An aid to reducing unnecessary investigations.

The number of investigations carried out on patients with the same condition varies greatly. The reason is largely inappropriate investigation. The known progressive increase in the use of laboratory facilities could be slowed down if unnecessary tests were eliminated. A computer-based medical information system, house officer information system, was used to eliminate the ordering of unnecessary tests. Analysis showed that patients cared for while the system was in operation were less likely to have unnecessary tests, which lead to a saving of pound1.34 per patient in laboratory costs.