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Estimating the precision of a single proportion via a 100(1-α)% confidence interval in the presence of clustered data is an important statistical problem. It is necessary to account for possible over-dispersion, for instance, in animal-based teratology studies with within-litter correlation, epidemiological studies that involve clustered sampling, and clinical trial designs with multiple measurements per subject. Several asymptotic confidence interval methods have been developed, which have been found to have inadequate coverage of the true proportion for small-to-moderate sample sizes. In addition, many of the best-performing of these intervals have not been directly compared with regard to the operational characteristics of coverage probability and empirical length. This study uses Monte Carlo simulations to calculate coverage probabilities and empirical lengths of five existing confidence intervals for clustered data across various true correlations, true probabilities of interest, and sample sizes. In addition, we introduce a new score-based confidence interval method, which we find to have better coverage than existing intervals for small sample sizes under a wide range of scenarios. [ABSTRACT FROM AUTHOR]

Objective: To investigate whether drinking thin liquids with safety strategies increases the risk for pneumonia as compared with thickened liquids in patients who have demonstrated aspiration of thin liquids. Data sources: Seven electronic databases, one clinical register, and three conference archives were searched. No language or publication date restrictions were imposed. Reference lists were scanned and authors and experts in the field were contacted. Review methods: A blind review was performed by two reviewers for published or unpublished randomized controlled trials and prospective non-randomized trials comparing the incidence of pneumonia with intake of thin liquids plus safety strategies vs. thickened liquids in adult patients who aspirated on thin liquids. The data were extracted from included studies. Odds ratios (OR) for pneumonia were calculated from the extracted data. Risk of bias was also assessed with the included published trials. Results: Seven studies out of 2465 studies including 650 patients met the inclusion criteria. All of the seven studies excluded patients with more than one known risk factor for pneumonia. Six studies compared thin water protocols to thickened liquids for pneumonia prevention. A meta-analysis was done on the six studies, showing no significant difference for pneumonia risk (OR = 0.82; 95% CI = 0.05–13.42; p = 0.89). Conclusions: There was no significant difference in the risk of pneumonia in aspirating patients who took thin liquids with safety strategies compared with those who took thickened liquids only. This result, however, is generalizable only for patients with low risk of pneumonia. [ABSTRACT FROM AUTHOR]

Objective: The objective of this study is to identify features of the environment associated with community participation of older adults. Method: A systematic review of studies that examined associations between environment and community participation in older adults was conducted. Environmental features were extracted and grouped using the International Classification of Functioning, Disability, and Health’s environmental categories. Meta-analysis of environmental categories was conducted by calculating combined effect size (ES) estimates. Results: Significant, small to moderate, random ESs were found for six of seven environmental categories: neighborliness (ES = 0.52, 95% confidence interval [CI] = [0.18, 0.87]), social support (ES = 0.38, 95% CI = [0.13, 0.62]), land-use diversity (ES = 0.29, 95% CI = [0.16, 0.42]), transportation (ES = 0.29, 95% CI = [0.15, 0.43]), civil protection (e.g., safety; ES = 0.27, 95% CI = [0.0, 0.54]), and street connectivity/walkability (ES = 0.20, 95% CI = [0.15, 0.26]). Discussion: Community initiatives that address specific features of the social environment and street-level environment may increase community participation of older adults. [ABSTRACT FROM AUTHOR]

Job retention services are recommended for people with chronic diseases based on their high risk for work disability. This randomized trial tested the effectiveness of a job retention intervention in a sample of employed persons with rheumatic diseases at risk for work disability. One hundred and twenty-two experimental participants received the job retention intervention, and 120 controls received written materials. Employment status was assessed at 6-month intervals up to 48 months after enrollment. Main outcomes were time to job loss and satisfaction with the experimental and control interventions. The log-rank test was used to detect a difference between the groups in time to job loss. Between-group differences in satisfaction scores were analyzed using Wilcoxon tests. Job loss was delayed in experimental participants compared with controls, p = 0.03. Satisfaction scores for the job retention intervention were substantially higher than those for the written materials, p < 0.0001. Job retention intervention has the potential to reduce the high rates of chronic disease--associated job loss. [ABSTRACT FROM AUTHOR]

Many people with arthritis become work disabled, but little is known about (a) the types of work barriers they experience and (b) their use of job accommodations. Our objectives were to describe work barriers and use of accommodations and to examine factors associated with accommodation use in persons with arthritis at risk for work disability. Barrier assessment was conducted using the Work Experience Survey. Factors associated with accommodation use were analyzed by logistic regression. The overwhelming majority of the 121 participants (98%) reported having one or more barriers, and 68% reported 10 or more barriers; 38% used an accommodation. Greater functional limitations and self-efficacy for accommodation request were each associated with accommodation use. Even though these employed persons with arthritis faced multiple barriers at work, only a small number used any form of job accommodation. [ABSTRACT FROM AUTHOR]

Use of statistical methods for early stopping of clinical trials allows more efficient and ethical utilization of subjects. In uncommon diseases, where the pool of potential subjects is limited, these methods provide a way to maximize the information gathered from trials. For trials in lupus, methods for early stopping should be more widely utilized. We discuss the ethics, practical aspects, pros and cons, and statistical foundations of some established methods for early stopping, with an emphasis on those that have available implementation in computer software. An example of the design and analysis of a treatment trial in systemic lupus erythematosus with the triangular test method of early stopping is also given. [ABSTRACT FROM AUTHOR]