FIGURE 1.

The neuropsychological tests grouped by disease stages. (a) The test of total verbal fluency test (VFT) score, mini–mental state examination (MMSE), symbol digit modalities test (SDMT) were getting worse among patients in different disease stages after age and education attainment adjusted (p < .001), whereas total recall in Hopkins verbal learning test–revised (HVLT‐R) did not have statistical significance. (b) Three parts in Stroop test, including word reading, color naming, and interference task became worse with the disease progression (p < .001); (c) TMT‐A showed the statistically significant decline among different disease stages. *p < .05; **p < .01; ***p < .001; ns: p > .05.