Research suggests effective professional learning communities (PLCs) enhance teacher collaboration and student achievement. Some studies indicate that these communities also predict greater collective efficacy, while others suggest teacher efficacy is predictive of teachers working together. Although studies have identified effective,…

Purpose: The purpose of this paper is to conduct a critical review of the mediation studies published in the field of Human Resource Development (HRD) to discern if the study designs, the nature of data collection and the choice of statistical methods justify the causal claims made in those studies. Design/methodology/approach: This paper conducts…