School-based social capital: The missing link between schools' socioeconomic composition and collective teacher efficacy Barbara Belfi a, * , Sarah Gielen a , Bieke De Fraine a , Karine Verschueren b , Chlo  e Meredith a a Center for Educational Effectiveness and Evaluation, Katholieke Universiteit Leuven, Dekenstraat 2, B-3000 Leuven, Belgium b Center for School Psychology, Katholieke Universiteit Leuven, Tiensestraat 102, B-3000 Leuven, Belgium highlights  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. article info Article history: Received 7 August 2013 Received in revised form 1 September 2014 Accepted 5 September 2014 Available online Keywords: Collective teacher efficacy (CTE) School socioeconomic composition School-based social capital Primary education Multilevel structural equation modeling (MSEM) abstract 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. © 2014 Elsevier Ltd. All rights reserved. 1. Introduction Ever since the famous 1966 Coleman report concluded that “the social composition of the student body is more highly related to achievement, independent of the student's own social background, than is any school factor” (Coleman et al., 1966, p. 325), school socioeconomic composition has been a popular research topic in the field of educational effectiveness research (EER; Hattie, 2002). This topic has also been of interest to politicians around the world who fear that large proportions of socioeconomically disadvan- taged students in schools will have a detrimental effect on the educational trajectories of all students attending such schools. Particularly in Flanders, the Dutch-speaking part of Belgium, where socioeconomic segregation in schools is very high as compared to other Western countries, disparities in school socioeconomic composition have been a major cause of concern (Jacobs, Rea, & Teney, 2009; OECD, 2010). The socioeconomic composition of pri- mary schools is believed to be particularly important for student achievement, as compared to the socioeconomic composition of secondary schools and schools for higher education, as primary school entrance introduces most children to a more diverse social system for the first time in their lives. Until that point, children spend most of their time within narrow family and community environments, which are often socially homogenous (Benner & Crosnoe, 2011). From both a practical and policy perspective, it is important to learn more about those specific characteristics of so- cioeconomically disadvantaged primary schools that are related to student achievement and are under the control of national educational policy or local school management. One such school characteristic is collective teacher efficacy (CTE). CTE refers to teachers' collective perception that teachers in a given school make an educational difference for their students over and above the * Corresponding author. Tel.: þ32 16 325747; fax: þ32 16 325859. E-mail addresses: barbara.belfi@ppw.kuleuven.be (B. Belfi), sarah.gielen@ppw. kuleuven.be (S. Gielen), bieke.defraine@ppw.kuleuven.be (B. De Fraine), karine. verschueren@ppw.kuleuven.be (K. Verschueren), chloe.meredith@ppw.kuleuven. be (C. Meredith). Contents lists available at ScienceDirect Teaching and Teacher Education journal homepage: www.elsevier.com/locate/tate http://dx.doi.org/10.1016/j.tate.2014.09.001 0742-051X/© 2014 Elsevier Ltd. All rights reserved. Teaching and Teacher Education 45 (2015) 33e44