Adaptation and validation of the “cognitive complaints in bipolar disorder rating assessment” (COBRA) in Chinese bipolar patients

Abstract

There is no specific instrument available to measure cognitive deficits as reported by bipolar patients in China. Therefore, if discrepancies between bipolar patients' reports and the results of neuropsychological tests which have been described in other countries existing or not in Chinese bipolar disorder patients have not been known yet. And it is completely blank about the subjective cognition of these Chinese bipolar patients. The aim of the study is to revise and validate a specific, user-friendly, brief instrument named the "cognitive complaints in bipolar disorder rating assessment" (COBRA) into Chinese version. The total sample (N=255) included 125 bipolar disorder patients and 130 healthy controls. The psychometric properties of the COBRA (e.g. internal consistency, retest reliability, discriminative validity, concurrent validity, content validity, item analysis, confirmatory factor analysis, ROC curve and feasibility) were analyzed. The Chinese version of the COBRA had very high internal consistency (Cronbach's alpha=0.905) and retest reliability (ICC=0.902). Confirmatory factor analysis validated the one-factor model and the cut-off value to discriminate the patients and controls was 11.Bipolar patients experienced greater cognitive complaints compared to control group suggesting a discriminative validity of the instrument. No significant correlation was found between the COBRA and the total Montreal Cognitive Assessment Scale (MoCA), except for single measures related to executive function (phonemic fluency, p=0.045), verbal memory (delayed recall, p=0.004). Cross-sectional design, no specific or unspecific but reliable instrument in Chinese to assess subjective cognitive difficulties in mental disorders for criterion validity or convergent validity analysis. The Chinese version of the COBRA showed to be a simple and reliable instrument to assess subjective cognitive complaints in Chinese bipolar patients.