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The publication of a consensus definition of Parkinson disease (PD) psychosis in 2007 led to a rapid expansion of literature focusing on clinical aspects, mechanisms and treatment. The authors review this literature and discuss the evolving view of PD psychosis, from distinct classes of symptoms to a continuum progressing over the course of PD.
Real-world observational studies have the potential to answer questions about multiple sclerosis (MS) treatment that randomized controlled trials cannot. Trojano and colleagues discuss the pitfalls and necessary safeguards in observational studies, and the insights that such studies have provided into treatment decisions for patients with MS.
