Table 5.

Failure and difficulty evaluation of the current cognitive training games.

Task	Cognitive training domain	Failure evaluation	Difficulty evaluation
Cube counting	Attention executive function memory visuospatial function	•The hidden cubes were difficult to discriminate •The icons were too small to read and tap	Difficult
Time discrimination	Attention executive function memory Visuospatial function	•Input the answer by tapping the clock	Easy
Amount comparison	Attention executive function memory visuospatial function	•Incorrect counting •The coin icons were too small to discriminate	Difficult
Drawing	Attention executive function memory visuospatial function	•No failure	Easy
Reading cards	Attention executive function memory language visuospatial function	•No failure	Easy