The latest version of our Laboratory Information System haematology laboratory expert system that handles the output of Abbott Cell-Dyn Sapphires, CD4000s and a CD3200 full blood count analyser in three high-volume haematology laboratories is described. The three hospital laboratories use Cerner Millennium Version 2007.02 software and the expert system uses Cerner Millennium Discern Expert rules and some small Cerner Command Language in-house programs. The entire expert system is totally integrated with the area-wide database and has been built and maintained by haematology staff members, as has the haematology database. Using patient demographic data, analyser numeric results, analyser error and morphology flags and previous results for the patient, this expert system decides whether to validate the main full blood count indices and white cell differential, or if the analyser results warrant further operator intervention/investigation before verifying, whether a blood film is required for microscopic review and if abnormal results require phoning to the staff treating the patient. The principles of this expert system can be generalized to different haematology analysers and haematology laboratories that have different workflows and different software.

Summary A computer‐based expert system is described which handles the output of the Technicon H1 in the haematology laboratory of a large teaching hospital. Using patient request data, analyser results, error and morphology flags, the expert system decides: whether to validate the main indices plus differential; whether a blood film is required for manual review; and which abnormal results require phoning to the requesting doctor. The results of this computer‐assisted analysis are sent to a printer adjacent to the analyser. The print‐out details any further action required of the operator before release of results to the main hospital computer, and serves as a log of all samples run on that analyser. Benefits of the expert system include greatly simplified interpretation of the large array of analyser flags, and consistency in sample handling for all operators over all shifts.