Validation of the Nine-Item Avoidant/Restrictive Food Intake Disorder Screen Among Transgender and Nonbinary Youth and Young Adults.

Abstract

The purpose of the study was to provide initial evidence for the internal consistency and convergent validity of the nine-item avoidant/restrictive food intake disorder screen (NIAS) in a sample of transgender and nonbinary (TGNB) youth and young adults. Returning patients at a Midwestern gender clinic (n=164) ages 12-23 completed the NIAS, sick, control, one stone, fat, food (SCOFF), patient health questionnaire 9 (PHQ-9), and generalized anxiety disorder 7 (GAD-7) during their clinic visit. Age, sex assigned at birth, gender identity, weight, and height were also collected. Confirmatory factor analysis was used to establish the hypothesized three-factor structure of the NIAS in this sample. Relationships between the NIAS subscales and anthropometric data, SCOFF, PHQ-9, GAD-7, and sex assigned at birth were explored for convergent and divergent validity, and proposed screening cutoff scores were used to identify the prevalence of likely avoidant/restrictive food intake disorder (ARFID) in this population. The three-factor structure of the NIAS was an excellent fit to the current data. Approximately one in five (22%) of the participants screened positive for ARFID. Approximately one in four participants scored above the picky eating (27.4%) or appetite (23.9%) cutoffs. Assigned female at birth participants scored significantly higher on the NIAS-Total, Appetite, and Fear subscales than those assigned male at birth. NIAS-Total was significantly related to all convergent validity variables other than age, with a moderate-strong correlation with other symptom screeners (SCOFF, PHQ-9, GAD-7), and a small negative correlation with body mass index percentile. Evidence supports the NIAS as a valid measure to screen for ARFID among TGNB youth and young adults.