The Medication Adherence Report Scale: A measurement tool for eliciting patients' reports of nonadherence

Abstract

This study aimed to establish the psychometric properties of a questionnaire measure of patients' adherence to medications to elicit patients' report of medication use in a variety of clinical samples. The reliability and validity were assessed in patients with hypertension. Additional analyses were performed on other patient groups.Methods: Using a cross-sectional study design, a 10-item version of the Medication Adherence Report Scale (©Professor Rob Horne) was piloted in two samples of patients receiving treatment for hypertension (n = 50 + 178), asthma (n = 100) or diabetes (n = 100) at hospital outpatient or community clinics in London and the southeast of England. Following principal components analysis, five items were retained to form MARS-5 (©Professor Rob Horne). Evaluation comprised internal reliability, testretest reliability, criterion-related validity (relationship with blood pressure control) and construct validity (relationship with patients' beliefs about medicines). Results:The MARS-5 demonstrated acceptable reliability (internal and test-retest) and validity (criterion-related and construct validity) in these patient groups. Internal reliability (Cronbach's α) ranged from 0.67 to 0.89 across all patient groups; testretest reliability (Pearson's r) was 0.97 in hypertension. Criterion-related validity was established with more adherent hypertension patients showing better blood-pressure control (χ 2 = 4.24, df = 1, P < .05). Construct validity with beliefs about medicines was demonstrated with higher adherence associated with stronger beliefs in treatment necessity and lower treatment concerns. Conclusions:The MARS-5 performed well on several psychometric indicators in this study. It shows promise as an effective self-report tool for measuring patients' reports of their medication use across a range of health conditions.

Modifiable Factors Associated with Non-adherence to Antihypertensive or Antihyperlipidemic Drugs Are Dissimilar: a Multicenter Study Among Patients with Diabetes in Indonesia

“…Adherence was assessed using the Medication Adherence Report Scale (MARS), which has shown to perform well on a number of psychometric indicators and internal-reliability. 28 The MARS has been translated and validated to Indonesian and showed to be valid and reliable. 29 The MARS contains one item that reflects unintentional non-adherence ("I forget to take my lipid-lowering medicines") and four items that largely reflect different forms of intentional non-adherence (e.g., "I alter the dose of my lipid-lowering medicines").…”

“…29 The MARS contains one item that reflects unintentional non-adherence ("I forget to take my lipid-lowering medicines") and four items that largely reflect different forms of intentional non-adherence (e.g., "I alter the dose of my lipid-lowering medicines"). 28 Patients indicate how often each item applied to them in the last 3 months on a 5-point Likert scale, where 5, "never"; 4, "rarely"; 3, "sometimes"; 2, "often" and 1, "always". 28 Nonadherence is defined as a score of 1 to 3 on any of the items, and adherence as a score of 4 or 5 on all items allowing for rarely missing or changing a dose.…”

“…28 Patients indicate how often each item applied to them in the last 3 months on a 5-point Likert scale, where 5, "never"; 4, "rarely"; 3, "sometimes"; 2, "often" and 1, "always". 28 Nonadherence is defined as a score of 1 to 3 on any of the items, and adherence as a score of 4 or 5 on all items allowing for rarely missing or changing a dose. We defined the subtypes of non-adherence a priori as follows:…”

Determinants of Uncontrolled Asthma Among Adult Asthmatic Patients on Follow-Up at Chest Clinic of Jimma Medical Center: Unmatched Case-Control Study

“…Data were collected using a structured questionnaire adopted from different literatures (2,(25)(26)(27)(28)(29)(30). The English version of the questionnaire was translated into the local language and back-translated to English to maintain its consistencies.…”

“…Medication adherence was evaluated using the Medication Adherence Report Scale (MARS-5) which is a ve-item questionnaire rated on a ve-point Likert scale. Asthmatic patients who scored 23 or above were categorized as adherent to medication while those who scored less than 23 were categorized as nonadherent (27).…”