Aims To determine if perceptual speech measures distinguish people with Parkinson's (PD), multiple system atrophy with predominant parkinsonism (MSA-P) and progressive supranuclear palsy (PSP). Methods Speech-language therapists blind to patient characteristics employed clinical rating scales to evaluate speech/voice in 24 people with clinically diagnosed PD, 17 with PSP, 9 with MSA-P, matched for disease duration (mean 4.9 years, SD 2.2). Results No consistent intergroup differences appeared

more »

... specific speech/voice variables. People with PD were significantly less impaired on overall speech/voice severity. Analyses by severity suggested further investigation around laryngeal, resonance and fluency changes may characterise individual groups Conclusion MSA-P and PSP compared to PD were distinguished by severity of speech/voice deterioration, but individual speech/voice parameters failed to consistently differentiate groups.