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A Normative Reference vs. Baseline Testing Compromise for ImPACT: The CARE Consortium Multiple Variable Prediction (CARE-MVP) Norms

A Correction to this article was published on 03 March 2020

This article has been updated



Sports medicine clinicians routinely use computerized neurocognitive testing in sport-related concussion management programs. Debates continue regarding the appropriateness of normative reference comparisons versus obtaining individual baseline assessments, particularly for populations with greater likelihood of having below- or above-average cognitive abilities. Improving normative reference methods could offer alternatives to perceived logistical and financial burdens imposed by universal baseline testing.


To develop and validate the Concussion Assessment, Research, and Education (CARE) Consortium Multiple Variable Prediction (MVP) norms for the Immediate Postconcussion Assessment and Cognitive Testing (ImPACT).


We developed the CARE-MVP norms for ImPACT composite scores using regression-based equations. Predictor variables included sex, race (white/Caucasian, black/African American, Asian, or Multiple Races), medical history [attention-deficit/hyperactivity disorder (ADHD), learning disorder (LD), prior concussion(s), prior psychiatric diagnosis], and an estimate of premorbid intellect (Wechsler Test of Adult Reading). CARE-MVP norms were first validated in an independent sample of healthy collegiate athletes by comparing predicted and actual baseline test scores using independent-samples t-tests and Cohen’s d effect sizes. We then evaluated base rates of low scores in athletes self-reporting ADHD/LD (vs. non-ADHD/LD) and black/African American race (vs. white/Caucasian) across multiple normative reference methods (Chi square, Cramer’s V effect size). Lastly, we validated the CARE-MVP norms in a concussed sample (dependent samples t test, Cohen’s d effect size).


A total of 5233 collegiate athletes (18.8 ± 1.2 years, 70.5% white/Caucasian, 39.1% female) contributed to the CARE-MVP norms (development N = 2616; internal validation N = 2617). Race and WTAR score were the strongest and most consistent ImPACT score predictors. There were negligible mean differences between observed and predicted (CARE-MVP) baseline scores (Cohen’s d < 0.1) for all ImPACT composite scores except Reaction Time (predicted ~ 20 ms faster than observed, d = − 0.28). Low score base rates were similar for athletes across subpopulations when using CARE-MVP norms (ADHD/LD, V = 0.017–0.028; black/African American, V = 0.043–0.053); while, other normative reference methods resulted in disproportionately higher rates of low scores (ADHD/LD, V = 0.062–0.101; black/African American race, V = 0.163–0.221). Acute (24–48 h) postconcussion ImPACT scores were significantly worse than CARE-MVP norms but notably varied as a function of concussion symptom severity.


Results support CARE-MVP norm use in populations typically underrepresented or not adjusted for in traditional normative reference samples, such as those self-reporting ADHD/LD or black/African American race. CARE-MVP norms improve upon prior normative methods and may offer a practical, simple alternative for collegiate institutions concerned about logistical and financial burden associated with baseline testing. An automated scoring program is provided.

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Data Availability Statement

Data from the CARE Consortium are publicly available within the Federal Interagency Traumatic Brain Injury Research (FITBIR) informatics system (

Change history

  • 03 March 2020

    Unfortunately, in the published article the symbol “% ile” has incorrectly been published as “‰”. We have now corrected this in all the occurrences.


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We thank student-athletes across the CARE Consortium for their willingness to participate in research. We also thank Drs. Jeffrey Bazarian (University of Rochester), Sara Chrisman (University of Washington), Jonathan Jackson (United States Air Force Academy), Gerald McGinty (United States Air Force Academy), Patrick O’Donnell (United States Coast Guard Academy), April Reed (Azusa Pacific University), Diane Langford (Temple University), and Brian Dykhuizen (Wilmington College) for contributing data to this study. Care Consortium Investigators: Holly Benjamin, MD (Department of Rehabilitation Medicine and Pediatrics, University of Chicago). Alison Brooks, MD, MPH (Department of Orthopedics, University of Wisconsin, Madison). Thomas Buckley, PhD (Department of Kinesiology & Applied Physiology, University of Delaware). Kenneth Cameron, PhD, MPH, ATC (Keller Army Hospital, United States Military Academy). Luis Feigenbaum, DPT, ATC (Department of Physical Therapy, Miller School of Medicine, University of Miami). Christopher Giza, MD (Department of Pediatrics, University of California, Los Angeles). Joseph Hazzard, Jr., PhD, ATC (Department of Exercise Science, Bloomsburg University). Thomas Kaminsky, PhD, ATC (Department of Kinesiology & Applied Physiology, University of Delaware). Louise Kelly, PhD (Department of Exercise Science, California Lutheran University). Anthony Kontos, PhD (Department of Orthopaedic Surgery, University of Pittsburgh). Christina Master, MD (Division of Orthopedics, Children’s Hospital of Philadelphia). Christopher Miles, MD (Department of Family and Community Medicine, Wake Forest University). Jessica Miles, PhD (Department of Kinesiology, University of North Georgia). Justus Ortega, PhD (Department of Kinesiology & Recreation Administration, Humboldt State University). Nicholas Port, PhD (School of Optometry, Indiana University). Margot Putukian, MD (Athletic Medicine, Princeton University).

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Correspondence to Breton M. Asken.

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BMA, ZMH, JDS, RMB, SPB, MAM, TWM, and JRC declare no conflicts of interest related to the content of this study. This publication was supported in part by the Grand Alliance Concussion Assessment, Research, and Education Consortium, which receives funding from the National Collegiate Athletic Association and the Department of Defense. The US Army Medical Research Acquisition Activity is the awarding and administering acquisition office. This work was supported by the Office of the Assistant Secretary of Defense for Health Affairs through the Psychological Health and Traumatic Brain Injury Program (award W81XWH-14-2-0151). Opinions, interpretations, conclusions, and recommendations are those of the authors and are not necessarily endorsed by the Department of Defense (Defense Health Program funds).

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the original article has been corrected. Due to "%ile" symbol error

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Asken, B.M., Houck, Z.M., Schmidt, J.D. et al. A Normative Reference vs. Baseline Testing Compromise for ImPACT: The CARE Consortium Multiple Variable Prediction (CARE-MVP) Norms. Sports Med 50, 1533–1547 (2020).

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