Operational definitions of inequality, deprivation and vulnerability in social and environmental justice research

Purpose This study addresses the persistent conceptual ambiguity in defining and measuring social disparities, such as inequality, deprivation and vulnerability, which hinders effective social justice research and policy interventions. The aim of the present study is to propose a clear and precise conceptual framework to facilitate the standardized operationalization of these concepts across research and policy contexts. Design/methodology/approach An interdisciplinary literature review was undertaken, encompassing environmental studies, sociology, geography and related fields. The study examined and compared existing definitions, measurement methods and applications of inequality, deprivation and vulnerability. Variations in indicators, spatial scales and disciplinary approaches were systematically assessed. Insights were synthesized to propose coherent operational guidelines that accommodate diverse research contexts while maintaining conceptual clarity. Findings The analysis reveals persistent variability and interchangeability in the use of these core concepts, which undermines comparability across studies. A core set of conceptual domains and operational guidelines is proposed, highlighting how these concepts can be operationalized in ways that respect disciplinary, spatial and methodological contexts. These findings provide a foundation for more consistent measurement, guiding research-informed policy development and the improvement of social welfare systems. Originality/value The article contributes a theoretically grounded framework for clarifying social justice concepts, synthesizing divergent disciplinary indicators to provide practical guidance for researchers and policymakers, thereby strengthening the link between conceptual clarity and actionable social policy aimed at reducing social disparities.