School leadership effects revisited: a review of empirical studies guided by indirect-effect models

Abstract

Fourteen leadership effect studies that used indirect-effect models were quantitatively analysed to explore the most promising mediating variables. The results indicate that total effect sizes based on indirect-effect studies appear to be low, quite comparable to the results of some meta-analyses of direct-effect studies. As the earlier indirect-effect studies tended to include a broad range of mainly school organisational conditions as intermediary variables, more recent studies focus more sharply on instructional conditions. The results of the conceptual analysis and the quantitative research synthesis would seem to support conceptualising educational leadership as a detached and ‘lean’ kind of meta-control, which would make maximum use of the available substitutes and self-organisation offered by the school staff and school organisational structural provisions. The coupling of conceptual analysis and systematic review of studies driven by indirect-effect models provides a new perspective on leadership effectiveness.

Keywords:

• school leadership
• indirect-effect studies
• intermediate variables
• student achievement

Acknowledgements

The research published in this article was supported by a grant from the Knowledge Directorate of the Dutch Ministry of Education.

Notes on contributors

Dr. Maria Hendriks is an assistant professor at the Department of Educational Sciences at the University of Twente, the Netherlands. Her research focuses on school self-evaluation, quality evaluation and educational innovation. She has participated in many EU and OECD funded research projects. Currently she is working on meta-analyses and review studies in the area of school effectiveness.

Prof. Dr. Jaap Scheerens is Professor emeritus at the University of Twente, where he led the Department of Educational Organization and Management. He has been a project leader of numerous international research projects funded by the European Union, and a consultant for international organisations like OECD, UNESCO and the World Bank. His publications are in the areas of school management, decentralisation in education, school effectiveness, and educational evaluation and monitoring.

Notes

1. Converting from r to d (Borenstein et al. 2009, 48), is as follows:

$d=\frac{2r}{\sqrt{1-r^2}}$

2. Hattie presents effect sizes in terms of the standardised mean difference between experimental and control group, which are roughly twice the size of the correlation coefficient for low to medium effect sizes.

3. According to Cohen (1988), small effects are in the order of r= 0.10, medium effects r=0.30 and large effects r=0.50 or higher.

4. The complete overview of results, including direct, indirect and total effects for all replications is available in a set of tables that can be obtained from the authors.

5. This study showed some highly negative effects (−0.31, −0.18 and −0.16, respectively) and on the other hand more replications (6) than all other publications in the table.