The THINC-it tool: temporal sensitivity to change over time

Introduction: Cognitive dysfunction is believed to be among the core features of Bipolar Depression(BD-D). However, its evaluation and available treatments are limited. Here, we conducted a longitudinal follow-up clinical trial using the THINC-it tool to evaluate temporal sensitivity to change over time in cognitive function among patients with bipolar depression from a Chinese cohort. It is helpful to verify whether the scale can continuously and reliably measure cognitive function in different time points and reduce the measurement error caused by time factors. Hope our findings could provide insights into the significance of the THINC-it tool as an iterative clinical cognitive evaluation tool.

Methods: A total of 120 patients with bipolar depression(40 males and 80 females, respectively) alongside 100 healthy controls(23 males and 77 females, respectively) were recruited in the study. All participants were interviewed for 8 weeks, using the 17-item Hamilton Depression Rating Scale (HAMD-17) and the Young Mania Rating Scale(YMRS). The primary dependent measure was the previously validated THINC-it tool, followed by psychometric analysis.

Results: Repeated measures of the THINC-it tool at baseline, one-week, and eight-week periods were conducted after controlling for age, gender, and education effects. Results from the general linear model revealed no significant time differences in variances(P > 0.05). Similarly, adjusting for confounding factors (age, gender, education, and HAMD-17 scores), results from the longitudinal analysis showed that there were no significant differences in cognitive impairment over time(P > 0.05). However, we found significant differences between BD-D and Healthy Control(HC) groups with regards to Spotter, Codebreaker, Trails, Perceived Deficits Questionnaire for Depression-5-items(PDQ-5-D), and THINC-it Total composite(P < 0.05), but not in Symbol Check (p = 0.191).

Conclusion: These findings indicate that the THINC-it tool effectively detects sensitivity to change in groups and maintains stability at times, indicating that it is a feasible and reliable instrument for evaluating cognitive dysfunction in Chinese patients with bipolar depression.