Abstract

Although the core belief construct is central in A. T. Beck's cognitive theory, little empirical research has been conducted to date to establish its psychometric properties as well as the way it explains manifestations of psychopathology. The aims of this study were to develop and provide the first evidence of validity and reliability of a new measure of core beliefs that quantifies negative core beliefs about the self (nCB-S) and negative core beliefs about others (nCB-O). Results indicated that this measure has adequate internal consistency and test–retest reliability. Factor analyses confirmed that nCB-S and nCB-O fall on separate dimensions, and they provided preliminary evidence that nCB-S can be separated further into (a) helplessness/inferiority, (b) helplessness/vulnerability, (c) unlovability, and (d) worthlessness. Consistent with expectations, the scores on the nCB-S and nCB-O scales correlated positively with reports of negative experiences in childhood, attachment styles, anxiety, and depression. These preliminary results suggest that core beliefs can be measured in a reliable and valid manner and that the instrument proposed in this article can be used in studies designed to validate aspects of A. T. Beck's cognitive theory.