Samuel R Walton1,2, Donna K Broshek3, Jason R Freeman4, Jay Hertel1, J Patrick Meyer5,6, Nicholas K Erdman1, Jacob E Resch1. 1. Department of Kinesiology, University of Virginia, Charlottesville, VA 22903, USA. 2. Department of Exercise and Sport Science, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA. 3. Department of Psychiatry and Neurobehavioral Sciences, University of Virginia School of Medicine, Charlottesville, VA 22903, USA. 4. Department of Athletics, Sports Psychology, University of Virginia, Charlottesville, VA 22903, USA. 5. Department of Leadership, Foundations and Policy, University of Virginia, Charlottesville, VA 22903, USA. 6. Northwest Evaluation Association, Portland, OR 97209, USA.
Abstract
OBJECTIVE: The necessity for pre-injury baseline computerized neurocognitive assessments versus comparing post-concussion outcomes to manufacturer-provided normative data is unclear. Manufacturer-provided norms may not be equivalent to institution-specific norms, which poses risks for misclassifying the presence of impairment when comparing individual post-concussion performance to manufacturer-provided norms. The objective of this cohort study was to compare institutionally derived normative data to manufacturer-provided normative values provided by ImPACT® Applications, Incorporated. METHOD: National Collegiate Athletic Association Division 1 university student athletes (n = 952; aged 19.2 ± 1.4 years, 42.5% female) from one university participated in this study by completing pre-injury baseline Immediate Post-Concussion Assessment and Cognitive Test (ImPACT) assessments. Participants were separated into 4 groups based on ImPACT's age and gender norms: males <18 years old (n = 186), females <18 years old (n = 165), males >19 years old (n = 361) or females >19 years old (n = 240). Comparisons were made between manufacturer-provided norms and institutionally derived normative data for each of ImPACT's clinical composite scores: Verbal (VEM) and Visual (VIM) Memory, Visual Motor Speed (VMS), and Reaction Time (RT). Outcome scores were compared for all groups using a Chi-squared goodness of fit analysis. RESULTS: Institutionally derived normative data indicated above average performance for VEM, VIM, and VMS, and slightly below average performance for RT compared to the manufacturer-provided data (χ2 ≥ 20.867; p < 0.001). CONCLUSIONS: Differences between manufacturer- and institution-based normative value distributions were observed. This has implications for an increased risk of misclassifying impairment following a concussion in lieu of comparison to baseline assessment and therefore supports the need to utilize baseline testing when feasible, or otherwise compare to institutionally derived norms rather than manufacturer-provided norms.
OBJECTIVE: The necessity for pre-injury baseline computerized neurocognitive assessments versus comparing post-concussion outcomes to manufacturer-provided normative data is unclear. Manufacturer-provided norms may not be equivalent to institution-specific norms, which poses risks for misclassifying the presence of impairment when comparing individual post-concussion performance to manufacturer-provided norms. The objective of this cohort study was to compare institutionally derived normative data to manufacturer-provided normative values provided by ImPACT® Applications, Incorporated. METHOD: National Collegiate Athletic Association Division 1 university student athletes (n = 952; aged 19.2 ± 1.4 years, 42.5% female) from one university participated in this study by completing pre-injury baseline Immediate Post-Concussion Assessment and Cognitive Test (ImPACT) assessments. Participants were separated into 4 groups based on ImPACT's age and gender norms: males <18 years old (n = 186), females <18 years old (n = 165), males >19 years old (n = 361) or females >19 years old (n = 240). Comparisons were made between manufacturer-provided norms and institutionally derived normative data for each of ImPACT's clinical composite scores: Verbal (VEM) and Visual (VIM) Memory, Visual Motor Speed (VMS), and Reaction Time (RT). Outcome scores were compared for all groups using a Chi-squared goodness of fit analysis. RESULTS: Institutionally derived normative data indicated above average performance for VEM, VIM, and VMS, and slightly below average performance for RT compared to the manufacturer-provided data (χ2 ≥ 20.867; p < 0.001). CONCLUSIONS: Differences between manufacturer- and institution-based normative value distributions were observed. This has implications for an increased risk of misclassifying impairment following a concussion in lieu of comparison to baseline assessment and therefore supports the need to utilize baseline testing when feasible, or otherwise compare to institutionally derived norms rather than manufacturer-provided norms.
Authors: Landon B Lempke; Robert C Lynall; Melissa N Anderson; Michael A McCrea; Thomas W McAllister; Steven P Broglio; Julianne D Schmidt Journal: Sports Med Date: 2021-06-15 Impact factor: 11.136