Systematic reviews on in-service training effectiveness. A prior comparative analysis of the used terms

The professional development of teachers has a definite impact on the improvement of the entire educational system (OECD, 2018; Darling-Hammond, 2017). For this reason, the main international organization - OECD (2013 ), European Commission (2012 ) - ask countries to establish feedback and accountability procedures for in-service training (ITT), for the ‘process by which teachers engage in further education or training to refresh or upgrade their professional knowledge, skills and practices in the course of their employment’ (UNESCO, 2019). Researchers state that here are numerous factors to be considered in carrying out this work: the type and quality of training, school climate, students’ skills, knowledge domain, etc. (Lipowsky & Rzejak, 2015). After a brief presentation of how the most recent systematic reviews on the topic have been conducted (Filges et al, 2019; Egert et al, 2018; Kalinowski et al., 2019), this article presents the results of a study on the terms and constructs in use in the context of the researches into in-service teacher/continuing professional training, impact/effect, and programs/instructions. The data and information collected offer a comparative analysis (Esser & Hanitzsch, 2012), based on systematic reviews (Polanin et al., 2019) and a meta-analysis, useful for setting up further meta-analytical investigations on the topic especially in terms of the disambiguation of terms and the narrowing of the field. The training of in-service teachers in many countries has been made compulsory and structural and is conceived as an opportunity for growth and professional development for the entire school community, and a strategic and functional logic for improving the quality of the school system (Perla, 2019). However, ministries of education do not yet have a univocal model and shared procedures capable of describing and analysing the impact that the training provided has in the terms set out in the European Commission (2020): output - results achieved immediately, i.e. increase in skills- focus subject to training; outcome - wider benefits for involved teachers - improvement of teaching practices of teachers involved in training; outreach - effects on the institutional and social context of the school where and of the territory within which the teachers involved in the training.