Reliability and validity of Chinese version of perceived deficits questionnaire for depression in patients with MDD

Although cognitive symptoms are prevalent and negatively affect psychosocial functioning, they are not commonly assessed in clinical practice, particularly in China. Perceived Deficits Questionnaire for Depression (PDQ-D) provides a subjective measure of cognitive dysfunction. This study aimed to examine the psychometric properties of Chinese version of PDQ-D in patients with MDD. The study sample comprised of 129 patients with MDD and 128 community volunteers. All patients with MDD were assessed with PDQ-D, Sheehan Disability Scale (SDS), Work Productivity and Activity Impairment: Specific Health Problem (WPAI-SPH), Patient Health Questionnaire-9 item (PHQ-9), and Digit Symbol Substitution Test (DSST). Community volunteers were assessed with PDQ-D, PHQ-9 and DSST. The Chinese version of PDQ-D showed excellent internal consistency and test-retest reliability. Three factors were identified and together explained 62.48% of the total variance. Validity of the PDQ-D was supported by its significant correlations with self-reported impaired work productivity, disability in all sub-domains of SDS, along with significant difference between community volunteers and MDD patients in PDQ-D. The questionnaire also significantly correlated with PHQ-9, but no correlation between PDQ-D and DSST was found. The Chinese version of the PDQ-D was found to be psychometrically valid to evaluate subjective cognitive dysfunction in patients with MDD.