Table 2.
Comparison of the voice parameters used between older people with nondegenerative MCI and those expected to develop AD. Mann-Whitney U test of independent samples and means of the two groups.
| Parameters | nodMCI mean (SD) | preAD mean (SD) | Mann-Whitney U (standardised test) |
|---|---|---|---|
| Duration parameters | |||
| Duration (reading time) | 47.48 (22.20) | 61.74 (20.95) | 243 (-2.791)∗∗ |
| Phonation time (sec) | 32.35 (10.39) | 39.44 (8.75) | 213 (-3.153)∗∗ |
| Speech rate | 3.35 (0.80) | 3.07 (0.92) | 583 (1.308) |
| Pauses number | 25.79 (16.34) | 34.23 (14.64) | 283 (-2.310)∗ |
| Speech fluency and rhythm parameters | |||
| Normalized_PVI | 54.27 (5.42) | 59.97 (5.76) | 215 (-3.128)∗∗ |
| Syll_Interv_DAverage | 0.19 (0.03) | 0.20 (0.02) | 416 (-0.705) |
| Syll_Interv_ΔStandar | 0.10 (0.02) | 0.11 (0.02) | 246 (-2.755)∗∗ |
| VARCO of syllabic interval duration | 0.51 (0.07) | 0.55 (0.09) | 349 (-1.513) |
| Syllabus interval number | 154.01 (51.88) | 178.08 (33.94) | 223 (-3.033)∗∗ |
| Articulation rate | 4.63 (0.59) | 4.54 (0.60) | 519 (0.537) |
| Fundamental frequency and spectral analysis | |||
| F0 mean (Hz) | 168.61 (28.90) | 164.82 (20.21) | 514 (0.476) |
| F0 mean (Hz_men) | 138.86 (25.17) | 138.84 (16.31) | 41 (0.077) |
| F0 mean (Hz_women) | 172.12 (16.34) | 170.09 (13.73) | 250 (0.230) |
| Asymmetry (skewness, Hz) | 11.33 (4.14) | 8.62 (4.38) | 645 (2.056)∗ |
| Center of gravity (CoG_Hz) | 446 (98) | 568 (227) | 321 (-1.851) |
| Center of gravity SD (CoG_sd) | 547 (191) | 753 (318) | 276 (-2.393)∗ |
| LTAS mean (dB) | 32.46 (2.31) | 30.20 (2.00) | 763 (3.478)∗∗ |
| LTAS mean (dB_men) | 32.41 (2.64) | 30.47 (2.33) | 30 (-0.878) |
| LTAS mean (dB_women) | 32.48 (2.20) | 30.07 (1.97) | 401 (3.247)∗∗ |
| LTAS SD (dB) | 40.32 (2.10) | 38.16 (2.82) | 738 (3,177)∗∗ |
| LTAS SD (dB_men) | 40.21 (2.31) | 38.46 (3.08) | 57 (1.317) |
| LTAS SD (dB_women) | 40.37 (2.03) | 38.03 (2.88) | 388 (2.987)∗∗ |
| LTAS range 50-1000 Hz | 44.87 (2.03) | 43.26 (2.37) | 694 (2.646)∗∗ |
| LTAS range 50-1000 Hz_men | 46.24 (2.12) | 44.76 (3.27) | 51 (0.852) |
| LTAS range 50-1000 Hz_women | 46.40 (2.06) | 43.98 (4.12) | 369 (2.608)∗∗ |
| LTAS 1 kHz-2 kHz | 27.13 (3.29) | 26.21 (4.98) | 513 (0.464) |
| LTAS 2 kHz-4 kHz | 17.87 (4.59) | 17.94 (2.98) | 480 (0.066) |
| Intensity parameters | |||
| Intensity mean (dB) | 75.36 (1.77) | 73.63 (2.00) | 735 (3.141)∗∗ |
| Intensity mean (dB_men) | 74.94 (0.41) | 73.94 (0.91) | 55 (1.162) |
| Intensity mean (dB_women) | 75.98 (0.41) | 73.51 (0.60) | 390 (3.027)∗∗ |
| Intensity mean_SD (dB) | 17.28 (10.54) | 14.77 (2.94) | 551 (0.922) |
| Intensity SD (dB_men) | 19.24 (14.31) | 12.76 (4.26) | 51 (0.852) |
| Intensity SD (dB_women) | 16.55 (8.78) | 15.66 (1.79) | 198 (-0.809) |
| Amplitude minimum | -9.08 (13.53) | 25.01 (12.44) | 551 (0.922) |
| Intensity Minim (dB_men) | -23.19 (129.34) | 27.59 (14.61) | 46 (0.465) |
| Intensity Minim (dB_women) | -3.76 (107.83) | 23.85 (12.14) | 285 (0.929) |
| Intens Diferenc Max-Min Mean (dB) | 95.55 (13.40) | 61.76 (12.26) | 377 (-1.175) |
| Intens Dif Max-Min (dB_men) | 109.22 (129.34) | 58.79 (14.07) | 34 (-0.465) |
| Intens Dif Max-Min (dB_women) | 90.37 (107.68) | 63.07 (12.03) | 181 (-1.149) |
| Acoustic Voice Quality parameters | |||
| Jitter (local) | 2.42 (1.07) | 2.35 (0.66) | 427 (-0.567) |
| Shimmer Loc (dB) | 1.12 (0.27) | 1.19 (0.22) | 394 (-0.965) |
| Voice breaks (%) | 38.93 (11.01) | 43.93 (13.24) | 333 (-1.706) |
| Acoustic Voice Quality Index (AVQI) | 6.00 (1.18) | 6.17 (0.95) | 425 (-0.597) |
| HNR (dB) | 12.96 (3.50) | 11.91 (3.18) | 570 (1.151) |
∗ P < 0.05; ∗∗P < 0.01; ∗∗∗P < 0.001.