Computerized Drug Prescription Decision Support

Abstract

Drug prescription has to satisfy three quality criteria. Orders have to be adapted to the patient state, be compatible with all the other drugs of the prescription, and in compliance with the recommendations described in clinical practice guidelines (CPGs). Computer provider order entry systems (CPOEs) have been developed to secure drug orders and they address the first two criteria. Clinical decision support systems (CDSSs) have been developed to improve the implementation of CPGs and promote evidence-based medicine. This chapter first introduces the different medication errors. Then, the general architecture of CPOEs (user interface, drug database, interface with electronic medical records (EMRs) and inference engine) is presented. The main modalities of entering drug orders are described. Alert generation for contra-indications, or drug-drug interactions, are detailed. CDSSs are tools to provide patient-specific recommended treatments. They rely on a knowledge base embedding CPGs. The translation process of CPGs from their original narrative format to a structured formalized representation is described. The difficulty of text translation is emphasized and documentary tools such as GEM that help formalize guideline content are described. The main guideline representation formalisms, Arden Syntax, decision trees, EON and GLIF, are presented. Then, ways of operating CDSSs are described, from the totally automated alert-based mode, to various documentary approaches where the user navigates through a structured knowledge base. Finally, examples of clinical decision support systems currently routinely used are given.