Validation and Functional Relevance of the Short Form of the Perceived Deficits Questionnaire for Depression for Japanese Patients with Major Depressive Disorder

Neuropsychiatr Dis Treat. 2022 Nov 2:18:2507-2517. doi: 10.2147/NDT.S381647. eCollection 2022.

Abstract

Purpose: To validate the five-item version of the Perceived Deficits Questionnaire for Depression (PDQ-D-5) for assessing subjective cognitive function in Japanese patients with major depressive disorder (MDD) using data from the PERFORM-J study.

Patients and methods: A total of 518 Japanese outpatients diagnosed with MDD were assessed on severity of depressive symptoms, cognitive function, social and work function, and quality of life (QoL) over 6 months following initiation of antidepressant therapy. This post hoc analysis evaluated the internal consistency and convergent validity of the PDQ-D-5 in relation to the original PDQ-D-20. Correlations of scores on these measures were examined at each time point and over time. The same set of analyses was explored between PDQ-D-5 and the Patient Health Questionnaire-nine-item (PHQ-9), Montgomery-Asberg Depression Rating Scale (MADRS), Digit Symbol Substitution Test (DSST), five-level version of EQ-5D (EQ-5D-5L), Sheehan Disability Scale (SDS), and Work Productivity and Activity Impairment (WPAI) questionnaire.

Results: PDQ-D-5 scores showed good internal consistency. Strong positive correlations were observed between PDQ-D-5 and PDQ-D-20 at each time point (correlation coefficient: baseline, 0.94; month 1, 0.94; month 2, 0.96; month 6, 0.96) and over time (0.92) (all p < 0.0001). Longitudinally, there were positive correlations between PDQ-D-5 scores versus those on the PHQ-9, MADRS, and SDS. Similarly, negative correlations were noted between PDQ-D-5 scores and EQ-5D-5L and DSST scores to a variable degree. There were moderate positive correlations over time between PDQ-D-5 and all WPAI subscale scores except those on absenteeism.

Conclusion: PDQ-D-5 scores rated in Japanese patients with MDD were found to adequately represent scores on the PDQ-D-20. The short version also showed associations with several measures of functional outcome, depression severity and QoL. This validates the PDQ-D-5 as a feasible and clinically reliable tool to assess subjective experience on cognition, which is applicable to time-limited consultations.

Umin clinical trials registry for primary study: UMIN000024320.

Keywords: PDQ-D-20; PDQ-D-5; cognition; functional impairment; major depressive disorder.

Grants and funding

This study was funded by Takeda Pharmaceutical Company Limited, Japan. Medical writing support was provided by Emily Manktelow, PhD, of Oxford PharmaGenesis, Melbourne, Australia and funded by Takeda Pharmaceutical Company Limited and Lundbeck Japan KK.