Morisky Medication Adherence Scale (MMAS)
Also known as: MMAS, Morisky Scale, Medication Adherence Scale
The Morisky Medication Adherence Scale is a brief, validated tool developed by Donald Morisky in 1986 to measure patients' adherence to prescribed medications. Originally created to assess hypertension medication compliance, it has since become a standard screening instrument across chronic disease management, primary care, and pharmaceutical research. The scale is valued for its brevity, ease of administration, and predictive validity for clinical outcomes.
Read the full method
Sign in with a free account to read this section.
Method map
The neighbourhood of related methods — select a node to explore.
When to use it
Use the Morisky scale in primary care and specialty outpatient clinics to screen patients with chronic conditions requiring long-term medications (hypertension, diabetes, heart disease, HIV, asthma). Administer at baseline and periodically during follow-up to monitor adherence trends and identify patients at risk of poor control. The scale is especially useful when medication efficacy is suboptimal and non-adherence is a suspected contributor. It is not intended to diagnose adherence disorders but rather to initiate discussion and implement supportive interventions.
Strengths & limitations
- Brevity and efficiency—administered in 2–3 minutes in any clinical setting with no special training required.
- Strong predictive validity—scores correlate with medication refill rates, blood pressure control, and other clinical outcomes.
- Validated across diverse populations and chronic conditions beyond the original hypertension focus.
- Directly actionable—identifies specific barriers (forgetting, side effects, cost) that guide targeted interventions.
- Social desirability bias—patients may overreport adherence due to desire to please clinician or shame about non-adherence.
- Self-report accuracy—cognitive impairment or language barriers may reduce reliability of patient responses.
- Does not assess degree of adherence—binary yes/no responses do not capture partial or intermittent non-adherence.
- Limited validity in populations with complex medication regimens or polypharmacy where adherence patterns may be heterogeneous.
Frequently asked
Does a high MMAS score guarantee good blood pressure control?
No. High MMAS scores indicate high adherence to the medication regimen as prescribed but do not guarantee therapeutic control if the regimen itself is inadequate (e.g., insufficient dose or wrong drug class). Always pair adherence assessment with clinical outcomes (blood pressure readings, lab values) and regimen review.
How should I respond if a patient reports low adherence?
First, explore the reason: is non-adherence unintentional (forgetting, confusion) or intentional (cost, side effects, lack of belief in benefit)? For unintentional non-adherence, offer reminders (alarms, pill organizers) or simplified regimens. For intentional non-adherence, discuss concerns openly, review benefits and side effects, and consider alternative medications if appropriate.
Can the MMAS be used in patients with cognitive impairment?
Use with caution. Cognitive impairment may reduce accuracy of self-report. In dementia or delirium, consider collateral history from a caregiver or family member, or use objective measures (pharmacy refill data, pill counts) to supplement the MMAS.
Is the MMAS copyrighted, and are there fees for use?
The MMAS-8 is not in the public domain, but permission to use is typically granted at no cost for research and clinical practice. Users are asked to register and acknowledge the scale developers in publications. Contact Donald Morisky or consult the scale's official website for current permissions.
Sources
- Morisky, D. E., Green, L. W., & Levine, D. M. (1986). Concurrent and predictive validity of a self-reported measure of medication adherence. Med Care, 24(1), 67-74. DOI: 10.1097/00005650-198601000-00007 ↗
How to cite this page
ScholarGate. (2026, June 3). Morisky Medication Adherence Scale (MMAS). ScholarGate. https://scholargate.app/en/nursing/morisky-medication-adherence
Which method?
Set this method beside its closest kin and read them side by side — the library lays the books on the table; the choice is yours.
Compare side by side →