Table 2.
Examples of behavioral features with statistically significant differences between diagnosis categories of AD, MCI, and CN
| CN (N = 47) | MCI (N = 45) | AD (N = 26) | p | ||
| Gait | |||||
| Pace | Gait speed [m/s] | 1.33±0.16 A | 1.24±0.21 A | 1.07±0.18 C,M | < 0.0001 |
| Step length [m] | 0.68±0.07 M,A | 0.65±0.09 C,A | 0.58±0.07 C,M | < 0.0001 | |
| Rhythm | Stride time [s] | 1.04±0.07 A | 1.07±0.08 | 1.11±0.11 C | 0.0098 |
| Variability | Stride time variability (SD) [s] | 0.06±0.02 A | 0.07±0.03 | 0.08±0.03 C | 0.0292 |
| Left-right asymmetry | Step time left-right asymmetry [s] | 0.04±0.02 A | 0.05±0.03 | 0.07±0.05 C | 0.0182 |
| Postural control | Maximum toe clearance [m] | 0.13±0.02 M,A | 0.12±0.03 C | 0.11±0.02 C | 0.0009 |
| Speech | |||||
| Acoustic | MFCC1 (Picture description) | –496.2±31.9 A | –492.6±36.3 | –514.4±35.5 C | 0.0273 |
| Prosodic | Pitch variability (SD) [Hz] (Counting backwards) | 23.3±9.6 A | 19.6±9.4 | 16.8±5.4 C | 0.0148 |
| Proportion of pause duration (Semantic verbal fluency) | 0.75±0.07 A | 0.77±0.05 A | 0.84±0.07 C,M | < 0.0001 | |
| Linguistic | Proportion of mistakes (Subtraction) | 0.13±0.17 A | 0.20±0.23 | 0.36±0.28 C | 0.0005 |
| Honoré’s statistics [x10 3] (Picture description) | 1.93±0.96 A | 2.07±0.98 A | 1.34±0.65 C,M | 0.0061 | |
| Normalized total number of information units † [words/s] (Picture description) | 0.27±0.10 A | 0.26±0.12 A | 0.19±0.09 C,M | 0.0098 | |
| Drawing | |||||
| Kinematics | Drawing speed [mm/s] (TMT-B) | 102.0±18.5 A | 100.5±28.4 A | 79.0±20.8 C,M | 0.0006 |
| Pressure-related | Pressure variability (CV) (TMT-B) | 0.077±0.037 M,A | 0.124±0.068 C | 0.149±0.074 C | < 0.0001 |
| Time-related | Normalized pause duration between drawings ‡ [s/mm] (Sentence) | 0.016±0.009 A | 0.019±0.012 | 0.025±0.013 C | 0.0154 |
| Normalized pause duration between drawings ‡ [s/mm] (Pentagon) | 0.027±0.015 A | 0.032±0.021 | 0.043±0.029 C | 0.0328 | |
| Normalized pause duration between drawings ‡ [s/mm] (CDT) | 0.023±0.009 A | 0.031±0.030 | 0.045±0.039 C | 0.0121 | |
| TMT-specific | Time duration between nodes (TMT-A) | 1.10±0.22 A | 1.20±0.36 | 1.41±0.50 C | 0.0107 |
Data displayed as mean±standard deviations were assessed using one-way ANOVAs adjusted for age and sex. Bold values highlight statistically significant differences. Pairwise multiple comparisons (Bonferroni adjusted p values) were performed when comparing individual diagnostic groups. Significant differences between diagnosis categories are marked with C, M, or A (C: Different to CN, M: Different to MCI, A: Different to AD). †Data were normalized by the length of the speech ‡Data were normalized by total stroke length.