Study design
The design is a cluster randomized controlled trial with sub-district as the unit of randomization. There are mainly three reasons for choosing cluster randomization as the method of randomization: (1) CBR was provided as group intervention at community healthcare, which exclude the possibility of randomization at individual level; (2) randomization at sub-district will be more economical and less time-consuming for both provider and participants; (3) The acceptability will be maximized, and the possibility of contamination could be minimized if all participants in a sub-district are allocated to either intervention or control arms. The study flow chart is presented in Fig. 
CRISC flow chart