Washington State CARE Project: downstream cost changes associated with the provision of cognitive services by...

To determine the changes in drug costs associated with drug therapy changes resulting from pharmacists' cognitive services (CS) provided to Medicaid recipients during a 1-year period following the documented CS.

A study-control group analysis of documented pharmacists' CS interventions linked to Medicaid prescription claims. Each CS resulting in a drug therapy change was linked to an index prescription claim and all refills for the same drug within 365 days. The drug cost change associated with the CS was calculated as the difference between the estimated cost of the prescription as originally written less the actual cost to Medicaid for the stream of refills dispensed.

Pharmacies serving ambulatory Medicaid patients in the state of Washington, excluding staff-model health maintenance organization pharmacies and pharmacies predominantly serving long-term care residents.

Approximately 200 community pharmacies participating in the Washington State Cognitive Activities and Reimbursement Effectiveness (CARE) Project. Pharmacies were randomly assigned to a group that was paid a fee for each CS provided or a group that was not paid.

Payment for CS.

Downstream drug costs associated with CS resulting in a drug therapy change.

CS resulting in drug therapy changes accounted for 5,417 out of 20,240 (27%) documented CS in the CARE Project. Of the 2,002 CS records analyzed in this study, 76% indicated a change in the prescribed drug or drug regimen, 9% indicated that a drug was added, 5% indicated that a current drug was discontinued, and 10% indicated that an originally prescribed drug was never dispensed. Only 9% involved generic substitution; all other changes would have necessitated prior prescriber approval. Overall, CS resulting in a drug therapy change generated a mean drug cost savings of $13.05 per CS intervention. There were no significant differences in average savings per intervention between the paid and nonpaid groups.

For all result categories except "add drug therapy," the extrapolated cost savings in the paid group exceeded the savings estimated from the nonpaid group, sometimes by a considerable amount. At the payment rate used in this study, paying for CS that result in a drug therapy change (except add drug therapy) is estimated to save an additional $10 per 1,000 prescriptions dispensed. Those CS that result in addition of drug therapy are estimated to add an incremental cost of about $13 per 1,000 prescriptions. A sensitivity analysis revealed that a higher intervention rate would lead to a higher potential savings. This finding suggests that efforts to encourage CS interventions may lead to greater savings.