Comparison of Critical Drug-Drug Interactions from the Department of Veteran Affairs to the Standard Reference Compendia

Abstract

Objectives: The purpose of this study is to compare the critical drug-drug interaction alerting software at the Department of Veteran Affairs with Hansten and Horn's drug analysis and management (DIAM) and Micromedex®. Methods: The Department of Veterans Affairs supplied a list of drug-drug interacting (DDI) pairs. Each pair was labled as significant or critical. The critical interactions were included in the study (n=1018). Two researchers inputed the interactions into Micromedex and looked up the interactions in Hansten and Horn's drug interactions analysis and management (DIAM). A Kappa statistic was used to calculate the agreement between the 2 researchers. Results: The researchers differed in the number of interactions found to be "contraindicated" or "major" in Micromedex and "avoid" or "usually aviod" in DIAM (researcher 1= 683, 330, respectively; researcher 2= 672,176, respectively) with a Kappa of 0.9 for Micromedex and 0.57 for DIAM. Conclusions: Our study suggests that there is a difference between the VA drug interaction alerting system, Micromedex ® and DIAM in regards to the way they list interactions and their method of rating the level of severity of the interactions. Also, there may be a difference in the way each researcher interprets the information.