An interpractice visit study.

In general terms the tests are performed to monitor disease or therapy, to help in reaching or excluding a diagnosis, and to screen for significantly treatable abnormalities in apparently healthy people either in the population at large (as in hyperlipidaemia) or in a specific risk group, for example, relatives of colorectal cancer sufferers. The result of the test gives some indication of its value in diagnosis. A preponderance of abnormal results suggest that it adds little to the clinical acumen of the observer, while in the opposite situation a high proportion of normal results suggest that it is being wrongly applied. Where the purpose is monitoring, the survey should throw some light on the value and frequency of use of the test. How often does the discerning general practitioner order routine electrolytes, serum digoxin levels, thyroid function tests? And, more significantly, how often should this be done? General practitioners are the appropriate people who can find out and establish an accepted standard. In screening it should be possible to demonstrate both the value of the test in terms of detection rate (ratio of normal to abnormal results) and the efforts of an individual practitioner in preventive medicine expressed as proportion of total work load. Suitably expanded it could be extended to discover the proportion of the total population at risk that is being reached by screening. This writer believes that general practice lacks a published body of knowledge culled from its collective experience on which it can call when challenged by colleagues, government or even hostile barristers.(ABSTRACT TRUNCATED AT 250 WORDS)