Background: Cognitive impairment is one of the core features of bipolar depression. A unified, reliable, and valid assessment tool is key to screening and assessing cognitive impairment. The THINC-Integrated Tool (THINC-it) is a simple and quick battery for screening cognitive impairment in patients with major depressive disorder. However, the use of the tool has not been validated in patients with bipolar depression.
Methods: The cognitive functions of 120 patients with bipolar depression and 100 healthy controls were evaluated using the THINC-it tool including Spotter, Symbol Check, Codebreaker, Trials, and the only one subjective test (PDQ-5-D) and five corresponding standard tests. A psychometric analysis of the THINC-it tool was performed.
Results: The overall Cronbach's alpha coefficient of the THINC-it tool was 0.815. The intra-group correlation coefficient (ICC) of retest reliability ranged from 0.571 to 0.854 (P<0.001), while the correlation r of parallel validity ranged from 0.291 to 0.921 (P<0.001). There were significant differences in the two groups Z-scores of THINC-it total score, Spotter, Codebreaker, Trails, and PDQ-5-D (P<0.05). Construct validity was analyzed using exploratory factor analysis (EFA). The Kaiser-Meyer-Olkin (KMO) value was 0.749. Using Bartlett's Sphericity test, the χ 2 (10) value was 198.257 (P<0.001). The factor loading coefficients of Spotter, Symbol Check, Codebreaker, and Trails on the common factor 1 were -0.724, 0.748, 0.824, and -0.717, respectively, and the factor loading coefficient of PDQ-5-D on the common factor 2 was 0.957. Results revealed that the correlation coefficient of the two common factors was 0.125.
Conclusion: The THINC-it tool has good reliability and validity in assessing patients with bipolar depression.
Keywords: THINC-it tool; bipolar disorder; cognitive impairment; reliability; validity.
© 2023 Zhu et al.