Application of a multidimensional computerized adaptive test for a Clinical Dementia Rating Scale through computer-aided techniques

BACKGROUND: With the increasingly rapid growth of the elderly population, individuals aged 65 years and above now compose 14% of Taiwanese citizens, thereby making Taiwanese society an aged society. A leading factor that affects the elderly population is dementia. A method of precisely and efficiently examining patients with dementia through multidimensional computer adaptive testing (MCAT) to accurately determine the patients’ stage of dementia needs to be developed. This study aimed to develop online MCAT that family members can use on their own computers, tablets, or smartphones to predict the extent of dementia for patients responding to the Clinical Dementia Rating (CDR) instrument. METHODS: The CDR was applied to 366 outpatients in a hospital in Taiwan. MCAT was employed with parameters for items across eight dimensions, and responses were simulated to compare the efficiency and precision between MCAT and non-adaptive testing (NAT). The number of items saved and the estimated person measures was compared between the results of MCAT and NAT, respectively. RESULTS: MCAT yielded substantially more precise measurements and was considerably more efficient than NAT. MCAT achieved 20.19% (= [53 − 42.3]/53) saving in item length when the measurement differences were less than 5%. Pearson correlation coefficients were highly consistent among the eight domains. The cut-off points for the overall measures were − 1.4, − 0.4, 0.4, and 1.4 logits, which was equivalent to 20% for each portion in percentile scores. Substantially fewer items were answered through MCAT than through NAT without compromising the precision of MCAT. CONCLUSIONS: Developing a website that family members can use on their own computers, tablets, and smartphones to help them perform online screening and prediction of dementia in older adults is useful and manageable. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s12991-019-0228-4) contains supplementary material, which is available to authorized users.