie; Coates, Chrystal; Hervas-Malo, Marilou; McGrath, Patrick J

2012-07-16

Literacy is important for success in school and in adulthood. Book-gift programs at birth exist to help develop these foundations early on. The effectiveness of the Read to Me! Nova Scotia Family Literacy Program (a program where books and literacy materials are given to families in hospital when their baby is born) on the duration and frequency with which mothers engage in reading and other literacy based activities with their newborns was assessed. An observational cohort study design was used. Mothers of babies who received the Read to Me! package in Nova Scotia born between January-August 2006 made up the intervention group (N = 1051). Mothers of babies born in Prince Edward Island between December 2006 and March 2008 made up the control group (N = 279) and did not receive any literacy package when their baby was born. A phone questionnaire was conducted consisting of questions regarding frequency and duration of maternal engagement in language and literacy-based activities with their infants. These activities included reading, singing, talking, listening to CDs and the radio and watching TV. Babies were aged 0-10 months at the time of the interview. Mothers who received the Read to Me! literacy package spent significantly more time reading to their babies, 17.9 ± 17.6 min/day compared to controls 12.6 ± 10.7 min/day, (p < 0.0001). Read to Me! may be an inexpensive, easy to administer and effective intervention which results in increased shared reading of mothers and their newborns.

Mortality among three refinery/petrochemical plant cohorts. II. Retirees.

PubMed

Gamble, J F; Lewis, R J; Jorgensen, G

2000-07-01

This study updates mortality data for 6238 retirees from three refinery/petrochemical plants. Almost 90% of the cohort was deceased. Deaths from all causes (standardized mortality ratio, 104; 95% confidence interval, 102 to 107) and all cancers (standardized mortality ratio, 109; 95% confidence interval, 102 to 116) were elevated. Increased deaths due to kidney cancer, mesothelioma, and the category of other lymphohemopoietic cancers also were observed. The rate of leukemia was not increased. There was little internal or external consistency to support an occupational relationship for kidney cancer, but findings for mesothelioma and other lymphohemopoietic cancers are consistent with reports for other petroleum cohorts. Analyses by age indicated significantly higher all-cause mortality rates among persons retiring before age 65. The results suggest that continued surveillance of mesothelioma and lymphohemopoietic cancer malignancies in younger workers with more contemporary exposures may be warranted. Furthermore, age at retirement should be considered when analyzing occupational cohorts.

Towards an integrated set of surface meterological observations for climate science and applications

NASA Astrophysics Data System (ADS)

Dunn, Robert; Thorne, Peter

2017-04-01

We cannot predict what is not observed, and we cannot analyse what is not archived. To meet current scientific and societal demands, as well as future requirements for climate services, it is vital that the management and curation of land-based meteorological data holdings is improved. A comprehensive global set of data holdings, of known provenance, integrated across both climate variable and timescale are required to meet the wide range of user needs. Presently, the land-based holdings are highly fractured into global, region and national holdings for different variables and timescales, from a variety of sources, and in a mixture of formats. We present a high level overview, based on broad community input, of the steps that are required to bring about this integration and progress towards such a database. Any long-term, international, program creating such an integrated database will transform the our collective ability to provide societally relevant research, analysis and predictions across the globe.

Evaluation of physiotherapy in a prospective cohort of early axial spondyloarthritis. Data from the DESIR cohort.

PubMed

Escalas, Cécile; Dalichampt, Marie; Dougados, Maxime; Poiraudeau, Serge

2016-03-01

To evaluate the effect of physiotherapy on functional limitation in an observational cohort of early axial spondyloarthritis. prospective population-based cohort study. 708 patients with early axial spondyloarthritis between 2007 and 2010 naive of TNF blockers. early physiotherapy defined by at least eight supervised sessions of physical therapy during the first six months. the primary outcome was functional improvement defined by a relative improvement of at least 20% in BASFI at six months. Secondary outcomes were improvement in BASFI at one and two years and ASAS20 response criteria at six months. a propensity score of having physiotherapy was developed and multivariate analysis using propensity score weighting were used to assess the effect of physiotherapy on outcome. Overall, 166 (24%) patients had physiotherapy during the first six months. After using propensity score weighting, there was no functional improvement on the primary outcome in patients treated with early physical therapy (relative risk [IC95%]: 1.15 [0.91-1.45]). No differences were observed on secondary outcomes (relative risk [IC95%]: 0.94 [0.80-1.11]). It seems there is no functional benefit for patients with early spondyloarthritis to be treated early by physiotherapy in daily practice, even though the efficacy of physiotherapy has been shown in several randomized controlled studies. Copyright © 2015 Société française de rhumatologie. Published by Elsevier SAS. All rights reserved.

Dutch outcome in implantable cardioverter-defibrillator therapy (DO-IT): registry design and baseline characteristics of a prospective observational cohort study to predict appropriate indication for implantable cardioverter-defibrillator.

PubMed

van Barreveld, M; Dijkgraaf, M G W; Hulleman, M; Boersma, L V A; Delnoy, P P H M; Meine, M; Tuinenburg, A E; Theuns, D A M J; van der Voort, P H; Kimman, G P; Buskens, E; Tijssen, J P G; Bruinsma, N; Verstraelen, T E; Zwinderman, A H; van Dessel, P H F M; Wilde, A A M

2017-10-01

Implantable cardioverter-defibrillators (ICDs) are widely used for the prevention of sudden cardiac death. At present, both clinical benefit and cost-effectiveness of ICD therapy in primary prevention patients are topics of discussion, as only a minority of these patients will eventually receive appropriate ICD therapy. The DO-IT Registry is a nationwide prospective cohort with a target enrolment of 1,500 primary prevention ICD patients with reduced left ventricular function in a setting of structural heart disease. The primary outcome measures are death and appropriate ICD therapy for ventricular tachyarrhythmias. Secondary outcome measures are inappropriate ICD therapy, death of any cause, hospitalisation for ICD related complications and for cardiovascular reasons. As of December 2016, data on demographic, clinical, and ICD characteristics of 1,468 patients have been collected. Follow-up will continue up to 24 months after inclusion of the last patient. During follow-up, clinical and ICD data are collected based on the normal follow-up of these patients, assuming ICD interrogations take place every six months and clinical follow-up is once a year. At baseline, the mean age was 66 (standard deviation [SD] 10) years and 27% were women. The DO-IT Registry represents a real-world nationwide cohort of patients receiving ICDs for primary prevention of sudden cardiac death with reduced left ventricular function in a setting of structural heart disease. The registry investigates the efficacy of the current practice and aims to develop prediction rules to identify subgroups who will not (sufficiently) benefit from ICD implantation and to provide results regarding costs and budget impact of targeted supply of primary preventions ICDs.

Antiepileptic drugs and the risk of ischaemic stroke and myocardial infarction: a population-based cohort study

PubMed Central

Renoux, Christel; Dell'Aniello, Sophie; Saarela, Olli; Filion, Kristian B; Boivin, Jean-François

2015-01-01

Objectives Hepatic enzyme-inducing antiepileptic drugs (AEDs) increase serum lipid levels and other atherogenic markers via the induction of cytochrome P450 and may therefore increase the risk of vascular events. We sought to assess the risk of ischaemic stroke and myocardial infarction (MI) according to AED enzymatic properties. Design Population-based cohort study with nested case–control analysis. Setting 650 general practices in the UK contributing to the Clinical Practice Research Datalink. Participants A cohort of 252 407 incident AED users aged 18 or older between January 1990 and April 2013. For each case of ischaemic stroke or MI, up to 10 controls were randomly selected among the cohort members in the risk sets defined by the case and matched on age, sex, indication for AED, calendar time and duration of follow-up. Interventions Current use of enzyme-inducing and enzyme-inhibiting AEDs compared with non-inducing AEDs. Primary outcome measures Incidence rate ratios (RRs) of ischaemic stroke and MI. Results 5069 strokes and 3636 MIs were identified during follow-up. Inducing AEDs use was associated with a small increased risk of ischaemic stroke (RR=1.16, 95% CI 1.02 to 1.33) relative to non-inducing AEDs, most likely due to residual confounding. However, current use of inducing AEDs for ≥24 months was associated with a 46% increased risk of MI (RR=1.46, 95% CI 1.15 to 1.85) compared with the same duration of non-inducing AED, corresponding to a risk difference of 1.39/1000 (95% CI 0.33 to 2.45) persons per year. Current use of inhibiting AED was associated with a decreased risk of MI (RR=0.81, 95% CI 0.66 to 1.00). Conclusions The use of enzyme-inducing AEDs was not associated with an increased risk of ischaemic stroke; a small increase of MI with prolonged use was observed. In contrast, use of inhibiting AEDs was associated with a decreased risk of MI. PMID:26270948

Symptom clusters predict mortality among dialysis patients in Norway: a prospective observational cohort study.

PubMed

Amro, Amin; Waldum, Bård; von der Lippe, Nanna; Brekke, Fredrik Barth; Dammen, Toril; Miaskowski, Christine; Os, Ingrid

2015-01-01

Patients with end-stage renal disease on dialysis have reduced survival rates compared with the general population. Symptoms are frequent in dialysis patients, and a symptom cluster is defined as two or more related co-occurring symptoms. The aim of this study was to explore the associations between symptom clusters and mortality in dialysis patients. In a prospective observational cohort study of dialysis patients (n = 301), Kidney Disease and Quality of Life Short Form and Beck Depression Inventory questionnaires were administered. To generate symptom clusters, principal component analysis with varimax rotation was used on 11 kidney-specific self-reported physical symptoms. A Beck Depression Inventory score of 16 or greater was defined as clinically significant depressive symptoms. Physical and mental component summary scores were generated from Short Form-36. Multivariate Cox regression analysis was used for the survival analysis, Kaplan-Meier curves and log-rank statistics were applied to compare survival rates between the groups. Three different symptom clusters were identified; one included loading of several uremic symptoms. In multivariate analyses and after adjustment for health-related quality of life and depressive symptoms, the worst perceived quartile of the "uremic" symptom cluster independently predicted all-cause mortality (hazard ratio 2.47, 95% CI 1.44-4.22, P = 0.001) compared with the other quartiles during a follow-up period that ranged from four to 52 months. The two other symptom clusters ("neuromuscular" and "skin") or the individual symptoms did not predict mortality. Clustering of uremic symptoms predicted mortality. Assessing co-occurring symptoms rather than single symptoms may help to identify dialysis patients at high risk for mortality. Copyright © 2015 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.

Prenatal Treatment for Serious Neurological Sequelae of Congenital Toxoplasmosis: An Observational Prospective Cohort Study

PubMed Central

Cortina-Borja, Mario; Tan, Hooi Kuan; Wallon, Martine; Paul, Malgorzata; Prusa, Andrea; Buffolano, Wilma; Malm, Gunilla; Salt, Alison; Freeman, Katherine; Petersen, Eskild; Gilbert, Ruth E.

2010-01-01

Background The effectiveness of prenatal treatment to prevent serious neurological sequelae (SNSD) of congenital toxoplasmosis is not known. Methods and Findings Congenital toxoplasmosis was prospectively identified by universal prenatal or neonatal screening in 14 European centres and children were followed for a median of 4 years. We evaluated determinants of postnatal death or SNSD defined by one or more of functional neurological abnormalities, severe bilateral visual impairment, or pregnancy termination for confirmed congenital toxoplasmosis. Two-thirds of the cohort received prenatal treatment (189/293; 65%). 23/293 (8%) fetuses developed SNSD of which nine were pregnancy terminations. Prenatal treatment reduced the risk of SNSD. The odds ratio for prenatal treatment, adjusted for gestational age at maternal seroconversion, was 0.24 (95% Bayesian credible intervals 0.07–0.71). This effect was robust to most sensitivity analyses. The number of infected fetuses needed to be treated to prevent one case of SNSD was three (95% Bayesian credible intervals 2–15) after maternal seroconversion at 10 weeks, and 18 (9–75) at 30 weeks of gestation. Pyrimethamine-sulphonamide treatment did not reduce SNSD compared with spiramycin alone (adjusted odds ratio 0.78, 0.21–2.95). The proportion of live-born infants with intracranial lesions detected postnatally who developed SNSD was 31.0% (17.0%–38.1%). Conclusion The finding that prenatal treatment reduced the risk of SNSD in infected fetuses should be interpreted with caution because of the low number of SNSD cases and uncertainty about the timing of maternal seroconversion. As these are observational data, policy decisions about screening require further evidence from a randomized trial of prenatal screening and from cost-effectiveness analyses that take into account the incidence and prevalence of maternal infection. Please see later in the article for the Editors' Summary PMID:20967235

Visit-to-visit SBP variability and cardiovascular disease in a multiethnic primary care setting: 10-year retrospective cohort study.

PubMed

Chia, Yook Chin; Ching, Siew Mooi; Lim, Hooi Min

2017-05-01

The current study aims to determine the relationship of long-term visit-to-visit variability of SBP to cardiovascular disease (CVD) in a multiethnic primary care setting. This is a retrospective study of a cohort of 807 hypertensive patients over a period of 10 years. Three-monthly clinic blood pressure readings were used to derive blood pressure variability (BPV), and CVD events were captured from patient records. Mean age at baseline was 57.2 ± 9.8 years with 63.3% being women. The BPV and mean SBP over 10 years were 14.7 ± 3.5 and 142 ± 8 mmHg, respectively. Prevalence of cardiovascular event was 13%. In multivariate logistic regression analysis, BPV was the predictor of CVD events, whereas the mean SBP was not independently associated with cardiovascular events in this population. Those with lower SBP and lower BPV had fewer cardiovascular events than those with the same low mean SBP but higher BPV (10.5 versus 12.8%). Similarly those with higher mean SBP but lower BPV also had fewer cardiovascular events than those with the same high mean and higher BPV (11.6 versus 16.7%). Other variables like being men, diabetes and Indian compared with Chinese are more likely to be associated with cardiovascular events. BPV is associated with an increase in CVD events even in those who have achieved lower mean SBP. Thus, we should prioritize not only control of SBP levels but also BPV to reduce CVD events further.

Effectiveness and Value of Prophylactic 5-Layer Foam Sacral Dressings to Prevent Hospital-Acquired Pressure Injuries in Acute Care Hospitals: An Observational Cohort Study.

PubMed

Padula, William V

The purpose of this study was to examine the effectiveness and value of prophylactic 5-layer foam sacral dressings to prevent hospital-acquired pressure injury rates in acute care settings. Retrospective observational cohort. We reviewed records of adult patients 18 years or older who were hospitalized at least 5 days across 38 acute care hospitals of the University Health System Consortium (UHC) and had a pressure injury as identified by Patient Safety Indicator #3 (PSI-03). All facilities are located in the United States. We collected longitudinal data pertaining to prophylactic 5-layer foam sacral dressings purchased by hospital-quarter for 38 academic medical centers between 2010 and 2015. Longitudinal data on acute care, hospital-level patient outcomes (eg, admissions and PSI-03 and pressure injury rate) were queried through the UHC clinical database/resource manager from the Johns Hopkins Medicine portal. Data on volumes of dressings purchased per UHC hospital were merged with UHC data. Mixed-effects negative binomial regression was used to test the longitudinal association of prophylactic foam sacral dressings on pressure injury rates, adjusted for hospital case-mix and Medicare payments rules. Significant pressure injury rate reductions in US acute care hospitals between 2010 and 2015 were associated with the adoption of prophylactic 5-layer foam sacral dressings within a prevention protocol (-1.0 cases/quarter; P = .002) and changes to Medicare payment rules in 2014 (-1.13 cases/quarter; P = .035). Prophylactic 5-layer foam sacral dressings are an effective component of a pressure injury prevention protocol. Hospitals adopting these technologies should expect good value for use of these products.

Cancer and non-cancer mortality among French uranium cycle workers: the TRACY cohort.

PubMed

Samson, Eric; Piot, Irwin; Zhivin, Sergey; Richardson, David B; Laroche, Pierre; Serond, Ana-Paula; Laurier, Dominique; Laurent, Olivier

2016-04-05

The health effects of internal contamination by radionuclides, and notably by uranium, are poorly characterised. New cohorts of uranium workers are needed to better examine these effects. This paper analyses for the first time the mortality profile of the French cohort of uranium cycle workers. It considers mortality from cancer and non-cancer causes. The cohort includes workers employed at least 6 months between 1958 and 2006 in French companies involved in the production of nuclear fuel. Vital status and causes of death were collected from French national registries. Workers were followed-up from 1 January 1968 to 31 December 2008. Standardised mortality ratios (SMRs) were computed based on mortality rates for the French general population. The cohort includes 12,649 workers (88% men). The average length of follow-up is 27 years and the mean age at the end of the study is 60 years. Large mortality deficits are observed for non-cancer causes of death such as non-cancer respiratory diseases (SMR=0.51 (0.41 to 0.63)) and circulatory diseases (SMR=0.68 (0.62 to 0.74)). A mortality deficit of lower magnitude is also observed for all cancers combined (SMR (95% CI): 0.76 (0.71 to 0.81)). Pleural mesothelioma is elevated (SMR=2.04 (1.19 to 3.27)). A healthy worker effect is observed in this new cohort of workers involved in the uranium cycle. Collection of individual information on internal uranium exposure as well as other risk factors is underway, to allow for the investigation of uranium-related risks. 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/

Clinical application of the Melbourne risk prediction tool in a high-risk upper abdominal surgical population: an observational cohort study.

PubMed

Parry, S; Denehy, L; Berney, S; Browning, L

2014-03-01

(1) To determine the ability of the Melbourne risk prediction tool to predict a pulmonary complication as defined by the Melbourne Group Scale in a medically defined high-risk upper abdominal surgery population during the postoperative period; (2) to identify the incidence of postoperative pulmonary complications; and (3) to examine the risk factors for postoperative pulmonary complications in this high-risk population. Observational cohort study. Tertiary Australian referral centre. 50 individuals who underwent medically defined high-risk upper abdominal surgery. Presence of postoperative pulmonary complications was screened daily for seven days using the Melbourne Group Scale (Version 2). Postoperative pulmonary risk prediction was calculated according to the Melbourne risk prediction tool. (1) Melbourne risk prediction tool; and (2) the incidence of postoperative pulmonary complications. Sixty-six percent (33/50) underwent hepatobiliary or upper gastrointestinal surgery. Mean (SD) anaesthetic duration was 377.8 (165.5) minutes. The risk prediction tool classified 84% (42/50) as high risk. Overall postoperative pulmonary complication incidence was 42% (21/50). The tool was 91% sensitive and 21% specific with a 50% chance of correct classification. This is the first study to externally validate the Melbourne risk prediction tool in an independent medically defined high-risk population. There was a higher incidence of pulmonary complications postoperatively observed compared to that previously reported. Results demonstrated poor validity of the tool in a population already defined medically as high risk and when applied postoperatively. This observational study has identified several important points to consider in future trials. Copyright © 2013 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.

The incidence of severe hypoglycaemia in pregnant women with type 1 diabetes mellitus can be reduced with unchanged HbA1c levels and pregnancy outcomes in a routine care setting.

PubMed

Ringholm, Lene; Secher, A L; Pedersen-Bjergaard, U; Thorsteinsson, B; Andersen, H U; Damm, P; Mathiesen, E R

2013-08-01

To investigate whether the incidence of severe hypoglycaemia in pregnant women with type 1 diabetes can be reduced without deteriorating HbA1c levels or pregnancy outcomes in a routine care setting. Two cohorts (2004-2006; n=108 and 2009-2011; n=104) were compared. In between the cohorts a focused intervention including education of caregivers and patients in preventing hypoglycaemia was implemented. Women were included at median 8 (range 5-13) weeks. Severe hypoglycaemia (requiring assistance from others) was prospectively reported in structured interviews. In the first vs. second cohort, severe hypoglycaemia during pregnancy occurred in 45% vs. 23%, p=0.0006, corresponding to incidences of 2.5 vs. 1.6 events/patient-year, p=0.04. Unconsciousness and/or convulsions occurred at 24% vs. 8% of events. Glucagon and/or glucose injections were given at 15% vs. 5% of events. At inclusion HbA1c was comparable between the cohorts while in the second cohort fewer women reported impaired hypoglycaemia awareness (56% vs. 36%, p=0.0006), insulin dose in women on multiple daily injections was lower (0.77 IU/kg (0.4-1.7) vs. 0.65 (0.2-1.4), p=0.0006) and more women were on insulin analogues (rapid-acting 44% vs. 97%, p<0.0001; long-acting 6% vs. 76%, p<0.0001) and insulin pumps (5% vs. 23%, p<0.0001). Pregnancy outcomes were similar in the two cohorts. A 36% reduction in the incidence of severe hypoglycaemia in pregnancy with unchanged HbA1c levels and pregnancy outcomes was observed after implementation of focused intervention against severe hypoglycaemia in a routine care setting. Improved insulin treatment, increased health professional education and fewer women with impaired hypoglycaemia awareness may contribute. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Improved design of prodromal Alzheimer’s disease trials through cohort enrichment and surrogate endpoints

PubMed Central

Macklin, Eric A.; Blacker, Deborah; Hyman, Bradley T.; Betensky, Rebecca A.

2013-01-01

Summary Alzheimer’s disease (AD) trials initiated during or before the prodrome are costly and lengthy because patients are enrolled long before clinical symptoms are apparent, when disease progression is slow. We hypothesized that design of such trials could be improved by: (1) selecting individuals at moderate near-term risk of progression to AD dementia (the current clinical standard) and (2) by using short-term surrogate endpoints that predict progression to AD dementia. We used a longitudinal cohort of older, initially non-demented, community-dwelling participants (n=358) to derive selection criteria and surrogate endpoints and tested them in an independent national data set (n=6,243). To identify a “mid-risk” subgroup, we applied conditional tree-based survival models to Clinical Dementia Rating (CDR) scale scores and common neuropsychological tests. In the validation cohort, a time-to-AD dementia trial applying these mid-risk selection criteria to a pool of all non-demented individuals could achieve equivalent power with 47% fewer participants than enrolling at random from that pool. We evaluated surrogate endpoints measureable over two years of follow-up based on cross-validated concordance between predictions from Cox models and observed time to AD dementia. The best performing surrogate, rate of change in CDR sum-of-boxes, did not reduce the trial duration required for equivalent power using estimates from the validation cohort, but alternative surrogates with better ability to predict time to AD dementia should be able to do so. The approach tested here might improve efficiency of prodromal AD trials using other potential measures and could be generalized to other diseases with long prodromal phases. PMID:23629586

PTGER4 gene variant rs76523431 is a candidate risk factor for radiological joint damage in rheumatoid arthritis patients: a genetic study of six cohorts.

PubMed

Rodriguez-Rodriguez, Luis; Ivorra-Cortes, Jose; Carmona, F David; Martín, Javier; Balsa, Alejandro; van Steenbergen, Hanna W; van der Helm-van Mil, Annette H M; González-Álvaro, Isidoro; Fernandez-Gutiérrez, Benjamín

2015-11-05

Prostaglandin E receptor 4 (PTGER4) is implicated in immune regulation and bone metabolism. The aim of this study was to analyze its role in radiological joint damage in rheumatoid arthritis (RA). Six independent cohorts of patients with RA of European or North American descent were included, comprising 1789 patients with 5083 sets of X-rays. The Hospital Clínico San Carlos Rheumatoid Arthritis, Princesa Early Arthritis Register Longitudinal study, and Hospital Universitario de La Paz early arthritis (Spain) cohorts were used as discovery cohorts, and the Leiden Early Arthritis Clinic (The Netherlands), Wichita (United States), and National Databank for Rheumatic Diseases (United States and Canada) cohorts as replication cohorts. First, the PTGER4 rs6896969 single-nucleotide polymorphism (SNP) was genotyped using TaqMan assays and available Illumina Immunochip data and studied in the discovery and replication cohorts. Second, the PTGER4 gene and adjacent regions were analyzed using Immunochip genotyping data in the discovery cohorts. On the basis of pooled p values, linkage disequilibrium structure of the region, and location in regions with transcriptional properties, SNPs were selected for replication. The results from discovery, replication, and overall cohorts were pooled using inverse-variance-weighted meta-analysis. Influence of the polymorphisms on the overall radiological damage (constant effect) and on damage progression over time (time-varying effect) was analyzed. The rs6896969 polymorphism showed a significant association with radiological damage in the constant effect pooled analysis of the discovery cohorts, although no significant association was observed in the replication cohorts or the overall pooled analysis. Regarding the analysis of the PTGER4 region, 976 variants were analyzed in the discovery cohorts. From the constant and time-varying effect analyses, 12 and 20 SNPs, respectively, were selected for replication. Only the rs76523431 variant

Simplified methods of determining treatment retention in Malawi: ART cohort reports vs. pharmacy stock cards.

PubMed

Chan, A K; Singogo, E; Changamire, R; Ratsma, Y E C; Tassie, J-M; Harries, A D

2012-06-21

Rapid scale-up of antiretroviral therapy (ART) has challenged the health system in Malawi to monitor large numbers of patients effectively. To compare two methods of determining retention on treatment: quarterly ART clinic data aggregation vs. pharmacy stock cards. Between October 2010 and March 2011, data on ART outcomes were extracted from monitoring tools at five facilities. Pharmacy data on ART consumption were extracted. Workload for each method was observed and timed. We used intraclass correlation and Bland-Altman plots to compare the agreeability of both methods to determine treatment retention. There is wide variability between ART clinic cohort data and pharmacy data to determine treatment retention due to divergence in data at sites with large numbers of patients. However, there is a non-significant trend towards agreeability between the two methods (intraclass correlation coefficient > 0.9; P > 0.05). Pharmacy stock card monitoring is more time-efficient than quarterly ART data aggregation (81 min vs. 573 min). In low-resource settings, pharmacy records could be used to improve drug forecasting and estimate ART retention in a more time-efficient manner than quarterly data aggregation; however, a necessary precondition would be capacity building around pharmacy data management, particularly for large-sized cohorts.

A powerful and efficient set test for genetic markers that handles confounders

PubMed Central

Listgarten, Jennifer; Lippert, Christoph; Kang, Eun Yong; Xiang, Jing; Kadie, Carl M.; Heckerman, David

2013-01-01

Motivation: Approaches for testing sets of variants, such as a set of rare or common variants within a gene or pathway, for association with complex traits are important. In particular, set tests allow for aggregation of weak signal within a set, can capture interplay among variants and reduce the burden of multiple hypothesis testing. Until now, these approaches did not address confounding by family relatedness and population structure, a problem that is becoming more important as larger datasets are used to increase power. Results: We introduce a new approach for set tests that handles confounders. Our model is based on the linear mixed model and uses two random effects—one to capture the set association signal and one to capture confounders. We also introduce a computational speedup for two random-effects models that makes this approach feasible even for extremely large cohorts. Using this model with both the likelihood ratio test and score test, we find that the former yields more power while controlling type I error. Application of our approach to richly structured Genetic Analysis Workshop 14 data demonstrates that our method successfully corrects for population structure and family relatedness, whereas application of our method to a 15 000 individual Crohn’s disease case–control cohort demonstrates that it additionally recovers genes not recoverable by univariate analysis. Availability: A Python-based library implementing our approach is available at http://mscompbio.codeplex.com. Contact: jennl@microsoft.com or lippert@microsoft.com or heckerma@microsoft.com Supplementary information: Supplementary data are available at Bioinformatics online. PMID:23599503

Occupational exposures and Parkinson's disease mortality in a prospective Dutch cohort.

PubMed

Brouwer, Maartje; Koeman, Tom; van den Brandt, Piet A; Kromhout, Hans; Schouten, Leo J; Peters, Susan; Huss, Anke; Vermeulen, Roel

2015-06-01

We investigated the association between six occupational exposures (ie, pesticides, solvents, metals, diesel motor emissions (DME), extremely low frequency magnetic fields (ELF-MF) and electric shocks) and Parkinson's disease (PD) mortality in a large population-based prospective cohort study. The Netherlands Cohort Study on diet and cancer enrolled 58,279 men and 62,573 women aged 55-69 years in 1986. Participants were followed up for cause-specific mortality over 17.3 years, until December 2003, resulting in 402 male and 207 female PD deaths. Following a case-cohort design, a subcohort of 5,000 participants was randomly sampled from the complete cohort. Information on occupational history and potential confounders was collected at baseline. Job-exposure matrices were applied to assign occupational exposures. Associations with PD mortality were evaluated using Cox regression. Among men, elevated HRs were observed for exposure to pesticides (eg, ever high exposed, HR 1.27, 95% CI 0.86 to 1.88) and ever high exposed to ELF-MF (HR 1.54, 95% CI 1.00 to 2.36). No association with exposure duration or trend in cumulative exposure was observed for any of the occupational exposures. Results among women were unstable due to small numbers of high-exposed women. Associations with PD mortality were observed for occupational exposure to pesticides and ELF-MF. However, the weight given to these findings is limited by the absence of a monotonic trend with either duration or cumulative exposure. No associations were found between PD mortality and occupational exposure to solvents, metals, DME or electric shocks. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Cohort profile: The Canadian HIV Women's Sexual and Reproductive Health Cohort Study (CHIWOS).

PubMed

Loutfy, Mona; de Pokomandy, Alexandra; Kennedy, V Logan; Carter, Allison; O'Brien, Nadia; Proulx-Boucher, Karène; Ding, Erin; Lewis, Johanna; Nicholson, Valerie; Beaver, Kerrigan; Greene, Saara; Tharao, Wangari; Benoit, Anita; Dubuc, Danièle; Thomas-Pavanel, Jamie; Sereda, Paul; Jabbari, Shahab; Shurgold, Jayson H; Colley, Guillaume; Hogg, Robert S; Kaida, Angela

2017-01-01

Globally, women are at increased vulnerability to HIV due to biological, social, structural, and political reasons. Women living with HIV also experience unique issues related to their medical and social healthcare, which makes a clinical care model specific to their needs worthy of exploration. Furthermore, there is a dearth of research specific to women living with HIV. Research for this population has often been narrowly focused on pregnancy-related issues without considering their complex structural inequalities, social roles, and healthcare and biological needs. For these reasons, we have come together, as researchers, clinicians and community members in Canada, to develop the Canadian HIV Women's Sexual and Reproductive Health Cohort Study (CHIWOS) to investigate the concept of women-centred HIV care (WCHC) and its impact on the overall, HIV, women's, mental, sexual, and reproductive health outcomes of women living with HIV. Here, we present the CHIWOS cohort profile, which describes the cohort and presents preliminary findings related to perceived WCHC. CHIWOS is a prospective, observational cohort study of women living with HIV in British Columbia (BC), Ontario, and Quebec. Two additional Canadian provinces, Saskatchewan and Manitoba, will join the cohort in 2018. Using community-based research principles, CHIWOS engages women living with HIV throughout the entire research process meeting the requirements of the 'Greater Involvement of People living with HIV/AIDS'. Study data are collected through an interviewer-administered questionnaire that uses a web-based platform. From August 2013 to May 2015, a total of 1422 women living with HIV in BC, Ontario, and Quebec were enrolled and completed the baseline visit. Follow-up interviews are being conducted at 18-month intervals. Of the 1422 participants at baseline, 356 were from BC (25%), 713 from Ontario (50%), 353 from Quebec (25%). The median age of the participants at baseline was 43 years (range, 16-74). 22

Can HIV reverse transcriptase activity assay be a low-cost alternative for viral load monitoring in resource-limited settings?

PubMed

Gupta, Soham; Palchaudhuri, Riya; Neogi, Ujjwal; Srinivasa, Hiresave; Ashorn, Per; De Costa, Ayesha; Källander, Clas; Shet, Anita

2016-01-27

To evaluate the performance and cost of an HIV reverse transcriptase-enzyme activity (HIV-RT) assay in comparison to an HIV-1 RNA assay for routine viral load monitoring in resource limited settings. A cohort-based longitudinal study. Two antiretroviral therapy (ART) centres in Karnataka state, South India, providing treatment under the Indian AIDS control programme. A cohort of 327 HIV-1-infected Indian adult patients initiating first-line ART. Performance and cost of an HIV-RT assay (ExaVir Load V3) in comparison to a gold standard HIV-1 RNA assay (Abbott m2000rt) in a cohort of 327 Indian patients before (WK00) and 4 weeks (WK04) after initiation of first-line therapy. Plasma viral load was determined by an HIV-1 RNA assay and an HIV-RT assay in 629 samples (302 paired samples and 25 single time point samples at WK00) obtained from 327 patients. Overall, a strong correlation of r=0.96 was observed, with good correlation at WK00 (r=0.84) and at WK04 (r=0.77). Bland-Altman analysis of all samples showed a good level of agreement with a mean difference (bias) of 0.22 log10copies/mL. The performance of ExaVir Load V3 was not negatively affected by a nevirapine/efavirenz based antiretroviral regimen. The per test cost of measuring plasma viral load by the Abbott m2000rt and ExaVir Load V3 assays in a basic lab setting was $36.4 and $16.8, respectively. The strong correlation between the HIV-RT and HIV-1 RNA assays suggests that the HIV-RT assay can be an affordable alternative option for monitoring patients on antiretroviral therapy in resource-limited settings. ISRCTN79261738. 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/

Birth-cohort patterns in Crohn's disease and ulcerative colitis.

PubMed

Sonnenberg, Amnon

2014-01-01

To test the long-term time trends of mortality from inflammatory bowel disease (IBD), including Crohn's disease (CD) and ulcerative colitis (UC), for the presence of birth-cohort phenomena. We analyzed mortality data from the national statistical offices of Canada, England and Wales, Italy, the Netherlands, Switzerland, and the USA for the past 60-80 years. Age-specific rates of death were plotted against the period of death, as period-age contours, and against the period of birth, as cohort-age contours. In all six countries alike, the general time trends of IBD have been shaped by an underlying birth-cohort pattern. This pattern was also observed in the data of CD and UC analyzed separately. UC mortality increased in all generations born during the 19th century. It peaked among generations born shortly before the turn of the century and then decreased in all subsequent generations born throughout the 20th century. Compared with UC, the birth-cohort pattern of CD was delayed by 30-50 years. In addition to one risk factor responsible for the general occurrence of IBD and possibly UC alone, there exists at least one additional risk factor responsible for CD. Exposure to both separate risk factors must occur during early life.

Apparent and internal validity of a Monte Carlo-Markov model for cardiovascular disease in a cohort follow-up study.

PubMed

Nijhuis, Rogier L; Stijnen, Theo; Peeters, Anna; Witteman, Jacqueline C M; Hofman, Albert; Hunink, M G Myriam

2006-01-01

To determine the apparent and internal validity of the Rotterdam Ischemic heart disease & Stroke Computer (RISC) model, a Monte Carlo-Markov model, designed to evaluate the impact of cardiovascular disease (CVD) risk factors and their modification on life expectancy (LE) and cardiovascular disease-free LE (DFLE) in a general population (hereinafter, these will be referred to together as (DF)LE). The model is based on data from the Rotterdam Study, a cohort follow-up study of 6871 subjects aged 55 years and older who visited the research center for risk factor assessment at baseline (1990-1993) and completed a follow-up visit 7 years later (original cohort). The transition probabilities and risk factor trends used in the RISC model were based on data from 3501 subjects (the study cohort). To validate the RISC model, the number of simulated CVD events during 7 years' follow-up were compared with the observed number of events in the study cohort and the original cohort, respectively, and simulated (DF)LEs were compared with the (DF)LEs calculated from multistate life tables. Both in the study cohort and in the original cohort, the simulated distribution of CVD events was consistent with the observed number of events (CVD deaths: 7.1% v. 6.6% and 7.4% v. 7.6%, respectively; non-CVD deaths: 11.2% v. 11.5% and 12.9% v. 13.0%, respectively). The distribution of (DF)LEs estimated with the RISC model consistently encompassed the (DF)LEs calculated with multistate life tables. The simulated events and (DF)LE estimates from the RISC model are consistent with observed data from a cohort follow-up study.

Challenges and strategies for cohort retention and data collection in an indigenous population: Australian Aboriginal Birth Cohort.

PubMed

Lawrance, Megan; Sayers, Susan M; Singh, Gurmeet R

2014-02-26

Longitudinal prospective birth cohort studies are pivotal to identifying fundamental causes and determinants of disease and health over the life course. There is limited information about the challenges, retention, and collection strategies in the study of Indigenous populations. The aim is to describe the follow-up rates of an Australian Aboriginal Birth Cohort study and how they were achieved. Participants were 686 babies enrolled between January 1987 and March 1990, born to a mother recorded in the Delivery Suite Register of the Royal Darwin Hospital (RDH) as a self-identified Aboriginal. The majority of the participants (70%) resided in Northern Territory within rural, remote and very remote Aboriginal communities that maintain traditional connections to their land and culture. The Aboriginal communities are within a sparsely populated (0.2 people/ km2) area of approximately 900,000 km² (347 sq miles), with poor communication and transport infrastructures. Follow-ups collecting biomedical and lifestyle data directly from participants in over 40 locations were conducted at 11.4 years (Wave-2) and 18.2 years (Wave-3), with Wave-4 follow-up currently underway. Follow-ups at 11 and 18 years of age successfully examined 86% and 72% of living participants respectively. Strategies addressing logistic, cultural and ethical challenges are documented. Satisfactory follow-up rates of a prospective longitudinal Indigenous birth cohort with traditional characteristics are possible while maintaining scientific rigor in a challenging setting. Approaches included flexibility, respect, and transparent communication along with the adoption of culturally sensitive behaviours. This work should inform and assist researchers undertaking or planning similar studies in Indigenous and developing populations.

Doing No Harm? Adverse Events in a Nation-Wide Cohort of Patients with Multidrug-Resistant Tuberculosis in Nigeria

PubMed Central

Avong, Yohanna Kamabi; Isaakidis, Petros; Hinderaker, Sven Gudmund; Van den Bergh, Rafael; Ali, Engy; Obembe, Bolajoko Oladunni; Ekong, Ernest; Adebamowo, Clement; Ndembi, Nicaise; Okuma, James; Osakwe, Adeline; Oladimeji, Olanrewaju; Akang, Gabriel; Obasanya, Joshua Olusegun; Eltayeb, Osman; Agbaje, Aderonke Vivian; Abimiku, Alash’le; Mensah, Charles Olalekan; Dakum, Patrick Sunday

2015-01-01

Background Adverse events (AEs) of second line anti-tuberculosis drugs (SLDs) are relatively well documented. However, the actual burden has rarely been described in detail in programmatic settings. We investigated the occurrence of these events in the national cohort of multidrug-resistant tuberculosis (MDR-TB) patients in Nigeria. Method This was a retrospective, observational cohort study, using pharmacovigilance data systematically collected at all MDR-TB treatment centers in Nigeria. Characteristics of AEs during the intensive phase treatment were documented, and risk factors for development of AEs were assessed. Results Four hundred and sixty patients were included in the analysis: 62% were male; median age was 33 years [Interquartile Range (IQR):28–42] and median weight was 51 kg (IQR: 45–59). Two hundred and three (44%) patients experienced AEs; four died of conditions associated with SLD AEs. Gastro-intestinal (n = 100), neurological (n = 75), ototoxic (n = 72) and psychiatric (n = 60) AEs were the most commonly reported, whereas ototoxic and psychiatric AEs were the most debilitating. Majority of AEs developed after 1–2 months of therapy, and resolved in less than a month after treatment. Some treatment centers were twice as likely to report AEs compared with others, highlighting significant inconsistencies in reporting at different treatment centers. Patients with a higher body weight had an increased risk of experiencing AEs. No differences were observed in risk of AEs between HIV-infected and uninfected patients. Similarly, age was not significantly associated with AEs. Conclusion Patients in the Nigerian MDR-TB cohort experienced a wide range of AEs, some of which were disabling and fatal. Early identification and prompt management as well as standardized reporting of AEs at all levels of healthcare, including the community is urgently needed. Safer regimens for drug-resistant TB with the shortest duration are advocated. PMID:25781958

Influence function based variance estimation and missing data issues in case-cohort studies.

PubMed

Mark, S D; Katki, H

2001-12-01

Recognizing that the efficiency in relative risk estimation for the Cox proportional hazards model is largely constrained by the total number of cases, Prentice (1986) proposed the case-cohort design in which covariates are measured on all cases and on a random sample of the cohort. Subsequent to Prentice, other methods of estimation and sampling have been proposed for these designs. We formalize an approach to variance estimation suggested by Barlow (1994), and derive a robust variance estimator based on the influence function. We consider the applicability of the variance estimator to all the proposed case-cohort estimators, and derive the influence function when known sampling probabilities in the estimators are replaced by observed sampling fractions. We discuss the modifications required when cases are missing covariate information. The missingness may occur by chance, and be completely at random; or may occur as part of the sampling design, and depend upon other observed covariates. We provide an adaptation of S-plus code that allows estimating influence function variances in the presence of such missing covariates. Using examples from our current case-cohort studies on esophageal and gastric cancer, we illustrate how our results our useful in solving design and analytic issues that arise in practice.

Increasing Use of Nonmedical Analgesics Among Younger Cohorts in the United States: A Birth Cohort Effect

PubMed Central

Miech, Richard; Bohnert, Amy; Heard, Kennon; Boardman, Jason

2017-01-01

Purpose Nonmedical use of prescription pain drugs (hereafter ‘analgesics’) has increased substantially in recent years. It is not known whether today’s youth are disproportionately driving this increase or, instead, the trend is a general one that has affected cohorts of all ages similarly. To address this question we present the first age-period-cohort analysis of nonmedical use of analgesics. Methods Data come from the National Survey on Drug Use and Health, a series of annual, nationally-representative, cross-sectional surveys of the U.S. civilian, non-institutionalized population. The analysis focuses on the years 1985 to 2009 and uses the recently developed ‘intrinsic estimator’ algorithm to disentangle age-period-cohort effects. Results Substantial increases in the prevalence of nonmedical analgesics use have occurred across all cohorts and ages in recent years, but this increase is significantly amplified among today’s adolescents. The odds of past-year, nonmedical analgesics use for today’s youngest cohort (born 1980–1994) are higher than would be expected on the basis of their age and broad, historical period influences that have increased use across people of all ages and cohorts. The independent influence of cohort on past-year, nonmedical analgesics use is about 40% higher for today’s youth cohort than any of the cohorts that came before them. This finding is present among men, women, non-Hispanic whites, non-Hispanic blacks, and Hispanics. Conclusions Although nonmedical use of analgesics is evident among all ages, cohorts, and periods, today’s younger cohorts warrant special attention for substance abuse policies and interventions targeted at reversing the increase in nonmedical analgesics use. PMID:23260832

Integrating palliative care across settings: A retrospective cohort study of a hospice home care programme for cancer patients.

PubMed

Tan, Woan Shin; Lee, Angel; Yang, Sze Yee; Chan, Susan; Wu, Huei Yaw; Ng, Charis Wei Ling; Heng, Bee Hoon

2016-07-01

Terminally ill patients at the end-of-life do transit between care settings due to their complex care needs. Problems of care fragmentation could result in poor quality of care. We aimed to evaluate the impact of an integrated hospice home care programme on acute care service usage and on the share of home deaths. The retrospective study cohort comprised patients who were diagnosed with cancer, had an expected prognosis of 1 year or less, and were referred to a home hospice. The intervention group comprised deceased patients enrolled in the integrated hospice home care programme between September 2012 and June 2014. The historical comparison group comprised deceased patients who were referred to other home hospices between January 2007 and January 2011. There were 321 cases and 593 comparator subjects. Relative to the comparator group, the share of hospital deaths was significantly lower for programme participants (12.1% versus 42.7%). After adjusting for differences at baseline, the intervention group had statistically significantly lower emergency department visits at 30 days (incidence rate ratio: 0.38; 95% confidence interval: 0.31-0.47), 60 days (incidence rate ratio: 0.61; 95% confidence interval: 0.54-0.69) and 90 days (incidence rate ratio: 0.69; 95% confidence interval: 0.62-0.77) prior to death. Similar results held for the number of hospitalisations at 30 days (incidence rate ratio: 0.48; 95% confidence interval: 0.40-0.58), 60 days (incidence rate ratio: 0.71; 95% confidence interval: 0.62-0.82) and 90 days (incidence rate ratio: 0.77; 95% confidence interval: 0.68-0.88) prior to death. Our results demonstrated that by integrating services between acute care and home hospice care, a reduction in acute care service usage could occur. © The Author(s) 2016.

Vaccine coverage and adherence to EPI schedules in eight resource poor settings in the MAL-ED cohort study.

PubMed

Hoest, Christel; Seidman, Jessica C; Lee, Gwenyth; Platts-Mills, James A; Ali, Asad; Olortegui, Maribel Paredes; Bessong, Pascal; Chandyo, Ram; Babji, Sudhir; Mohan, Venkata Raghava; Mondal, Dinesh; Mahfuz, Mustafa; Mduma, Estomih R; Nyathi, Emanuel; Abreu, Claudia; Miller, Mark A; Pan, William; Mason, Carl J; Knobler, Stacey L

2017-01-11

Launched in 1974, the Expanded Program on Immunization (EPI) is estimated to prevent two-three million deaths annually from polio, diphtheria, tuberculosis, pertussis, measles, and tetanus. Additional lives could be saved through better understanding what influences adherence to the EPI schedule in specific settings. The Etiology, Risk Factors and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development (MAL-ED) study followed cohorts in eight sites in South Asia, Africa, and South America and monitored vaccine receipt over the first two years of life for the children enrolled in the study. Vaccination histories were obtained monthly from vaccination cards, local clinic records and/or caregiver reports. Vaccination histories were compared against the prescribed EPI schedules for each country, and coverage rates were examined in relation to the timing of vaccination. The influence of socioeconomic factors on vaccine timing and coverage was also considered. Coverage rates for EPI vaccines varied between sites and by type of vaccine; overall, coverage was highest in the Nepal and Bangladesh sites and lowest in the Tanzania and Brazil sites. Bacillus Calmette-Guérin coverage was high across all sites, 87-100%, whereas measles vaccination rates ranged widely, 73-100%. Significant delays between the scheduled administration age and actual vaccination date were present in all sites, especially for measles vaccine where less than 40% were administered on schedule. A range of socioeconomic factors were significantly associated with vaccination status in study children but these results were largely site-specific. Our findings highlight the need to improve measles vaccination rates and reduce delayed vaccination to achieve EPI targets related to the establishment of herd immunity and reduction in disease transmission. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Use of a 17-Gene Prognostic Assay in Contemporary Urologic Practice: Results of an Interim Analysis in an Observational Cohort.

PubMed

Eure, Gregg; Germany, Raymond; Given, Robert; Lu, Ruixiao; Shindel, Alan W; Rothney, Megan; Glowacki, Richard; Henderson, Jonathan; Richardson, Tim; Goldfischer, Evan; Febbo, Phillip G; Denes, Bela S

2017-09-01

To study the impact of genomic testing in shared decision making for men with clinically low-risk prostate cancer (PCa). Patients with clinically low-risk PCa were enrolled in a prospective, multi-institutional study of a validated 17-gene tissue-based reverse transcription polymerase chain reaction assay (Genomic Prostate Score [GPS]). In this paper we report on outcomes in the first 297 patients enrolled in the study with valid 17-gene assay results and decision-change data. The primary end points were shared decision on initial management and persistence on active surveillance (AS) at 1 year post diagnosis. AS utilization and persistence were compared with similar end points in a group of patients who did not have genomic testing (baseline cohort). Secondary end points included perceived utility of the assay and patient decisional conflict before and after testing. One-year results were available on 258 patients. Shift between initial recommendation and shared decision occurred in 23% of patients. Utilization of AS was higher in the GPS-tested cohort than in the untested baseline cohort (62% vs 40%). The proportion of men who selected and persisted on AS at 1 year was 55% and 34% in the GPS and baseline cohorts, respectively. Physicians reported that GPS was useful in 90% of cases. Mean decisional conflict scores declined in patients after GPS testing. Patients who received GPS testing were more likely to select and persist on AS for initial management compared with a matched baseline group. These data indicate that GPS help guide shared decisions in clinically low-risk PCa. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Set-up uncertainties: online correction with X-ray volume imaging.

PubMed

Kataria, Tejinder; Abhishek, Ashu; Chadha, Pranav; Nandigam, Janardhan

2011-01-01

To determine interfractional three-dimensional set-up errors using X-ray volumetric imaging (XVI). Between December 2007 and August 2009, 125 patients were taken up for image-guided radiotherapy using online XVI. After matching of reference and acquired volume view images, set-up errors in three translation directions were recorded and corrected online before treatment each day. Mean displacements, population systematic (Σ), and random (σ) errors were calculated and analyzed using SPSS (v16) software. Optimum clinical target volume (CTV) to planning target volume (PTV) margin was calculated using Van Herk's (2.5Σ + 0.7 σ) and Stroom's (2Σ + 0.7 σ) formula. Patients were grouped in 4 cohorts, namely brain, head and neck, thorax, and abdomen-pelvis. The mean vector displacement recorded were 0.18 cm, 0.15 cm, 0.36 cm, and 0.35 cm for brain, head and neck, thorax, and abdomen-pelvis, respectively. Analysis of individual mean set-up errors revealed good agreement with the proposed 0.3 cm isotropic margins for brain and 0.5 cm isotropic margins for head-neck. Similarly, 0.5 cm circumferential and 1 cm craniocaudal proposed margins were in agreement with thorax and abdomen-pelvic cases. The calculated mean displacements were well within CTV-PTV margin estimates of Van Herk (90% population coverage to minimum 95% prescribed dose) and Stroom (99% target volume coverage by 95% prescribed dose). Employing these individualized margins in a particular cohort ensure comparable target coverage as described in literature, which is further improved if XVI-aided set-up error detection and correction is used before treatment.

Polysomnographic Findings and Clinical Correlates in Huntington Disease: A Cross-Sectional Cohort Study

PubMed Central

Piano, Carla; Losurdo, Anna; Della Marca, Giacomo; Solito, Marcella; Calandra-Buonaura, Giovanna; Provini, Federica; Bentivoglio, Anna Rita; Cortelli, Pietro

2015-01-01

Study Objectives: To evaluate the sleep pattern and the motor activity during sleep in a cohort of patients affected by Huntington disease (HD). Design: Cross-sectional cohort study. Setting: Sleep laboratory. Patients: Thirty HD patients, 16 women and 14 men (mean age 57.3 ± 12.2 y); 30 matched healthy controls (mean age 56.5 ± 11.8 y). Interventions: Subjective sleep evaluation: Epworth Sleepiness Scale (ESS); Berlin's Questionnaire, interview for restless legs syndrome (RLS), questionnaire for REM sleep behavior disorder (RBD). Clinical evaluation: disease duration, clinical severity (unified Huntington disease motor rating scale [UHDMRS]), genetic tests. Laboratory-based full-night attended video-polysomnography (V-PSG). Measurements and Results: The duration of the disease was 9.4 ± 4.4 y, UHMDRS score was 55.5 ± 23.4, CAG repeats were 44.3 ± 4.1. Body mass index was 21.9 ± 4.0 kg/m2. No patients or caregivers reported poor sleep quality. Two patients reported symptoms of RLS. Eight patients had an ESS score ≥ 9. Eight patients had high risk of obstructive sleep apnea. At the RBD questionnaire, two patients had a pathological score. HD patients, compared to controls, showed shorter sleep, reduced sleep efficiency index, and increased arousals and awakenings. Four patients presented with sleep disordered breathing (SDB). Periodic limb movements (PLMs) during wake and sleep were observed in all patients. No episode of RBD was observed in the V-PSG recordings, and no patients showed rapid eye movement (REM) sleep without atonia. The disease duration correlated with ESS score (P < 0.02). UHMDRS correlated positively with the ESS score (P < 0.005), and negatively with the percentage of REM sleep. Conclusions: Patients with Huntington disease showed a severe sleep disruption and a high prevalence of periodic limb movements, but no evidence of sleep disordered breathing or REM sleep behavior disorder. Citation: Piano C, Losurdo A, Della Marca G, Solito M

The apparent breastfeeding paradox in very preterm infants: relationship between breast feeding, early weight gain and neurodevelopment based on results from two cohorts, EPIPAGE and LIFT

PubMed Central

Darmaun, Dominique; Boquien, Clair-Yves; Flamant, Cyril; Picaud, Jean-Charles; Savagner, Christophe; Claris, Olivier; Lapillonne, Alexandre; Mitanchez, Delphine; Branger, Bernard; Simeoni, Umberto; Kaminski, Monique; Ancel, Pierre-Yves

2012-01-01

Context Supplementation of breast milk is difficult once infants suckle the breast and is often discontinued at end of hospitalisation and after discharge. Thus, breastfed preterm infants are exposed to an increased risk of nutritional deficit with a possible consequence on neurodevelopmental outcome. Objective To assess the relationship between breast feeding at time of discharge, weight gain during hospitalisation and neurodevelopmental outcome. Design Observational cohort study. Setting Two large, independent population-based cohorts of very preterm infants: the Loire Infant Follow-up Team (LIFT) and the EPIPAGE cohorts. Patients 2925 very preterm infants alive at discharge. Main outcome measure Suboptimal neurodevelopmental outcome, defined as a score in the lower tercile, using Age and Stages Questionnaire at 2 years in LIFT and Kaufman Assessment Battery for Children Test at 5 years in EPIPAGE. Two propensity scores for breast feeding at discharge, one for each cohort, were used to reduce bias. Results Breast feeding at time of discharge concerned only 278/1733 (16%) infants in LIFT and 409/2163 (19%) infants in EPIPAGE cohort. Breast feeding is significantly associated with an increased risk of losing one weight Z-score during hospitalisation (LIFT: n=1463, adjusted odd ratio (aOR)=2.51 (95% CI 1.87 to 3.36); EPIPAGE: n=1417, aOR=1.55 (95% CI 1.14 to 2.12)) and with a decreased risk for a suboptimal neurodevelopmental assessment (LIFT: n=1463, aOR=0.63 (95% CI 0.45 to 0.87); EPIPAGE: n=1441, aOR=0.65 (95% CI 0.47 to 0.89) and an increased chance of having a head circumference Z-score higher than 0.5 at 2 years in LIFT cohort (n=1276, aOR=1.43 (95% CI 1.02 to 2.02)) and at 5 years in EPIPAGE cohort (n=1412, aOR=1.47 (95% CI 1.10 to 1.95)). Conclusions The observed better neurodevelopment in spite of suboptimal initial weight gain could be termed the ‘apparent breastfeeding paradox’ in very preterm infants. Regardless of the mechanisms involved

NCI Cohort Consortium Membership

Cancer.gov

The NCI Cohort Consortium membership is international and includes investigators responsible for more than 40 high-quality cohorts who are studying large and diverse populations in more than 15 different countries.

Creating a Common Data Model for Comparative Effectiveness with the Observational Medical Outcomes Partnership.

PubMed

FitzHenry, F; Resnic, F S; Robbins, S L; Denton, J; Nookala, L; Meeker, D; Ohno-Machado, L; Matheny, M E

2015-01-01

Adoption of a common data model across health systems is a key infrastructure requirement to allow large scale distributed comparative effectiveness analyses. There are a growing number of common data models (CDM), such as Mini-Sentinel, and the Observational Medical Outcomes Partnership (OMOP) CDMs. In this case study, we describe the challenges and opportunities of a study specific use of the OMOP CDM by two health systems and describe three comparative effectiveness use cases developed from the CDM. The project transformed two health system databases (using crosswalks provided) into the OMOP CDM. Cohorts were developed from the transformed CDMs for three comparative effectiveness use case examples. Administrative/billing, demographic, order history, medication, and laboratory were included in the CDM transformation and cohort development rules. Record counts per person month are presented for the eligible cohorts, highlighting differences between the civilian and federal datasets, e.g. the federal data set had more outpatient visits per person month (6.44 vs. 2.05 per person month). The count of medications per person month reflected the fact that one system's medications were extracted from orders while the other system had pharmacy fills and medication administration records. The federal system also had a higher prevalence of the conditions in all three use cases. Both systems required manual coding of some types of data to convert to the CDM. The data transformation to the CDM was time consuming and resources required were substantial, beyond requirements for collecting native source data. The need to manually code subsets of data limited the conversion. However, once the native data was converted to the CDM, both systems were then able to use the same queries to identify cohorts. Thus, the CDM minimized the effort to develop cohorts and analyze the results across the sites.

The rapid suicide protection of mood stabilizers on patients with bipolar disorder: A nationwide observational cohort study in Taiwan.

PubMed

Tsai, Chia-Jui; Cheng, Chin; Chou, Po-Han; Lin, Ching-Heng; McInnis, Melvin G; Chang, Chia-Li; Lan, Tsuo-Hung

2016-05-15

The suicide rate is high among bipolar disorder (BD) patients. Previous studies have focused on the anti-suicidal effect of long-term treatment with mood stabilizers but less on the immediate preventive effects of interventions. The aim of the study was to evaluate the short-term and immediate anti-suicidal effects of mood stabilizers on recent-onset BD patients. The National Health Insurance Database (NHID) of Taiwan was used to perform a nationwide cohort observation study of suicide behaviors in bipolar disorder. All the recent-onset BD patients (ICD-9-CM code 296 except 296.2 and 296.3) diagnosed between 2000-2005 were collected (n=5091) and followed through 2009. The primary endpoint was the presence of a suicide code or the end of observation; exposure to mood stabilizers in the final month of observation was the independent variable. The hazard ratios (HRs) of suicide-related events, completed suicide, and all-cause mortality were significantly lower for those treated with lithium, divalproex, or carbamazepine compared with no use in the last month (HRs of suicide-related events were 0.10, 0.14 and 0.10, respectively, and all-cause mortality HRs were 0.03; P<0.0001); there was no significant difference in HR between the mood stabilizers. The NIHD does not provide information on the severity, mood status, or treatment adherence of BD patients. Neither substance-related disorder nor personality disorder were included in the analysis. We focused on the effect of the final prescription time period, not the long-term protective effect. The immediate recent use of any mood stabilizer significantly lowers the rate of death, suicide, or suicidal behavior in BD. Copyright © 2016 Elsevier B.V. All rights reserved.

Education and fertility decline in China during transitional times: A cohort approach.

PubMed

Piotrowski, Martin; Tong, Yuying

2016-01-01

We examine the effect of education on birth outcomes in China during the period of economic transition and large-scale changes in mass education and population control measures. Retrospective micro data from the 2008 Chinese General Social Survey and discrete time event history analysis are used to examine the fertility history of several cohorts of women born between 1945 and 1968. We observed births at different parities, distinguishing the education effect across cohorts and rural/urban sectors. We found differences across cohorts consistent with unique features of the Chinese context, such as the radical egalitarian era of educational expansion, and the Reform Era. We also found that despite the increase in some education levels across cohorts (e.g., junior high school in rural areas), birth chances were more likely to be concentrated among less educated women, suggesting the impact of factors related to returns to education and hence the desire for children. Copyright © 2015 Elsevier Inc. All rights reserved.

Designing Reliable Cohorts of Cardiac Patients across MIMIC and eICU

PubMed Central

Chronaki, Catherine; Shahin, Abdullah; Mark, Roger

2016-01-01

The design of the patient cohort is an essential and fundamental part of any clinical patient study. Knowledge of the Electronic Health Records, underlying Database Management System, and the relevant clinical workflows are central to an effective cohort design. However, with technical, semantic, and organizational interoperability limitations, the database queries associated with a patient cohort may need to be reconfigured in every participating site. i2b2 and SHRINE advance the notion of patient cohorts as first class objects to be shared, aggregated, and recruited for research purposes across clinical sites. This paper reports on initial efforts to assess the integration of Medical Information Mart for Intensive Care (MIMIC) and Philips eICU, two large-scale anonymized intensive care unit (ICU) databases, using standard terminologies, i.e. LOINC, ICD9-CM and SNOMED-CT. Focus of this work is lab and microbiology observations and key demographics for patients with a primary cardiovascular ICD9-CM diagnosis. Results and discussion reflecting on reference core terminology standards, offer insights on efforts to combine detailed intensive care data from multiple ICUs worldwide. PMID:27774488

Nordic registry-based cohort studies: Possibilities and pitfalls when combining Nordic registry data.

PubMed

Maret-Ouda, John; Tao, Wenjing; Wahlin, Karl; Lagergren, Jesper

2017-07-01

All five Nordic countries (Denmark, Finland, Iceland, Norway and Sweden) have nationwide registries with similar data structure and validity, as well as personal identity numbers enabling linkage between registries. These resources provide opportunities for medical research that is based on large registry-based cohort studies with long and complete follow-up. This review describes practical aspects, opportunities and challenges encountered when setting up all-Nordic registry-based cohort studies. Relevant articles describing registries often used for medical research in the Nordic countries were retrieved. Further, our experiences of conducting this type of study, including planning, acquiring permissions, data retrieval and data cleaning and handling, and the possibilities and challenges we have encountered are described. Combining data from the Nordic countries makes it possible to create large and powerful cohorts. The main challenges include obtaining all permissions within each country, usually in the local language, and retrieving the data. These challenges emphasise the importance of having experienced collaborators within each country. Following the acquisition of data, data management requires the understanding of the differences between the variables to be used in the various countries. A concern is the long time required between initiation and completion. Nationwide Nordic registries can be combined into cohorts with high validity and statistical power, but the considerable expertise, workload and time required to complete such cohorts should not be underestimated.

The Minimum Data Set 3.0 Cognitive Function Scale.

PubMed

Thomas, Kali S; Dosa, David; Wysocki, Andrea; Mor, Vincent

2017-09-01

The Minimum Data Set (MDS) 3.0 introduced the Brief Interview for Mental Status (BIMS), a short performance-based cognitive screener for nursing home (NH) residents. Not all residents are able to complete the BIMS and are consequently assessed by staff. We designed a Cognitive Function Scale (CFS) integrating self-report and staff-report data and present evidence of the scale's construct validity. A retrospective cohort study. The subjects consisted of 3 cohorts: (1) long-stay NH residents (N=941,077) and (2) new admissions (N=2,066,580) during 2011-2012, and (3) residents with the older MDS 2.0 assessment in 2010 and the newer MDS 3.0 assessment (n=688,511). MDS 3.0 items were used to create a single, integrated 4-category hierarchical CFS that was compared with residents' prior MDS 2.0 Cognitive Performance Scale scores and other concurrent MDS 3.0 measures of construct validity. The new CFS suggests that 28% of the long-stay cohort in 2011-2012 were cognitively intact, 22% were mildly impaired, 33% were moderately impaired, and 17% were severely impaired. For the admission cohort, the CFS noted 56% as cognitively intact, 23% as mildly impaired, 17% as moderately impaired, and 4% as severely impaired. The CFS corresponded closely with residents' prior MDS 2.0 Cognitive Performance Scale scores and with performance of Activities of Daily Living, and nurses' judgments of function and behavior in both the admission and long-stay cohorts. The new CFS is valuable to researchers as it provides a single, integrated measure of NH residents' cognitive function, regardless of the mode of assessment.

Mortality in patients with diabetes mellitus and Addison's disease: a nationwide, matched, observational cohort study.

PubMed

Chantzichristos, Dimitrios; Persson, Anders; Eliasson, Björn; Miftaraj, Mervete; Franzén, Stefan; Bergthorsdottir, Ragnhildur; Gudbjörnsdottir, Soffia; Svensson, Ann-Marie; Johannsson, Gudmundur

2017-01-01

Our hypothesis was that patients with diabetes mellitus obtain an additional risk of death if they develop Addison's disease (AD). Nationwide, matched, observational cohort study cross-referencing the Swedish National Diabetes Register with Inpatient, Cancer and Cause of Death Registers in patients with diabetes (type 1 and 2) and AD and matched controls with diabetes. Clinical characteristics at baseline, overall, and cause-specific mortality were assessed. The relative risk of death was assessed using a Cox proportional hazards regression model. Between January 1996 and December 2012, 226 patients with diabetes and AD were identified and matched with 1129 controls with diabetes. Median (interquartile range) follow-up was 5.9 (2.7-8.6) years. When patients with diabetes were diagnosed with AD, they had an increased frequency of diabetes complications, but both medical history of cancer and coronary heart disease did not differ compared with controls. Sixty-four of the 226 patients with diabetes and AD (28%) died, while 112 of the 1129 controls (10%) died. The estimated relative risk increase (hazard ratio) in overall mortality in the diabetes and AD group was 3.89 (95% confidence interval 2.84-5.32) compared with controls with diabetes. The most common cause of death was cardiovascular in both groups, but patients with diabetes and AD showed an increased death rate from diabetes complications, infectious diseases and unknown causes. Patients with the rare combination of diabetes and AD showed a markedly increased mortality and died more frequently from infections and unknown causes than patients with diabetes alone. Improved strategy for the management of this combination of metabolic disorders is needed. © 2017 European Society of Endocrinology.

Newborn literacy program effective in increasing maternal engagement in literacy activities: an observational cohort study

PubMed Central

2012-01-01

Background Literacy is important for success in school and in adulthood. Book-gift programs at birth exist to help develop these foundations early on. The effectiveness of the Read to Me! Nova Scotia Family Literacy Program (a program where books and literacy materials are given to families in hospital when their baby is born) on the duration and frequency with which mothers engage in reading and other literacy based activities with their newborns was assessed. Methods An observational cohort study design was used. Mothers of babies who received the Read to Me! package in Nova Scotia born between January-August 2006 made up the intervention group (N = 1051). Mothers of babies born in Prince Edward Island between December 2006 and March 2008 made up the control group (N = 279) and did not receive any literacy package when their baby was born. A phone questionnaire was conducted consisting of questions regarding frequency and duration of maternal engagement in language and literacy-based activities with their infants. These activities included reading, singing, talking, listening to CDs and the radio and watching TV. Babies were aged 0–10 months at the time of the interview. Results Mothers who received the Read to Me! literacy package spent significantly more time reading to their babies, 17.9 ± 17.6 min/day compared to controls 12.6 ± 10.7 min/day, (p < 0.0001). Conclusions Read to Me! may be an inexpensive, easy to administer and effective intervention which results in increased shared reading of mothers and their newborns. PMID:22799492

Exposure reconstruction for the TCDD-exposed NIOSH cohort using a concentration- and age-dependent model of elimination.

PubMed

Aylward, Lesa L; Brunet, Robert C; Starr, Thomas B; Carrier, Gaétan; Delzell, Elizabeth; Cheng, Hong; Beall, Colleen

2005-08-01

Recent studies demonstrating a concentration dependence of elimination of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) suggest that previous estimates of exposure for occupationally exposed cohorts may have underestimated actual exposure, resulting in a potential overestimate of the carcinogenic potency of TCDD in humans based on the mortality data for these cohorts. Using a database on U.S. chemical manufacturing workers potentially exposed to TCDD compiled by the National Institute for Occupational Safety and Health (NIOSH), we evaluated the impact of using a concentration- and age-dependent elimination model (CADM) (Aylward et al., 2005) on estimates of serum lipid area under the curve (AUC) for the NIOSH cohort. These data were used previously by Steenland et al. (2001) in combination with a first-order elimination model with an 8.7-year half-life to estimate cumulative serum lipid concentration (equivalent to AUC) for these workers for use in cancer dose-response assessment. Serum lipid TCDD measurements taken in 1988 for a subset of the cohort were combined with the NIOSH job exposure matrix and work histories to estimate dose rates per unit of exposure score. We evaluated the effect of choices in regression model (regression on untransformed vs. ln-transformed data and inclusion of a nonzero regression intercept) as well as the impact of choices of elimination models and parameters on estimated AUCs for the cohort. Central estimates for dose rate parameters derived from the serum-sampled subcohort were applied with the elimination models to time-specific exposure scores for the entire cohort to generate AUC estimates for all cohort members. Use of the CADM resulted in improved model fits to the serum sampling data compared to the first-order models. Dose rates varied by a factor of 50 among different combinations of elimination model, parameter sets, and regression models. Use of a CADM results in increases of up to five-fold in AUC estimates for the more

Disease fatality and bias in survival cohorts.

PubMed

Barry, Vaughn; Klein, Mitchel; Winquist, Andrea; Darrow, Lyndsey A; Steenland, Kyle

2015-07-01

Simulate how the effect of exposure on disease occurrence and fatality influences the presence and magnitude of bias in survivor cohorts, motivated by an actual survivor cohort under study. We simulated a cohort of 50,000 subjects exposed to a disease-causing exposure over time and followed forty years, where disease incidence was the outcome of interest. We simulated this 'inception' cohort under different assumptions about the effect of exposure on disease occurrence and fatality after disease occurrence. We then created a corresponding 'survivor' (or 'cross-sectional') cohort, where cohort enrollment took place at a specific date after exposure began in the inception cohort; subjects dying prior to that enrollment date were excluded. The disease of interest caused all deaths in our simulations, but was not always fatal. In the survivor cohort, person-time at risk began before enrollment for all subjects who did not die prior to enrollment. We compared exposure-disease associations in each inception cohort to those in corresponding survivor cohorts to determine how different assumptions impacted bias in the survivor cohorts. All subjects in both inception and survivor cohorts were considered equally susceptible to the effect of exposure in causing disease. We used Cox proportional hazards regression to calculate effect measures. There was no bias in survivor cohort estimates when case fatality among diseased subjects was independent of exposure. This was true even when the disease was highly fatal and more highly exposed subjects were more likely to develop disease and die. Assuming a positive exposure-response in the inception cohort, survivor cohort rate ratios were biased downwards when case fatality was greater with higher exposure. Survivor cohort effect estimates for fatal outcomes are not always biased, although precision can decrease. Copyright © 2015 Elsevier Inc. All rights reserved.

Gestational age and adolescent mental health: evidence from Hong Kong's 'Children of 1997' birth cohort.

PubMed

Wang, Hui; Leung, Gabriel M; Lam, H S; Schooling, C Mary

2015-09-01

Preterm, and more recently early term, birth has been identified as a risk factor for poor health. Whether the sequelae of late preterm or early term birth extends to poor mental health and well-being in adolescence is unclear and has not been systematically assessed. Linear regression was used to assess the adjusted associations of gestational age (very/moderate preterm (<34 weeks, n=85), late preterm (34-36 weeks, n=305), early term (37-38 weeks, n=2228), full term (39-40 weeks, n=4018), late term (41 weeks, n=809), post-term (≥42 weeks, n=213)) with self-reported self-esteem at ∼11 years (n=6935), parent-reported Rutter score assessing the common emotional and behavioural problems at ∼7 years (n=6292) and ∼11 years (n=5596) and self-reported depressive symptoms at ∼13 years (n=5795) in a population-representative Hong Kong Chinese birth cohort 'Children of 1997' where gestational age has little social patterning. Very/moderate preterm birth was associated with higher Rutter subscore for hyperactivity (ß coefficients 0.5, 95% CI 0.01 to 1.00) at ∼7 years but not at ∼11 years, adjusted for sex, age, socio-economic position, parents' age at birth, birth order and secondhand smoke exposure. Similarly adjusted, late preterm, early term, late term and post-term birth were not associated with self-esteem or depressive symptoms. In a population-representative birth cohort from a non-Western-developed setting, gestational age had few associations with mental health and well-being in adolescence, whereas very preterm birth was specifically associated with hyperactivity in childhood. Inconsistencies with studies from Western settings suggest setting specific unmeasured confounding may underlie any observed associations. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Digital Immigrants: An Exploration of Their Technological Knowledge and Skill Sets

ERIC Educational Resources Information Center

Walker, Benjamin

2012-01-01

This instrumental case study explored the knowledge and skill set levels of adult learners over the age of 35 with an emphasis in emerging educational technologies. The case study focused on EdD students in four cohorts at the Drexel University Center for Graduate Studies in Sacramento, CA. This research sought to answer the following research…

Thromboembolism in inflammatory bowel disease: results from a prospective, population-based European inception cohort.

PubMed

Isene, Rune; Bernklev, Tomm; Høie, Ole; Langholz, Ebbe; Tsianos, Epameonondas; Stockbrügger, Reinhold; Odes, Selwyn; Småstuen, Milada; Moum, Bjørn

2014-07-01

Patients with inflammatory bowel disease (IBD) have proven an increased risk of venous thromboembolism (VTE), particularly when hospitalized. The estimate of the true risk varies considerably between studies, primarily due to differences in methodology. We set out to determine the incidence of VTE in a population-based European inception cohort. IBD patients were incepted into a cohort that was prospectively followed from the early 1990s to the early 2000s. A total of 1145 patients were followed for a total of 10,634 patient-years (p.y.). A total of 19 thromboembolic events were identified - 13 deep vein thrombosis and 6 with pulmonary embolism. The incidence rate of VTE was 1.8 per 1000 p.y. The risk of VTE was elevated in this IBD cohort but lower than previously reported. The highest risk was seen in hospitalized patients, but corticosteroids-requiring disease in outpatients also conferred some risk.

Lung cancer incidence trends in Uruguay 1990-2014: An age-period-cohort analysis.

PubMed

Alonso, Rafael; Piñeros, Marion; Laversanne, Mathieu; Musetti, Carina; Garau, Mariela; Barrios, Enrique; Bray, Freddie

2018-05-11

Uruguay, a country with one of the highest lung cancer rates worldwide, initiated a series of comprehensive anti-smoking measures in 2005. We assess the tobacco control policies in the context of cohort-driven lung cancer incidence trends over a 25-year period, providing baseline predictions to 2035. Using data from the National Cancer Registry of Uruguay, an age-period-cohort analysis of trends 1990-2014 was performed. The NORDPRED package was used to predict the annual number of new cases of lung cancer and incidence rates up to 2035. In men, age-standardised (world) rates declined from a peak of 165.6 in 1995 to 103.1 by 2014, translating to a 70% reduction in the risk of lung cancer in men born in 1970 relative to the early-1940s. In females, rates increased steadily from 18.3 in 1991 to 30.0 by 2014, with successive increases in risk among generations of women born 1940-1960. There is however evidence of a decline in observed rates in women born recently. Extrapolations of the trends indicate an 8% reduction in the mean number of new lung cancer cases in men by 2035, but a 69% increase in women. Despite observed and predicted reductions in lung cancer incidence in Uruguayan men, rates among women are set to continue to increase, with a large rise in the annual number of female lung cancer diagnoses expected before 2035. There are signals of a diminishing risk among recent generations of women born after 1960. The current analysis provides important baseline information in assessing the future impact of the recent tobacco control initiatives in Uruguay. Copyright © 2018 Elsevier Ltd. All rights reserved.

34 CFR 668.204 - Draft cohort default rates and your ability to challenge before official cohort default rates are...

Code of Federal Regulations, 2011 CFR

2011-07-01

... 34 Education 3 2011-07-01 2011-07-01 false Draft cohort default rates and your ability to... OF EDUCATION STUDENT ASSISTANCE GENERAL PROVISIONS Cohort Default Rates § 668.204 Draft cohort.... (1) We notify you of your draft cohort default rate before your official cohort default rate is...

34 CFR 668.204 - Draft cohort default rates and your ability to challenge before official cohort default rates are...

Code of Federal Regulations, 2012 CFR

2012-07-01

... 34 Education 3 2012-07-01 2012-07-01 false Draft cohort default rates and your ability to... OF EDUCATION STUDENT ASSISTANCE GENERAL PROVISIONS Cohort Default Rates § 668.204 Draft cohort.... (1) We notify you of your draft cohort default rate before your official cohort default rate is...

34 CFR 668.204 - Draft cohort default rates and your ability to challenge before official cohort default rates are...

Code of Federal Regulations, 2014 CFR

2014-07-01

... 34 Education 3 2014-07-01 2014-07-01 false Draft cohort default rates and your ability to... OF EDUCATION STUDENT ASSISTANCE GENERAL PROVISIONS Cohort Default Rates § 668.204 Draft cohort.... (1) We notify you of your draft cohort default rate before your official cohort default rate is...

34 CFR 668.204 - Draft cohort default rates and your ability to challenge before official cohort default rates are...

Code of Federal Regulations, 2013 CFR

2013-07-01

... 34 Education 3 2013-07-01 2013-07-01 false Draft cohort default rates and your ability to... OF EDUCATION STUDENT ASSISTANCE GENERAL PROVISIONS Cohort Default Rates § 668.204 Draft cohort.... (1) We notify you of your draft cohort default rate before your official cohort default rate is...

Cohort profile: The Canadian HIV Women’s Sexual and Reproductive Health Cohort Study (CHIWOS)

PubMed Central

de Pokomandy, Alexandra; Kennedy, V. Logan; Carter, Allison; O’Brien, Nadia; Proulx-Boucher, Karène; Ding, Erin; Lewis, Johanna; Nicholson, Valerie; Beaver, Kerrigan; Greene, Saara; Tharao, Wangari; Benoit, Anita; Dubuc, Danièle; Thomas-Pavanel, Jamie; Sereda, Paul; Jabbari, Shahab; Shurgold, Jayson H.; Colley, Guillaume; Hogg, Robert S.; Kaida, Angela

2017-01-01

Globally, women are at increased vulnerability to HIV due to biological, social, structural, and political reasons. Women living with HIV also experience unique issues related to their medical and social healthcare, which makes a clinical care model specific to their needs worthy of exploration. Furthermore, there is a dearth of research specific to women living with HIV. Research for this population has often been narrowly focused on pregnancy-related issues without considering their complex structural inequalities, social roles, and healthcare and biological needs. For these reasons, we have come together, as researchers, clinicians and community members in Canada, to develop the Canadian HIV Women’s Sexual and Reproductive Health Cohort Study (CHIWOS) to investigate the concept of women-centred HIV care (WCHC) and its impact on the overall, HIV, women’s, mental, sexual, and reproductive health outcomes of women living with HIV. Here, we present the CHIWOS cohort profile, which describes the cohort and presents preliminary findings related to perceived WCHC. CHIWOS is a prospective, observational cohort study of women living with HIV in British Columbia (BC), Ontario, and Quebec. Two additional Canadian provinces, Saskatchewan and Manitoba, will join the cohort in 2018. Using community-based research principles, CHIWOS engages women living with HIV throughout the entire research process meeting the requirements of the ‘Greater Involvement of People living with HIV/AIDS’. Study data are collected through an interviewer-administered questionnaire that uses a web-based platform. From August 2013 to May 2015, a total of 1422 women living with HIV in BC, Ontario, and Quebec were enrolled and completed the baseline visit. Follow-up interviews are being conducted at 18-month intervals. Of the 1422 participants at baseline, 356 were from BC (25%), 713 from Ontario (50%), 353 from Quebec (25%). The median age of the participants at baseline was 43 years (range, 16

Atypical depression is more common than melancholic in fibromyalgia: an observational cohort study.

PubMed

Ross, Rebecca L; Jones, Kim D; Ward, Rachel L; Wood, Lisa J; Bennett, Robert M

2010-06-14

It has been postulated that atypical and melancholic depression subtypes exist in depressed fibromyalgia (FM) patients, yet no study has empirically tested this hypothesis. The purpose of this study is to determine whether major depressive disorder (MDD) with atypical features and MDD with melancholic features occurs in a FM sample and to describe their demographic, clinical and diagnostic characteristics. An observational cohort study using a descriptive cross-sectional design recruited a convenience sample of 76 outpatients with FM from an academic rheumatology clinic and a community mental health practice. Diagnoses of FM were confirmed using the 1990 ACR classification guidelines. Diagnoses of MDD and diagnostic subtypes were determined using the DSM-IV-TR criteria. Clinical characteristics were measured using the Fibromyalgia Impact Questionnaire, Structured Interview Guide for the Hamilton Depression Rating Scale with Atypical Depression Supplement and other standardized instruments. Odds ratios were computed on subtype-specific diagnostic criteria. Correlations assessed associations between subtype diagnoses and diagnostic criteria. Of the 76 subjects with FM, 11.8% (n = 9) were euthymic, 52.6% (n = 40) met diagnostic criteria for MDD with atypical features and 35.6% (n = 27) for MDD with melancholic features. Groups did not differ on demographic characteristics except for gender (p = 0.01). The non-depressed and atypical groups trended toward having a longer duration of FM symptoms (18.05 yrs. +/- 12.83; 20.36 yrs. +/- 15.07) compared to the melancholic group (14.11 yrs. +/- 8.82; p = 0.09). The two depressed groups experienced greater severity on all clinical features compared to the non-depressed group. The atypical group did not differ clinically from the melancholic group except the latter experienced greater depression severity (p = 0.001). The atypical group demonstrated the highest prevalence and correlations with atypical-specific diagnostic

Safety of a killed oral cholera vaccine (Shanchol) in pregnant women in Malawi: an observational cohort study.

PubMed

Ali, Mohammad; Nelson, Allyson; Luquero, Francisco J; Azman, Andrew S; Debes, Amanda K; M'bang'ombe, Maurice Mwesawina; Seyama, Linly; Kachale, Evans; Zuze, Kingsley; Malichi, Desire; Zulu, Fatima; Msyamboza, Kelias Phiri; Kabuluzi, Storn; Sack, David A

2017-05-01

Pregnancy increases the risk of harmful effects from cholera for both mothers and their fetuses. A killed oral cholera vaccine, Shanchol (Shantha Biotechnics, Hydrabad, India), can protect against the disease for up to 5 years. However, cholera vaccination campaigns have often excluded pregnant women because of insufficient safety data for use during pregnancy. We did an observational cohort study to assess the safety of Shanchol during pregnancy. This observational cohort study was done in two adjacent districts (Nsanje and Chikwawa) in Malawi. Individuals older than 1 year in Nsanje were offered oral cholera vaccine during a mass vaccination campaign between March 30 and April 30, 2015, but no vaccines were administered in Chikwawa. We enrolled women who were exposed to oral cholera vaccine during pregnancy in Nsanje district, and women who were pregnant in Chikwawa district (and thus not exposed to oral cholera vaccine) during the same period. The primary endpoint of our analysis was pregnancy loss (spontaneous miscarriage or stillbirth), and the secondary endpoints were neonatal deaths and malformations. We evaluated these endpoints using log-binomial regression, adjusting for the imbalanced baseline characteristics between the groups. This study is registered with ClinicalTrials.gov, number NCT02499172. We recruited 900 women exposed to oral cholera vaccine and 899 women not exposed to the vaccine between June 16 and Oct 10, 2015, and analysed 835 in each group. 361 women exposed to the vaccine and 327 not exposed to the vaccine were recruited after their pregnancies had ended. The incidence of pregnancy loss was 27·54 (95% CI 18·41-41·23) per 1000 pregnancies among those exposed to the vaccine and 21·56 (13·65-34·04) per 1000 among those not exposed. The adjusted relative risk for pregnancy loss among those exposed to oral cholera vaccine was 1·24 (95% CI 0·64-2·43; p=0·52) compared with those not exposed to the vaccine. The neonatal mortality rate

Can Psychopathology at Age 7 Be Predicted from Clinical Observation at One Year? Evidence from the ALSPAC Cohort

ERIC Educational Resources Information Center

Allely, C. S.; Doolin, O.; Gillberg, C.; Gillberg, I. C.; Puckering, C.; Smillie, M.; McConnachie, A.; Heron, J.; Golding, J.; Wilson, P.

2012-01-01

One of the challenges of developmental psychopathology is to determine whether identifiable pathways to developmental disorders exist in the first months or years of life. Early identification of such disorders poses a similar challenge for clinical services. Using data from a large contemporary birth cohort, we examined whether psychopathology at…

Developing adaptive interventions for adolescent substance use treatment settings: protocol of an observational, mixed-methods project.

PubMed

Grant, Sean; Agniel, Denis; Almirall, Daniel; Burkhart, Q; Hunter, Sarah B; McCaffrey, Daniel F; Pedersen, Eric R; Ramchand, Rajeev; Griffin, Beth Ann

2017-12-19

Over 1.6 million adolescents in the United States meet criteria for substance use disorders (SUDs). While there are promising treatments for SUDs, adolescents respond to these treatments differentially in part based on the setting in which treatments are delivered. One way to address such individualized response to treatment is through the development of adaptive interventions (AIs): sequences of decision rules for altering treatment based on an individual's needs. This protocol describes a project with the overarching goal of beginning the development of AIs that provide recommendations for altering the setting of an adolescent's substance use treatment. This project has three discrete aims: (1) explore the views of various stakeholders (parents, providers, policymakers, and researchers) on deciding the setting of substance use treatment for an adolescent based on individualized need, (2) generate hypotheses concerning candidate AIs, and (3) compare the relative effectiveness among candidate AIs and non-adaptive interventions commonly used in everyday practice. This project uses a mixed-methods approach. First, we will conduct an iterative stakeholder engagement process, using RAND's ExpertLens online system, to assess the importance of considering specific individual needs and clinical outcomes when deciding the setting for an adolescent's substance use treatment. Second, we will use results from the stakeholder engagement process to analyze an observational longitudinal data set of 15,656 adolescents in substance use treatment, supported by the Substance Abuse and Mental Health Services Administration, using the Global Appraisal of Individual Needs questionnaire. We will utilize methods based on Q-learning regression to generate hypotheses about candidate AIs. Third, we will use robust statistical methods that aim to appropriately handle casemix adjustment on a large number of covariates (marginal structural modeling and inverse probability of treatment weights

Radiation exposure due to local fallout from Soviet atmospheric nuclear weapons testing in Kazakhstan: solid cancer mortality in the Semipalatinsk historical cohort, 1960-1999.

PubMed

Bauer, Susanne; Gusev, Boris I; Pivina, Ludmila M; Apsalikov, Kazbek N; Grosche, Bernd

2005-10-01

Little information is available on the health effects of exposures to fallout from Soviet nuclear weapons testing and on the combined external and internal environmental exposures that have resulted from these tests. This paper reports the first analysis of the Semipalatinsk historical cohort exposed in the vicinity of the Semipalatinsk nuclear test site, Kazakhstan. The cohort study, which includes 19,545 inhabitants of exposed and comparison villages of the Semipalatinsk region, was set up in the 1960s and comprises 582,750 person-years of follow-up between 1960 and 1999. Cumulative effective radiation dose estimates in this cohort range from 20 mSv to approximately 4 Sv. Rates of mortality and cancer mortality in the exposed group substantially exceeded those of the comparison group. Dose-response analyses within the exposed group confirmed a significant trend with dose for all solid cancers (P < 0.0001) and for digestive and respiratory cancers (P = 0.0255 and P < 0.0001), whereas no consistent dose-response trend was found for all causes of death (P = 0.4296). Regarding specific cancer sites, a significant trend with dose was observed for lung cancer (P = 0.0001), stomach cancer (P = 0.0050), and female breast cancer (P = 0.0040) as well as for esophagus cancer in women (P = 0.0030). The excess relative risk per sievert for all solid cancers combined was 1.77 (1.35; 2.27) based on the total cohort data, yet a selection bias regarding the comparison group could not be entirely ruled out. The excess relative risk per sievert based on the cohort's exposed group was 0.81 (0.46; 1.33) for all solid cancers combined and thus still exceeds current risk estimates from the Life Span Study. Future epidemiological assessments based on this cohort will benefit from extension of follow-up and ongoing validation of dosimetric data.

Spontaneous hypothermia on intensive care unit admission is a predictor of unfavorable neurological outcome in patients after resuscitation: an observational cohort study.

PubMed

den Hartog, Alexander W; de Pont, Anne-Cornélie J M; Robillard, Laure B M; Binnekade, Jan M; Schultz, Marcus J; Horn, Janneke

2010-01-01

A large number of patients resuscitated for primary cardiac arrest arrive in the intensive care unit (ICU) with a body temperature < 35.0 degrees C. The aim of this observational cohort study was to determine the association between ICU admission temperature and neurological outcome in this patient group. Demographics and parameters influencing neurological outcome were retrieved from the charts of all patients resuscitated for primary cardiac arrest and treated with induced mild hypothermia in our ICU from January 2006 until January 2008. Patients were divided into two groups according to their body temperature on ICU admission: a hypothermia group (< 35.0 degrees C) and a non-hypothermia group (>or=35.0 degrees C). Neurological outcome after six months was assessed by means of the Glasgow Outcome Score (GOS), with GOS 1 to 3 defined as unfavorable and GOS 4 to 5 as favorable. A logistic regression model was used to analyze the influence of the different parameters on neurological outcome. The data of 105 consecutive patients resuscitated for primary cardiac arrest and treated with induced mild hypothermia were analyzed. Median ICU admission temperature was 35.1 degrees C (interquartile range (IQR) 34.3 to 35.7). After six months, 61% of the patients had an unfavorable outcome (59% died and 2% were severely disabled), whereas 39% had a favorable outcome (moderate disability or good recovery). Among patients with spontaneous hypothermia on ICU admission, the percentage with unfavorable outcome was higher (69% versus 50%, P = 0.05). Logistic regression showed that age, acute physiology and chronic health evaluation (APACHE) II and sequential organ failure assessment (SOFA) scores and spontaneous hypothermia on ICU admission all had an increased odds ratio (OR) for an unfavorable outcome after six months. Spontaneous hypothermia had the strongest association with unfavorable outcome (OR 2.6, 95% CI (confidence interval) 1.1 to 5.9), which became even stronger after

Environmental tobacco smoke exposure and health disparities: 8-year longitudinal findings from a large cohort of Thai adults.

PubMed

Tran, Thanh Tam; Yiengprugsawan, Vasoontara; Chinwong, Dujrudee; Seubsman, Sam-Ang; Sleigh, Adrian

2015-12-08

In rich countries, smokers, active or passive, often belong to disadvantaged groups. Less is known of tobacco patterns in the developing world. Hence, we seek out to investigate mental and physical health consequences of smoke exposure as well as tobacco-related inequality in transitional middle-income Thailand. We studied a nationwide cohort of 87,151 middle-aged and older adults that we have been following for eight years (2005-2013) for emerging chronic diseases. Logistic regression was used to identify attributes associated with passive smoke exposure. Longitudinal associations between smoke exposure and wellbeing (SF-8) or psychological distress (Kessler 6) were investigated with multiple linear regression or multivariate logistic regression analysis. A high proportion of cohort members, especially females, were passive smokers at home and at public transport stations; males were more exposed at workplace and recreational places. We observed a social gradient with more passive smoking in poorer people. We also observed a dose response relationship linking graded smoke exposures (current, former, passive, non-exposed) to less wellbeing and more psychological distress (p-trend < 0.001). Female smokers in general had less wellbeing and more distress. Our findings add to current knowledge on the impact of active and passive smoking on health in a transitional economy. Promotion of smoking cessation programs both in public and at home could also potentially reduce adverse disparities in health and wellbeing in middle and lower income settings such as Thailand.

Dose relations between goal setting, theory-based correlates of goal setting and increases in physical activity during a workplace trial.

PubMed

Dishman, Rod K; Vandenberg, Robert J; Motl, Robert W; Wilson, Mark G; DeJoy, David M

2010-08-01

The effectiveness of an intervention depends on its dose and on moderators of dose, which usually are not studied. The purpose of the study is to determine whether goal setting and theory-based moderators of goal setting had dose relations with increases in goal-related physical activity during a successful workplace intervention. A group-randomized 12-week intervention that included personal goal setting was implemented in fall 2005, with a multiracial/ethnic sample of employees at 16 geographically diverse worksites. Here, we examined dose-related variables in the cohort of participants (N = 664) from the 8 worksites randomized to the intervention. Participants in the intervention exceeded 9000 daily pedometer steps and 300 weekly minutes of moderate-to-vigorous physical activity (MVPA) during the last 6 weeks of the study, which approximated or exceeded current public health guidelines. Linear growth modeling indicated that participants who set higher goals and sustained higher levels of self-efficacy, commitment and intention about attaining their goals had greater increases in pedometer steps and MVPA. The relation between change in participants' satisfaction with current physical activity and increases in physical activity was mediated by increases in self-set goals. The results show a dose relation of increased physical activity with changes in goal setting, satisfaction, self-efficacy, commitment and intention, consistent with goal-setting theory.

Beyond main effects of gene-sets: harsh parenting moderates the association between a dopamine gene-set and child externalizing behavior.

PubMed

Windhorst, Dafna A; Mileva-Seitz, Viara R; Rippe, Ralph C A; Tiemeier, Henning; Jaddoe, Vincent W V; Verhulst, Frank C; van IJzendoorn, Marinus H; Bakermans-Kranenburg, Marian J

2016-08-01

In a longitudinal cohort study, we investigated the interplay of harsh parenting and genetic variation across a set of functionally related dopamine genes, in association with children's externalizing behavior. This is one of the first studies to employ gene-based and gene-set approaches in tests of Gene by Environment (G × E) effects on complex behavior. This approach can offer an important alternative or complement to candidate gene and genome-wide environmental interaction (GWEI) studies in the search for genetic variation underlying individual differences in behavior. Genetic variants in 12 autosomal dopaminergic genes were available in an ethnically homogenous part of a population-based cohort. Harsh parenting was assessed with maternal (n = 1881) and paternal (n = 1710) reports at age 3. Externalizing behavior was assessed with the Child Behavior Checklist (CBCL) at age 5 (71 ± 3.7 months). We conducted gene-set analyses of the association between variation in dopaminergic genes and externalizing behavior, stratified for harsh parenting. The association was statistically significant or approached significance for children without harsh parenting experiences, but was absent in the group with harsh parenting. Similarly, significant associations between single genes and externalizing behavior were only found in the group without harsh parenting. Effect sizes in the groups with and without harsh parenting did not differ significantly. Gene-environment interaction tests were conducted for individual genetic variants, resulting in two significant interaction effects (rs1497023 and rs4922132) after correction for multiple testing. Our findings are suggestive of G × E interplay, with associations between dopamine genes and externalizing behavior present in children without harsh parenting, but not in children with harsh parenting experiences. Harsh parenting may overrule the role of genetic factors in externalizing behavior. Gene-based and gene-set

Non-cancer morbidity among Estonian Chernobyl cleanup workers: a register-based cohort study.

PubMed

Rahu, Kaja; Bromet, Evelyn J; Hakulinen, Timo; Auvinen, Anssi; Uusküla, Anneli; Rahu, Mati

2014-05-14

To examine non-cancer morbidity in the Estonian Chernobyl cleanup workers cohort compared with the population sample with special attention to radiation-related diseases and mental health disorders. Register-based cohort study. Estonia. An exposed cohort of 3680 men (cleanup workers) and an unexposed cohort of 7631 men (population sample) were followed from 2004 to 2012 through the Population Registry and Health Insurance Fund database. Morbidity in the exposed cohort compared with the unexposed controls was estimated in terms of rate ratio (RR) with 95% CIs using Poisson regression models. Elevated morbidity in the exposed cohort was found for diseases of the nervous system, digestive system, musculoskeletal system, ischaemic heart disease and for external causes. The most salient excess risk was observed for thyroid diseases (RR=1.69; 95% CI 1.38 to 2.07), intentional self-harm (RR=1.47; 95% CI 1.04 to 2.09) and selected alcohol-related diagnoses (RR=1.25; 95% CI 1.12 to 1.39). No increase in morbidity for stress reactions, depression, headaches or sleep disorders was detected. No obvious excess morbidity consistent with biological effects of radiation was seen in the exposed cohort, with the possible exception of benign thyroid diseases. Increased alcohol-induced morbidity may reflect alcohol abuse, and could underlie some of the higher morbidity rates. Mental disorders in the exposed cohort were probably under-reported. The future challenge will be to study mental and physical comorbidities in the Chernobyl cleanup workers cohort. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Site-specific cancer risk in the Baltic cohort of Chernobyl cleanup workers, 1986–2007

PubMed Central

Rahu, Kaja; Hakulinen, Timo; Smailyte, Giedre; Stengrevics, Aivars; Auvinen, Anssi; Inskip, Peter D.; Boice, John D.; Rahu, Mati

2013-01-01

Objective To assess site-specific cancer risk in the Baltic cohort of Chernobyl cleanup workers 1986–2007. Methods The Baltic cohort includes 17,040 men from Estonia, Latvia and Lithuania who participated in the environmental cleanup after the accident at the Chernobyl Nuclear Power Station in 1986–1991, and who were followed for cancer incidence until the end of 2007. Cancer cases diagnosed in the cohort and in the male population of each country were identified from the respective national cancer registers. The proportional incidence ratio (PIR) with 95% confidence interval (CI) was used to estimate the site-specific cancer risk in the cohort. For comparison and as it was possible, the site-specific standardized incidence ratio (SIR) was calculated for the Estonian sub-cohort, which was not feasible for the other countries. Results Overall, 756 cancer cases were reported during 1986–2007. A higher proportion of thyroid cancers in relation to the male population was found (PIR=2.76; 95%CI 1.63–4.36), especially among those who started their mission shortly after the accident, in April–May 1986 (PIR=6.38; 95% CI 2.34–13.89). Also, an excess of oesophageal cancers was noted (PIR=1.52; 95% CI 1.06–2.11). No increased PIRs for leukaemia or radiation-related cancer sites combined were observed. PIRs and SIRs for the Estonian sub-cohort demonstrated the same site-specific cancer risk pattern. Conclusion Consistent evidence of an increase in radiation-related cancers in the Baltic cohort was not observed with the possible exception of thyroid cancer, where conclusions are hampered by known medical examination including thyroid screening among cleanup workers. PMID:23683549

Establishment and baseline characteristics of a nationwide Danish cohort of patients with Ehlers-Danlos syndrome.

PubMed

Kulas Søborg, Marie-Louise; Leganger, Julie; Quitzau Mortensen, Laura; Rosenberg, Jacob; Burcharth, Jakob

2017-05-01

The aim of this study was to investigate national prevalence, general demographic characteristics and survival of Danish patients with Ehlers-Danlos syndrome (EDS). A population-based cohort study was conducted using a database consisting of the entire Danish population alive at any given time between 1 January 2000 and 31 December 2012, based upon longitudinal Danish national registers. All patients with EDS were identified, and the cohort was described by disease prevalence, basic demographic characteristics, mean age at death and mortality for the observational period of 13 years. The cohort held 1427 unique persons with EDS, giving a national prevalence of 0.02%. The EDS population had a mean ( s . d .) age of 34.9 (18.6) years and comprised 73.9% females and 26.1% males. Of the cohort, 95.9% originated from Denmark and 57% were unmarried. We found that 31.6% of the cohort received state-granted subsidies, of which 77% were in the form of early retirement pension. Regarding educational status, 28.1% of the EDS cohort had completed primary education (⩽10th grade) as their highest educational level, while 71.9% had completed a higher level. During the observation period, 42 patients died, with a mean ( s . d .) age at death of 53.6 (21.7) years. This study confirmed a small national prevalence of patients diagnosed with EDS and showed that the majority of patients diagnosed are female. The EDS cohort had a lower educational level, mean age and life expectancy compared with the background population and showed a predisposition for receiving state-granted subsidies. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Malaria increased the risk of stunting and wasting among young children in Ethiopia: Results of a cohort study.

PubMed

Gari, Taye; Loha, Eskindir; Deressa, Wakgari; Solomon, Tarekegn; Lindtjørn, Bernt

2018-01-01

Given the high prevalence of malnutrition in a malaria-endemic setting, improving nutritional status could serve as a tool to prevent malaria. However, the relationship between the two conditions remains unclear. Therefore, this study assessed the association between under-nutrition and malaria among a cohort of children aged 6 to 59 months old. Two cohorts of children were followed for 89 weeks in a rural Rift Valley area of Ethiopia. In the first approach (malaria-malnutrition), a cohort of 2,330 non-stunted and 4,204 non-wasted children were included to assess under-nutrition (outcome) based on their previous malaria status (exposure). In the second approach (malnutrition-malaria), a cohort of 4,468 children were followed-up to measure malaria (outcome), taking under-nutrition as an exposure. A weekly home visit was carried out to identify malaria cases. Four anthropometry surveys were conducted, and generalized estimating equation (GEE) method was used to measure the association between undernutrition and malaria. The prevalence of stunting was 44.9% in December 2014, 51.5% in August 2015, 50.7% in December 2015 and 48.1% in August 2016. We observed 103 cases with 118 episodes of malaria, 684 new stunting and 239 new wasting cases. The incidence rate per 10,000 weeks of observation was 3.8 for malaria, 50.4 for stunting and 8.2 for wasting. Children with malaria infection, [Adjusted Odds Ratio (AOR) = 1.9; 95% Confidence Interval (CI), 1.2-2.9)] and younger age (AOR = 1.3; 95% CI, 1.1-1.5) were more likely to be stunted. Furthermore, children with malaria infection (AOR = 8.5; 95% CI, 5.0-14.5) and young age group (AOR = 1.6; 95% CI, 1.2-2.1) were more likely to be wasted. However, stunting and wasting were not risk factors of subsequent malaria illness. Malaria infection was a risk factor for stunting and wasting, but stunting or wasting was not associated with subsequent malaria illness. As our study shows that malaria is a risk factor for stunting and

Time trend and age-period-cohort effect on kidney cancer mortality in Europe, 1981-2000.

PubMed

Pérez-Farinós, Napoleón; López-Abente, Gonzalo; Pastor-Barriuso, Roberto

2006-05-03

The incorporation of diagnostic and therapeutic improvements, as well as the different smoking patterns, may have had an influence on the observed variability in renal cancer mortality across Europe. This study examined time trends in kidney cancer mortality in fourteen European countries during the last two decades of the 20th century. Kidney cancer deaths and population estimates for each country during the period 1981-2000 were drawn from the World Health Organization Mortality Database. Age- and period-adjusted mortality rates, as well as annual percentage changes in age-adjusted mortality rates, were calculated for each country and geographical region. Log-linear Poisson models were also fitted to study the effect of age, death period, and birth cohort on kidney cancer mortality rates within each country. For men, the overall standardized kidney cancer mortality rates in the eastern, western, and northern European countries were 20, 25, and 53% higher than those for the southern European countries, respectively. However, age-adjusted mortality rates showed a significant annual decrease of -0.7% in the north of Europe, a moderate rise of 0.7% in the west, and substantial increases of 1.4% in the south and 2.0% in the east. This trend was similar among women, but with lower mortality rates. Age-period-cohort models showed three different birth-cohort patterns for both men and women: a decrease in mortality trend for those generations born after 1920 in the Nordic countries, a similar but lagged decline for cohorts born after 1930 in western and southern European countries, and a continuous increase throughout all birth cohorts in eastern Europe. Similar but more heterogeneous regional patterns were observed for period effects. Kidney cancer mortality trends in Europe showed a clear north-south pattern, with high rates on a downward trend in the north, intermediate rates on a more marked rising trend in the east than in the west, and low rates on an upward trend

Cadmium exposure and risk of lung cancer: a meta-analysis of cohort and case-control studies among general and occupational populations.

PubMed

Chen, Cheng; Xun, Pengcheng; Nishijo, Muneko; He, Ka

2016-09-01

The association between cadmium exposure and risk of lung cancer is still unclear. We quantitatively reviewed the observational studies that investigated the association between cadmium exposure and lung cancer risk in both general and occupational populations published through April 2015. The final data set is comprised of three cohort studies in the general population totaling 22,551 participants (354 events) with a mean follow-up of 15 years, five occupational cohort studies including 4205 individuals (180 events) with an average follow-up of 31 years, and three occupational case-control studies including 4740 cases and 6268 controls. Comparing the highest to the lowest category of cadmium exposure, the weighted relative risk and 95% confidence interval of lung cancer in the general population was 1.42 (95% CI (0.91, 2.23)); the weighted risk estimates (95% CIs) of lung cancer in three occupational cohort studies and three case-control studies were 0.68 (95% CI (0.33, 1.41)) and 1.61 (95% CI (0.94, 2.75)), respectively. No linear association was found. When comparing participants exposed to cadmium with non-exposed based on available data, the association became statistically significant. According to findings from this meta-analysis, the possibility that cadmium exposure may increase risk of lung cancer cannot be completely ruled out in either general or occupational population.

Sleep Disordered Breathing in Four Resource-Limited Settings in Peru: Prevalence, Risk Factors, and Association with Chronic Diseases.

PubMed

Schwartz, Noah G; Rattner, Adi; Schwartz, Alan R; Mokhlesi, Babak; Gilman, Robert H; Bernabe-Ortiz, Antonio; Miranda, J Jaime; Checkley, William

2015-09-01

Sleep disordered breathing (SDB) is a highly prevalent condition in high-income countries, with major consequences for cardiopulmonary health, public safety, healthcare utilization, and mortality. However, its prevalence and effect in low- and middle-income countries are less well known. We sought to determine the prevalence, risk factors, and comorbidities of SDB symptoms in four resource-limited settings. Cross-sectional analysis of the CRONICAS Cohort, a population-based age- and sex-stratified sample. Four resource-limited settings in Peru varying in altitude, urbanization, and air pollution. There were 2,682 adults aged 35 to 92 y. Self-reported SDB symptoms (habitual snoring, observed apneas, Epworth Sleepiness Scale), sociodemographics, medical history, anthropometrics, spirometry, blood biomarkers were reported. We found a high prevalence of habitual snoring (30.2%, 95% confidence interval [CI] 28.5-32.0%), observed apneas (20.9%, 95% CI 19.4-22.5%) and excessive daytime sleepiness (18.6%, 95% CI 17.1-20.1%). SDB symptoms varied across sites; prevalence and adjusted odds for habitual snoring were greatest at sea level, whereas those for observed apneas were greatest at high altitude. In multivariable analysis, habitual snoring was associated with older age, male sex, body mass index (BMI), and higher socioeconomic status; observed apneas were associated with BMI; and excessive daytime sleepiness was associated with older age, female sex, and medium socioeconomic status. Adjusted odds of cardiovascular disease, depression, and hypertension and total chronic disease burden increased progressively with the number of SDB symptoms. A threefold increase in the odds of having an additional chronic comorbid disease (adjusted odds ratio 3.57, 95% CI 2.18-5.84) was observed in those with all three versus no SDB symptoms. Sleep disordered breathing symptoms were highly prevalent, varied widely across four resource-limited settings in Peru, and exhibited strong

Microsurgery Versus Stereotactic Radiosurgery for Brain Arteriovenous Malformations: A Matched Cohort Study.

PubMed

Chen, Ching-Jen; Ding, Dale; Wang, Tony R; Buell, Thomas J; Ilyas, Adeel; Ironside, Natasha; Lee, Cheng-Chia; Kalani, M Yashar; Park, Min S; Liu, Kenneth C; Sheehan, Jason P

2018-05-12

Microsurgery (MS) and stereotactic radiosurgery (SRS) remain the preferred interventions for the curative treatment of brain arteriovenous malformations (AVM), but their relative efficacy remains incompletely defined. To compare the outcomes of MS to SRS for AVMs through a retrospective, matched cohort study. We evaluated institutional databases of AVM patients who underwent MS and SRS. MS-treated patients were matched, in a 1:1 ratio based on patient and AVM characteristics, to SRS-treated patients. Statistical analyses were performed to compare outcomes data between the 2 cohorts. The primary outcome was defined as AVM obliteration without a new permanent neurological deficit. The matched MS and SRS cohorts were each comprised of 59 patients. Both radiological (85 vs 11 mo; P < .001) and clinical (92 vs 12 mo; P < .001) follow-up were significantly longer for the SRS cohort. The primary outcome was achieved in 69% of each cohort. The MS cohort had a significantly higher obliteration rate (98% vs 72%; P = .001), but also had a significantly higher rate of new permanent deficit (31% vs 10%; P = .011). The posttreatment hemorrhage rate was significantly higher for the SRS cohort (10% for SRS vs 0% for MS; P = .027). In subgroup analyses of ruptured and unruptured AVMs, no significant differences between the primary outcomes were observed. For patients with comparable AVMs, MS and SRS afford similar rates of deficit-free obliteration. Nidal obliteration is more frequently achieved with MS, but this intervention also incurs a greater risk of new permanent neurological deficit.

Study protocol: the JEU cohort study--transversal multiaxial evaluation and 5-year follow-up of a cohort of French gamblers.

PubMed

Challet-Bouju, Gaëlle; Hardouin, Jean-Benoit; Vénisse, Jean-Luc; Romo, Lucia; Valleur, Marc; Magalon, David; Fatséas, Mélina; Chéreau-Boudet, Isabelle; Gorsane, Mohamed-Ali; Grall-Bronnec, Marie

2014-08-20

There is abundant literature on how to distinguish problem gambling (PG) from social gambling, but there are very few studies of the long-term evolution of gambling practice. As a consequence, the correlates of key state changes in the gambling trajectory are still unknown. The objective of the JEU cohort study is to identify the determinants of key state changes in the gambling practice, such as the emergence of a gambling problem, natural recovery from a gambling problem, resolution of a gambling problem with intermediate care intervention, relapses or care recourse. The present study was designed to overcome the limitations of previous cohort study on PG. Indeed, this longitudinal case-control cohort is the first which plans to recruit enough participants from different initial gambling severity levels to observe these rare changes. In particular, we plan to recruit three groups of gamblers: non-problem gamblers, problem gamblers without treatment and problem gamblers seeking treatment.Recruitment takes place in various gambling places, through the press and in care centers. Cohort participants are gamblers of both sexes who reported gambling on at least one occasion in the previous year and who were aged between 18 and 65. They were assessed through a structured clinical interview and self-assessment questionnaires at baseline and then once a year for five years. Data collection comprises sociodemographic characteristics, gambling habits (including gambling trajectory), the PG section of the DSM-IV, the South Oaks Gambling Screen, the Gambling Attitudes and Beliefs Survey - 23, the Mini International Neuropsychiatric Interview, the Wender-Utah Rating Scale-Child, the Adult ADHD Self-report Scale, somatic comorbidities (especially current treatment and Parkinson disease) and the Temperament and Character Inventory - 125. The JEU cohort study is the first study which proposes to identify the predictive factors of key state changes in gambling practice. This is

Sensitivity of Global Methane Bayesian Inversion to Surface Observation Data Sets and Chemical-Transport Model Resolution

NASA Astrophysics Data System (ADS)

Lew, E. J.; Butenhoff, C. L.; Karmakar, S.; Rice, A. L.; Khalil, A. K.

2017-12-01

Methane is the second most important greenhouse gas after carbon dioxide. In efforts to control emissions, a careful examination of the methane budget and source strengths is required. To determine methane surface fluxes, Bayesian methods are often used to provide top-down constraints. Inverse modeling derives unknown fluxes using observed methane concentrations, a chemical transport model (CTM) and prior information. The Bayesian inversion reduces prior flux uncertainties by exploiting information content in the data. While the Bayesian formalism produces internal error estimates of source fluxes, systematic or external errors that arise from user choices in the inversion scheme are often much larger. Here we examine model sensitivity and uncertainty of our inversion under different observation data sets and CTM grid resolution. We compare posterior surface fluxes using the data product GLOBALVIEW-CH4 against the event-level molar mixing ratio data available from NOAA. GLOBALVIEW-CH4 is a collection of CH4 concentration estimates from 221 sites, collected by 12 laboratories, that have been interpolated and extracted to provide weekly records from 1984-2008. Differently, the event-level NOAA data records methane mixing ratios field measurements from 102 sites, containing sampling frequency irregularities and gaps in time. Furthermore, the sampling platform types used by the data sets may influence the posterior flux estimates, namely fixed surface, tower, ship and aircraft sites. To explore the sensitivity of the posterior surface fluxes to the observation network geometry, inversions composed of all sites, only aircraft, only ship, only tower and only fixed surface sites, are performed and compared. Also, we investigate the sensitivity of the error reduction associated with the resolution of the GEOS-Chem simulation (4°×5° vs 2°×2.5°) used to calculate the response matrix. Using a higher resolution grid decreased the model-data error at most sites, thereby

Perioperative patient outcomes in the African Surgical Outcomes Study: a 7-day prospective observational cohort study.

PubMed

Biccard, Bruce M; Madiba, Thandinkosi E; Kluyts, Hyla-Louise; Munlemvo, Dolly M; Madzimbamuto, Farai D; Basenero, Apollo; Gordon, Christina S; Youssouf, Coulibaly; Rakotoarison, Sylvia R; Gobin, Veekash; Samateh, Ahmadou L; Sani, Chaibou M; Omigbodun, Akinyinka O; Amanor-Boadu, Simbo D; Tumukunde, Janat T; Esterhuizen, Tonya M; Manach, Yannick Le; Forget, Patrice; Elkhogia, Abdulaziz M; Mehyaoui, Ryad M; Zoumeno, Eugene; Ndayisaba, Gabriel; Ndasi, Henry; Ndonga, Andrew K N; Ngumi, Zipporah W W; Patel, Ushmah P; Ashebir, Daniel Zemenfes; Antwi-Kusi, Akwasi A K; Mbwele, Bernard; Sama, Hamza Doles; Elfiky, Mahmoud; Fawzy, Maher A; Pearse, Rupert M

2018-04-21

There is a need to increase access to surgical treatments in African countries, but perioperative complications represent a major global health-care burden. There are few studies describing surgical outcomes in Africa. We did a 7-day, international, prospective, observational cohort study of patients aged 18 years and older undergoing any inpatient surgery in 25 countries in Africa (the African Surgical Outcomes Study). We aimed to recruit as many hospitals as possible using a convenience sampling survey, and required data from at least ten hospitals per country (or half the surgical centres if there were fewer than ten hospitals) and data for at least 90% of eligible patients from each site. Each country selected one recruitment week between February and May, 2016. The primary outcome was in-hospital postoperative complications, assessed according to predefined criteria and graded as mild, moderate, or severe. Data were presented as median (IQR), mean (SD), or n (%), and compared using t tests. This study is registered on the South African National Health Research Database (KZ_2015RP7_22) and ClinicalTrials.gov (NCT03044899). We recruited 11 422 patients (median 29 [IQR 10-70]) from 247 hospitals during the national cohort weeks. Hospitals served a median population of 810 000 people (IQR 200 000-2 000 000), with a combined number of specialist surgeons, obstetricians, and anaesthetists totalling 0·7 (0·2-1·9) per 100 000 population. Hospitals did a median of 212 (IQR 65-578) surgical procedures per 100 000 population each year. Patients were younger (mean age 38·5 years [SD 16·1]), with a lower risk profile (American Society of Anesthesiologists median score 1 [IQR 1-2]) than reported in high-income countries. 1253 (11%) patients were infected with HIV, 6504 procedures (57%) were urgent or emergent, and the most common procedure was caesarean delivery (3792 patients, 33%). Postoperative complications occurred in 1977 (18·2%, 95% CI 17·4-18·9

Occupational variation in incidence of bladder cancer: a comparison of population-representative cohorts from Nordic countries and Canada.

PubMed

Hadkhale, Kishor; MacLeod, Jill; Demers, Paul A; Martinsen, Jan Ivar; Weiderpass, Elisabete; Kjaerheim, Kristina; Lynge, Elsebeth; Sparen, Pär; Tryggvadottir, Laufey; Anne Harris, M; Tjepkema, Michael; Peters, Paul A; Pukkala, Eero

2017-08-04

The objective of this study was to compare occupational variation of the risk of bladder cancer in the Nordic countries and Canada. In the Nordic Occupational Cancer study (NOCCA), 73 653 bladder cancer cases were observed during follow-up of 141.6 million person-years. In the Canadian Census Health and Environment Cohort (CanCHEC), 8170 cases were observed during the follow-up of 36.7 million person-years. Standardised incidence ratios with 95% CI were estimated for 53 occupations in the NOCCA cohort and HR with 95% CIs were estimated for 42 occupations in the CanCHEC. Elevated risks of bladder cancer were observed among hairdressers, printers, sales workers, plumbers, painters, miners and laundry workers. Teachers and agricultural workers had reduced risk of bladder cancer in both cohorts. Chimney-sweeps, tobacco workers and waiters had about 1.5-fold risk in the Nordic countries; no risk estimates for these categories were given from the CanCHEC cohort. We observed different occupational patterns in risk of bladder cancer in Nordic countries and Canada. The only occupation with similarly increased risk was observed among sales workers. Differences in smoking across occupational groups may explain some, but not all, of this variation. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

The role of birth cohorts in studies of adult health: the New York women's birth cohort.

PubMed

Terry, Mary Beth; Flom, Julie; Tehranifar, Parisa; Susser, Ezra

2009-09-01

Epidemiological studies investigating associations between early life factors and adult health are often limited to studying exposures that can be reliably recalled in adulthood or obtained from existing medical records. There are few US studies with detailed data on the pre- and postnatal environment whose study populations are now in adulthood; one exception is the Collaborative Perinatal Project (CPP). We contacted former female participants of the New York site of the CPP who were born from 1959 to 1963 and were prospectively followed for 7 years to examine whether the pre- and postnatal environment is associated with adult health in women 40 years after birth. The New York CPP cohort is particularly diverse; at enrolment, the race/ethnicity distribution of mothers was approximately 30% White, 40% Black and 30% Puerto Rican. Of the 841 eligible women, we successfully traced 375 women (45%) and enrolled 262 women (70% of those traced). Baseline data were available for all eligible women, and we compared those who participated with the remaining cohort (n = 579). Higher family socio-economic status at age 7, availability of maternal social security number, and White race/ethnicity were statistically significantly associated with a higher probability of tracing. Of those traced, race/ethnicity was associated with participation, with Blacks and Puerto Ricans less likely to participate than Whites (OR = 0.5, 95% CI 0.3, 0.8, and OR = 0.5, 95% CI 0.3, 1.0, respectively). In addition, higher weight at 7 years was associated with lower participation (OR = 0.95, 95% CI 0.92, 0.99), but this association was observed only among the non-White participants. None of the other maternal characteristics, infant or early childhood growth measures was associated with participation or with tracing, either overall or within each racial/ethnic subgroup. Daughters' recall of early life factors such as pre-eclampsia (sensitivity = 24%) and birthweight were generally poor, with the

RADAR study: protocol for an observational cohort study to identify early warning signals on the pathways to alcohol use disorder.

PubMed

Slade, Tim; Swift, Wendy; Mewton, Louise; Kypri, Kypros; Lynskey, Michael T; Butterworth, Peter; Tibbetts, Joel; McCraw, Stacey; Upton, Emily

2017-08-21

Harmful alcohol consumption, particularly alcohol use disorder (AUD), is a worldwide health priority, contributing substantially to global morbidity and mortality. The peak age of onset of AUD is 18-24, thus a deeper understanding of the young adult experience is vital if we are to identify modifiable risk factors and intervene early in the developmental course of this disabling disorder. Critical unanswered questions include: How soon after drinking initiation do AUD symptoms begin to emerge? Which symptoms come first? Do the symptoms unfold in a predictable pattern? In what ways do the emerging symptoms interact with individual, peer, family and environmental risk factors to impact on the transition to disorder? The proposed RADAR study will examine the prospective development of AUD symptoms over the young adulthood (18-24) years. We will capitalise on an existing cohort of 1911 community-based adolescents who were recruited at age 13 and have completed a baseline and five annual follow-up assessments as part of an observational cohort study. We will interview these adolescents every 6 months between the ages of 19 and 23 to derive monthly histories of both alcohol use and AUD symptomatology, along with a comprehensive battery of risk and protective factor scales hypothesised to predict the emergence and course of AUD. The results of this study will inform the natural history of AUD and will be used to identify specific targets for prevention and early intervention of AUD. Ethical approval has already been granted for the study (UNSW HREC 10144). We will disseminate the results of the study through published manuscripts, conferences and seminar presentations. Data used in published manuscripts will be made available through a suitable online repository (eg, Dryad-datadryad.org). © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly

Making Facilitation Work: The Challenges on an International DBA Action Learning Set

ERIC Educational Resources Information Center

OFarrell, Jack

2018-01-01

This account relates my experiences as facilitator of an action learning set on a DBA cohort comprising international students and myself. It outlines the reasons for my selection as facilitator and describes my initial expectations and assumptions of action learning. I chart the difficulty in separating the 'what' of my own research from the…

[Laterality of upper extremity movements in infancy: observations at 4 and 9 months of age].

PubMed

Shiotani, Yuka; Matsuzawa, Shigeyuki; Ikeda, Hiroko; Sawada, Akiko; Okada, Masako; Kutsuki, Aya; Tomiwa, Kiyotaka

2010-07-01

This study investigated the process involved in the lateralization of movements during infancy by observing upper extremity movements in a laboratory setting. Reaching for flying rings, balls, mini toy cars, and small round cookies were observed and recorded by videotape at 4 and 9 months of age. The subjects were 202 infants who participated in Japan Children's Study, a cohort study on the development of sociability. Infants reached for objects significantly more frequently at 9 months (98%) than at 4 months (40%) (p<0.001). Though the lateral preference in reaching for balls at 4 months was ambiguous, reaching for toy cars was performed more frequently with the right hand at 9 months (50%) than with the left one (19%) (p<0.01). Lateralization of the upper extremity movements is thought to appear by 9 months.

Colorectal cancer health services research study protocol: the CCR-CARESS observational prospective cohort project.

PubMed

Quintana, José M; Gonzalez, Nerea; Anton-Ladislao, Ane; Redondo, Maximino; Bare, Marisa; Fernandez de Larrea, Nerea; Briones, Eduardo; Escobar, Antonio; Sarasqueta, Cristina; Garcia-Gutierrez, Susana; Aguirre, Urko

2016-07-08

Colorectal cancers are one of the most common forms of malignancy worldwide. But two significant areas of research less studied deserve attention: health services use and development of patient stratification risk tools for these patients. a prospective multicenter cohort study with a follow up period of up to 5 years after surgical intervention. Participant centers: 22 hospitals representing six autonomous communities of Spain. Participants/Study population: Patients diagnosed with colorectal cancer that have undergone surgical intervention and have consented to participate in the study between June 2010 and December 2012. Variables collected include pre-intervention background, sociodemographic parameters, hospital admission records, biological and clinical parameters, treatment information, and outcomes up to 5 years after surgical intervention. Patients completed the following questionnaires prior to surgery and in the follow up period: EuroQol-5D, EORTC QLQ-C30 (The European Organization for Research and Treatment of Cancer quality of life questionnaire) and QLQ-CR29 (module for colorectal cancer), the Duke Functional Social Support Questionnaire, the Hospital Anxiety and Depression Scale, and the Barthel Index. The main endpoints of the study are mortality, tumor recurrence, major complications, readmissions, and changes in health-related quality of life at 30 days and at 1, 2, 3 and 5 years after surgical intervention. In relation to the different endpoints, predictive models will be used by means of multivariate logistic models, Cox or linear mixed-effects regression models. Simulation models for the prediction of discrete events in the long term will also be used, and an economic evaluation of different treatment strategies will be performed through the use of generalized linear models. The identification of potential risk factors for adverse events may help clinicians in the clinical decision making process. Also, the follow up by 5 years of this

Effect of breast-feeding on the development of atopic dermatitis during the first 3 years of life--results from the GINI-birth cohort study.

PubMed

Laubereau, Birgit; Brockow, Inken; Zirngibl, Angelika; Koletzko, Sibylle; Gruebl, Armin; von Berg, Andrea; Filipiak-Pittroff, Birgit; Berdel, Dietrich; Bauer, Carl Peter; Reinhardt, Dietrich; Heinrich, Joachim; Wichmann, H-Erich

2004-05-01

To investigate if exclusive breast-feeding for 4 months is associated with atopic dermatitis during the first 3 years of life. Data on 3903 children were taken from yearly parental-administered questionnaires from a birth cohort study in Germany (recruited 1995-1998) comprised of a noninterventional (NI) and an interventional (I) subgroup. Outcomes were physician-diagnosed atopic dermatitis (AD) and itchy rash. Multiple logistic regression was performed for the entire cohort and stratified by family history of allergy and by study group adjusting for a fixed set of risk factors for allergies. Exclusive breast-feeding (52 % of children) was not associated with higher risk for AD either in the entire cohort (OR(adj,) 0.95; 95% CI, 0.79-1.14) or if stratified by family history of AD. In the I subgroup, but not in the NI subgroup, exclusive breast-feeding showed a significant protective effect on AD if compared with conventional cow's milk formula (OR(adj), 0.64; 95% CI, 0.45-0.90). These findings do not support the hypothesis that exclusive breast-feeding is a risk factor for development of atopic dermatitis but is protective if compared with conventional cow's milk. Observational studies might not be able to effectively control for selection bias and reverse causation.

Educational expansion and the education gradient in health: A hierarchical age-period-cohort analysis.

PubMed

Delaruelle, Katrijn; Buffel, Veerle; Bracke, Piet

2015-11-01

Researchers have recently been investigating the temporal variation in the educational gradient in health. While there is abundant literature concerning age trajectories, theoretical knowledge about cohort differences is relatively limited. Therefore, in analogy with the life course perspective, we introduce two contrasting cohort-specific hypotheses. The diminishing health returns hypothesis predicts a decrease in educational disparities in health across cohorts. By contrast, the cohort accretion hypothesis suggests that the education-health gap will be more pronounced among younger cohorts. To shed light on this, we perform a hierarchical age-period-cohort analysis (HAPC), using data from a subsample of individuals between 25 and 85 years of age (N = 232,573) from 32 countries in the European Social Survey (six waves: 2002-2012). The analysis leads to three important conclusions. First, we observe a widening health gap between different educational levels over the life course. Second, we find that these educational differences in the age trajectories of health seem to strengthen with each successive birth cohort. However, the two age-related effects disappear when we control for employment status, household income, and family characteristics. Last, when adjusting for these mediators, we reveal evidence to support the diminishing health returns hypothesis, implying that it is primarily the direct association between education and health that decreases across cohorts. This finding raises concerns about potential barriers to education being a vehicle for empowerment and the promotion of health. Copyright © 2015 Elsevier Ltd. All rights reserved.

Myocardial injury after noncardiac surgery-incidence and predictors from a prospective observational cohort study at an Indian tertiary care centre.

PubMed

George, Rubin; Menon, Vidya P; Edathadathil, Fabia; Balachandran, Sabarish; Moni, Merlin; Sathyapalan, Dipu; Prasanna, Preetha; S, Gokuldas; Paul, Jerry; K K, Chandrababu; Kumar, Lakshmi; Pillai, Ashok

2018-05-01

Asymptomatic myocardial injury following noncardiac surgery (MINS) is an independent predictor of 30-day mortality and may go unrecognized based on standard diagnostic definition for myocardial infarction (MI). Given lack of published research on MINS in India, our study aims to determine incidence of MINS in patients undergoing noncardiac surgery at our tertiary care hospital, and evaluate the clinical characteristics including 30-day outcome.The prospective observational study included patients >65 years or >45 years with either hypertension (HTN), diabetes mellitus (DM), coronary artery disease (CAD), cerebrovascular accident (CVA), or peripheral arterial disease undergoing noncardiac surgery. MINS was peak troponin level of ≥0.03 ng/dL at 12-hour or 24-hour postoperative. All patients were followed for 30 days postoperatively. Predictors of MINS and mortality were analyzed using multivariate logistic regression. Patients categorized based on peak troponin cut-off values determined by receiver operating characteristic curve were analyzed by Kaplan-Meir test to compare the survival of patients between the groups.Among 1075 patients screened during 34-month period, the incidence of MINS was 17.5% (188/1075). Patients with DM, CAD, or who underwent peripheral nerve block anaesthesia were 1.5 (P < .01), 2 (P < .001), and 12 (P < .001) times, respectively, more likely to develop MINS than others. Patients with heart rates ≥96 bpm before induction of anesthesia were significantly associated with MINS (P = .005) and mortality (P = .02). The 30-day mortality in MINS cohort was 11.7% (22/188, 95% CI 7.5%-17.2%) vs 2.5% (23/887, 95% CI 1.7%-3.9%) in patients without MINS (P < .001). ECG changes (P = .002), peak troponin values >1 ng/mL (P = .01) were significantly associated with mortality. A peak troponin cut-off of >0.152 ng/mL predicted mortality among MINS patients at 72% sensitivity and 58% specificity. Lack of antithrombotic

A brief dietary assessment predicts executive dysfunction in an elderly cohort: results from the Einstein Aging Study

USDA-ARS?s Scientific Manuscript database

Objectives: To examine the association between diet and executive function, episodic memory and global verbal cognition in the Einstein Aging Study (EAS) cohort and determine whether race modifies this relationship. Design: Cross-sectional. Setting: Community. Participants: EAS participants without ...

Early assessment of cancer outcomes in New York City firefighters after the 9/11 attacks: an observational cohort study

PubMed Central

Zeig-Owens, Rachel; Webber, Mayris P; Hall, Charles B; Schwartz, Theresa; Jaber, Nadia; Weakley, Jessica; Rohan, Thomas E; Cohen, Hillel W; Derman, Olga; Aldrich, Thomas K; Kelly, Kerry; Prezant, David J

2017-01-01

Summary Background The attacks on the World Trade Center (WTC) on Sept 11, 2001 (9/11) created the potential for occupational exposure to known and suspected carcinogens. We examined cancer incidence and its potential association with exposure in the first 7 years after 9/11 in firefighters with health information before 9/11 and minimal loss to follow-up. Methods We assessed 9853 men who were employed as firefighters on Jan 1, 1996. On and after 9/11, person-time for 8927 firefighters was classified as WTC-exposed; all person-time before 9/11, and person-time after 9/11 for 926 non-WTC-exposed firefighters, was classified as non-WTC exposed. Cancer cases were confirmed by matches with state tumour registries or through appropriate documentation. We estimated the ratio of incidence rates in WTC-exposed firefighters to non-exposed firefighters, adjusted for age, race and ethnic origin, and secular trends, with the US National Cancer Institute Surveillance Epidemiology and End Results (SEER) reference population. CIs were estimated with overdispersed Poisson models. Additional analyses included corrections for potential surveillance bias and modified cohort inclusion criteria. Findings Compared with the general male population in the USA with a similar demographic mix, the standardised incidence ratios (SIRs) of the cancer incidence in WTC-exposed firefighters was 1·10 (95% CI 0·98–1·25). When compared with non-exposed firefighters, the SIR of cancer incidence in WTC-exposed firefighters was 1·19 (95% CI 0·96–1·47) corrected for possible surveillance bias and 1·32 (1·07–1·62) without correction for surveillance bias. Secondary analyses showed similar effect sizes. Interpretation We reported a modest excess of cancer cases in the WTC-exposed cohort. We remain cautious in our interpretation of this finding because the time since 9/11 is short for cancer outcomes, and the reported excess of cancers is not limited to specific organ types. As in any

Cohort profile: LIFEWORK, a prospective cohort study on occupational and environmental risk factors and health in the Netherlands.

PubMed

Reedijk, Marije; Lenters, Virissa; Slottje, Pauline; Pijpe, Anouk; Peeters, Petra H; Korevaar, Joke C; Bueno-de-Mesquita, Bas; Verschuren, W M Monique; Verheij, Robert A; Pieterson, Inka; van Leeuwen, Flora E; Rookus, Matti A; Kromhout, Hans; Vermeulen, Roel C H

2018-02-03

LIFEWORK is a large federated prospective cohort established in the Netherlands to quantify the health effects of occupational and environmental exposures. This cohort is also the Dutch contribution to the international Cohort Study of Mobile Phone Use and Health (COSMOS). In this paper, we describe the study design, ongoing data collection, baseline characteristics of participants and the repeatability of key questionnaire items. 88 466 participants were enrolled in three cohort studies in 2011-2012. Exposure information was collected by a harmonised core questionnaire, or modelled based on occupational and residential histories; domains include air pollution (eg, nitrogen dioxide (NO 2 ), particulate matter with diameter ≤2.5 µm (PM 2.5 )), noise, electromagnetic fields (EMF), mobile phone use, shift work and occupational chemical exposures. Chronic and subacute health outcomes are assessed by self-report and through linkage with health registries. Participants had a median age of 51 years at baseline (range 19-87), and the majority are female (90%), with nurses being over-represented. Median exposure levels of NO 2 , PM 2.5 , EMF from base stations and noise at the participants' home addresses at baseline were 22.9 µg/m 3 , 16.6 µg/m 3 , 0.003 mWm 2 and 53.1 dB, respectively. Twenty-two per cent of participants reported to have started using a mobile phone more than 10 years prior to baseline. Repeatability for self-reported exposures was moderate to high (weighted kappa range: 0.69-1) for a subset of participants (n=237) who completed the questionnaire twice. We are actively and passively observing participants; we plan to administer a follow-up questionnaire every 4-5 years-the first follow-up will be completed in 2018-and linkage to cause-of-death and cancer registries occurs on a (bi)annual basis. This prospective cohort offers a unique, large and rich resource for research on contemporary occupational and environmental health risks and will

Cohort profile: LIFEWORK, a prospective cohort study on occupational and environmental risk factors and health in the Netherlands

PubMed Central

Peeters, Petra H; Korevaar, Joke C; Bueno-de-Mesquita, Bas; Verschuren, W M Monique; Verheij, Robert A; Pieterson, Inka; van Leeuwen, Flora E

2018-01-01

Purpose LIFEWORK is a large federated prospective cohort established in the Netherlands to quantify the health effects of occupational and environmental exposures. This cohort is also the Dutch contribution to the international Cohort Study of Mobile Phone Use and Health (COSMOS). In this paper, we describe the study design, ongoing data collection, baseline characteristics of participants and the repeatability of key questionnaire items. Participants 88 466 participants were enrolled in three cohort studies in 2011–2012. Exposure information was collected by a harmonised core questionnaire, or modelled based on occupational and residential histories; domains include air pollution (eg, nitrogen dioxide (NO2), particulate matter with diameter ≤2.5 µm (PM2.5)), noise, electromagnetic fields (EMF), mobile phone use, shift work and occupational chemical exposures. Chronic and subacute health outcomes are assessed by self-report and through linkage with health registries. Findings to date Participants had a median age of 51 years at baseline (range 19–87), and the majority are female (90%), with nurses being over-represented. Median exposure levels of NO2, PM2.5, EMF from base stations and noise at the participants’ home addresses at baseline were 22.9 µg/m3, 16.6 µg/m3, 0.003 mWm2 and 53.1 dB, respectively. Twenty-two per cent of participants reported to have started using a mobile phone more than 10 years prior to baseline. Repeatability for self-reported exposures was moderate to high (weighted kappa range: 0.69–1) for a subset of participants (n=237) who completed the questionnaire twice. Future plans We are actively and passively observing participants; we plan to administer a follow-up questionnaire every 4–5 years—the first follow-up will be completed in 2018—and linkage to cause-of-death and cancer registries occurs on a (bi)annual basis. This prospective cohort offers a unique, large and rich resource for research on contemporary

Early Predictors of ASD in Young Children Using a Nationally Representative Data Set

ERIC Educational Resources Information Center

Jeans, Laurie M.; Santos, Rosa Milagros; Laxman, Daniel J.; McBride, Brent A.; Dyer, W. Justin

2013-01-01

Current clinical diagnosis of Autism Spectrum Disorders (ASD) occurs between 3 and 4 years of age, but increasing evidence indicates that intervention begun earlier may improve outcomes. Using secondary analysis of the Early Childhood Longitudinal Study-Birth Cohort data set, the current study identifies early predictors prior to the diagnosis of…

Concordant integrative gene set enrichment analysis of multiple large-scale two-sample expression data sets.

PubMed

Lai, Yinglei; Zhang, Fanni; Nayak, Tapan K; Modarres, Reza; Lee, Norman H; McCaffrey, Timothy A

2014-01-01

Gene set enrichment analysis (GSEA) is an important approach to the analysis of coordinate expression changes at a pathway level. Although many statistical and computational methods have been proposed for GSEA, the issue of a concordant integrative GSEA of multiple expression data sets has not been well addressed. Among different related data sets collected for the same or similar study purposes, it is important to identify pathways or gene sets with concordant enrichment. We categorize the underlying true states of differential expression into three representative categories: no change, positive change and negative change. Due to data noise, what we observe from experiments may not indicate the underlying truth. Although these categories are not observed in practice, they can be considered in a mixture model framework. Then, we define the mathematical concept of concordant gene set enrichment and calculate its related probability based on a three-component multivariate normal mixture model. The related false discovery rate can be calculated and used to rank different gene sets. We used three published lung cancer microarray gene expression data sets to illustrate our proposed method. One analysis based on the first two data sets was conducted to compare our result with a previous published result based on a GSEA conducted separately for each individual data set. This comparison illustrates the advantage of our proposed concordant integrative gene set enrichment analysis. Then, with a relatively new and larger pathway collection, we used our method to conduct an integrative analysis of the first two data sets and also all three data sets. Both results showed that many gene sets could be identified with low false discovery rates. A consistency between both results was also observed. A further exploration based on the KEGG cancer pathway collection showed that a majority of these pathways could be identified by our proposed method. This study illustrates that we can

Periodontal Disease and Incident Cancer Risk among Postmenopausal Women: Results from the Women's Health Initiative Observational Cohort.

PubMed

Nwizu, Ngozi N; Marshall, James R; Moysich, Kirsten; Genco, Robert J; Hovey, Kathleen M; Mai, Xiaodan; LaMonte, Michael J; Freudenheim, Jo L; Wactawski-Wende, Jean

2017-08-01

Background: Periodontal pathogens have been isolated from precancerous and cancerous lesions and also shown to promote a procarcinogenic microenvironment. Few studies have examined periodontal disease as a risk factor for total cancer, and none have focused on older women. We examined whether periodontal disease is associated with incident cancer among postmenopausal women in the Women's Health Initiative Observational Study. Methods: Our prospective cohort study comprised 65,869 women, ages 54 to 86 years. Periodontal disease information was obtained via self-report questionnaires administered between 1999 and 2003, whereas ascertainment of cancer outcomes occurred through September 2013, with a maximum follow-up period of 15 years. Physician-adjudicated incident total cancers were the main outcomes and site-specific cancers were secondary outcomes. HRs and 95% confidence intervals (CI) were calculated using Cox proportional hazards regression. All analyses were conducted two-sided. Results: During a mean follow-up of 8.32 years, 7,149 cancers were identified. Periodontal disease history was associated with increased total cancer risk (multivariable-adjusted HR, 1.14; 95% CI, 1.08-1.20); findings were similar in analyses limited to 34,097 never-smokers (HR, 1.12; 95% CI, 1.04-1.22). Associations were observed for breast (HR, 1.13; 95% CI, 1.03-1.23), lung (HR, 1.31; 95% CI, 1.14-1.51), esophagus (HR, 3.28; 95% CI, 1.64-6.53), gallbladder (HR, 1.73; 95% CI, 1.01-2.95), and melanoma skin (HR, 1.23; 95% CI, 1.02-1.48) cancers. Stomach cancer was borderline (HR, 1.58; 95% CI, 0.94-2.67). Conclusions: Periodontal disease increases risk of total cancer among older women, irrespective of smoking, and certain anatomic sites appear to be vulnerable. Impact: Our findings support the need for further understanding of the effect of periodontal disease on cancer outcomes. Cancer Epidemiol Biomarkers Prev; 26(8); 1255-65. ©2017 AACR . ©2017 American Association for Cancer

Anterior cervical discectomy and fusion in the outpatient ambulatory surgery setting compared with the inpatient hospital setting: analysis of 1000 consecutive cases.

PubMed

Adamson, Tim; Godil, Saniya S; Mehrlich, Melissa; Mendenhall, Stephen; Asher, Anthony L; McGirt, Matthew J

2016-06-01

OBJECTIVE In an era of escalating health care costs and pressure to improve efficiency and cost of care, ambulatory surgery centers (ASCs) have emerged as lower-cost options for many surgical therapies. Anterior cervical discectomy and fusion (ACDF) is one of the most prevalent spine surgeries performed, and the frequency of its performance is rapidly increasing as the aging population grows. Although ASCs offer significant cost advantages over hospital-based surgical centers, concern over the safety of outpatient ACDF has slowed its adoption. The authors intended to 1) determine the safety of the first 1000 consecutive ACDF surgeries performed in their outpatient ASC, and 2) compare the safety of these outpatient ACDFs with that of consecutive ACDFs performed during the same time period in the hospital setting. METHODS A total of 1000 consecutive patients who underwent ACDF in an ACS (outpatient ACDF) and 484 consecutive patients who underwent ACDF at Vanderbilt University Hospital (inpatient ACDF) from 2006 to 2013 were included in this retrospective study of patients' medical records. Data were collected on patient demographics, comorbidities, operative details, and perioperative and 90-day morbidity. Perioperative morbidity and hospital readmission were compared between the outpatient and inpatient ACDF groups. RESULTS Of the first 1000 outpatient ACDF cases performed in the authors' ASC, 629 (62.9%) were 1-level and 365 (36.5%) were 2-level ACDFs. Mean patient age was 49.5 ± 8.6, and 484 (48.4%) were males. All patients were observed postoperatively at the ASC postanesthesia care unit (PACU) for 4 hours before being discharged home. Eight patients (0.8%) were transferred from the surgery center to the hospital postoperatively (for pain control [n = 3], chest pain and electrocardiogram changes [n = 2], intraoperative CSF leak [n = 1], postoperative hematoma [n = 1], and profound postoperative weakness and surgical reexploration [n = 1]). No perioperative

High colonization rates of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli in Swiss travellers to South Asia- a prospective observational multicentre cohort study looking at epidemiology, microbiology and risk factors.

PubMed

Kuenzli, Esther; Jaeger, Veronika K; Frei, Reno; Neumayr, Andreas; DeCrom, Susan; Haller, Sabine; Blum, Johannes; Widmer, Andreas F; Furrer, Hansjakob; Battegay, Manuel; Endimiani, Andrea; Hatz, Christoph

2014-10-01

International travel contributes to the worldwide spread of multidrug resistant Gram-negative bacteria. Rates of travel-related faecal colonization with extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae vary for different destinations. Especially travellers returning from the Indian subcontinent show high colonization rates. So far, nothing is known about region-specific risk factors for becoming colonized. An observational prospective multicentre cohort study investigated travellers to South Asia. Before and after travelling, rectal swabs were screened for third-generation cephalosporin- and carbapenem-resistant Enterobacteriaceae. Participants completed questionnaires to identify risk factors for becoming colonized. Covariates were assessed univariately, followed by a multivariate regression. Hundred and seventy persons were enrolled, the largest data set on travellers to the Indian subcontinent so far. The acquired colonization rate with ESBL-producing Escherichia coli overall was 69.4% (95% CI 62.1-75.9%), being highest in travellers returning from India (86.8%; 95% CI 78.5-95.0%) and lowest in travellers returning from Sri Lanka (34.7%; 95% CI 22.9-48.7%). Associated risk factors were travel destination, length of stay, visiting friends and relatives, and eating ice cream and pastry. High colonization rates with ESBL-producing Enterobacteriaceae were found in travellers returning from South Asia. Though risk factors were identified, a more common source, i.e. environmental, appears to better explain the high colonization rates.

Longitudinal Surveys of Australian Youth (LSAY) 2009 Cohort: Wave 2 (2010)-- Questionnaire. Technical Report 71A

ERIC Educational Resources Information Center

National Centre for Vocational Education Research (NCVER), 2012

2012-01-01

The Longitudinal Surveys of Australian Youth (LSAY) program studies the progress of several groups of young Australians as they move from school into post-secondary education and work. This technical paper contains the questionnaire for the LSAY 2009 cohort Wave 2 (2010) data set.

Longitudinal Surveys of Australian Youth (LSAY) 2009 Cohort: Wave 3 (2011)--Questionnaire. Technical Report 72A

ERIC Educational Resources Information Center

National Centre for Vocational Education Research (NCVER), 2012

2012-01-01

The Longitudinal Surveys of Australian Youth (LSAY) program studies the progress of several groups of young Australians as they move from school into post-secondary education and work. This technical paper contains the questionnaire for the LSAY 2009 cohort Wave 3 (2011) data set.

Comparison of Estimates between Cohort and Case-Control Studies in Meta-Analyses of Therapeutic Interventions: A Meta-Epidemiological Study.

PubMed

Lanza, Amy; Ravaud, Philippe; Riveros, Carolina; Dechartres, Agnes

2016-01-01

Observational studies are increasingly being used for assessing therapeutic interventions. Case-control studies are generally considered to have greater risk of bias than cohort studies, but we lack evidence of differences in effect estimates between the 2 study types. We aimed to compare estimates between cohort and case-control studies in meta-analyses of observational studies of therapeutic interventions by using a meta-epidemiological study. We used a random sample of meta-analyses of therapeutic interventions published in 2013 that included both cohort and case-control studies assessing a binary outcome. For each meta-analysis, the ratio of estimates (RE) was calculated by comparing the estimate in case-control studies to that in cohort studies. Then, we used random-effects meta-analysis to estimate a combined RE across meta-analyses. An RE < 1 indicated that case-control studies yielded larger estimates than cohort studies. The final analysis included 23 meta-analyses: 138 cohort and 133 case-control studies. Treatment effect estimates did not significantly differ between case-control and cohort studies (combined RE 0.97 [95% CI 0.86-1.09]). Heterogeneity was low, with between-meta-analysis variance τ2 = 0.0049. Estimates did not differ between case-control and prospective or retrospective cohort studies (RE = 1.05 [95% CI 0.96-1.15] and RE = 0.99 [95% CI, 0.83-1.19], respectively). Sensitivity analysis of studies reporting adjusted estimates also revealed no significant difference (RE = 1.03 [95% CI 0.91-1.16]). Heterogeneity was also low for these analyses. We found no significant difference in treatment effect estimates between case-control and cohort studies assessing therapeutic interventions.

Selection bias and patterns of confounding in cohort studies: the case of the NINFEA web-based birth cohort.

PubMed

Pizzi, Costanza; De Stavola, Bianca L; Pearce, Neil; Lazzarato, Fulvio; Ghiotti, Paola; Merletti, Franco; Richiardi, Lorenzo

2012-11-01

Several studies have examined the effects of sample selection on the exposure-outcome association estimates in cohort studies, but the reasons why this selection may induce bias have not been fully explored. To investigate how sample selection of the web-based NINFEA birth cohort may change the confounding patterns present in the source population. The characteristics of the NINFEA participants (n=1105) were compared with those of the wider source population-the Piedmont Birth Registry (PBR)-(n=36 092), and the association of two exposures (parity and educational level) with two outcomes (low birth weight and birth by caesarean section), while controlling for other risk factors, was studied. Specifically the associations among measured risk factors within each dataset were examined and the exposure-outcome estimates compared in terms of relative ORs. The associations of educational level with the other risk factors (alcohol consumption, folic acid intake, maternal age, pregnancy weight gain, previous miscarriages) partly differed between PBR and NINFEA. This was not observed for parity. Overall, the exposure-outcome estimates derived from NINFEA only differed moderately from those obtained in PBR, with relative ORs ranging between 0.74 and 1.03. Sample selection in cohort studies may alter the confounding patterns originally present in the general population. However, this does not necessarily introduce selection bias in the exposure-outcome estimates, as sample selection may reduce some of the residual confounding present in the general population.

Determinants of Low Cloud Properties - An Artificial Neural Network Approach Using Observation Data Sets

NASA Astrophysics Data System (ADS)

Andersen, Hendrik; Cermak, Jan

2015-04-01

This contribution studies the determinants of low cloud properties based on the application of various global observation data sets in machine learning algorithms. Clouds play a crucial role in the climate system as their radiative properties and precipitation patterns significantly impact the Earth's energy balance. Cloud properties are determined by environmental conditions, as cloud formation requires the availability of water vapour ("precipitable water") and condensation nuclei in sufficiently saturated conditions. A main challenge in the research of aerosol-cloud interactions is the separation of aerosol effects from meteorological influence. To gain understanding of the processes that govern low cloud properties in order to increase accuracy of climate models and predictions of future changes in the climate system is thus of great importance. In this study, artificial neural networks are used to relate a selection of predictors (meteorological parameters, aerosol loading) to a set of predictands (cloud microphysical and optical properties). As meteorological parameters, wind direction and velocity, sea level pressure, static stability of the lower troposphere, atmospheric water vapour and temperature at the surface are used (re-analysis data by the European Centre for Medium-Range Weather Forecasts). In addition to meteorological conditions, aerosol loading is used as a predictor of cloud properties (MODIS collection 6 aerosol optical depth). The statistical model reveals significant relationships between predictors and predictands and is able to represent the aerosol-cloud-meteorology system better than frequently used bivariate relationships. The most important predictors can be identified by the additional error when excluding one predictor at a time. The sensitivity of each predictand to each of the predictors is analyzed.

Age-period-cohort analysis of suicides among Japanese 1950-2003: a Bayesian cohort model analysis.

PubMed

Ooe, Yosuke; Ohno, Yuko; Nakamura, Takashi

2009-07-01

The suicide rate in Japan is one of the highest in the world and presents us with a considerable challenge. Demographic statistics show that the number of suicides is on the rise, and at roughly 30,000 people per year have committed suicide since 1998. Suicide trends are not only related to economic boom and bust but also to certain generations and age groups. During the 1950s, there was a remarkably high suicide rate among people in their 20s, and this cohort was identical to that of the middle-age generation in the 1980s. It is important to separately understand both the trend of suicide rates and the numbers analyzed to determine the different factors that influence suicide. These include age, time period, cohort, interaction between age and time period, and changes in population composition. We performed an age-period-cohort analysis of annual trends of suicide rates by age group in Japan using a Bayesian cohort model. With the help of the Nakamura method, we have been able to break down the effects of age, time period, cohort, and the age-by-period interaction. The cohort comprised of people born in the 1930s demonstrated a relatively high suicide rate. Men currently in their 50s also belong to a high suicide rate cohort. Regarding the period effect, business cycles and by-period interaction effect, it became apparent that the high suicide rate among young adults in their early 20s around 1960 was slowing, especially among men. Instead, there was an obvious recent trend for men in their late 50s to have the highest suicide rate. This study confirmed that age-period-cohort analysis can describe these trends of suicide mortality of the Japanese.

The real-world effectiveness and safety of fingolimod in relapsing-remitting multiple sclerosis patients: An observational study

PubMed Central

Damas, Fátima; Páramo, Maria Dolores; Ruiz-Peña, Juan Luis; Navarro, Guillermo

2017-01-01

Fingolimod approval was based mainly on two clinical trials, FREEDOMS and TRANSFORMS, which demonstrated the efficacy and safety of fingolimod in patients with multiple sclerosis (MS). We present an observational study that validates these trials findings in a real-world setting, whereby the effectiveness and safety of fingolimod was assessed in Seville’s’ (Spain) clinical practice. This retrospective study in MS patients assessed effectiveness (relapses, EDSS, gadolinium-enhancing T1 and new/enlarged T2-weighted lesions): total cohort (n = 249) and stratified according to prior treatment (glatiramer acetate/interferon beta-1 [immunomodulator], natalizumab, naïve), gender, basal EDSS score, basal Gd+ lesions, ARR prior to treatment, age at treatment initiation and number of prior treatments. A multivariante model was used to assess the ARR with baseline characteristics. The safety profile (adverse events [AEs]) was also described. Fingolimod reduced the annualized relapse rate (ARR) by 75%, 67% and 85% in the total cohort, patients previously treated with immunomodulatory and naïve patients (p<0.0001 all cases). However, patients previously treated with natalizumab kept a constant ARR. The ARR results and the consequent increase in the proportion of relapse-free patients were independent of the age at treatment initiation, number of prior treatments, gender and basal Gd+ lesions. Although fingolimod was effective regardless the basal EDSS score and ARR prior to fingolimod treatment, better outcomes were observed in patients with basal EDSS score <3 (0.2 vs. 0.4; p = 0.0244) and ARR ≥ 2 prior to fingolimod treatment (p = 0.0338). Only the basal EDSS score was association with ARR in the first 24 months of fingolimod treatment in the multivariante model (p = 0.0439). The cumulative probability of disability progression was 20% (month-24) in the total cohort, and was independent from prior treatment, age at treatment initiation, number of prior treatments

Age, time period, and birth cohort differences in self-esteem: Reexamining a cohort-sequential longitudinal study.

PubMed

Twenge, Jean M; Carter, Nathan T; Campbell, W Keith

2017-05-01

Orth, Trzesniewski, and Robins (2010) concluded that the nationally representative Americans' Changing Lives (ACL) cohort-sequential study demonstrated moderate to large age differences in self-esteem, and no birth cohort (generational) differences in the age trajectory. In a reanalysis of these data using 2 different statistical techniques, we find significant increases in self-esteem that could be attributed to birth cohort or time period. First, hierarchical linear modeling analyses with birth cohort as a continuous variable (vs. the multiple group formulation used by Orth et al.) find that birth cohort has a measurable influence on self-esteem through its interaction with age. Participants born in later years (e.g., 1960) were higher in self-esteem and were more likely to increase in self-esteem as they aged than participants born in earlier years (e.g., 1920). However, the estimated age trajectory up to age 60 is similar in Orth et al.'s results and in the results from our analyses including cohort. Second, comparing ACL respondents of the same age in 1986 versus 2002 (a time-lag design) yields significant birth cohort differences in self-esteem, with 2002 participants of the same age higher in self-esteem than those in 1986. Combined with some previous studies finding significant increases in self-esteem and positive self-views over time, these results suggest that cultural change in the form of cohort and time period cannot be ignored as influences in cross-sectional and longitudinal studies. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Cohort Profile: Recruitment cohorts in the neuropsychological substudy of the Multicenter AIDS Cohort Study.

PubMed

Becker, James T; Kingsley, Lawrence A; Molsberry, Samantha; Reynolds, Sandra; Aronow, Aaron; Levine, Andrew J; Martin, Eileen; Miller, Eric N; Munro, Cynthia A; Ragin, Ann; Sacktor, Ned; Selnes, Ola A

2015-10-01

The Multicenter AIDS Cohort Study (MACS) is one of the largest and longest running studies of the natural and treated history of HIV disease. The Neuropsychological (NP) substudy was begun in 1988 following reports of significant adverse neurological consequences of HIV disease, including dementia. The goal was to characterize the neuropsychological deficits among individuals with HIV disease, and track the natural history of the neurological complications over time. There were three distinct MACS recruitment stages that focused on different groups of HIV-infected men, or men at risk for infection. Initially, a subcohort was evaluated semi-annually with NP tests but, beginning in 2005, the entire group of MACS participants have had NP examinations biannually, unless closer follow-up was warranted. The participants complete a battery of NP tests, and are classified as either normal, mildly or severely impaired using the Antinori criteria for HIV-Associated Neurocognitive Disorder (HAND). Additional behavioural data, including mood state and psychoactive substance use, are recorded as part of the main MACS data collection. The MACS public data set (PDS) has been available since 1994 and includes baseline and 6-monthly follow-up data. Beginning in October 1995, the PDS has been released annually with new releases superseding previous versions. © The Author 2014; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.

Design and implementation of the canadian kidney disease cohort study (CKDCS): A prospective observational study of incident hemodialysis patients

PubMed Central

2011-01-01

Background Many nephrology observational studies use renal registries, which have well known limitations. The Canadian Kidney Disease Cohort Study (CKDCS) is a large prospective observational study of patients commencing hemodialysis in five Canadian centers. This study focuses on delineating potentially reversible determinants of adverse outcomes that occur in patients receiving dialysis for end-stage renal disease (ESRD). Methods/Design The CKDCS collects information on risk factors and outcomes, and stores specimens (blood, dialysate, hair and fingernails) at baseline and in long-term follow-up. Such specimens will permit measurements of biochemical markers, proteomic and genetic parameters (proteins and DNA) not measured in routine care. To avoid selection bias, all consenting incident hemodialysis patients at participating centers are enrolled, the large sample size (target of 1500 patients), large number of exposures, and high event rates will permit the exploration of multiple potential research questions. Preliminary Results Data on the baseline characteristics from the first 1074 subjects showed that the average age of patients was 62 (range; 50-73) years. The leading cause of ESRD was diabetic nephropathy (41.9%), and the majority of the patients were white (80.0%). Only 18.7% of the subjects received dialysis in a satellite unit, and over 80% lived within a 50 km radius of the nearest nephrologist's practice. Discussion The prospective design, detailed clinical information, and stored biological specimens provide a wealth of information with potential to greatly enhance our understanding of risk factors for adverse outcomes in dialysis patients. The scientific value of the stored patient tissue will grow as new genetic and biochemical markers are discovered in the future. PMID:21324196

Differences in rates of switchbacks after switching from branded to authorized generic and branded to generic drug products: cohort study

PubMed Central

Sarpatwari, Ameet; Dejene, Sara; Khan, Nazleen F; Lii, Joyce; Rogers, James R; Dutcher, Sarah K; Raofi, Saeid; Bohn, Justin; Connolly, John; Fischer, Michael A; Kesselheim, Aaron S; Gagne, Joshua J

2018-01-01

Abstract Objectives To compare rates of switchbacks to branded drug products for patients switched from branded to authorized generic drug products, which have the same active ingredients, appearance, and excipients as the branded product, with patients switched from branded to generic drug products, which have the same active ingredients as the branded product but may differ in appearance and excipients. Design Observational cohort study. Setting Private (a large commercial health plan) and public (Medicaid) insurance programs in the US. Participants Beneficiaries of a large US commercial health insurer between 2004 and 2013 (primary cohort) and Medicaid beneficiaries between 2000 and 2010 (replication cohort). Main outcome measures Patients taking branded products for one of the study drugs (alendronate tablets, amlodipine tablets, amlodipine-benazepril capsules, calcitonin salmon nasal spray, escitalopram tablets, glipizide extended release tablets, quinapril tablets, and sertraline tablets) were identified when they switched to an authorized generic or a generic drug product after the date of market entry of generic drug products. These patients were followed for switchbacks to the branded drug product in the year after their switch to an authorized generic or a generic drug product. Cox proportional hazard models were used to estimate hazard ratios and 95% confidence intervals after adjusting for demographics, including age, sex, and calendar year. Inverse variance meta-analysis was used to pool adjusted hazard ratios across all drug products. Results A total of 94 909 patients switched from branded to authorized generic drug products and 116 017 patients switched from branded to generic drug products and contributed to the switchback analysis. Unadjusted incidence rates of switchback varied across drug products, ranging from a low of 3.8 per 100 person years (for alendronate tablets) to a high of 17.8 per 100 person years (for amlodipine

Efficient Bayesian mixed model analysis increases association power in large cohorts

PubMed Central

Loh, Po-Ru; Tucker, George; Bulik-Sullivan, Brendan K; Vilhjálmsson, Bjarni J; Finucane, Hilary K; Salem, Rany M; Chasman, Daniel I; Ridker, Paul M; Neale, Benjamin M; Berger, Bonnie; Patterson, Nick; Price, Alkes L

2014-01-01

Linear mixed models are a powerful statistical tool for identifying genetic associations and avoiding confounding. However, existing methods are computationally intractable in large cohorts, and may not optimize power. All existing methods require time cost O(MN2) (where N = #samples and M = #SNPs) and implicitly assume an infinitesimal genetic architecture in which effect sizes are normally distributed, which can limit power. Here, we present a far more efficient mixed model association method, BOLT-LMM, which requires only a small number of O(MN)-time iterations and increases power by modeling more realistic, non-infinitesimal genetic architectures via a Bayesian mixture prior on marker effect sizes. We applied BOLT-LMM to nine quantitative traits in 23,294 samples from the Women’s Genome Health Study (WGHS) and observed significant increases in power, consistent with simulations. Theory and simulations show that the boost in power increases with cohort size, making BOLT-LMM appealing for GWAS in large cohorts. PMID:25642633

Socioeconomic Position, Health, and Possible Explanations: A Tale of Two Cohorts

PubMed Central

Fuhrer, R.; Shipley, M. J.; Chastang, J. F.; Schmaus, A.; Niedhammer, I.; Stansfeld, S. A.; Goldberg, M.; Marmot, M. G.

2002-01-01

Objectives. We examined whether the social gradient for measures of morbidity is comparable in English and French public employees and investigated risk factors that may explain this gradient. Methods. This longitudinal study of 2 occupational cohorts—5825 London civil servants and 6818 French office-based employees—used 2 health outcomes: long spells of sickness absence during a 4-year follow-up and self-reported health. Results. Strong social gradients in health were observed in both cohorts. Health behaviors showed different relations with socioeconomic position in the 2 samples. Psychosocial work characteristics showed strong gradients in both cohorts. Cohort-specific significant risk factors explained between 12% and 56% of the gradient in sickness absence and self-reported health. Conclusions. Our cross-cultural comparison suggests that some common susceptibility may underlie the social gradient in health and disease, which explains why inequalities occur in cultures with different patterns of morbidity and mortality. PMID:12144986

[Mortality of psychiatric patients. A retrospective cohort study of in-patients at the Psychiatric Hospital of Reggio Emilia].

PubMed

Ballone, E; Contini, G

1992-03-01

The authors report the results of historical cohort study in long-term patients of psychiatric hospitals in Reggio Emilia. The cohort was formed by 790 patients hospitalized before 1978, and has been followed-up until 31/12/'89. The results of the study are: 269 subjects deceased (34%); 117 discharges (14.8%) and 411 (52.1%) still in hospital on 1/1/'90. An excess mortality was observed in the cohort. Mortality appears to be particularly high among young patient and females.

Estimating the Cost of Neurosurgical Procedures in a Low-Income Setting: An Observational Economic Analysis.

PubMed

Abdelgadir, Jihad; Tran, Tu; Muhindo, Alex; Obiga, Doomwin; Mukasa, John; Ssenyonjo, Hussein; Muhumza, Michael; Kiryabwire, Joel; Haglund, Michael M; Sloan, Frank A

2017-05-01

There are no data on cost of neurosurgery in low-income and middle-income countries. The objective of this study was to estimate the cost of neurosurgical procedures in a low-resource setting to better inform resource allocation and health sector planning. In this observational economic analysis, microcosting was used to estimate the direct and indirect costs of neurosurgical procedures at Mulago National Referral Hospital (Kampala, Uganda). During the study period, October 2014 to September 2015, 1440 charts were reviewed. Of these patients, 434 had surgery, whereas the other 1006 were treated nonsurgically. Thirteen types of procedures were performed at the hospital. The estimated mean cost of a neurosurgical procedure was $542.14 (standard deviation [SD], $253.62). The mean cost of different procedures ranged from $291 (SD, $101) for burr hole evacuations to $1,221 (SD, $473) for excision of brain tumors. For most surgeries, overhead costs represented the largest proportion of the total cost (29%-41%). This is the first study using primary data to determine the cost of neurosurgery in a low-resource setting. Operating theater capacity is likely the binding constraint on operative volume, and thus, investing in operating theaters should achieve a higher level of efficiency. Findings from this study could be used by stakeholders and policy makers for resource allocation and to perform economic analyses to establish the value of neurosurgery in achieving global health goals. Copyright © 2017 Elsevier Inc. All rights reserved.

Impact of Pre-Pregnancy BMI on B Vitamin and Inflammatory Status in Early Pregnancy: An Observational Cohort Study