Psychometric validation of the Muscle Dysmorphic Disorder Inventory (MDDI) among U.S. transgender men

Jason M Nagata; Emilio J Compte; F Hunter McGuire; Jason M Lavender; Stuart B Murray; Tiffany A Brown; Matthew R Capriotti; Annesa Flentje; Micah E Lubensky; Juno Obedin-Maliver; Mitchell R Lunn

doi:10.1016/j.bodyim.2022.05.001

Psychometric validation of the Muscle Dysmorphic Disorder Inventory (MDDI) among U.S. transgender men

Body Image. 2022 Sep:42:43-49. doi: 10.1016/j.bodyim.2022.05.001. Epub 2022 May 31.

Authors

Affiliations

¹ Department of Pediatrics, University of California, San Francisco, San Francisco, CA, USA. Electronic address: jason.nagata@ucsf.edu.
² Eating Behavior Research Center, School of Psychology, Universidad Adolfo Ibáñez, Santiago, Chile; Research Department, Comenzar de Nuevo Treatment Center, Monterrey, Mexico.
³ The Brown School, Washington University in St. Louis, St. Louis, MO, USA.
⁴ Military Cardiovascular Outcomes Research Program (MiCOR), Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD, USA; The Metis Foundation, San Antonio, TX, USA.
⁵ Department of Psychiatry and Behavioral Sciences, University of Southern California, Los Angeles, CA, USA.
⁶ Department of Psychological Sciences, Auburn University, Auburn, AL, USA.
⁷ Department of Psychology, San José State University, San Jose, CA, USA; The PRIDE Study/PRIDEnet, Stanford University School of Medicine, Stanford, CA, USA.
⁸ The PRIDE Study/PRIDEnet, Stanford University School of Medicine, Stanford, CA, USA; Department of Community Health Systems, University of California, San Francisco, San Francisco, CA, USA; Alliance Health Project, Department of Psychiatry and Behavioral Sciences, University of California, San Francisco, San Francisco, CA, USA.
⁹ The PRIDE Study/PRIDEnet, Stanford University School of Medicine, Stanford, CA, USA; Department of Community Health Systems, University of California, San Francisco, San Francisco, CA, USA.
¹⁰ The PRIDE Study/PRIDEnet, Stanford University School of Medicine, Stanford, CA, USA; Department of Obstetrics and Gynecology, Stanford University School of Medicine, Stanford, CA, USA; Department of Epidemiology and Population Health, Stanford University School of Medicine, Stanford, CA, USA.
¹¹ The PRIDE Study/PRIDEnet, Stanford University School of Medicine, Stanford, CA, USA; Department of Epidemiology and Population Health, Stanford University School of Medicine, Stanford, CA, USA; Division of Nephrology, Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA.

Abstract

Muscle dysmorphia (MD) is characterized by a pervasive belief or fear of insufficient muscularity and an elevated drive for muscularity, representing the pathological and extreme pursuit of muscularity. Psychometric properties of one of the most widely used measures of MD symptoms-the Muscle Dysmorphic Disorder Inventory (MDDI)-have yet to be evaluated in transgender men despite emerging evidence suggesting differential risk for MD symptoms in this population. In this study, we assessed the psychometric properties of the MDDI in a sample of 330 transgender men ages 18-67 years who participated in a large-scale national longitudinal cohort study of sexual and gender minority adults in the U.S. Using a two-step, split-sample approach, an initial exploratory factor analysis supported a three-factor structure and a subsequent confirmatory factor analysis of a re-specified three-factor model demonstrated good overall fit (χ²/df = 1.84, CFI =0.94, TLI =0.92, RMSEA =0.07 [90% CI =0.05,.09], SRMR =0.08). Moreover, results supported the internal consistency and convergent validity of the MDDI subscales in transgender men. Findings inform the use of the MDDI among transgender men and provide a foundation to support further work on the MDDI and MD symptoms among gender minority populations.

Keywords: Assessment; Gender minority; Muscle dysmorphia; Muscle dysmorphic disorder inventory; Transgender.

MeSH terms

Adolescent
Adult
Aged
Body Dysmorphic Disorders* / diagnosis
Body Dysmorphic Disorders* / epidemiology
Body Image / psychology
Humans
Longitudinal Studies
Male
Middle Aged
Muscles
Psychometrics
Reproducibility of Results
Surveys and Questionnaires
Transgender Persons*
Young Adult

Abstract

MeSH terms

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