JMIR Publications

ABSTRACT

Background:

The emergence of disease-modifying treatment options for Alzheimer's disease is creating a paradigm shift in strategies to identify patients with mild symptoms in primary care settings. Systematic reviews on digital cognitive tests reported that most showed diagnostic performance comparable to that of paper-and-pencil tests for mild cognitive impairment and dementia. However, most studies have small sample sizes, less than 100 individuals, and are based on case-control or cross-sectional designs.

Objective:

To examine the predictive validity of Japanese Cognitive Function Test (J-Cog), a new computerized cognitive battery test, for dementia development.

Methods:

We randomly assigned 2,520 older adults (average age: 72.7 ± 6.7 years) to derivation and validation groups to determine and validate cutoff points for the onset of dementia. Mini-Mental State Examination (MMSE) was used for comparison purposes. J-Cog consists of 12 tasks that assess orientation, designation, attention and calculation, mental rotation, verbal fluency, sentence completion, working memory, logical reasoning, attention, common knowledge, word memory recall, and episodic memory recall. Onset of dementia was monitored for 60 months.

Results:

Significant hazard ratios (HRs) for dementia incidence were found using MMSE cut point 23/24 and J-Cog (MMSE 23/24: HR 1.93, 95% confidence interval 1.13–3.27, J-Cog: HR 2.42, 95% confidence interval 1.50–3.93). The C-statistic was above 0.8 for all cutoff points. Akaike information criterion with MMSE cutoff point 23/24 as a reference showed a poor fit at MMSE cutoff point 28/29 and a good fit at J-Cog.

Conclusions:

The J-Cog has higher accuracy in predicting the development of dementia than the MMSE and has advantages for use in the community as a test of cognitive function which can be administered by non-professionals.