Longitudinal trends in laboratory test utilization at a large tertiary care university hospital in Sweden

The aim of the study was to describe and evaluate longitudinal trends in laboratory test utilization over a 7-year period from 2002 to 2008.

Retrospective study using test request data from the Clinical Chemistry and Pharmacology Laboratory at Akademiska Sjukhuset, a large tertiary care university hospital in Sweden. Changes in test utilization, charges, and expenditures during the study period were used as main outcome measures.

Laboratory test utilization increased by over 70%, with a mean annual increase of 9.3% during the study period. After adjustment for inflation, the laboratory expenditures increased by 20.2% during the study period but represented only approximately 2.0% of the hospital's total expenditure in 2008. The test menu comprised 663 tests in 2008, an increase by 146% from 2002. The mean inflation-adjusted unit price charged per test increased from €34.9 to €37.5 during the study period. The top 10, 20, and 30 tests accounted for, on average, 46.9%, 66.9%, and 75.5% of the total test volume during the study period, and 47.8%, 66.4%, and 75.7% of the total test volume in 2008. In 2008, 10 analyses, i.e. 1.5% of the number of tests on the menu, accounted for almost half the number of generated test results.

The total number of generated test results increased by over 70% in less than a decade. Even so, the laboratory's share of the hospital's total expenditure remained low and virtually unchanged. A very small number of tests accounted for a disproportionately large share of the total number of generated test results.