Psychometric testing of an instrument designed to measure nutritional perceptions of hypertensive patients
نویسندگان
1 Food Security Research Center
2 Department of Epidemiology and Biostatistics, School of Health, Isfahan University of Medical Sciences, Isfahan,
3 Public Health Department, School of Health, Qom University of Medical Sciences, Qom, Iran
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doi
چکیده
Introduction: Measurement tools designed to ensure the achievements of studies’ objectivesmust be evaluated. Based on the health promotion model (HPM), the present study wasconducted to assess the validity and reliability of the designed questionnaire of hypertensivepatients’ nutritional perceptions. Methodology: In a cross‑sectional study, the mentionedquestionnaire was assessed based on opinions of 11 experienced faculty members and671 hypertensive patients in rural areas in the year 2013. To evaluate the reliability, internalconsistency (Cronbach’s alpha) was calculated. Concerning the validity of the questionnaire,its content and construct validity were examined. Data analysis was performed usingStatistical Package for the Social Sciences version 18 (SPSS Inc., Chicago, IL, USA).Results: Spearman‑Brown and Cronbach’s alpha coefficients results were acceptable in allconstructs indicating a satisfactory reliability of the questionnaire. Questionnaire’s questionswere highly correlated with the total score signifying the internal consistency of the questions;therefore, all questions had a similar effect on the total score and the removal of each did noincrease the alpha significantly (all questions had acceptable reliability). Factor analyses showedthat all questions had acceptable factor loading and suitable validity. Moreover, the entireconstructs of the questionnaire were approved by experts with high validity coefficient of 0.9.Conclusion: The designed questionnaire for assessment of the HPM constructs regardinghypertensive patients’ nutritional issues had appropriate psychometric characteristics. Reliabilityand validity of the questionnaire were also satisfactory and its overall structure was approved.
