Development, reliability and validity of health action process approach questionnaire for predicting treatment adherence among Iranian hemodialysis patients

End-stage renal disease (ESRD) is an advanced stage of chronic kidney disease requiring hemodialysis (HD). The long-term efficacy of HD in ESRD patients highly depends on treatment adherence.

This study aimed to validate the health action process approach (HAPA) questionnaire to predict treatment adherence in HD patients. Patients and

This cross-sectional study was conducted in in three teaching and two private hospitals in Shiraz during 2018. A total of 220 patients with ESRD under HD were selected using convenience sampling method. Furthermore, the validity, clarity, and comprehensiveness of the questionnaire were validated by a group of patients and experts. Then the exploratory factor analysis (EFA) was performed, and the reliability was determined using Cronbach’s alpha. Internal consistency was assessed using test-retest method (one-month interval) and calculating intra-class correlation coefficient (ICC) index.

Content validity index (CVI) and content validity ratio (CVR) were obtained 0.98 and 0.95 respectively indicating adequate content validity. Six constructs (risk perception, action self-efficacy, behavioral intention, planning, maintenance self-efficacy and recovery self-efficacy) were extracted using EFA. These constructs explained 51.4% of total variance. The Cronbach’s alpha of different constructs ranged from 0.68 to 0.82. Furthermore, the ICC ranged from 0.67 to 0.78 indicating an acceptable internal consistency.

The HAPA questionnaire is a valid and reliable tool for assessing treatment adherence in HD patients. Further studies are recommended on larger sample sizes and other Iranian populations.