Testing for prostate and colorectal cancer: comparison of self-report and medical record audit

Abstract

Background. Self-reported data are often used to determine cancer screening test utilization, but self-report may be inaccurate. Methods. We interviewed members of three health maintenance organizations and reviewed their medical records for information on digital rectal exam (DRE), prostate-specific antigen (PSA) test, fecal occult blood test (FOBT), sigmoidoscopy, and colonoscopy (response rate 65%). We calculated the sensitivity, specificity, concordance, and kappa statistic to compare the two sources for black men ( n = 363), white and other men ( n = 847), and women ( n = 920) by study location. Results. For DRE, FOBT, sigmoidoscopy, and colonoscopy, testing rates determined by self-report were higher than those in medical records. Kappa statistics showed fair to good agreement (0.40–0.80) for PSA, sigmoidoscopy, and colonoscopy among most subgroups. For DRE and FOBT, the agreement was poor except among participants from one HMO. Sensitivity was ≥80% for sigmoidoscopy among most subgroups, and ≥85% for endoscopy (sigmoidoscopy and colonoscopy), >75% for DRE, and ≥63% for PSA among all subgroups. Specificity exceeded 80% for FOBT and colonoscopy among all subgroups. Agreement was lower among older age groups. For all tests, agreement was poor between the reasons for testing. Conclusion. Overreporting for some cancer tests should be considered when using self-reported data to evaluate progress towards reaching national goals for prevention behaviors.