Tracking substance abusers in longitudinal research: understanding follow-up contact difficulty.
Studies examining follow-up contact difficulty provide useful information for planning longitudinal studies and for assessing the validity of follow-up data. Contact difficulty was examined among 96 substance abusers following substance abuse treatment. Interview completion rates at the 3-month and 6-month follow-ups were 93 and 97%, respectively. The extent of contact efforts required to complete follow-up interviews varied substantially but tended to be greater at the 3-month follow-up than at the 6-month follow-up. Contact difficulty was related to reuse of substances at the 3-month and at the 6-month follow-ups with reusers requiring greater contact efforts than abstainers. None of the baseline individual and contextual variables examined significantly predicted level of contact effort at follow-ups. Attrition-related validity implications are discussed along with practical suggestions for planning tracking efforts.
University of Michigan, Alcohol Research Center, Ann Arbor 48108, USA.
M A
MA
Walton
C S
CS
Ramanathan
T M
TM
Reischl
D000328:Adult; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007406:Interview, Psychological; D008137:Longitudinal Studies; D008297:Male; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D019966:Substance-Related Disorders / Q000175:diagnosis* / Q000628:therapy; D016896:Treatment Outcome