Objective:Craft story recall test in the National Alzheimer’s Coordinating Center Uniformed Data Set 3 (NACC UDS3) neuropsychological battery has been employed to assess verbal memory and assist clinical diagnosis of mild cognitive impairment (MCI) and dementia. While a Chinese version of the test was adapted, no existing literature has examined the diagnostic validity of the test in Chinese Americans. This study aimed to evaluate the predictive validity of both immediate and delayed recall.Participants and Methods:The Chinese version of Craft Story was administered in to 78 Chinese participants per their language preference of Mandarin or Cantonese. Outcome measures were verbatim and paraphrase recall of the story immediately and after a 20-minute delay. A multiple linear regression was performed to investigate the association of each outcome measure with age, education, gender, age when moved to the U.S., years in the U.S., and testing language. To assess its diagnostic value, cutoff standard deviation scores of -1.5 and -2.0 from the mean of the clinically cognitive normal participants were generated for MCI and dementia diagnoses, respectively. Due to the small sample size, a normative group fitting the mean age (73 years), years of education (12 years), and the majority gender (female) of the current sample were used to identify standard cut points. A receiver-operating characteristic analysis was used to compare predicted diagnosis with actual clinical diagnosis obtained through patients’ overall performance and a consensus meeting by licensed clinicians.Results:Younger age (p < 0.05) and being tested in Mandarin (p < .01) were positively associated with immediate and delayed recall. Strong positive correlations between each measure were observed (all p < .001), indicating a significant relationship between information encoded and retained. Among all the participants, 15 (19.2%) were diagnosed with MCI and 22 (28.2%) with dementia. For MCI diagnosis, the standard cutoff scores demonstrated adequate sensitivity (verbatim=82%, paraphrase=91%) but low specificity (verbatim=44%, paraphrase=67%) in all outcome measures. For dementia diagnosis, delayed recall showed strong sensitivity (100%) and adequate specificity (75%) in both verbatim and paraphrasing scores. Immediate recall paraphrase (sensitivity = 95%, specificity = 50%) showed a better sensitivity but lower specificity than verbatim scoring (sensitivity = 86%, specificity = 58%). The accuracy was higher in delayed recall for both MCI and dementia diagnosis. A preliminary analysis on the optimal cut points indicated higher cutoff scores to distinguish MCI and dementia from clinically cognitive normal population, and from each other (e.g., the optimal cut point for delayed verbatim in distinguishing MCI from normal is 8.0 (sensitivity=89%, specificity=73%, AUC=84.3%)).Conclusions:Consistent with previous literature, Craft Story delayed recall served as a more accurate diagnostic tool for both MCI and dementia compared to immediate recall in older Chinese Americans. However, poor specificity might increase the chance of following false positive subjects in clinical trials. In addition, testing language appeared to impact performance on verbal memory recall of constructed information. Thus, future studies should focus on developing normative scores that address both the overall cultural differences of Chinese Americans and the heterogeneity within this population.
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