Validation of the Executive Functioning Scale (EFS) in Children With Neurodevelopmental Disorders and Their Typically Developing Peers: Psychometric Properties, Factor Structure and Measurement Invariance.

Objective: The current study was aimed at translating and validating the Persian version of the 52-item Executive Functioning Scale (EFS) for Iranian children.

Methods: The Persian EFS was administered online to a total of 600 Iranian children aged 2-17 years and their parents (48 with autism spectrum disorder, 162 with other neurodevelopmental/functional disorders and 390 typically developing). Construct validity was evaluated via confirmatory factor analysis (CFA) and exploratory structural equation modelling (ESEM) using the weighted least squares estimator. Four competing models were compared: a first-order six-factor model, a higher order model, a bifactor model and a six-factor ESEM model with target rotation. Measurement invariance across gender and age was tested. Reliability was assessed using Cronbach's α, McDonald's ω and 3-week test-retest intraclass correlations. Convergent and discriminant validity were examined through composite reliability (CR), average variance extracted (AVE) and correlations with the Behaviour Rating Inventory of Executive Function (BRIEF).

Results: The six-factor ESEM model provided the best fit (CFI = 0.974; TLI = 0.951; RMSEA = 0.059; WRMR = 0.717), outperforming the first-order (CFI = 0.903; TLI = 0.897) and bifactor solutions (CFI = 0.947; TLI = 0.926). Full configural, metric and scalar invariance held across gender and age (ΔCFI < 0.01). Subscale internal consistencies ranged from α = 0.70 to 0.84 and ω = 0.71 to 0.84; test-retest ICCs exceeded 0.80 for all scales. CR values exceeded 0.79, AVE values ranged from 0.41 to 0.56 and EFS-BRIEF correlations supported convergent and discriminant validity.

Conclusions: The Persian EFS demonstrates robust factorial validity, measurement invariance, reliability and convergent/discriminant validity in Iranian samples.