Assessing the utilization and productivity of nurse practitioners and physician's assistants: methodology and...

This article describes the research design, survey instrument and methodology employed in a national study to assess the utilization and productivity of nurse practitioners and physician assistants (NP/PAs) in primary care settings. All practices (N = 455) used in the study employed formally trained NP/PAs who treated, or were eligible to treate, Medicare patients on an outpatient basis, and included a general practitioner, family practitioner or a general internist as the supervising physician. A matched group of comparison practices were subject to the same eligibility criteria except that they did not employ NP/PAs. A comprehensive diary-type instrument focusing on patient care was used to collect detailed data on each practitioner's daly professional activities. Data are presented on the productivity of NPs, PAs and physicians as measured by seven basic variables related to patient volume, time in patient care and revenue generated. Numerous inter- and intraspecialty comparisons were made across various practice arrangements and across location variables such as rural vs. urban, remote vs. nonremote, and health care resource areas. Interpretations of the data indicate clearly that PAs are considerably more productive than NPs. However, although NPs spend more time with individual patients, the cause of this differential productivity was not revealed.