DETERMINANTS OF LIFE-COURSE VARIATION IN THE FREQUENCY OF ALCOHOL-CONSUMPTION - METAANALYSIS OF STUDIES FROM THE COLLABORATIVE ALCOHOL-RELATED LONGITUDINAL PROJECT

Objective: This report evaluates the relative contribution of predicto rs of change in the frequency of alcohol consumption among drinkers, b ased on the quantitative synthesis of data from 27 longitudinal studie s of the general population. The analysis has two objectives: (1) to e valuate the impact of selected demographic characteristics on the magn itude and trajectory of change in drinking across multiple samples, an d (2) to assess the influence of methodological characteristics on the consistency of results across studies. Method: Raw data from studies including two serial measures of the frequency of alcohol consumption are analyzed. Fixed, random and mixed effects models for meta-analysis are used to pool measures across observations and model the influence of predictors on variability between results. Results: Gender-based v ariation in the patterning of change is present across all observation s, but concentrated in early periods of the life course. Age displays significant predictive effects across all observations, but statistica lly uniform results are obtained for subjects aged 30 and over. The na tional origin of study predicts larger amounts of variation than do ot her demographic predictors in the models. Significant effects are obse rved for several methodological characteristics of studies. Variation among effect estimates is associated with differences between samples in the interval between first and final measurements, the date of firs t measurement (a proxy for the historical context of the sample), the percentage retention of subjects between measurements and the time fra me of the original alcohol measure. Conclusions: Based on the synthesi s of data from multiple longitudinal samples, this study (1) character izes normative developmental patterning in the frequency of alcohol co nsumption and demonstrates the varying effects of demographic factors across the life-course; (2) indicates the key influence of cultural an d historical context on the establishment of drinking patterns; and (3 ) confirms the impact of methodological differences on variation in th e results of studies.