Analytic approach
Across the 3 cohorts, 122 CF Programs participated in the study (80 in Cohort 1, 30 in Cohort 2, & 12 in Cohort 3), which represented 88.4% of grant recipients. Programs in Cohorts 1 and 2 completed multiple yearly surveys, and 39 programs had more than one provider complete the survey for a given year. All analyses were performed at the level of the CF program and scores from multiple providers were aggregated within each program using the mean implementation score and the maximum number of years at the program across providers. Descriptive statistics were calculated for each cohort and compared across cohorts using chi-square tests of independence. To account for nesting of programs within years, a random intercept linear mixed effect model was used to estimate the total implementation score by cohort and year. To examine differences in implementation across programs and to identify predictors of implementation scores, we used a linear regression model with the following predictors: type of program (pediatric, adult, both), size of the program (small, medium, large), and years of experience working on the CF team. Cohort was included as a covariate. To examine differences in implementation over time, we used a random effect model to predict both initial implementation and change in implementation across time (i.e., interactions between predictors and year) using grant year, type of program, program size, and MHC years of experience as predictor variables. Random effects included the intercept and year. All analyses were performed using the lme4 v1.1-26 , Table one v0.13.0, andstats v4.0.3 R packages.