Identifying In-Hospital Venous Thromboembolism (VTE): A Comparison of Claims-Based Approaches with the Rochester Epidemiology Project VTE Cohort

• Published in: Medical care Vol. 46; no. 2; pp. 127 - 132
• Main Authors: Leibson, Cynthia L., Needleman, Jack, Buerhaus, Peter, Heit, John A., Melton, L. Joseph, Naessens, James M., Bailey, Kent R., Petterson, Tanya M., Ransom, Jeanine E., Harris, Marcelline R.
• Format: Journal Article
• Language: English
• Published: United States Lippincott Williams & Wilkins 01-02-2008; Lippincott Williams & Wilkins, Inc; Lippincott Williams & Wilkins Ovid Technologies
• Subjects: Aged; Aged, 80 and over; Cohort Studies; Comparative analysis; Epidemiology; Estimate reliability; False negative errors; False positive errors; Female; Hospital administration; Hospital admissions; Hospitals; Hospitals, Group Practice - economics; Hospitals, Group Practice - standards; Hospitals, Group Practice - statistics & numerical data; Humans; Iatrogenic Disease - epidemiology; Insurance Claim Reporting - statistics & numerical data; International Classification of Diseases - statistics & numerical data; Male; Medical diagnosis; Medical Record Linkage; Medical records; Medicare; Middle Aged; Minnesota - epidemiology; Outcome Assessment (Health Care) - economics; Outcome Assessment (Health Care) - methods; Patient Admission - statistics & numerical data; Quality Indicators, Health Care; Reimbursement, Incentive; Risk Adjustment - methods; Risk Assessment; Sensitivity and Specificity; United States; Vein & artery diseases; Venous Thromboembolism - classification; Venous Thromboembolism - economics; Venous Thromboembolism - epidemiology; Venous Thromboembolism - etiology; Venous thrombosis; United States; Minnesota; Olmsted County Minnesota
• ISSN: 0025-7079; 1537-1948
• DOI: 10.1097/MLR.0b013e3181589b92

Background: Efforts to identify hospital-acquired complications from claims data by applying exclusion rules to discharge diagnosis codes exhibit low positive predictive value (PPV). The PPV improves when a variable is added to each secondary diagnosis to indicate whether the condition was "present-on-admission" (POA) or "hospital-acquired". Such indicator variables will soon be required for Medicare reimbursement. No estimates are available, however, of the proportion of hospital-acquired complications that are missed (sensitivity) using either exclusion rules or indicator variables. We estimated sensitivity, specificity, PPV, and negative predictive value (NPV) of claims-based approaches using the Rochester Epidemiology Project (REP) venous thromboembolism (VTE) cohort as a "gold standard." Methods: All inpatient encounters by Olmsted County, Minnesota, residents at Mayo Clinic-affiliated hospitals 1995-1998 constituted the at-risk- population. REP-identified hospital-acquired VTE consisted of all objectively-diagnosed VTE among County residents 1995-1998, whose onset of symptoms occurred during inpatient stays at these hospitals, as confirmed by detailed review of County residents' provider-linked medical records. Claims-based approaches used billing data from these hospitals. Results: Of 37,845 inpatient encounters, 98 had REP-identified hospital-acquired VTE; 47 (48%) were medical encounters. NPV and specificity were >99% for both claims-based approaches. Although indicator variables provided higher PPV (74%) compared with exclusion rules (35%), the sensitivity for exclusion rules was 74% compared with only 38% for indicator variables. Misclassification was greater for medical than surgical encounters. Conclusions: Utility and accuracy of claims data for identifying hospital-acquired conditions, including POA indicator variables, requires close attention be paid by clinicians and coders to what is being recorded.