title: An Ambulatory Tremor Score for Parkinson's Disease.
abstract: While tremor in Parkinson's Disease (PD) can be characterised in the consulting room, its relationship to treatment and fluctuations can be clinically helpful.
  
  
  
  To develop an ambulatory assessment of tremor of PD.
  
  
  
  Accelerometry data was collected using the Parkinson's KinetiGraph System (PKG, Global Kinetics). An algorithm was developed, which could successfully distinguish been subjects with a resting or postural tremor that involved the wrist whose frequency was greater than 3 Hz. Percent of time that tremor was present (PTT) between 09 : 00 and 18 : 00 was calculated.
  
  
  
  This algorithm was applied to 85 people with PD who had been assessed clinically for the presence and nature of tremor. The Sensitivity and Selectivity of a PTT ≥0.8% was 92.5% and 92.9% in identifying tremor, providing that the tremor was not a fine kinetic and postural tremor or was not in the upper limb. A PTT >1% provide high likely hood of the presence of clinical meaningful tremor. These cut-offs were retested on a second cohort (n = 87) with a similar outcome. The Sensitivity and Selectivity of the combined group was 88.7% and 89.5% respectively. Using the PTT, 50% of 22 newly diagnosed patients had a PTT >1.0%.The PKG's simultaneous bradykinesia scores was used to find a threshold for the emergence of tremor. Tremor produced artefactual increase in the PKG's dyskinesia score in 1% of this sample.
  
  
  
  We propose this as a means of assessing the presence of tremor and its relationship to bradykinesia.
authors: Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia.|Centre for Clinical Neurosciences and Neurological Research, St Vincent's Hospital Melbourne, Fitzroy, VIC, Australia.
authors: Michelle
authors: M
authors: Braybrook
authors: Global Kinetics Corporation, Melbourne, VIC, Australia.
authors: Sam
authors: S
authors: O'Connor
authors: Global Kinetics Corporation, Melbourne, VIC, Australia.
authors: Philip
authors: P
authors: Churchward
authors: Bionics Institute, East Melbourne, VIC, Australia.|Medical Bionics Department, The University of Melbourne, Parkville, VIC, Australia.
authors: Thushara
authors: T
authors: Perera
authors: Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia.|Centre for Clinical Neurosciences and Neurological Research, St Vincent's Hospital Melbourne, Fitzroy, VIC, Australia.
authors: Parisa
authors: P
authors: Farzanehfar
authors: Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia.|Centre for Clinical Neurosciences and Neurological Research, St Vincent's Hospital Melbourne, Fitzroy, VIC, Australia.|Department of Medicine, University of Melbourne, Parkville, VIC, Australia.
authors: Malcolm
authors: M
authors: Horne
mesh_terms: D061725:Accelerometry / Q000592:standards*; D000368:Aged; D000465:Algorithms; D005260:Female; D006801:Humans; D018476:Hypokinesia / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000150:complications*; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D014202:Tremor / Q000175:diagnosis* / Q000209:etiology
keywords: Parkinson disease; Tremor; ambulatory monitoring; tremor dominant 
  Parkinsons