title: Electromagnetic motion analysis in the assessment of surgical skill: Relationship between time and movement.
abstract: BACKGROUND
  Electromagnetic motion analysis is a promising method of assessing surgical skill in a skills-laboratory setting. There is a very strong correlation between movement and time data, and this study was conducted to determine whether this relationship is fixed, or whether it can vary.
  
  
  METHODS
  : After a pilot study, four subjects were recruited. Each performed 30 trials of a simple standardized suturing task, alternating between 'normal', 'precise', and 'fast' strategies. The number of movements, and time to complete each task were recorded.
  
  
  RESULTS
  Comparing the 'fast' to 'normal' strategies, there was a significant decrease in total number of movements per trial (P < 0.001), and time taken (P < 0.001). Regression analysis was performed to examine the relationship between the time taken and the number of movements, and revealed significant differences between both the fast (P = 0.006), and precise (P = 0.002) strategies, when compared to the normal strategy.
  
  
  CONCLUSIONS
  This study confirms that the relationship between time and movements is not fixed, but varies with the operative strategy adopted for this simple suturing task.
authors.affiliation: Imperial College of Science, Technology, and Medicine Academic Surgical Unit, St Mary's Hospital, London, United Kingdom. s.mackay@ic.ac.uk
authors.forename: Sean
authors.initials: S
authors.lastname: Mackay
authors.forename: Vivek
authors.initials: V
authors.lastname: Datta
authors.forename: Mirren
authors.initials: M
authors.lastname: Mandalia
authors.forename: Paul
authors.initials: P
authors.lastname: Bassett
authors.forename: Ara
authors.initials: A
authors.lastname: Darzi
mesh_terms: D002983:Clinical Competence; D055590:Electromagnetic Phenomena; D013502:General Surgery; D006801:Humans; D009038:Motion; D013536:Suture Techniques; D013996:Time and Motion Studies