Fact · Accessibility and health
89percent
As many as 89 percent of people with Parkinson's disease develop speech disorders.
Checked against its source on October 16, 2026
In the source's own words
“As many as 89% of people with Parkinson's disease (PD) develop speech disorders.”
Speech treatment in Parkinson's disease: Randomized controlled trial (RCT), Lorraine Ramig et al., Movement Disorders, 2018, Abstract, Background.
Open the original (DOI 10.1002/mds.27460)- What it measures
- The speech changes in Parkinson's disease are called hypokinetic dysarthria: reduced loudness, monotone, hoarse or breathy voice and imprecise articulation. These are exactly the features that raise word error rates in standard speech recognition.
- What it does not show
- An upper estimate ('as many as') cited from earlier studies in the background of a treatment trial, not a new prevalence measurement.