RESUMEN
BACKGROUND: Many U.S. states have legislated to allow nurse practitioners (NPs) to independently prescribe drugs. Critics contend that these moves will adversely affect quality of care. OBJECTIVE: To compare rates of inappropriate prescribing among NPs and primary care physicians. DESIGN: Rates of inappropriate prescribing were calculated and compared for 23 669 NPs and 50 060 primary care physicians who wrote prescriptions for 100 or more patients per year, with adjustment for practice experience, patient volume and risk, clinical setting, year, and state. SETTING: 29 states that had granted NPs prescriptive authority by 2019. PATIENTS: Medicare Part D beneficiaries aged 65 years or older in 2013 to 2019. MEASUREMENTS: Inappropriate prescriptions, defined as drugs that typically should not be prescribed for adults aged 65 years or older, according to the American Geriatrics Society's Beers Criteria. RESULTS: Mean rates of inappropriate prescribing by NPs and primary care physicians were virtually identical (adjusted odds ratio, 0.99 [95% CI, 0.97 to 1.01]; crude rates, 1.63 vs. 1.69 per 100 prescriptions; adjusted rates, 1.66 vs. 1.68). However, NPs were overrepresented among clinicians with the highest and lowest rates of inappropriate prescribing. For both types of practitioners, discrepancies in inappropriate prescribing rates across states tended to be larger than discrepancies between these practitioners within states. LIMITATION: The Beers Criteria addresses the appropriateness of a selected subset of drugs and may not be valid in some clinical settings. CONCLUSION: Nurse practitioners were no more likely than physicians to prescribe inappropriately to older patients. Broad efforts to improve the performance of all clinicians who prescribe may be more effective than limiting independent prescriptive authority to physicians. PRIMARY FUNDING SOURCE: The Robert Wood Johnson Foundation and National Science Foundation.