School-based social capital: The missing link between schools' socioeconomic composition and collective teacher efficacy

•Links between school SES, school-based social capital, and CTE are investigated•Data of 183 schools are studied using multilevel structural equation modeling.•Effects of school SES on CTE are mediated by school-based social capital.

This study investigates whether the established association between school socioeconomic composition and collective teacher efficacy (CTE) is possibly mediated by teacher staffs' perceptions of school-based social capital. For this purpose, data from 183 primary schools in Flanders (Belgium) gathered between 2006 and 2008 are examined by means of multilevel structural equation modeling (MSEM). The findings indicate that the relationship between school socioeconomic composition and CTE can indeed be explained by the level of school-based social capital as perceived by the teacher staff, even when school prior achievement, school ethnic composition, and school size are controlled.