Published in the International Journal of Medical Informatics, the following systematic review assess the effectiveness of various interruptive medication prescribing alerts to change prescriber behavior and/or to improve patient outcomes in hospital computerized provider order entry (CPOE) systems. The greatest volume of evidence relates to three alert categories: drug-condition, drug-drug and corollary order alerts. While the majority of alert categories were shown to improve outcomes in some studies, there were also many cases where outcomes did not improve.