Background: Control of high blood pressure and prevention of cardiovascular complications among hypertensive patients depends on patients' adherence to therapy. The Hill-Bone Compliance to High Blood Pressure Therapy Scale (HBCTS) is one of the most popular scale to assess hypertensive patients' adherence behaviour. Unfortunately, no questionnaire in the Nepalese language is available to date to assess adherence to anti-hypertensive therapy.
Aim: To translate, culturally adapt and validate the English original version of the HBCTS into Nepalese language to measure treatment adherence of Nepalese hypertensive patients.
Methods: The cross-sectional study was conducted to translate, culturally adapt and validate the HBCTS into Nepalese version. The standard translation process was followed and was evaluated among 282 hypertensive patients visiting selected primary healthcare centers (PHCCs) of Kathmandu district, Nepal. Cronbach's alpha was measured to assess the reliability of the tool. Exploratory factor analysis using principal component analysis with varimax rotation was used to evaluate structural validity.
Results: The mean±SD age of 282 participants was 58.49±12.44 years. Majority of participants were literate (75.2%), and consumed at least one anti-hypertensive medication per day (85.5%). Nearly half (42.2%) of the participants had a family history of hypertension, and almost half (48%) of them had comorbid conditions. Mean ±SD score for overall adherence was 17.85±3.87 while those of medication taking, reduced salt taking, and appointment keeping subscales were 10.63±2.55, 4.16±1.12 and 3.06±1.07, respectively. Kaiser Meyer Olkin (KMO) was found to be 0.877. Exploratory factor analysis revealed a three-component structure; however, the loading of components into medication adherence, reduced salt intake and appointment keeping constructs were not identical to the original tool. Cronbach's alpha score for the entire HBCTS scale was 0.846.
Conclusion: The translated Nepali version of the HBCTS demonstrated acceptable reliability and validity to measure adherence to antihypertensive therapy among hypertensive patients in clinical and community settings in Nepal.