The clinical biochemistry laboratory computer system and result entry: validation of analytical results.

We describe an array of checking routines that can aid laboratory staff in detecting possible errors in results being entered into a laboratory computer. A single result is checked at the worksheet stage for its numeric format and for its numeric status by comparison with appropriate reference ranges, and action and hazard limits. If a previous result exists then the present result can be compared with it (delta checking). Laboratory documentation of abnormal results is important and we describe three types; worksheet, exception report(s) and histograms of results. The clinical reports leaving the laboratory should flag abnormal results so that the clinician is prompted to examine, and question if necessary, results which are extreme or have changed significantly since the last analysis. Effective error detection requires cooperation between the laboratory and clinical units.