Innovative retention methods in longitudinal research: A case study of the Developmental Trends Study

Minimizing participant attrition is vital to the success of longitudinal research. The Developmental Trends Study (DTS), a longitudinal study of the development of dis-ruptive behavior disorders, has achieved a low attrition rate throughout the study. The development of early retention strategies, managing contact and scheduling history through the use of electronic databases, interviewer persistence, and the emergence of new electronic search methods have contributed to the success of our study. A literature review of retention methodology and practical solutions to maintain participant cooperation is described. A case study of the DTS is presented to inform researchers in longitudinal research on new methods used to maintain high retention rates. KEY WORDS: attrition; subject retention; search methods; difficult subjects; longitudinal research. Increasing emphasis has been placed on the study of developmental influ-ences, and on fluctuations over time in outcomes of interest. In longitudinal survey research, maintaining subject participation over time is essential to prevent se-lective attrition, and to allow studies to address their long-term aims. Significant attrition can erode demonstrable intervention effects by diminishing exposure o