Development of the Well-being questionnaire short-form in Japanese: the W-BQ12

BACKGROUND The Well-being Questionnaire (W-BQ) was designed to measure psychological well-being in people with diabetes. This study aimed to develop a Japanese version and a short form of the W-BQ. METHODS A linguistic validation process produced a preliminary Japanese version of the 22-item W-BQ, which was distributed to 550 patients. Factor structure, reliability (Cronbach's alpha) and aspects of validity (hypothesised group differences and correlations with other measures) were evaluated. RESULTS Questionnaires were returned by 464 patients (84.4%). Preliminary factor analysis revealed that the Depression and Anxiety items were dispersed according to the positive or negative direction of the wording. A 12-item W-BQ (Japanese W-BQ12), consisting of three 4-item subscales (Negative Well-being, Energy and Positive Well-being), was constructed that balanced positively and negatively worded items. Cronbach's alpha was high (>0.85) for the 12-item questionnaire and consistently high (>0.82) across sex and treatment subgroups. Cronbach's alpha for subscale scores in the total sample ranged from 0.69 (Energy) to 0.80 (Positive Well-being). Expected subgroup differences indicated significantly poorer well-being in women compared with men and in insulin-treated patients compared with tablet/diet treated patients. Discriminant and convergent validity was supported by minimal correlations between W-BQ12 scores and HbA1c and low-to-moderate correlations with Diabetes Treatment Satisfaction Questionnaire (DTSQ) scores. CONCLUSION The W-BQ12 (Japanese) is a short, reliable and valid measure of psychological well-being that is suitable for use with people with diabetes. The items selected to produce the W-BQ12 (Japanese) have since produced psychometrically sound 12-item short-form measures in other translations for use in diabetes and in other chronic illnesses.