Development and Validation of the Criminal Aptitude Inventory (Urdu): A Comprehensive Assessment Across Convicted Prisoners and the General Population

Background: Criminal aptitude testing benefits police and other fields of law enforcement. Earlier literature lacked an Urdu-language scale for criminal aptitude. Objectives: The present study developed and validated a new scale to measure criminal aptitude in Urdu speakers. Methods: The development and validation of the Criminal Aptitude Inventory (CAI) unfolded across three distinct phases, involving a total of 1675 participants (51.34% women), including convicted prisoners (37.33%). In the initial phase, the CAI underwent development and preliminary validation through exploratory factor analysis (EFA). Subsequently, the second phase utilized Confirmatory Factor Analysis to further confirm the scale s validity. The third phase focused on analyzing the CAI s convergent and discriminant validity by investigating its relationship with antisocial personality disorder, morality, religiosity, and spirituality. Results: The results demonstrated high reliability and validity of the CAI, affirming its suitability for future applications. The final version of the scale comprises a single factor and consists of 36 items, each utilizing a 5-point Likert-type response format. Indicators such as Kaiser-Meyer-Olkin s values (0.984), Cronbach’s alpha (0.984), average item-total correlation (P 0.001), comparative fit index (0.936), Tucker-Lewis Index (0.932), Goodness of Fit Index (GFI=.939), root mean square error of approximation (RMSEA = 0.043), convergent validity with antisocial personality disorder (r = 0.458; P 0.01), and discriminant validity with morality (r = -0.396; P 0.01), religiosity (r = -.318; P 0.01), and spirituality (r = -.453; P 0.01) established the reliability and validity of the CAI. Conclusions: The dual-source data collection strategy employed in this study, drawing from both convicted prisoners and the general population, enhances and operationalizes the scale. This approach ensures its applicability across diverse Urdu-speaking communities in Pakistan and India.