Table 2.
Values for late-stage PD patients are presented as median [IQR, 25th–75th percentile].
| Parkinson’s disease patients (N = 24) | Normal value | |||
|---|---|---|---|---|
| Respiratory support for speech | ||||
| Vowel duration (s) | 5.8 [4.4–11.5.8] | 22.97 (1.1)b | ||
| Voice stability | ||||
| Pitch break time (s) | 1.24 [0.2–2.6.1] | NAa | ||
| Jitter (%) | 0.8 [0.5–1.1] | ≤0.5–1% | ||
| Voice variability | ||||
| Sentence F0SD (Hz) | 2.4 [1.6–4] | 2–4 Hz | ||
| Voice quality (Hz) | Male (N = 14) | Female (N = 10) | Male | Female |
| F0 | 125 [104–152] | 202 [160–226.8] | 128 (36)c | 198 (44)c |
Values for healthy subjects are presented as mean (SD), as reported in literature (25–28).
F0, fundamental frequency; Sentence F0SD, SD of speaking F0 during sentences.
aNot available (healthy voices should have no trouble in maintaining voicing during a sustained vowel. Thus is 0% of voice breaks. No standard values are available).
bNormal value for vowel duration is referred to a healthy population aged between 71 and 80 years old.
cNormal value for voice quality is referred to a healthy population aged between 55 and 80 years old.