The purpose of the study is to investigate the feasibility of using the commercially available Parkinson's KinetiGraph Data Logger (PKG) to quantitatively assess motor fluctuations in Parkinson's Disease (PD) patients. A reliable and objective assessment of motor fluctuations would support the general neurologists in the referral of PD patients to the Deep Brain Stimulation (DBS) surgical centers and facilitate the DBS eligibility evaluation of PD patients usually done by the DBS specialists at the DBS surgical centers.