Electronic ordering systems have the potential to enhance the effective and efficient utilisation of pathology services. This study examined the influence of electronic ordering of pathology tests in four emergency departments on data entry times, a contributing factor to test turnaround time using failure time analysis. Data relating to tests ordered for 50,854 emergency department patients at four hospitals were analysed. The introduction of electronic test ordering significantly reduced turnaround time associated with laboratory data entry at the four hospitals, but there was significant variation between hospitals. Investigation of the impact of electronic ordering on efficiency of pathology services must take into account specific aspects of turnaround time measurement.