Evaluating the Impact of Sample Medication on Subsequent Patient Adherence

BACKGROUND: Medication nonadherence is problematic throughout health care practice. Patient nonadherence is a result of several factors, such as financial issues, confusion about the medication, or concerns about possible side effects. Efforts to improve adherence have been implemented, but new strategies are needed to ensure that patients fill their medication prescriptions and adhere to their prescribed use. OBJECTIVE: To investigate whether providing patients with a free 30-day supply of medication at the point of care via a dispensing kiosk—a secure, computerized cabinet placed in the prescriber’s office—that provides sample medication and educational materials had a measurable impact on adherence and health care cost. METHODS: The study sample consisted of patients drawn from the electronic health records of a large health care provider who were prescribed medications to treat diabetes, hypertension, and dyslipidemia. The comparison groups included a treatment group of patients who each received a 30-day generic sample of medication and a control group of patients who did not receive a sample. The study outcome was primary medication non-adherence (PMN), defined as whether a patient filled a prescription within 90, 180, or 365 days of prescribing. Only patients receiving a prescription for the first time were considered; patients on a medication before receipt of the sample were dropped. Postprescription medication adherence (PPMA), measured as proportion of days covered (PDC) and proportion of days covered ≥ 80% (PDC80), was also examined. Propensity score methods and multivariate regression models were used to examine the outcomes and group differences. Costs to the patient before and after the prescription were also analyzed. Key informant interviews were conducted with physicians, and qualitative analyses were performed. RESULTS: Patients who received a 30-day generic medication sample had a higher probability of filling a first prescription within 90 days (72.2% for treatment patients vs. 37.6% for controls, P < 0.001); 180 days (79.1% vs. 43.3%, respectively, P < 0.001); and 365 days (85.5% vs. 48.6%, P < 0.001). The medication sample had a positive effect on PDC for 90 days, with treatment patients having 72.8% adherent days versus 35.1% adherent days for controls (average treatment effect [ATE] = 37.5%, P < 0.001). At 180 days, PDC adherence was 57.1% for treatment patients versus 35.4% for controls (ATE = 21.5%, P < 0.001), and 43.6% versus 33.9%, respectively (ATE = 9.5%, P < 0.001) for the 365-day period. PDC80 was significantly better among treatment patients at 90 days (53.5% vs. 31.2%, respectively, ATE = 22.4%, P < 0.001) and 180 days (38.4% vs. 29.1%, ATE = 9.2%, P < 0.001), but not at 365 days (23.7% vs. 23.7%, ATE = -0.02, not significant). Costs were reduced by $395 for the treatment group. Interviews with clinicians indicated a positive view of the program. CONCLUSIONS: Providing a free sample medication improved the probability of patients filling their initial prescriptions and adhering to those medications. This program can affect health care costs, as evidenced by lower costs for the treatment group.