A group-administered timeline followback assessment of alcohol use

Objective: The current study compares retrospective self-reports of quantity and frequency of drinking with the Timeline Followback (TLFB) method administered in groups or to individuals to determine the equivalence of these methods. Method: Two hundred and eleven male college students who reported drinking at least two times per week participated; 118 completed the TLFB in a group setting, and 93 completed it individually. Drinking variables assessed were drinking days, average drinks and total drinks during a 30-day period. Results: Pearson's correlation coefficients revealed significant correlations between single-item quantity and frequency measures and the TLFB on all three variables for the two administration styles. Furthermore, the group TLFB yielded similar correlations to self-reports as the individual TLFB on drinking days and average drinks. However, the correlation between total drinks on the TLFB and the individual item report of drinking days was higher for individual administration than in the group administration. Conclusions: This study suggests that the group TLFB yields an accurate portrayal of students' quantity, but not frequency, of use. In addition, the group-administered TLFB has the potential to parallel individual interviews and serve as an efficient means of collecting information, but further studies with modified research designs are necessary to validate this alternate method of TLFB administration.