Multi-component interventions and change in screening rates in primary care clinics in the Colorectal Cancer Control Program.

Colorectal cancer (CRC) screening has been shown to decrease CRC mortality. Implementation of evidence-based interventions (EBIs) increases CRC screening. The purpose of this analysis is to determine which combinations of EBIs or strategies led to increases in clinic-level screening rates among clinics participating in CDC's Colorectal Cancer Control Program (CRCCP). Data were collected from CRCCP clinics between 2015 and 2018 and the analysis was conducted in 2020. The outcome variable was the annual change in clinic level CRC screening rate in percentage points. We used first difference (FD) estimator of linear panel data regression model to estimate the associations of outcome with independent variables, which include different combinations of EBIs and intervention strategies. The study sample included 486 unique clinics with 1156 clinic years of total observations. The average baseline screening rate was 41 % with average annual increase of 4.6 percentage points. Only two out of six combinations of any two EBIs were associated with increases in screening rate (largest was 6.5 percentage points, P < 0.001). Any combinations involving three EBIs or all four EBIs were significantly associated with the outcome with largest increase of 7.2 percentage points (P < 0.001). All interventions involving 2-3 strategies led to increases in rate with largest increase associated with the combination of increasing community demand and access (6.1 percentage points, P < 0.001). Clinics implementing combinations of these EBIs, particularly those including three or more EBIs, often were more likely to have impact on screening rate change than those implementing none.