Silver Book Fact
Tandberg E, Larsen J, Aarsland D, Cummings J. The Occurrence of Depression in Parkinson’s Disease: A community-based study. Arch Neurol. 1996; 53: 175-9. https://www.ncbi.nlm.nih.gov/pubmed/8639068
Ravina B, Camicioli R, Como P. The Impact of Depressive Symptoms in Early Parkinson Disease. Neurology. 2007; 69(4): 342-7. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2031220/