Karin Zimmer is Professor of Empirical Educational Research at the University of Vechta, Germany. She holds a doctorate in psychology and has worked at various universities in Germany and Denmark, the IPN Leibniz Institute for Science and Mathematics Education (Kiel, Germany), the DIPF Leibniz Institute for Research and Information in Education (Frankfurt, Germany) and the OECD Education Directorate (Paris, France). Her current focus is on participatory research approaches and conducting systematic reviews on educational and public-health topics.Jan-Henning Ehm is Professor of Developmental and Educational Psychology with a focus on Early Childhood Education at Heidelberg University of Education. His work centers on cognitive and socio-emotional development in early childhood, with a particular emphasis on early literacy acquisition, school readiness, and the effectiveness of educational interventions. He is involved in applied research, regularly consults in early education contexts, and contributes to interdisciplinary projects aimed at improving quality in early learning environments.Susanne Kuger is Research Director at the German Youth Institute (DJI) and Professor of Empirical Social and Educational Research for Children and Adolescents at Ludwig-Maximilians-Universität Munich. Her research focuses on educational effectiveness in formal, non-formal and informal learning environments, with a particular interest in interaction quality, language development, and educational equity. She leads and contributes to large-scale longitudinal studies such as KiBS, ERiK, AID:A, and NEPS, and is a recognized expert in comparative survey methodology.Jan Lonnemann is Professor of Empirical Childhood Research at the University of Potsdam, Germany. He holds a doctorate in psychology and has worked at the DIPF Leibniz Institute for Research and Information in Education (Frankfurt am Main, Germany), at the Goethe University (Frankfurt am Main, Germany) and at the RWTH Aachen University (Germany). His current research interests include children's development of number, space and time concepts as well as interaction and participation in early education settings.Jolika Schulte is an information scientist and academic librarian. For many years, her work as a librarian focussed on teaching information and research skills. In her academic career she has focussed on methods of information retrieval and systematic review. She currently works as an academic librarian (Head of Acquisitions Department) at the Lippische Landesbibliothek in Detmold.Dominique Rauch is Professor of Psychology at Ludwigsburg University of Education. Her research focuses on disparities between children and adolescents with and without migration backgrounds, as well as reading diagnostics and support in multilingual contexts. She is particularly interested in school-based intervention research and the conditions for successful educational support for children with refugee experience. Dominique Rauch is actively involved in applied research and contributes to interdisciplinary projects aimed at promoting educational equity and improving outcomes for linguistically and culturally diverse student populations.Marcus Hasselhorn is Professor of Psychology and Director of the Department of Education and Human Development at the DIPF | Leibniz-Institute of Research and Information in Education in Frankfurt/Main. He was the founder chair (in 2008) of the Frankfurt Center for Research on Individual Development and Adaptive Education for Children at Risk (IDeA). From it’s start in 2013 till 2025 he also was the spokesman of the Leibniz Educational Research Network (LERN). His current research interests include learning disabilities and their identification and prevention as well as the challenges and potentials of children’s development in early education.

• Background.- Objectives.- Review methodology.- Information on the sources.- Map of Interventions (Research Question 1).- Effectiveness of the Interventions (Research Question 2).- Concluding remarks.- References.- Appendix.