Identifying venous thromboembolism and major bleeding in emergency room discharges using administrative data

•We assessed the CIHI-NACRS database used for ER encounters in Canada.•Assessment was done after adopting the ICD-10CM system.•Codes for VTE have moderate predictive ability for identifying DVT and PE.•Codes for major bleeding have good ability for identifying major bleeding events.•CIHI-NACRS codes for major bleeding are appropriate for research use.

BackgroundAdministrative data can be used to identify venous thromboembolism (VTE) and major bleeding (MB) events. However, the validity of this data in emergency room discharge records in Canada is unknown.MethodsWe conducted a single-institution retrospective chart re-abstraction study in London, Canada. We identified all adult patients with a VTE or MB code included in the mandatory Canadian Institute for Health Information National Ambulatory Care Reporting System seen at our institution between July 2002 and March 2014. VTE was defined using the International Classification of Diseases, 10th revision (ICD-10CM) codes for deep venous thrombosis (DVT), and pulmonary embolism (PE) whereas MB was defined using codes for intracerebral hemorrhage, subarachnoid hemorrhage, subdural hemorrhage, upper, and lower gastrointestinal bleeding. A random sample of 50 patients was obtained for each condition. Two abstractors independently conducted blinded diagnostic adjudication using standard criteria. Agreement was calculated using kappa statistics. Positive predictive values were calculated for VTE, MB and each diagnosis.ResultsOverall, ICD-10CM codes demonstrated very good ability to identify major bleeding events (PPV 88%). Diagnostic codes performed particularly well for all intracranial and lower gastrointestinal bleeds. In contrast, ICD-10CM codes for VTE had moderate ability (PPV 49%). Diagnostic codes for PE performed better than those for DVT.ConclusionSingle ICD-10CM codes for venous thromboembolism have moderate predictive value for identifying DVT and PE in emergency room discharges. In contrast, codes for MB events have very good ability and it would be adequate to use them for research purposes.