Cody Abbey

Jun 8, 2024 | bmcpsychology.biomedcentral.com | Huan Wang |Andrew Rule |Min Wang |Cody Abbey |Manpreet Singh |Scott Rozelle | +1 more

Students were recruited from five schools in Shanghai using a stratified two-stage cluster sampling approach. In the first stage, cluster random sampling was used to select two primary schools and three middle schools in Shanghai. In the second stage, stratified sampling approach was applied to randomly select three classes for each grade from grade 4th to grades 8th.