Strengthening Validity Evidence of Multidimensional Personality Inventory (MDPI) Through Convergent-Discriminant Validity and Simulated Contrasted Group Method

Abstract

A multidimensional personality inventory (MDPI) was initially devised in 2013 (Zeb, 2013) to provide a culturally and religiously relevant personality assessment by including the Islamic personality philosophy. For the said purpose, four subscales were proposed: religiosity, psychopathology, mental health, and optimism. The validity of MDPI was established through a factor analytic approach (Zeb et al., 2013). To further enhance the validity of the inventory, the present study was proposed, which included two validity studies of M.D.P.I. Study one established MDPI's convergent and discriminant evidence by correlating it with scales. Results revealed that the tests measuring the same construct were significantly positively correlated. In contrast, the ones that differed from each other yielded negative or non-significant correlations, proving the construct validity of MDPI. The second study used a simulated contrasted group approach, which showed significant differences between the contrasted groups on the measured construct. The present study boosted confidence in the psychometric properties of MDPI and answered the shortcomings mentioned in the development phase of MDPI.