Inclusion: Conceptualization and measurement

n the present research, we introduced a conceptual framework of inclusion and subsequently used this as a starting point to develop and validate a scale to measure perceptions of inclusion. Departing from existing work on inclusion and complementing this with theoretical insights from optimal distinctiveness theory and self-determination theory, we proposed that inclusion is a hierarchical two-dimensional concept consisting of perceptions of belonging and authenticity. In addition, we posed that in the process of inclusion, it is the group rather than the individual that has primary agency. From this conceptualization, we developed and validated the 16-item perceived group inclusion scale (PGIS). Data from two samples supported our proposed configuration of inclusion. In addition, the PGIS appeared to be a reliable measure of inclusion and was demonstrated to possess both nomological and predictive validity. Taken together, this research contributes to the conceptual refinement of the inclusion construct and offers researchers a reliable and valid tool to conduct future inclusion research.