LAUSR

BACKGROUND Participant retention is a major challenge in clinical research, especially in studies with multiple, longitudinal research assessments Despite the importance of retention methods, there is little empirical research on how cohort retention efforts are perceived by study participants. RESEARCH QUESTION To evaluate the association between the number of attempts undertaken to contact participants for research assessments in a longitudinal cohort study and participants' feeling of being bothered regarding such contact attempts. STUDY DESIGN AND METHODS Secondary analysis of 315 Acute Respiratory Disorder Syndrome (ARDS) survivors participating in a prospective study using comprehensive strategies for participant follow-up at 6 and 12 months that achieved >95% participant retention. After completing a 242-question research assessment lasting 20 to 40-minutes, participants were surveyed for feedback. RESULTS At 6 and 12 months, only 5% and 8% of participants, respectively, reported being bothered "more than a little bit" by the study contact attempts, with an Odds Ratio (95% confidence interval) of 1.06 (1.02 - 1.10) for each contact attempt. Participants' mental health symptoms at follow-up assessment were not associated with reports of being bothered INTERPRETATION: Comprehensive cohort retention efforts can achieve >95% retention rates in a national longitudinal study, with the vast majority of participants reporting little or no bother by contact attempts. Despite a high frequency of mental health symptoms in this population, such symptoms were not associated with participant feedback regarding contact attempts. Careful training of research staff may be important in achieving such results.