Disclaimer: For research use in patients diagnosed with Parkinson's disease. Do not use for patient care. If you are a patient, ask your physician about Parkinson's disease and memory. Probability estimates, even if high, do not indicate predictive certainty. There is currently no treatment available for preventing cognitive decline or dementia in Parkinson's disease. Patients with abnormal scores may experience unwanted side effects such as anxiety or depression. This risk assessment tool uses information from nine longitudinal cohorts (academic cohorts, population-based cohorts, and clinical trials) to estimate the chance of a person with Parkinson's disease of developing global cognitive impairment within 10 years from disease onset. The risk prediction tool may not apply to patients with Parkinson's disease in the general population.