Development and Preliminary Psychometric Evaluation of the Intradialytic Hypotension-Related Health Beliefs Scale for Patients Undergoing Maintenance Hemodialysis

To develop the Intradialytic Hypotension (IDH)-Related Health Beliefs Scale for patients undergoing maintenance hemodialysis (MHD) and preliminarily evaluate its psychometric properties.

A multistage scale-development study combined literature review, patient interviews, Delphi consultation, and pretesting. Convenience sampling recruited 451 patients from four tertiary hospitals in China. Before item analysis, participants were randomly divided into development (n=226) and validation (n=225) samples. The development sample was used for item analysis and exploratory factor analysis (EFA), whereas the validation sample was used for confirmatory factor analysis (CFA) and evaluation of convergent and discriminant validity. Content validity, known-groups validity, internal consistency, test-retest reliability, and score distributions were also examined.

The final scale contained 29 items across four domains: perceived susceptibility, perceived severity, perceived benefits, and self-efficacy. EFA supported a four-factor structure explaining 65.29% of item variance. After two content-justified post hoc within-domain residual correlations were specified, CFA fit was acceptable (CFI=0.978, TLI=0.976, RMSEA=0.064, SRMR=0.061). The scale-level content validity index using the average method (S-CVI/Ave) was 0.969. Across domains, Cronbach's α ranged from 0.794 to 0.922, McDonald's ω from 0.805 to 0.961, and 2-week intraclass correlation coefficients from 0.839 to 0.894. Three of six prespecified known-groups hypotheses were supported. The self-efficacy domain showed a 34.37% ceiling effect.

To our knowledge, this is the first patient-reported instrument developed specifically to assess IDH-related health beliefs in this population. The findings provide preliminary evidence for its four-domain structure, reliability, and validity. Scores should be calculated and interpreted by domain. The scale may help identify priorities for patient education and risk communication but cannot replace objective clinical assessment. Independent multicenter and longitudinal validation is required before routine use.