title: Using computer-based video analysis in the study of fidgety movements.
abstract: OBJECTIVE
  Absence of fidgety movements (FM) in high-risk infants is a strong marker for later cerebral palsy (CP). FMs can be classified by the General Movement Assessment (GMA), based on Gestalt perception of the infant's movement pattern. More objective movement analysis may be provided by computer-based technology. The aim of this study was to explore the feasibility of a computer-based video analysis of infants' spontaneous movements in classifying non-fidgety versus fidgety movements.
  
  
  METHODS
  GMA was performed from video material of the fidgety period in 82 term and preterm infants at low and high risks of developing CP. The same videos were analysed using the developed software called General Movement Toolbox (GMT) with visualisation of the infant's movements for qualitative analyses. Variables derived from the calculation of displacement of pixels from one video frame to the next were used for quantitative analyses.
  
  
  RESULTS
  Visual representations from GMT showed easily recognisable patterns of FMs. Of the eight quantitative variables derived, the variability in displacement of a spatial centre of active pixels in the image had the highest sensitivity (81.5) and specificity (70.0) in classifying FMs. By setting triage thresholds at 90% sensitivity and specificity for FM, the need for further referral was reduced by 70%.
  
  
  CONCLUSIONS
  Video recordings can be used for qualitative and quantitative analyses of FMs provided by GMT. GMT is easy to implement in clinical practice, and may provide assistance in detecting infants without FMs.
authors.affiliation: Department of Clinical Services, Physiotherapy section, St. Olav University Hospital, Trondheim, Norway. lars.adde@ntnu.no
authors.forename: Lars
authors.initials: L
authors.lastname: Adde
authors.forename: Jorunn L
authors.initials: JL
authors.lastname: Helbostad
authors.forename: Alexander Refsum
authors.initials: AR
authors.lastname: Jensenius
authors.forename: Gunnar
authors.initials: G
authors.lastname: Taraldsen
authors.forename: Ragnhild
authors.initials: R
authors.lastname: Støen
mesh_terms: D002547:Cerebral Palsy / Q000175:diagnosis; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D007223:Infant; D018730:Infant Behavior / Q000502:physiology*; D008297:Male; D009043:Motor Activity / Q000502:physiology*; D012680:Sensitivity and Specificity; D014741:Video Recording