Measuring Cognition in a Geriatric Outpatient Clinic: Rasch Analysis of the Montreal Cognitive Assessment

作者：Koski Lisa^*; Xie Haiqun; Finch Lois

来源：Journal of Geriatric Psychiatry and Neurology, 2009, 22(3): 151-160.

DOI：10.1177/0891988709332944

• MoCA
• Rasch analysis
• cognition
• aging
• geriatric
• assessment

Objective: To evaluate the psychometric properties of the Montreal Cognitive Assessment as a quantitative measure of cognitive ability. Data analyzed: A total of 222 cases extracted from a clinical database (57-91 years) of patients screened for cognitive impairment in outpatient geriatric assessment clinics. Data collected: Demographic information and individual item responses to Montreal Cognitive Assessment. Results: Comparison of the data with a unidimensional Rasch model indicated that the total score obtained by summing across all items yields a reliable (0.75) quantitative estimate of global cognitive ability. All items fit the model and together spanned a range of difficulty from - 3.75 to 2.88 logits. Items were assessed for differential item functioning across such patient characteristics as age, education, and language spoken. We provide a table for converting Montreal Cognitive Assessment total scores onto a linearly scaled score, with guidelines for interpreting changes in Montreal Cognitive Assessment score in terms of their statistical significance. Conclusions: The Montreal Cognitive Assessment can provide a reliable and valid quantitative estimate of cognitive ability in a geriatric cognitive disorders clinic setting.

• 出版日期2009-9