Development and Validation of Social Cognitive Theory Based Questionnaire for Physical Activity to Preventing Osteoporosis (PAQ-SCT)

Background: Social cognitive theory is a suitable model that examines many factors associated with physical activity. Despite the importance of this issue, there is no evidence of a specific questionnaire for assessing physical activity in Iranian women. Objectives: This article reports the development and psychometric evaluation process of a physical activity questionnaire among Iranian women. Methods: In 2016, this psychometric study was carried out on 400 women aged less than 50 years old from 10 health centers recruited by clustering sampling in Isfahan. After reviewing numerous texts, a questionnaire was developed and necessary reforms, in accordance with the principles of translation and cultural adaptation, were applied in a research committee. Then, content validity confirmed by an expert panel as well as face validity was evaluated in a pilot study. Construct validity was conducted using exploratory and confirmatory factor analysis. Reliability was also measured using Cronbach’s alpha coefficient and internal consistency method. Scales used in this study included self-efficacy, outcome expectations, social support, and self-regulation. Results: Internal consistency was found 0.90. In the exploratory factor analysis, four-factor models with a total variance of 80.9% were identified (P < 0.001). The CFA results (CMIN = 276/874, DF = 166, P < 0.001, CFI = 0.967, RMSEA = 0.061) represent the suitability and acceptability of a model based on social cognitive theory. Conclusions: Due to good values of validity and reliability, the questionnaire was developed based on social cognitive theory, its use is recommended to assess physical activity in Iranian women.