Comparing the predictive validity of the four-factor and five-factor (bifactor) measurement structures of the drinking motives questionnaire.

Introduction: The Drinking Motives Questionnaire (DMQ-R) is the most widely administered instrument to assess reasons for consuming alcohol and is conventionally premised on a four-factor structure. Recent research instead reveals that a bifactor measurement model of five motive factors (one general and four specific) represents a superior psychometric embodiment of the scale. The current study evaluated and compared the predictive validity of the four-factor and five-factor models of drinking motives in longitudinally explaining alcohol use and problems.

Methods: Adult participants (N=413; age range=18-79 years) completed measures of drinking motives (Time 1) and alcohol use and problems one month later (Time 2).

Results: Confirmatory factor analyses corroborated the four-factor (social, enhancement, conformity, and coping motives) and five-factor (each item double loading on general motives and a specific motives factor) measurement structures, but the latter rendered stronger fit indices. Structural equation models revealed that lower social motives, higher enhancement motives, and higher coping motives prospectively contributed to alcohol use. Furthermore, lower social motives, higher conformity motives, higher coping motives, and greater alcohol use contributed to alcohol problems.

Discussion: The same set of paths emerged as significantly predictive in both models, but general motives additionally explained alcohol use and problems in the five-factor model. The incremental contribution of general motives (beyond the specific motives) on alcohol intake and detrimental consequences supports the predictive validity of the drinking reasons paradigm embodied by the inclusion of a global factor.