Development and Validation of a Questionnaire to Measure Medication Adherence to Direct-Acting Agents in Patients with Hepatitis C

• Main Authors: Adina Turcu-Stiolica (Author), Irina Paula Doica (Author), Bogdan Silviu Ungureanu (Author), Ion Rogoveanu (Author), Dan Nicolae Florescu (Author), Mihaela-Simona Subtirelu (Author), Dan Ionut Gheonea (Author)
• Format: Book
• Published: MDPI AG, 2021-10-01T00:00:00Z.
• Subjects: article
• Online Access: Connect to this object online.
• Notes: 10.3390/pharmaceutics13101683; 1999-4923
• Keywords: adherence in hepatitis C; direct-acting antivirals; development and validation; Pharmacy and materia medica; RS1-441
• Source: Pharmaceutics, Vol 13, Iss 10, p 1683 (2021)

This study aims to develop a new self-report tool (HCV-AD) measuring adherence factors, intentional or unintentional, during Hepatitis C Virus (HCV) treatment with direct-acting antivirals (DAA) aiming to achieve high efficacy, otherwise resulting in drug resistance and treatment failure. Two phases were conducted: in the first phase, items were generated based on an extensive literature review, and, in the second phase, a prospective cohort study was conducted using HCV patients from Gastroenterology Department from University County Hospital of Craiova, Romania (n = 222), to evaluate the validity and reliability of the questionnaire. A number of 19 items were generated following a systematic review and through expert opinion. The internal consistency reliability was evaluated using Cronbach's alpha. The construct validity was assessed using correlations with two other instruments: visual analog scale (VAS) and medication possession ratio (MPR). The final questionnaire (HCV-AD10) was derived through exploratory factor analysis, with 82% of total variance explained. This instrument appeared as a reliable and valid measure for medication adherence, with Cronbach's alpha (0.867) and significant high positive correlations between adherence scores calculated with HCV-AD10 and VAS (ρ = 0.61, <i>p</i> < 0.001) or with HCV-AD10 and MPR (ρ = 0.75, <i>p</i> < 0.001). This research would make a worthwhile contribution to HCV management.