Clinical Epidemiology (Apr 2023)
Positive Predictive Value of Non-Traumatic Bleeding Diagnoses in the Danish National Patient Register
Abstract
Maja Thaarup,1 Peter Brønnum Nielsen,1,2 Anne Estrup Olesen,3,4 Maria Bitsch Poulsen,4,5 Torben Bjerregaard Larsen,1,2 Felix Wittström,3,6 Thure Filskov Overvad2,3 1Department of Cardiology, Aalborg University Hospital, Aalborg, Denmark; 2Aalborg Thrombosis Research Unit, Department of Clinical Medicine, Aalborg University, Aalborg, Denmark; 3Department of Clinical Pharmacology, Aalborg University Hospital, Aalborg, Denmark; 4Department of Clinical Medicine, Aalborg University, Aalborg, Denmark; 5Mech-Sense, Department of Gastroenterology & Hepatology, Aalborg University Hospital, Aalborg, Denmark; 6Department of Medicine Solna, Centre for Pharmacoepidemiology, Karolinska Institutet, Stockholm, SwedenCorrespondence: Thure Filskov Overvad, Aalborg University Hospital, Hobrovej 18-22, Aalborg, 9100, Denmark, Tel +45 51 55 53 55, Email [email protected]: The majority of bleeding diagnoses in the Danish National Patient Registry have not been validated despite extensive use in epidemiological research. Therefore, we examined the positive predictive value (PPV) of non-traumatic bleeding diagnoses in the Danish National Patient Registry.Study Design: Population-based validation study.Patients and Methods: Based on a manual review of electronic medical records, we estimated the PPV of diagnostic coding (International Classification of Diseases, Tenth Revision (ICD‐10)) for non-traumatic bleeding for all patients ≥ 65 years of age with any hospital contact in the North Denmark Region during March–December 2019 as registered in the Danish National Patient Registry. We calculated PPVs and associated 95% confidence intervals (CI) for non-traumatic bleeding diagnoses overall and stratified according to primary or secondary diagnosis, and according to major anatomical sites.Results: A total of 907 electronic medical records were available for review. The population mean age was 79.33 years (standard deviation (SD)=7.73) and 57.6% were males. Primary bleeding diagnoses accounted for 766 of the records and 141 were secondary bleeding diagnoses. The overall PPV for bleeding diagnoses was 94.0% (95% CI: 92.3– 95.4). The PPV was 98.7% (95% CI: 97.6– 99.3) for the primary diagnoses and 68.8% (95% CI: 60.7– 75.9) for the secondary diagnoses. When stratified according to subgroups of major anatomical sites, the PPVs ranged between 94.1% and 100% for the primary diagnoses, and between 53.8% and 100% for secondary diagnoses.Conclusion: The overall validity of non-traumatic bleeding diagnoses in the Danish National Patient Registry is high and considered acceptable for epidemiological research. However, PPVs were substantially higher for primary than for secondary diagnosis.Keywords: bleeding, epidemiology, validity, register-based research
