Measurement of colorectal cancer test use with medical claims data in a safety-net health system

BACKGROUND: Optimizing colorectal cancer (CRC) screening requires identification of unscreened individuals and tracking screening trends. A recent National Institutes of Health State of the Science Conference, "Enhancing Use and Quality of CRC Screening," cited a need for more population data sources for measurement of CRC screening, particularly for the medically underserved. Medical claims data (claims data) are created and maintained by many health systems to facilitate billing for services rendered and may be an efficient resource for identifying unscreened individuals. The aim of this study, conducted at a safety-net health system, was to determine whether CRC test use measured by claims data matches medical chart documentation. METHODS: The authors randomly selected 400 patients from a universe of 20,000 patients previously included in an analysis of CRC test use based on claims data 2002-2006 in Tarrant Co, TX. Claims data were compared with medical chart documentation by estimation of agreement and examination of test use over/underdocumentation. RESULTS: The authors found that agreement on test use was very good for fecal occult blood testing (κ = 0.83, 95% confidence interval: 0.75-0.90) and colonoscopy (κ = 0.91, 95% confidence interval: 0.85-0.96) and fair for sigmoidoscopy (κ = 0.39, 95% confidence interval: 0.28-0.49). Over- and underdocumentations of the 2 most commonly used CRC tests - colonoscopy and fecal occult blood testing - were rare. CONCLUSIONS: Use of claims data by health systems to measure CRC test use is a promising alternative to measuring CRC test use with medical chart review and may be used to identify unscreened patients for screening interventions and track screening trends over time.