title: Does tester experience influence the reliability with which 3D gait kinematics are collected in healthy adults?
abstract: OBJECTIVE
  To determine whether tester experience influences the reliability of three-dimensional gait collections.
  
  
  METHODS
  Reliability study.
  
  
  METHODS
  Ten healthy subjects visited a university gait laboratory on two separate days and underwent a walking gait analysis. During each visit, kinematic data were collected by a biomechanist with 8 years of 3D gait analysis experience (EXP) and a physical therapist with no previous 3D gait analysis experience (NOV).
  
  
  METHODS
  Joint kinematic angles were calculated using either a functional or predictive joint identification method. Within-tester and between-tester measures of reliability were determined by calculating the root mean square error (RMS) and coefficient of multiple correlations (CMC).
  
  
  RESULTS
  Within-tester RMS and CMC values were not significantly different (P > 0.05) between the EXP and NOV testers using either a functional or predictive joint approach. Within-tester CMC values exceeded 0.90 for both testers across all kinematic variables. Between-tester CMC reliability values were greater than 0.85 for all variables measured.
  
  
  CONCLUSIONS
  Following basic training, a physiotherapy clinician with no previous 3D gait experience is as reliable as an experienced gait biomechanist with respect to marker placement accuracy. In addition, reliability comparisons between an experienced and novice tester appear independent of the joint identification method chosen.
authors.affiliation: Faculty of Kinesiology, Running Injury Clinic, University of Calgary, 2500 University Dr. NW, Calgary, AB T2N 1N4, Canada. Electronic address: rjleigh@ucalgary.ca.
authors.forename: Ryan J
authors.initials: RJ
authors.lastname: Leigh
authors.affiliation: Department of Kinesiology and Health Promotion, University of Kentucky, Lexington, KY, USA. Electronic address: michael.pohl@uky.edu.
authors.forename: Michael B
authors.initials: MB
authors.lastname: Pohl
authors.affiliation: Faculty of Kinesiology, Running Injury Clinic, University of Calgary, 2500 University Dr. NW, Calgary, AB T2N 1N4, Canada; Faculty of Nursing, University of Calgary, Calgary, Alberta, Canada. Electronic address: rferber@ucalgary.ca.
authors.forename: Reed
authors.initials: R
authors.lastname: Ferber
mesh_terms: D056352:Athletes; D001696:Biomechanical Phenomena; D005080:Exercise Test / Q000379:methods*; D005260:Female; D005684:Gait / Q000502:physiology*; D064368:Healthy Volunteers; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D007719:Knee Joint / Q000502:physiology*; D016059:Range of Motion, Articular / Q000502:physiology*; D015203:Reproducibility of Results; D014741:Video Recording; D055815:Young Adult
keywords: Gait analysis; Kinematics; Reliability; Walking