Small Area Estimation of PSA Testing in US States and Counties

In 2012, the US Preventive Services Task Force recommended against prostate cancer screening using the PSA test for all age groups. In 2018, the US Preventive Services Task Force'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 to 69. Limited reliable county-level prostate cancer screening data are available for cancer surveillance purposes.

Utilizing data from the National Health Interview Survey (NHIS) and Behavioral Risk Factor Surveillance System (BRFSS) collected in 2012 to 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.

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

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

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