Site differences in treatment outcomes are not often highlighted when the results of multisite randomized clinical trials (MRCTs) are reported. The primary analyses of a 6-site MRCT, the Treatment of SSRI-Resistant Depression in Adolescents (TORDIA) study, showed substantial variation by site in the performance of a medication-only condition and a…

Analyzes the attrition dilemma and reviews the methods used to compensate for data loss. Argues that attrition is not utlimately a problem of bias but a problem of lack of information. Offers a reformulation that integrates single-case studies with traditional group comparison methodology in an attempt to find optimal causal relations of…

Interventions for a variety of emotional and behavioral problems are commonly delivered in the context of treatment groups, with many using rolling admission to sustain membership (i.e., admission, dropout, and discharge from group are perpetual and ongoing). The authors present an overview of the analytic challenges inherent in rolling group data…

Examined seven-year adolescent panel to determine whether attrition effects varied by type of substance assessed and method of measurement. Found study dropouts were more likely to use substances and reported higher mean use of substances at baseline than stayers; attrition effects varied by substance; and mean use comparisons were more likely to…

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…

Investigated the feasibility of a behavioral weight-loss program at the worksite. Three groups of participants (N=133) completed a behavioral treatment program. Two groups also received a structured-maintenance program. Although attrition rates were high, the three groups lost a significant amount of weight. The structured training group…

Examined factors associated with research attrition in a long-term follow-up study (48 months). Researchers attempted to contact all randomized participants, not just those who completed treatment. The analyses deal primarily with refusal, the main reason for attrition. Short-term outcome did not predict refusal. The findings, if generalizable,…

Reviews epidemiological studies of cardiovascular diseases especially coronary heart disease (CHD), to document their major public health importance, changes in mortality during this century, and international comparisons of trends. Finds major risk factors for CHD are determined in large part by psychosocial and behavioral mechanisms. Asserts…