Six-year trends in productivity and utilization of 73 clinical laboratories: a College of American Pathologists Laboratory Management Index Program study.

OBJECTIVES To describe longitudinal trends in the efficiency, labor productivity, and utilization of clinical laboratories in the United States. METHODS Financial and activity data were prospectively collected from 73 clinical laboratories continuously enrolled in the College of American Pathologists Laboratory Management Index Program from 1994 through 1999. Each laboratory reported quarterly on its costs, labor inputs, and test activity using uniform data definitions. RESULTS During the 6-year study period, there was a significant increase in laboratory labor productivity (2.1% more tests/full-time equivalent/y; P <.001). Productivity increases were offset by increasing labor expense (1.5%/full-time equivalent/y; P <.001), consumable expense (1.7%/on-site test/y; P =.005), and blood expense, which comprised more than 10% of laboratory expenses by 1999 (4.4% increase/y; P <.001). As a result, overall expense per test showed no significant change in non-inflation-adjusted dollars. Reference laboratory expense per test did not change significantly during the study period; the proportion of tests sent to reference laboratories grew slightly (0.06% increase/y; P <.001). Test volume of the median laboratory grew by 5442 tests per year (2.3% annual increase; P <.001), while the proportion of testing from inpatients declined by 1.7% per year (P <.001). Inpatient test utilization declined on a discharge basis (annual decline of 1.2 tests/inpatient discharge; P <.001) and on a per diem basis (annual decline of 0.08 tests/inpatient day; P =.002). Inpatient laboratory expense declined on a discharge basis (annual decline of $2.40 or 1.3% per discharge; P <.001), but did not change significantly per inpatient day. Most of the reduction in the expense per discharge occurred during 1994-1996. CONCLUSIONS Between 1994 and 1999, clinical laboratories in the United States experienced significant changes in the cost of operations, utilization, and labor productivity. Laboratory administrators who compare local institutional performance with that of peers are advised to use current or forward-trended peer data. Quarter-to-quarter improvement in many measures of laboratory financial activity may not signal a superior operation, as performance of the whole industry appears to be improving.