In this study we examined the impact of an Electronic Medical Record (EMR) on repeat test rates (i.e., the same test ordered within a specified window of time) for a commonly ordered set of laboratory tests; Electrolytes, Urea, Creatinine [EUC], Full Blood Counts [FBC] and Liver Function Tests [LFT]. The results point to the potential that timely, evidence-based electronic decision support features can have on the efficiency and effectiveness of the pathology laboratory process and its contribution to quality patient care.