Abstract:

Objective To explore the feasibility of complex Chinese Character (CCC) “biang” as a simple cognitive assessment tool. Methods According to the Rey-Osterrieth complex figure test (ROCF) scoring system, CCC scoring system with a total score of 28 points was developed. Randomized outpatients (≥50 years old) were enrolled. The correlation between CCC and other neuropsychological test, namely ROCF, clock drawing test (CDT), bells test, auditory verbal learning test (AVLT), free and cued selective reminding test (FCSRT), digital span test (forward and backward), was preliminarily assessed by small sample study. Intra-class correlation coefficients(ICC) method was applied to assess retest reliability of CCC. The elderly(≥50 years old) patients were randomly enrolled in the community epidemiological investigation cohort, and CCC and other cognitive scales (trail making test A&B, word list, semantic verbal fluency) were evaluated. The exploratory factor analysis(EFA) and multiple regression analysis were used to evaluate the construct validity of CCC. Results In a small sample of 22 outpatients, CCC score was more correlated with verbal memory, CCC delay 20 min score had the highest correlation with index of sensitivity of cueing, and Spearman correlation coefficient was 0.634(P=0.002). By ICC method(n=12), the correlation coefficient of copying score of 6 months in ICC group was 0.657, and the correlation coefficient of delayed recall score in ICC group was 0.502, showing good consistency. In the large sample cohort population study (n=583), exploratory factor analysis showed that among five indicators of CCC scoring system (copy score, delay 5 min score, delay 20 min score, delay 5 min retention score, delay 20 min retention score), delay 20 min score was the most loaded in verbal memory factor. After adjusting for gender, age and education, the variance of 20.6% delayed 20 min score could be explained by 13.3% verbal memory storage (word list delayed recall score) and 7.3% verbal memory retrieval (word list recognition score). A total of 42 mild cognitive impairment (MCI) patients and 40 controls were recruited for the CCC scale test, and it showed that the sensitivity of the CCC scale to diagnose MCI was 67% and the specificity was 53%. Conclusions CCC scale has good reliability and validity. CCC test is mainly related to verbal memory, and the delay 20 min score consists of verbal memory.

Key words: Complex Chinese character test, Verbal memory, Cognitive screening tool