The objective of this meta-epidemiological study was to explore the impact of attrition rates on treatment effect estimates in randomised trials of chronic inflammatory diseases (CID) treated with biological and targeted synthetic disease-modifying drugs. We sampled trials from Cochrane reviews. Attrition rates and primary endpoint results were…

Morphological awareness has been assessed longitudinally for monolinguals and bilinguals to trace the developmental trend. Researchers have found the important role it plays in literacy development including vocabulary growth and reading development. Conclusions about the important role morphological awareness play in literacy development are…

Inherent in applied developmental sciences is the threat to validity and generalizability due to missing data as a result of participant drop-out. The current paper provides an overview of how attrition should be reported, which tests can examine the potential of bias due to attrition (e.g., t-tests, logistic regression, Little's MCAR test,…

This study aims to explore the current published research on Language Massive Open Online Courses (LMOOCs), outlining the types of papers, countries where studies were performed and institutions devoted to this field. Also, it intends to classify the reviewed literature following a general categorisation of MOOCs, and to identify the main trends…

This paper comprehensively reviews the published literature investigating health-related quality of life (HRQOL) following general traumatic injury in individuals between birth and 18 years. Studies were not considered if they primarily compared medical treatment options, evaluated physical function but not other aspects of HRQOL, or focused on…

Discusses the methods used to maximize retention in a longitudinal study of adolescent drinking. Strategies to minimize attrition included the collection of detailed contact information, incentives for participation, postcard and telephone reminders and telephone interviews. Ninety-six percent of the original sample completed the first follow-up…

Briefly outlines problems associated with definition and official certification of suicide and reviews literature pertaining to validity and reliability of suicide statistics. Considers process of suicide certification as a test, estimating its sensitivity, specificity, and predictive value, using data from studies reviewed. (NB)

Presents a summary of an earlier monograph on the recruitment and retention of older ethnic minority individuals. Findings suggest that recruitment and retention success occurs when there is a match between the goals of the ethnic minority communities and the research community. (Contains 10 references and 3 tables.) (GCP)

This introduction to a special issue describes children's injuries in statistical, historical, and social terms. The following key concepts are presented: (1) Childhood injuries are neither random, unavoidable, nor inexplicable; (2) various disciplines suggest different interventions; (3) individuals or populations may be targeted for prevention…

This article discusses the limitations of 14 randomized controlled trials of exercise rehabilitation for patients who sustained myocardial infarction. The difficulty of sampling patients and controlling the sample size is discussed and the benefits of pooled statistical evidence are considered. (JL)

Describes common methodological inadequacies in research on treatment of obesity and suggests alternatives. Importance of multiple measurement of outcome is emphasized. Merits of alternative single-subject and between-groups experimental designs are discussed. Reasons for conspicuous lack of long-term follow-ups are analyzed. Recommendations for…

Presents procedures for reducing attrition in clinical research and provides a case study for examination by researchers. Includes lists of preventative strategies and statistical methodologies to reduce attrition and bias. Argues that early planning for attrition by adjusting sample sizes is a scientifically sound approach to clinical research…

Reviews the problems associated with recruiting older minorities into mental health research studies and proposes a consumer-centered model of research methodology that addresses the barriers to recruitment and retention in this population. Results reveal that although the consumer-centered methods result in better recruitment of older minorities…

Examines the problem of attrition from therapeutic treatment programs, discussing the scope and limitations of research about the causes of subject attrition. Examines the applicability of proposed methodological remedies for assessing and countering attrition. Such research often suffers from inadequate conceptualization and weak design. (SLD)

Reviews attrition rates in bereavement research and demonstrates prevalence of low acceptance rates and lack of knowledge about bias due to self-selection. Reports results of empirical study which showed effect of depression on willingness to participate: widowers who were less depressed agreed to participate; widows who were more depressed were…