Performance requirements of tests performed nearer the patient.

Commercial test systems which can be used outside the laboratory are proliferating, but there are doubts about the quality of results obtained when they are used by unskilled staff. Although rapid but approximate results can be invaluable in some clinical situations, they can be disastrous in others, particularly when the results conflict with those obtained by conventional laboratory techniques. The clinician needs to define his requirements for the quality of such tests, and the manufacturer encouraged to produce equipment which gives accurate results, independent of the skill of the operator. The laboratory scientist has an important role in the development and effective application of tests performed nearer the patient.