Monitoring postoperative pulmonary embolisms in Australia--I. Variation between hospitals

Information on inter-hospital variation in clinical outcomes can be extracted from routinely collected morbidity data in Australia. Postoperative pulmonary embolism rates, one of seven clinical performance indicators now subject to review during Australian hospitals' quality accreditation surveys, is used as an example throughout. Using indirect statistical standardisation and Poisson models of random variation, we were able to identify five hospitals which recorded statistically significantly higher pulmonary embolism rates than average and three which recorded lower than expected rates. The application of these methods to all hospital outcome measures will assist in objectively monitoring the quality of patient care.