Applying a modified Prochaska's model of readiness to change for general practitioners on depressive disorders in CME programmes: validation of tool

Objective To assess the validity and reliability of an 11-item questionnaire for stages of readiness to change according to a modified Prochaska model (including attitude, intention and action stage) in the context of continuing medical education (CME) on depressive disorders for general practitioners (GPs) in Tehran, Iran. Methods Three hundred and fifty GPs were recruited for filling in a questionnaire in order to assess content validity and modifying the questionnaire. Fifty-nine GPs were involved for testing reliability and 39 GPs for testing concurrent validity. Content validity of the questionnaire was assessed by expert consensus. Concurrent validity was assessed by correlating the results of a semi-structured interview with those of the self-assessment questionnaire. For testing reliability there was a test-retest approach with an interval of 3-7 days. Results A panel of experts was held at four times and the final version of modified Prochaska questionnaire (MPQ) was compiled by the panel. Total kappa coefficient for concurrent validity of the whole questionnaire was 0.80. Only two of the questions had a kappa coefficient lower than 0.70. In the test-retest, 96% of participants reassigned to the same stage and the total kappa coefficient of reliability was 0.89 for the whole questionnaire. Conclusion The validity and reliability of the MPQ for assessing GPs' readiness to change in the field of depressive disorders were found to be high in the Iranian context. These findings support its application in tailoring and evaluating CME programmes for GPs in Iran.