Psychometric properties of the Irritability and Dysregulation of Emotion Scale (TIDES-13) and Emotional Outburst Inventory (EMO-I) in a transdiagnostic sample of Turkish youth

Abstract Objective Irritability is a transdiagnostic phenomenon within the irritability-anger-aggression spectrum, but available measures often fail to capture its multifaceted nature. This study evaluated the psychometric properties and clinical utility of two new measures: the Emotional Outburst Inventory (EMO-I), assessing phasic irritability phenomenology, and the Irritability and Dysregulation of Emotion Scale (TIDES-13), designed as a multidimensional measure. Method In a clinical sample of 113 Turkish children and adolescents (54% males, the age mean of 11.80 (3.89) years), one parent completed the EMO-I, TIDES-13, Affective Reactivity Index (ARI), and several measures of psychopathology (T-DSM-IV-S, Revised Child Anxiety and Depression Scale [RCADS], and Strengths and Difficulties Questionnaire [SDQ]). Self-reports (n = 87) were obtained for the TIDES-13, ARI, RCADS, and SDQ. Exploratory factor analysis, internal consistency, intraclass correlation coefficient (ICC), convergent/incremental validity, and group comparisons were conducted. Results Factor analysis supported a unidimensional structure for the parent-report TIDES-13 and a two-factor solution for the self-report version. Both TIDES-13 versions showed excellent internal consistency (α = 0.97 for the parent and 0.93 for the self-report), with ICC = 0.45 for single and 0.62 average measures. The TIDES-13 demonstrated robust correlations with externalizing and internalizing symptoms ( r = 0.23–0.63) and superior incremental validity over ARI for predicting attention deficit hyperactivity disorder (ADHD) and conduct symptoms. The EMO-I dimensions (severity, frequency, duration, baseline irritability) were moderately intercorrelated and showed modest associations with psychopathology. The TIDES-13 accounted for significant unique variance in psychopathology beyond EMO-I, whereas the EMO-I showed limited incremental validity beyond ARI and TIDES-13. No significant diagnostic group differences were found on either measure. Conclusions The TIDES-13 is a psychometrically robust, transdiagnostic measure of irritability suitable for Turkish clinical settings. The EMO-I provides detailed phenomenology of emotional outbursts. Findings support the complementary use of TIDES-13 for assessing trait irritability and EMO-I for detailing episodic outbursts. Future studies using larger and longitudinal samples are warranted to further establish the developmental and clinical implications of these measures, especially considering the limitations of this study.