The Michael J. Fox Foundation & the University of Colorado Denver conducted this survey of 1,900 patients over 4 months. Most of the patients reported mild benefits to their sleep, mood, & pain.
Additionally, some were able to reduce their use of prescription medications prescribed to treat those symptoms. The study results were presented at the 2021 American Academy of Neurology Annual Meeting. Most of the patients administered cannabis extracts once daily through an oral (swallowed) dose.
The article about their study is on the Michael J. Fox foundation website here.