Development of the NIH Patient-Reported Outcomes Measurement Information System (PROMIS) Medication Adherence Scale (PMAS)

Poor medication adherence is associated with reduced drug effectiveness, poor health-related quality of life, increased morbidity and mortality, and increased healthcare utilization and cost. Including the patient’s voice is essential in understanding barriers to adherence. Useful patient-reported adherence measures are brief, inexpensive, non-invasive; can indicate barriers to adherence; and can be incorporated in electronic health records. The NIH Patient-Reported Outcomes Measurement Information System (PROMIS(®)) includes high-quality, freely available patient-reported measures covering many important constructs in patient-centered research but does not include a medication adherence measure. To fill this gap, we developed the PROMIS Medication Adherence Scale (PMAS) using the rigorous PROMIS instrument development guidelines. To develop the PMAS, we first conducted a review of the reviews, which enabled us to identify content areas relevant to medication adherence behavior. Then, we conducted qualitative research to elicit patients’ views of and experiences with medication adherence. This process identified the following important content areas to guide item writing: extent medication is taken, knowledge of medication regimen, beliefs about medication, remembering to take medication, skipping due to side effects, skipping due to feeling better, and cost of medications. Based on the results of these activities, we wrote items and aimed to retain 1–2 items per content area. The final item set included 9 total adherence items, which were then refined through intensive comprehension and translatability review, as well as cognitive interviews. Future steps include testing the PMAS’s validity.