Regional Variations of Colorectal Cancer Screening

Introduction

Early detection of colorectal cancers (CRC) is an effective way to reduce mortality, however, CRC screening rates remain low. Studies suggest certain population subgroups are less likely to undergo CRC screening as recommended by guidelines. In this study, we examined factors contributing to CRC screening and identified areas with low CRC screening rates among members in a commercial health plan, accounting for known attributes.

Methods

Insurance claims data for 2009-13 were included in the study. Members without CRC and eligible for screening were identified, and procedure codes for fecal occult blood testing, sigmoidoscopy, and colonoscopy were used to confirm if members underwent screening. Members’ residential zipcodes were used to derive socioeconomic status information from Census. Factors contributing to CRC screening were first identified in logistic models, and further included in models to investigate areas where unaccountable low screening rates occurred.

Results

Results from logistic models indicate members with attributes of age>=65 (OR=1.44; 1-42-1.47); females (OR=1.24; 1.22-1.25), non-White race (OR=1.04; 1.02-1.06), non-Hispanic origin (OR=1.09; 1.06-1.12), less than college education (OR=1.10; 1.07-1.12), lower median household income (OR=1.29; 1.27-1.32), and living in rural areas (OR=1.09; 1.07-1.10) are associated with CRC screening noncompliance. After controlling for known attributes, areas identified with unaccountable low screening rates seem to cluster in the Midwest region.

Conclusions

Results from this study identify areas with low CRC screening compliance, after accounting for known attributes. Other healthcare system factors including provider counseling and public awareness may help explain such regional variations to target intervention.