OBJECTIVES: Patient eligibility under the Health Effectiveness Data and Information Set (HEDIS) Asthma Medication Ratio (AMR) quality measure is evaluated based on diverse healthcare resources and medication utilization criteria. The objective was to evaluate the impact on AMR for asthma cases identified with different inclusion criteria.
METHODS: A retrospective study was conducted using Mississippi Division of Medicaid (DOM) claims data for the period January 2016 – December 2017 and the HEDIS AMR quality measure specifications. AMR was calculated as the ratio of units of asthma controller medications to total units of asthma medications in 2017. AMR ≥0.5 was used to indicate appropriate asthma medication management. Patients were assigned to cohorts based on the criterion with the greatest number of prescription events required. Cohorts were compared for performance on AMR and number of prescription units dispensed in the measurement year.
RESULTS: 10,844 beneficiaries with persistent asthma met the AMR inclusion criteria. 10,578 (97.55%) were in the cohort having 4 or more medication events (RXs), 79 (0.72%) were in the cohort with 4 outpatient visits and 2 or more medication events (OUTPT), and 187 (1.72%) only met the requirement of an emergency department or inpatient event and at least one medication event in the measurement year (EDINPT). The cohorts significantly differed on average number of asthma units in the measurement year (RXs 12.8, OUTPT 3.5, EDINPT 3.3) and AMR (RXs 59.3%, OUTPT 46.8%, and EDINPT 23.0%). The AMR including all cohorts was 58.6%.
CONCLUSIONS: This study highlights how different criteria for inclusion in the AMR measure can affect performance on the measure. Patients included based on EDINPT or OUTPT criteria with limited numbers of medication events may not truly represent persistent asthma patients. Although overall AMR changed only slightly when excluding these cohorts, health plans with larger proportions in these groups could be adversely affected.
