A model-guided process evaluation: Office-based prescribing and pharmacy dispensing of methadone

This article presents an exemplar of a model-guided process evaluation that specifies the treatment model, assesses its implementation, monitors the fidelity of the model throughout the project, assesses model exposure and absorption, and helps understand the program's intermediate effects (proximal outcomes) as well as final effects (distal outcomes). The New Mexico study on office-based prescribing and community pharmacy dispensing of methadone is a research demonstration project that phases a small group of female methadone maintenance patients out of methadone clinics and into a program where they will obtain their scheduled doses of methadone at pharmacies that work in collaboration with physicians and a social worker.The patient's methadone treatment will in this way become part of their overall health care. Early detection of problems of implementation (e.g., the omission of program content or the delivery of inaccurate information) enables the researcher to make adjustments before the problems become unmanageable and the integrity of the original research design is compromised. A model-guided process evaluation can critically inform health services research demonstrations designed for enabling continuous, ongoing feedback and improvement of client-related services.