Statistical Analysis
weight loss
Data analysis was performed from March to June 2022. The study statisticians (E.A.F. and B.H.) were blinded to group assignment when completing all analyses. Descriptive statistics were used to present baseline characteristics, and independent Subanalyses were also conducted to examine 12-month weight loss in cohort 1 (before COVID-19) and cohort 2 (after COVID-19 onset). The model used to compare weight change between treatment conditions was modified to examine differences in weight change between cohorts. Rather than group, time, and group-by-time interaction effects, this model contained cohort, time, and group-by-cohort effects for both treatment groups combined. Covariates were the same as in the primary weight loss model. All analyses were conducted as planned in our original analysis plan, except for the analysis by cohort, which was conducted before unblinding of the data and after analysis of the initial results to compare weight loss among participants in the study before and during the COVID-19 pandemic.Sample size calculations have been described elsewhere.