title: Quantified measurement of activity provides insight into motor function and recovery in neurological disease.
abstract: BACKGROUND
  A direct quantitative measurement of locomotor activity in an individual's own environment over an extended period may help in evaluating the impact of impairments in neurological disorders.
  
  
  OBJECTIVE
  To investigate the reliability and validity of activity monitoring in neurological patients and healthy subjects.
  
  
  METHODS
  Initial reliability studies were completed on 10 healthy subjects and 10 mobility restricted neurological patients. Validity was investigated using 7 days of ambulatory monitoring with the Step Watch( step activity monitor, laboratory based measures of gait and the Rivermead Mobility Index (RMI) in 10 patients with multiple sclerosis, 10 with Parkinson's disease, and 10 with a primary muscle disorder. Additionally, 30 healthy subjects participated in the study. Two clinical illustrations of ambulatory monitoring are provided.
  
  
  RESULTS
  The mean (range) right step count of 7 days of monitoring in both healthy and neurological patients proved a reliable measure of activity (intra-class correlations 0.89 and 0.86 respectively). The 7 day mean (range) right step count was 5951 (2886-9955) in healthy subjects, 3818 (1611-5391) in patients with Parkinson's disease, 3003 (716-5302) in those with muscular disorders, and 2985 (689-5340) in those with multiple sclerosis. A moderate correlation was noted between 7 day mean step count and gait speed (r = 0.45, p = 0.01) in the grouped neurological patients but not the RMI (r(s) = 0.3, p = 0.11).
  
  
  CONCLUSIONS
  Ambulatory monitoring provides a reliable and valid measure of activity levels. Neurological patients, living independently, demonstrate lower activity levels than healthy matched controls. Ambulatory monitoring as an outcome measure has potential for improving the evaluation of ambulation and providing insight into participation.
authors.affiliation: Department of Physiotherapy Education, University of Wales College of Medicine, Cardiff, UK.
authors.forename: M E
authors.initials: ME
authors.lastname: Busse
authors.forename: O R
authors.initials: OR
authors.lastname: Pearson
authors.forename: R
authors.initials: R
authors.lastname: Van Deursen
authors.forename: C M
authors.initials: CM
authors.lastname: Wiles
mesh_terms: D000328:Adult; D000368:Aged; D001696:Biomechanical Phenomena / Q000379:methods; D004185:Disability Evaluation; D005684:Gait / Q000502:physiology; D006801:Humans; D008124:Locomotion / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D018670:Monitoring, Ambulatory / Q000295:instrumentation / Q000379:methods* / Q000706:statistics & numerical data; D009043:Motor Activity / Q000502:physiology*; D009103:Multiple Sclerosis / Q000175:diagnosis / Q000503:physiopathology; D009422:Nervous System Diseases / Q000175:diagnosis* / Q000503:physiopathology; D010300:Parkinson Disease / Q000175:diagnosis / Q000503:physiopathology; D020127:Recovery of Function / Q000502:physiology; D015203:Reproducibility of Results; D016138:Walking / Q000502:physiology