Small area estimation of prostate-specific antigen testing in U.S. states and counties.

Background: In 2012, the U.S. Preventive Services Task Force (USPSTF) recommended against prostate cancer screening using the prostate-specific antigen (PSA) test for all age groups. In 2018 the USPSTF's recommendation shifted from a "D" (not recommended) to a "C" (selectively offering PSA-based screening based on professional judgment and patient preferences) in men ages 55-69. Limited reliable county-level prostate cancer screening data is available for cancer surveillance purposes.

Methods: Utilizing data from the National Health Interview Survey (NHIS) and Behavioral Risk Factor Surveillance System (BRFSS) collected in 2012-2019, state- and county-level small area models were developed for estimating PSA testing. Model diagnosis, internal validation, and external validation examining associations of PSA testing and prostate cancer incidence were conducted.

Results: Model-based estimates of PSA testing rate were produced for all U.S. states and 3,142 counties for two data periods: 2012-2016 and 2018-2019. Geographic variations across counties were demonstrated through maps. Moderate positive correlations between PSA-based screening and prostate cancer incidence were observed, for example, the state-level weighted Pearson's correlation coefficients were 0.5025 (p-value=0.0002) and 0.3691 (p-value=0.0077) for 2012-2016 and 2018-2019, respectively.

Conclusions: These modeled estimates showed improved precision and adjusted for the differences between BRFSS and NHIS. The approach of combining NHIS and BRFSS utilized strengths of the larger sample size of BRFSS and generally higher response rates and better household coverage from the NHIS.

Impact: The resulting small area estimates offer a valuable resource for the cancer surveillance community, aiding in targeted interventions, decision-making, and further research endeavors.