title: Test-retest consistency of a postural sway assessment protocol for adolescent athletes measured with a force plate.
abstract: OBJECTIVE
  Postural control assessments can provide a powerful means of detecting concussion-related neurophysiological abnormalities and are considered an important part of the concussion management processes. Studies with college athletes indicate that postural sway analyzed using complexity metrics may provide a sensitive and novel way to detect post-concussion postural control impairments. The purpose of this study was to determine if a postural sway assessment protocol (PSAP) measured using a force plate system can serve as a reliable assessment tool for adolescent athletes.
  
  
  METHODS
  The short-term and long-term test-retest reliability of the PSAP was examined in a group of adolescent female athletes under eyes open and eyes closed conditions. Detrended fluctuation analysis was used to evaluate the complexity of the times series data (i.e., degree of self-similarity across time scales). Conventional measures of standard deviation and total path length (distance traveled by the center-of-pressure) were also assessed.
  
  
  RESULTS
  The complexity and conventional measures generally demonstrated good reliability coefficients for short-term and long-term test-retest reliability with both eyes open and eyes closed conditions. Intra-class Correlation Coefficient (ICC) values ranged from .38-.90 The highest ICC values corresponded with the short-term reliability for the eyes open condition, while the lower ICC values corresponded with the long-term reliability for the eyes closed condition.
  
  
  CONCLUSIONS
  The results of this study indicate that the PSAP demonstrated good short-term and long-term test-retest reliability. In addition, no evidence of learning effects was elicited through this study. Future studies should further explore the validity and feasibility of the use of this protocol for different age groups, different types of athletes, and longitudinal evaluations of post-concussion impairments.
  
  
  CONCLUSIONS
  This study provides preliminary support for the utility of a postural sway assessment protocol measured using a force plate for use with adolescent athletes.
  
  
  METHODS
  Level III.
authors.forename: Catherine C
authors.initials: CC
authors.lastname: Quatman-Yates
authors.affiliation: Division of Occupational and Physical Therapy, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.
authors.forename: Aaron
authors.initials: A
authors.lastname: Lee
authors.forename: Jason A
authors.initials: JA
authors.lastname: Hugentobler
authors.affiliation: Physical Medicine and Rehabilitation, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.
authors.forename: Brad G
authors.initials: BG
authors.lastname: Kurowski
authors.forename: Gregory D
authors.initials: GD
authors.lastname: Myer
authors.affiliation: University of Cincinnati, Department of Psychology, Center for Cognition, Action and Perception, Cincinnati, OH, USA.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Riley
keywords: concussion; force plate; postural control; reliability