1 School of Psychology and Sport Science, Anglia Ruskin University, Cambridge, United Kingdom; Centre for Psychological Medicine, Perdana University, Kuala Lumpur, Malaysia. Electronic address: viren.swami@aru.ac.uk.
2 Department of Psychoeducation and Psychology, Université du Québec en Outaouais, Saint-Jérôme, Canada; Cyberpsychology Laboratory, Department of Psychoeducation and Psychology, Université du Québec en Outaouais, Saint-Jérôme, Canada; Substantive-Methodological Synergy Research Laboratory, Department of Psychology, Concordia University, Montreal, Canada.
3 Substantive-Methodological Synergy Research Laboratory, Department of Psychology, Concordia University, Montreal, Canada.

Traditionally, assessments of factor validity of body image instruments have relied on exploratory or confirmatory factor analysis. However, the emergence of exploratory structural equation modeling (ESEM), a resurgence of interest in bifactor models, and the ability to combine both models (bifactor-ESEM) is beginning to shape the future of body image research. For these analytic approaches to truly advance body image research, scholars will need to have a deep understanding of their use and application. To facilitate such understanding, we describe ESEM and bifactor-ESEM models for body image researchers and provide them with the tools they need to apply these methods in their own work. Specifically, we provide an overview of ESEM and bifactor-ESEM models, and describe their broad applicability to body image research. Next, we describe how ESEM and bifactor models can be used and, using an existing dataset of responses to the Acceptance of Cosmetic Surgery Scale, demonstrate how ESEM and bifactor-ESEM models can be deployed. To facilitate wider application of these ideas, we provide our Mplus syntax (inputs) in Supplementary Materials. Through this manuscript, we hope to assist researchers to better understand the strengths ESEM and bifactor models, and to use these approaches in their own work.