Survey of office laboratory tests in general practice.

OBJECTIVE

To describe the types of laboratory test done in general practice, and to investigate whether practice characteristics were associated with the implementation of certain tests or instruments.

SETTING

A questionnaire was mailed to an 8% random sample of Norwegian GPs.

RESULTS

85% responded; and we obtained data from 175 office laboratories. Medical secretaries did most of the analytical work. The "basic" repertoire consisted of haemoglobin, ESR, glucose; urine test strips, microscopy, culture, and HCG; and faecal occult blood. Group practices had a larger repertoire than had solo practices. Overall, 34% of the practices had urine strips with fields for leucocytes and nitrite, 26% had a cell counter, and 17% did clinical chemistry. A large number of different test methods and instruments were in use, but in most cases one or two brands had a market share of more than 50%. Logistic regression showed that employing a medical laboratory technician was associated with a large analytical repertoire, and the use of cell counters and clinical chemistry analyzers. The GP's form of payment (fixed or fee-for-service) did not influence the repertoire.

CONCLUSIONS

The diversity of test methods and instruments makes quality assurance difficult, and recommendations are overdue.