Protocol: Using N-of-1 tests to identify responders to melatonin for sleep disturbance in Parkinson's disease.

Background: 40% of Parkinson's Disease (PD) sufferers experience insomnia, impacting health and quality of life for patients and family members, especially carers. There is little evidence that current treatments are effective.

Objectives: To determine the effectiveness of melatonin in reducing insomnia in 44 individuals with PD using N-of-1 trials.