Same or different? Eating disturbances across demographics and identities in adolescents

Disordered eating can emerge for various reasons among adolescents. Clinical evidence has persistently documented differences in adolescent eating disorder across demographics and identities. However, much of this research has overlooked the potential for differential item functioning (DIF), which suggests that eating-related items may not be understood or relevant equally across different identity groups. This measurement issue may lead to biased conclusions about group differences and diagnostic biases at the individual level. I formally tested the measurement properties of eating-related items (worry about weight gain, weight control, self-worth related to weight, and binge eating) using data from the Adolescent Brain Cognitive Development (ABCD) study (N = 9, 914 participants, yielding 33,913 cases across waves and informants, ages 10–14) across identities and demographics (i.e., children’s age, race/ethnicity, gender, sexual orientation, time since baseline, family socioeconomic status, ΔBMIp95, and rater). Using moderated nonlinear factor analysis, I identified sources of differential item functioning and conducted valid group comparisons with bias-corrected scores. Adolescents responded to body image items differently as a function of their identity and demographics leading to DIF. Most group differences (i.e., age, gender, race/ethnicity, sexual orientation) were underestimated due to measurement biases, except for rater differences being exaggerated. Bias-corrected group comparison revealed substantial heterogeneity across identities and demographics, with marginalized individuals reporting higher disordered eating (e.g., girl, transgender and gender nonbinary, nonheterosexuality, or Hispanic youth). Gender nonconforming or Black youth showed lower eating disturbance. Consistent with prior research, older age and ΔBMIp95 (deviation from the 95th percentile BMI for age and sex) were associated with more severe eating disturbances. Our results thus highlight the urgent need for more inclusive and culturally sensitive research approaches.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Psychology

Grantor

University of Illinois Urbana-Champaign

Year dc:date

2025

Author dc:creator

• Xu, Yang

Contributors dc:contributor

• Briley, D. A.

• Adolescent Eating Disorder
• Identities
• Differential Item Functioning

Statement dc:rights

• Copyright 2025 Yang Xu

Language dc:language

en, eng

Handle dc:identifier

https://hdl.handle.net/2142/129645

OAI record oai:identifier

https://www.ideals.illinois.edu/oai-pmh?verb=GetRecord&metadataPrefix=etdms&identifier=oai%3Awww.ideals.illinois.edu%3A2142%2F129645