Identifying in-hospital venous thromboembolism (VTE): a comparison of claims-based approaches with the Rochester Epidemiology Project VTE cohort.

Abstract

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.

• Authors: Cynthia L Leibson, Jack Needleman, Peter Buerhaus, John A Heit, L Joseph Melton 3rd, James M Naessens, Kent R Bailey, Tanya M Petterson, Jeanine E Ransom, Marcelline R Harris
• Journal: Medical care (Med Care) Vol. 46 Issue 2 Pg. 127-32 (Feb 2008) ISSN: 0025-7079 [Print] United States
• PMID: 18219240 (Publication Type: Comparative Study, Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)

Topics

• Aged
• Aged, 80 and over
• Cohort Studies
• Female
• Hospitals, Group Practice (economics, standards, statistics & numerical data)
• Humans
• Iatrogenic Disease (epidemiology)
• Insurance Claim Reporting (statistics & numerical data)
• International Classification of Diseases (statistics & numerical data)
• Male
• Medical Record Linkage
• Medicare
• Middle Aged
• Minnesota (epidemiology)
• Outcome Assessment, Health Care (economics, methods)
• Patient Admission (statistics & numerical data)
• Quality Indicators, Health Care
• Reimbursement, Incentive
• Risk Adjustment (methods)
• Risk Assessment
• Sensitivity and Specificity
• United States
• Venous Thromboembolism (classification, economics, epidemiology, etiology)