The readiness to change questionnaire in subjects with hazardous alcohol consumption, alcohol misuse and dependence in a general population survey.

AIMS: To investigate properties and aspects of validity of the Readiness to Change Questionnaire (RCQ) when applied to hazardous drinking, alcohol-abusing or alcohol-dependent subjects sampled from the general population.
METHODS: In a representative survey conducted in the general population of a region in northern Germany, participants were randomly selected from resident registration office files, contacted and interviewed personally (n = 4.075). A total of 302 subjects who showed hazardous drinking behaviour (n = 202) or met diagnostic criteria of alcohol misuse (n = 46) or alcohol dependence (n = 54) were assessed and diagnosed using the Munich Composite International Diagnostic Interview (M-CIDI) according to DSM-IV diagnostic criteria. The battery of self-report questionnaires comprised, among others, the RCQ, and two methods of allocation were used, the quick method and the refined method of allocation. According to the method of allocation used, the stages are: precontemplation (PC), contemplation (C), preparation (P) and action (A); P may only be assigned using the refined method.
RESULTS: The RCQ, a brief instrument to assess stages of change in individuals sampled from the general population, gave internal consistencies of: PC = 0.68, C = 0.79, A = 0.83. Allocation to stages of change according to the quick method resulted in 67% of subjects being allocated to PC, 24% to C and 8% to A and according to the refined method in 58% to PC, 15% to C, 4% to P, 4% to A, with 19% not being classified because of non-theory-consistent scale profiles.
CONCLUSIONS: Classification did not differ substantially according to the method of allocation. A three-factor solution, as reported in the literature, could not be replicated. Allocation to stages of change with the RCQ reflected predictions made from the Transtheoretical Model of behaviour change.