Suitability of Measures of Pharmacy-Based Medication Adherence for Routine Clinical Use Among Patients with Chronic Diseases: A Systematic Review

Abstract

Purpose: To identify the suitability of pharmacy-based measures for determining medication adherence in routine clinical use.

Methods: Data were obtained through PubMed and Scopus databases up to December 2023 without publication year restrictions. This review included English studies on assessing medication adherence for hypertension, hyperlipidemia, asthma, chronic obstructive pulmonary disease, and diabetes, using pharmacy databases and providing full-text access. We investigated evidence quality utilizing the Newcastle-Ottawa Scale for non-randomized studies (cohort, case-control, and cross-sectional) and the Risk of Bias Assessment Tool for Non-randomized Studies-2 and JADAD scales for quasi-experiments and randomized control trials, respectively. We determined validity characteristics (completeness, accuracy, reliability, objectivity, continuous adherence history, non-intrusiveness, sensitivity, and specificity) and applicability (cost-effectiveness, ease of use, and interpretability) to evaluate the suitability of pharmacy-based medication adherence measures in clinical settings.

Results: This review retrieved 1513 studies, of which 74 met the inclusion criteria. All of the studies, which were published from 2000 to 2023 and mostly utilized a retrospective cohort design (n = 53), included 17.6 million patients. Of the 74 studies, 50 were conducted in the United States. Diabetes mellitus (n = 40) was the most prevalent disease, whereas the medication possession ratio (n = 46) and prescription days covered (n = 31) were the most prevalent pharmacy-based matrix. According to the results, 73 articles demonstrated validity characteristics, whereas 1 article lacked these characteristics. All 74 (100%) articles had applicability characteristics.

Conclusion: This systematic review demonstrates that pharmacy-based measures possess valid characteristics, including comprehensive, accurate, objective, reliable, and continuously updated adherence history records. These measures are designed to minimize disruption while offering high sensitivity and specificity. Furthermore, they are characterized by their practicality, being cost-effective, easy to implement, and easy to interpret. These findings suggest that pharmacy-based measures are potentially suitable to assess medication adherence for routine clinical use.

Keywords: applicability; chronic disease; medication adherence; medication possession ratio; pharmacy fill; proportion of days covered; routine clinical use; suitability; validity.

Figure 1

PRISMA Flow Diagram. Adapted from Page MJ, McKenzie JE, Bossuyt PM, et al. The PRISMA 2020 statement: an updated guideline for reporting systematic reviews. BMJ. 2021; 372 :n71. Creative Commons.