Development and psychometric evaluation of the healthy lifestyle questionnaire for elderly (heal)

Background The present study was conducted to design and evaluate the psychometric properties of a questionnaire for assessing the healthy lifestyle among older adults in Iran. Methods First, items were generated based on a qualitative study, the literature review, and with help received from experts in gerontology and questionnaire design. Then, content validity was carried out. Accordingly, a cross sectional study was conducted to perform factor analysis and known groups comparison in order to examine the construct validity. Internal consistency was measured by the Cronbach's alpha coefficient and the stability of the questionnaire was evaluated by estimating interclass correlation coefficient (ICC). Results In total 68 items was generated. Following development process 22 items were removed and a provisional version of the questionnaire with 46 items was subjected to psychometric evaluation. At this stage a sample of 390 elderly people attending the community centers in Tehran, Iran were entered into the study and completed the questionnaire. Most elderly were female (52.8%) and the mean age of participants was 67.97 (SD +/- 7.77) years. After performing factor analysis, overall 10 items were removed due to low loading and the questionnaire was reduced to 35 items tapping into eight factors, which explained a total of 57.1% of the variance. In addition, the results obtained from known groups comparison indicated that the questionnaire well differentiated among participants who were differed in self-reported health condition. The Cronbach's alpha coefficient showed excellent internal consistency (alpha = 0.89). The intraclass correlation coefficient also indicated a good stability for the questionnaire (ICC = 0.94). Conclusion The healthy lifestyle questionnaire for elderly (Heal) can be used as a simple and an easy-to-use valid and reliable measure in determining healthy life style and the frequency of health-oriented activities among older adults.