The development and validation in hypertensive patients of the Health Belief Model for pharmacological adherence (HBM-FA) scale

Introduction: pharmacological adherence in hypertensive patients is essential, so the study of the factors that influence it is essential.Objective: to develop and validate a scale based on the health belief model to measure factors influencing drug adherence in hypertensive patients.Methods: the development process of the HBM-FAS scale included the review of the literature, the generation of the items that conformed it (grouped in the six constructs that respond to the theoretical framework of the Health Belief Model), the evaluation of its content by a panel of experts, and the subsequent application of a pilot test. A confirmatory factor analysis of the proposed model was carried out, and its validity and reliability were subsequently evaluated. Results: a panel of experts evaluated the content validity of the instrument, showing a high degree of content validity. The CFA indicated poor fit indices (CFI=.763; TLI=.735; RMSEA=.118; SRMR=.143; CMIN/DF=.07), leading to modifications (removal of 9 out of 30 items). The refined model showed an acceptable fit (CMIN/DF=1.69; CFI=.977; TLI=.972; SRMR=.0393; RMSEA=.0434). The scale demonstrated high internal consistency reliability (.895) as well as good discriminant validity.Conclusions: the HBM-FA scale showed good psychometric properties, being suitable for measuring health beliefs associated with pharmacological adherence in hypertensive patients, which makes its use in future intervention studies beneficial.