Development and Psychometric Evaluation of the Self-Efficacy for Appropriate Medication Use Scale (SEAMS) in Low-Literacy Patients With Chronic Disease

Abstract

Medication nonadherence remains a significant obstacle to achieving improved health outcomes in patients with chronic disease. Self-efficacy, the confidence in one's ability to perform a given task such as taking one's medications, is an important determinant of medication adherence, indicating the need for reliable and valid tools for measuring this construct. This study sought to develop a self-efficacy scale for medication adherence in chronic disease management that can be used in patients with a broad range of literacy skills. The Self-efficacy for Appropriate Medication Use (SEAMS) was developed by a multidisciplinary team with expertise in medication adherence and health literacy. Its psychometric properties were evaluated among 436 patients with coronary heart disease and other comorbid conditions. Reliability was evaluated by measuring internal consistency and test-retest reliability. Principal component factor analysis was performed to evaluate the validity of the SEAMS. Reliability and validity analyses were also performed separately among patients with low and higher literacy levels. The final 13-item scale had good internal consistency reliability (Cronbach's alpha = 0.89). A two-factor solution was found, explaining 52.3% of the scale's variance. The scale performed similarly across literacy levels. The SEAMS is a reliable and valid instrument that may provide a valuable assessment of medication self-efficacy in chronic disease management, and appears appropriate for use in patients with low literacy skills.

Improving Medication Adherence through Graphically Enhanced Interventions in Coronary Heart Disease (IMAGE-CHD): A Randomized Controlled Trial

“…One possible explanation is that, although health literacy may be indirectly associated with medication management, 2,[40][41][42][43] other factors such as medication understanding and self-efficacy are more closely related to adherence behavior. 27 Our stratified analyses suggest that, rather than targeting patients on the basis of low health literacy, adherence interventions should be directed toward patients with low medication selfefficacy, a complex medication regimen, or evidence of non-adherence.…”

“…27 The SEAMS is a validated, reliable (Cronbach's α=0.89), 13-item instrument; scores may range from 13 (low self-efficacy) to 39 (high self-efficacy). The validated 4-item Morisky Medication Adherence Scale (MMAS) assessed baseline adherence on a scale of 4 (poor) to 8 (good).…”

The Pharmacist Role in Predicting and Improving Medication Adherence in Heart Failure Patients

“…62 The Self-Efficacy for Appropriate Medication use Scale (SEAMS) is a 13-item tool that was evaluated in low-literacy patients with coronary heart disease and other comorbid conditions, with good internal consistency. 63 The Hill-Bone Compliance to High Blood Pressure Therapy Scale is a 14-item scale, focused specifically on hypertension. 64 All 4 of these tools are not especially practical for routine clinical use because of their length, and only the ASK-20 was specifically assessed in HF patients.…”

“…64 All 4 of these tools are not especially practical for routine clinical use because of their length, and only the ASK-20 was specifically assessed in HF patients. [61][62][63][64] While the development of adherence screening tools has been an active area of clinical research in recent years, further work is needed to create a tool that will be applicable to a HF population in clinical practice. At the present time, the MMAS and the Merck Adherence Estimator may be potentially useful for pharmacists or other health care providers in identifying nonadherence in HF patients.…”

Comparison of Student and Patient Perceptions for Medication Non-adherence

“…Medication Use Scale, 25 ASK-20, 26 and the Hill-Bone Compliance Scale. 27 Some scales measured general non-adherence and some were developed for use in specific disease states.…”