title: Limitations of haptic feedback devices on construct validity of the LapSim® virtual reality simulator.
abstract: BACKGROUND
  Surgeons performing laparoscopy need a high degree of psychomotor skills, which can be trained and assessed on virtual reality (VR) simulators. VR simulators simulate the surgical environment and assess psychomotor skills according to predefined parameters. This study aimed to validate a proficiency-based training setup that consisted of two tasks with predefined threshold values and handles with haptic feedback on the LapSim(®) VR simulator. The two tasks have been found to have construct validity in previous studies using handles without haptic feedback.
  
  
  METHODS
  The participants were divided into three groups: novices (0-50 laparoscopic procedures), intermediates (51-300 laparoscopic procedures), and experts (more than 300 procedures). It was assumed that psychomotor skills increase with experience. All participants conducted the tasks lifting and grasping and fine dissection 20 times each. Validity of the training setup was investigated by comparing the number of times each participant passed a predefined threshold level for a set of 19 parameters.
  
  
  RESULTS
  Construct validity was established for one parameter; "misses on right side" on the lifting and grasping task, whereas the other 18 parameters did not show construct validity.
  
  
  CONCLUSIONS
  The setup employed in this study failed to establish construct validity for more than one parameter. This indicates that the simulation of haptic feedback influences the training performance on laparoscopic simulators and is an important part of validating a training setup. A haptic device should generate haptic sensations in a realistic manner, without introducing frictional forces that are not inherent to laparoscopy.
authors.affiliation: Department of Medical Technology, SINTEF Technology and Society, PB 4760, Sluppen, 7465, Trondheim, Norway. cecilie.vapenstad@sintef.no
authors.forename: Cecilie
authors.initials: C
authors.lastname: Våpenstad
authors.forename: Erlend Fagertun
authors.initials: EF
authors.lastname: Hofstad
authors.forename: Lars Eirik
authors.initials: LE
authors.lastname: Bø
authors.forename: Magdalena Karolina
authors.initials: MK
authors.lastname: Chmarra
authors.forename: Esther
authors.initials: E
authors.lastname: Kuhry
authors.forename: Gjermund
authors.initials: G
authors.lastname: Johnsen
authors.forename: Ronald
authors.initials: R
authors.lastname: Mårvik
authors.forename: Thomas
authors.initials: T
authors.lastname: Langø
mesh_terms: D000328:Adult; D003198:Computer Simulation; D004867:Equipment Design; D005246:Feedback; D005260:Female; D006801:Humans; D020706:Laparoscopes; D008297:Male; D015203:Reproducibility of Results; D014110:Touch