Measurement Invariance and Psychometric Properties of the Self-Concealment Scale in Iran.

Background/Objectives: Self-concealment is associated with greater psychological distress and decreased help-seeking engagement. This study aimed to evaluate the psychometric properties and sex invariance of the Persian Self-Concealment Scale (SCS) in Iranian adults. Methods: Participants were recruited using convenience sampling and social media advertising, targeting adults aged 18 or older who could read and understand Persian. The valid sample comprised 644 adults. Exploratory factor analysis was performed to delineate the underlying structural dimensions, followed by confirmatory factor analysis (CFA). Multi-group CFA was used to evaluate the gender invariance. Results: A one-factor exploratory solution explained 48.83% of the variance, whereas parallel analysis suggested three factors, indicating some residual multidimensionality. The initial one-factor CFA showed poor fit (RMSEA = 0.114, CFI = 0.899, TLI = 0.871). A revised one-factor model that accounted for four localized item-pair residual associations showed improved fit in Sample 2 (RMSEA = 0.062, CFI = 0.974, TLI = 0.962, N = 322) and acceptable fit when applied without further respecification to the non-overlapping Sample 1 (N = 322) internal holdout (RMSEA = 0.078, CFI = 0.960). Internal consistency was high (α = 0.896; ω = 0.897), while correlations with depression, anxiety, and stress ranged from 0.35 to 0.37, providing moderate evidence of convergent validity. Gender invariance was partially supported. Conclusions: The Persian SCS shows promising but qualified psychometric performance for research use, pending independent replication and longitudinal validation.