Neuropsychiatric Burden Is a Predictor of Early Freezing and Motor Progression in Drug-Naïve Parkinson's Disease. - Jeong, Seong Ho; Yoo, Han Soo; Chung, Seok Jong; Jung, Jin Ho; Lee, Yang Hyun; Baik, Kyoungwon; Sohn, Young H.; Lee, Phil Hyu (Journal of Parkinson's Disease, 2021)