Chronic care facility stay has been shown to be an independent risk factor for venous thromboembolism. Review of the literature, however, reveals a paucity of data addressing the issue of venous thromboembolism in nursing home residents. The purpose of this study was to determine the incidence of venous thromboembolic events among nursing home residents. A retrospective cohort study was derived from data compiled in the State of Kansas Minimum Data Set (MDS) for nursing home residents from July 1, 1997 to July 1, 1998. A total of 18,661 residents (median age, 85 years, 74% female, 95% white) satisfied the study criteria. The outcome measures of the primary endpoint-development of a venous thromboembolic event (VTE)-were obtained from the MDS quarterly health assessments and the Medicare ICD-9 codes. We determined the incidence of VTE among nursing home residents as 1.30 events per 100 person-years of observation.