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 > or = 80% for sigmoidoscopy among most subgroups, and > or = 85% for endoscopy (sigmoidoscopy and colonoscopy), >75% for DRE, and > or = 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.