RESUMO
BACKGROUND: Osteoporosis is a common disease in women over age 45 years. Calcium intake is among the factors that help prevent osteoporosis. Identifying the social-cognitive determinants of calcium intake can have a major role in the development of osteoporosis prevention programs. MATERIALS AND METHODS: This cross-sectional study was conducted on 400 women aged <50 years from 10 health centers by cluster sampling in Isfahan in 2016. A hypothetical social-cognitive model was assessed using path analysis, and the fit indices and explanatory power of the model were assessed. The constructs, including self-efficacy, outcome expectations, social support, and self-regulation, were taken as the explanatory variables and calcium intake as the criterion variable. RESULTS: The mean age of the participating women was 34.07 years (standard deviation = 7.99) (range = 19-50), and their mean calcium intake was reported as 909.94 (12. 6) mg/day. The conceptual model was able to explain 73% of the variance in calcium intake and had good fit indices. Self-regulation was identified as the strongest predictor of calcium intake, and outcome expectation was eliminated from the model since it was the weakest explanatory factor of calcium intake. CONCLUSIONS: The theoretical model of this study is recommended as a suitable framework for the development of targeted osteoporosis prevention interventions.
RESUMO
Background: Osteoporosis is common among women which may be mostly due to the low intake of calcium. This article reports the development, cultural adaptation and psychometric properties of a Calcium Intake Questionnaire based on the social cognitive theory (CIQ-SCT)among Iranian women. Methods: In 2016, this cross-sectional study was carried out among 400 younger than 50 years old women in Isfahan, Iran. After literature review, a preliminary 35-item questionnaire was developed. Then, forward-backward translation and cultural adaptation of the tool was conducted. Content Validity Index confirmed by an expert panel and Face Validity was evaluated in a pilot study. Exploratory and confirmatory factor analyses (EFA &CFA) were conducted on the calibration and validation sample, respectively. Reliability was also assessed using internal consistency test. Results: After determining content and face validity, 20 items with 5 factors (self-efficacy,outcome expectations, social support and self-regulation) were obtained. Cronbach alpha for the instrument was found to be 0.901. In EFA, we identified a 4-factor model with a total variance of 72.3%. The results related to CFA (CMIN/DF=1.850, CFI =0.946, TLI=0.938, RMSEA=0.069[90% CI: 0.057-0.081]) indicated that the model was fit to the social cognitive theory. Self regulation was detected as the best predictor for calcium intake. Conclusion: The CIQ-SCT showed acceptable levels of reliability and validity in explaining the calcium intake based on the constructs of social cognitive theory. Further psychometric testing is recommended in different population to approve the external validity of the instrument.