Variation in the incidence and timing of diagnosis of hospital-associated venous thromboembolism using linked administrative data.

Venous thromboembolism (VTE) is a potentially preventable adverse effect of hospitalisation. Inter-hospital variation in the incidence of hospital-associated VTE (HA-VTE) and timing of diagnosis (in-hospital or post-discharge) in New South Wales public hospitals were examined. Large variations in incidence (22% risk difference) and post-discharge diagnosis (115% odds difference) were evident after adjustment for case mix, which only explained 59% and 32% of inter-hospital variation respectively. The need for improved compliance with best practice guidelines is reinforced.