Psychometric properties of the Conners’ 3-parent rating scale in a clinical sample of Iranian children

BACKGROUND: Attention-deficit/hyperactivity disorder (ADHD) is a prevalent neurodevelopmental disorder among children that significantly affects academic, social, and emotional functioning. Early diagnosis is essential, highlighting the need for reliable and valid screening tools. The Conners’ Rating Scale (CRS) is frequently used for ADHD assessment; however, the psychometric properties of the latest version, the Conners’ Parent Rating Scale-3 (Conners 3-P), have not yet been examined in Iranian clinical populations. METHODS: This study aims to evaluate the reliability and validity of the Conners’ 3-Parent Rating Scale Short Form (Conners 3-P(S)) in a clinical sample of Iranian children aged 6–12 years. The study involved 135 children, including 55 children diagnosed with ADHD and 80 typically developing children. ADHD diagnoses were confirmed via the Kiddie Schedule for Affective Disorders and Schizophrenia-Present and Lifetime Version (K-SADS-PL_5). Parents completed the Conners 3-P(S) and the ADHD Rating Scale-IV (ADHD-RS-IV). Reliability was evaluated through Cronbach’s alpha and test‒retest analysis, whereas validity was assessed via Exploratory Factor Analysis (EFA), convergent validity testing, and Receiver Operating Characteristic (ROC) analysis. RESULTS: The EFA identified seven factors, namely, inattention, hyperactivity, learning problems, aggression, parents’ negative attitudes, parents’ positive attitudes, and peer relations, accounting for 56.28% of the variance. The Conners 3-P(S) scale demonstrated strong internal consistency (Cronbach’s alpha = 0.94) and excellent test‒retest reliability (intraclass correlation coefficient (ICC) = 0.90). Convergent validity analysis revealed significant correlations between the Conners 3-P subscales and ADHD-RS-IV scores, particularly for hyperactivity (r = 0.638, p < 0.01). The ROC curve indicated high diagnostic accuracy (area under the curve (AUC) = 0.93), with a cutoff score of 28.50 achieving 93% sensitivity and 70% specificity. CONCLUSIONS: The Conners 3-P(S) is a reliable and valid tool for assessing ADHD symptoms in Iranian children. Its strong psychometric properties support its clinical utility in diagnosing and monitoring ADHD. Future research should investigate its applicability in broader populations. CLINICAL TRIAL REGISTRATION: Not applicable.