For most collegiate athletes, normative reference data match or outperform individualized baselines for acute concussion diagnosis; baseline testing adds little diagnostic value.

Background

Preseason baseline testing is widely recommended for concussion management, but its added diagnostic value over normative reference values is uncertain. This study quantified the diagnostic benefit of baseline testing versus normative data and identified which athletes, if any, benefit most from baseline-informed diagnosis.

Patients

• NCAA collegiate athletes from the CARE Consortium (2014–2020)
• Included: 1081 athletes (43.9% female); 1279 acute (24–48 h) concussion assessments; 1551 reference (baseline/rebaseline) assessments
• Prior concussions: 0 (41.6%), 1 (39.4%), 2 (12.1%), ≥3 (5.6%)
• Race/Ethnicity: White (68.6%), African American (15.5%), Multiple races (9.5%); Non-Hispanic (80.9%), Hispanic (8.3%)
• Common medical histories: Depression (1.9%), Learning disorder (1.9%), Non-migraine headache (1.8%)

Intervention

Acute concussion prediction using change scores derived from each athlete’s individualized preseason (or 6-month rebaseline) data across a multimodal battery (SAC, SCAT3 symptom severity, BESS, ImPACT composites). Modeled via multivariable logistic regression (PM-BL).

Control

Acute concussion prediction using change scores referenced to population-based normative values for the same battery, without individualized baselines. Modeled via multivariable logistic regression (PM-NRV).

Outcome

• Primary: Diagnostic performance (AUC) of baseline-based vs normative-based models
• Secondary:
  • Sensitivity and specificity at a prespecified threshold (weighted 60% sensitivity, 40% specificity)
  • Distribution of the Diagnostic Utility of Baseline testing (DUB: −1, 0, +1) at the assessment level
  • Subgroup differences in DUB by demographics and medical history

Study Design

Cohort study (diagnostic). Leave-one-athlete-out cross-validation to evaluate model generalizability.

Level of Evidence

Level 2 (diagnostic cohort).

Follow up period

Acute assessments at 24–48 hours post-injury; preseason and 6-month post–return-to-play assessments used as reference baselines.

Results

Primary outcome

• AUC: Baseline model (PM-BL) 0.89 vs Normative model (PM-NRV) 0.90 (very similar performance)

Secondary outcomes

• Sensitivity/Specificity (at weighted threshold):
  • PM-BL: Sensitivity 0.85; Specificity 0.87
  • PM-NRV: Sensitivity 0.87; Specificity 0.77
• DUB distribution across 1279 acute assessments:
  • DUB = 0 (same diagnosis with baseline and normative): 86.7%
  • DUB = −1 (baseline would miss concussion that norms detect): 7.5%
  • DUB = +1 (baseline improves over norms): 5.8%
• Subgroups more often correctly identified as concussed using norms (i.e., more DUB = −1 when using baselines):
  • Hispanic ethnicity
  • History of psychiatric disorders
  • History of depression
• Additional small distribution differences by sex and by number of prior concussions were observed.
• NNT: Not applicable (diagnostic accuracy study without dichotomous treatment outcomes).

Limitations

• Restricted to NCAA athletes; generalizability to high school, professional, or military populations is uncertain.
• Model included BESS, SAC, SCAT3 symptom checklist, and ImPACT only; findings may differ with other tools (e.g., VOMS, BSI-18) or raw post-injury scores.
• Some subgroups (e.g., psychiatric, ADHD, balance disorders) were small; medication status (e.g., for ADHD) not fully accounted for.
• Normative values were general collegiate norms; sport- or team-specific norms might yield different results.
• DUB depends on diagnostic threshold selection, though overall conclusions were robust in sensitivity analyses.

Funding

• NCAA–Department of Defense Grand Alliance CARE Consortium
• Agency for Healthcare Research and Quality (AHRQ), HHS: R03HS029422
• Office of the Assistant Secretary of Defense for Health Affairs (Psychological Health/Traumatic Brain Injury Program), DoD: W81XWH-14-2-0151
• US Army Medical Research Acquisition Activity served as awarding/administering office
• Authors’ interpretations do not necessarily represent views of the Department of Defense

Citation

Pandey HS, Lahijanian B, Schmidt JD, Lynall RC, Broglio SP, McAllister TW, McCrea MA, Pasquina PF, Garcia GGP, and the CARE Consortium Investigators. Quantifying the Diagnostic Utility of Baseline Testing in Concussion Management: An Analysis of Collegiate Athletes From the NCAA-DoD CARE Consortium Dataset. The American Journal of Sports Medicine. 2025;53(1):181–191. doi:10.1177/03635465241296868.