Background: Subjectively experienced cognitive impairment is common in patients with mood disorders. The British Columbia Cognitive Complaints Inventory (BC-CCI) is a 6-item scale that measures perceived cognitive problems. The purpose of this study is to examine the reliability of the scale in healthy volunteers and depressed patients and to evaluate the sensitivity of the measure to perceived cognitive problems in depression.
Methods: Participants were 62 physician-diagnosed inpatients or outpatients with depression, who had independently confirmed diagnoses on the Structured Clinical Interview for DSM-IV, and a large sample of healthy community volunteers (n=112).
Results: The internal consistency reliability of the BC-CCI was α=.86 for patients with depression and α=.82 for healthy controls. Principal components analyses revealed a one-factor solution accounting for 54% of the total variability in the control sample and a 2-factor solution (cognitive impairment and difficulty with expressive language) accounting for 76% of the variance in the depression sample. The total score difference between the groups was very large (Cohen's d=2.2).
Conclusions: The BC-CCI has high internal consistency in both depressed patients and community controls, despite its small number of items. The test is sensitive to cognitive complaints in patients with depression.