P-327: Differential item functioning in the mSCOFF: unequal screening for diabetes-specific disordered eating behaviors by race, sex, and HbA1c
V Ellison, K Berlin, S Newman, K Desai, P Logan, M Keenan-Pfeiffer, J Cook, K Semenkovich, M Bowden, K Sumpter, A EddingtonAbstract
Introduction
Disordered eating behaviors (DEBs) are common among youth with type 1 diabetes (T1D) and are associated with poorer glycemic control, diabetes complications, and increased morbidity. The modified SCOFF (mSCOFF) is a recommended brief screener for DEBs in T1D; however, its measurement equivalence across demographic and clinical groups has not been evaluated.
Objectives
1) to assess the factor structure and model fit of the mSCOFF screener among Black and White youth with T1D and 2) to assess systematic item bias in the mSCOFF as a function of HbA1c, race, and gender.
Methods
Participants included 130 youth with T1D (54% female, 57% Black; mean HbA1c = 10.89%, SD = 2.25) attending a pediatric endocrinology clinic. Confirmatory factor analysis (CFA) evaluated the factor structure. Item response theory differential item functioning (DIF) analyses examined whether item responses varied by race, sex assigned at birth, and HbA1c after controlling for underlying DEB severity. The impact of DIF on one-item and two-item screening classifications was also examined.
Results
A one-factor CFA demonstrated acceptable model fit (χ2 = 6.23, df = 5, CFI = .986, RMSEA = .043). All five mSCOFF items demonstrated meaningful non-uniform DIF, indicating item functioning varied by race, sex assigned at birth, and HbA1c despite equivalent DEB severity. These differences resulted in inequitable screening classifications under both screening rules, with probabilities of screening positive varying by demographic and clinical characteristics rather than DEB severity alone.
Conclusions
The mSCOFF demonstrated substantial measurement inequities across race, sex assigned at birth, and HbA1c among youth with T1D. Standard screening cutoffs may over-identify some groups while under-identifying others. Findings highlight the need for equitable screening approaches to improve identification of DEBs and appropriate referral among diverse youth with T1D.