An event monitor is a clinical decision support system that comprises a set of rules for evaluating the information in a database for the purpose of, if necessary, generating messages about the information to be sent to those who may need to act upon it.
A common and important use in the healthcare setting is the detection of potential adverse drug events. For example, when a clinician enters a medication order for a particular patient, a rule is triggered; the rule queries the database for that patient’s known allergies, and if an allergy to that or a similar medication is discovered, a message will be sent to the clinician, informing him or her of the allergy.
A simple model has three components: an event, a condition, and an action.1 In the example above, the event is the entry of the medication order, the condition is the evaluation of the patient’s information to determine if an allergy exists, and the action is the message sent to the clinician if an allergy is discovered. Figure 1 shows a diagram of an event monitor adapted from Hripcsak et al. An event, such as a clinician order entry, triggers a rule, which queries the database. If the condition of the rule is satisfied, the action (for example, a message to the clinician) is executed. The action’s operations on the database are also events that can trigger rules without external input.
- Hripcsak G, Clayton PD, Jenders RA, Cimino JJ, Johnson SB. (1996). Design of a Clinical Event Monitor. Computers and Biomedical Research 29:194-221.
- Handler SM, Altman RL, Perera S, Hanlon JT, Studenski SA, Bost JE, Saul MI, Fridsma DB. (2007). A Systematic Review of the Performance Characteristics of Clinical Event Monitor Signals Used to Detect Adverse Drug Events in the Hospital Setting. Journal of the American Medical Informatics Association 14:4.
- Seger AC, Jha AK, Bates DW. (2007). Adverse Drug Event Detection in a Community Hospital Utilising Computerised Medication and Laboratory Data. Drug Safety 30:9.