title: Relevance of motion-related assessment metrics in laparoscopic surgery.
abstract: BACKGROUND
  Motion metrics have become an important source of information when addressing the assessment of surgical expertise. However, their direct relationship with the different surgical skills has not been fully explored. The purpose of this study is to investigate the relevance of motion-related metrics in the evaluation processes of basic psychomotor laparoscopic skills and their correlation with the different abilities sought to measure.
  
  
  METHODS
  A framework for task definition and metric analysis is proposed. An explorative survey was first conducted with a board of experts to identify metrics to assess basic psychomotor skills. Based on the output of that survey, 3 novel tasks for surgical assessment were designed. Face and construct validation was performed, with focus on motion-related metrics. Tasks were performed by 42 participants (16 novices, 22 residents, and 4 experts). Movements of the laparoscopic instruments were registered with the TrEndo tracking system and analyzed.
  
  
  RESULTS
  Time, path length, and depth showed construct validity for all 3 tasks. Motion smoothness and idle time also showed validity for tasks involving bimanual coordination and tasks requiring a more tactical approach, respectively. Additionally, motion smoothness and average speed showed a high internal consistency, proving them to be the most task-independent of all the metrics analyzed.
  
  
  CONCLUSIONS
  Motion metrics are complementary and valid for assessing basic psychomotor skills, and their relevance depends on the skill being evaluated. A larger clinical implementation, combined with quality performance information, will give more insight on the relevance of the results shown in this study.
authors.affiliation: Universidad Politécnica de Madrid (UPM), Madrid, Spain. ioropesa@gbt.tfo.upm.es
authors.forename: Ignacio
authors.initials: I
authors.lastname: Oropesa
authors.forename: Magdalena K
authors.initials: MK
authors.lastname: Chmarra
authors.forename: Patricia
authors.initials: P
authors.lastname: Sánchez-González
authors.forename: Pablo
authors.initials: P
authors.lastname: Lamata
authors.forename: Sharon P
authors.initials: SP
authors.lastname: Rodrigues
authors.forename: Silvia
authors.initials: S
authors.lastname: Enciso
authors.forename: Francisco M
authors.initials: FM
authors.lastname: Sánchez-Margallo
authors.forename: Frank-Willem
authors.initials: FW
authors.lastname: Jansen
authors.forename: Jenny
authors.initials: J
authors.lastname: Dankelman
authors.forename: Enrique J
authors.initials: EJ
authors.lastname: Gómez
mesh_terms: D004521:Educational Measurement / Q000379:methods*; D006801:Humans; D010535:Laparoscopy / Q000193:education*; D009068:Movement; D011597:Psychomotor Performance; D015203:Reproducibility of Results; D018709:Statistics, Nonparametric; D013647:Task Performance and Analysis