False-Positive Rates and Associated Factors on the Vestibular/Ocular Motor Screening (VOMS) Using the Military Acute Concussion Evaluation 2 (MACE 2) Cutoffs in U.S. Military Personnel

Objective: This study examined false-positive rates and associated factors on the Vestibular/Ocular Motor Screening (VOMS) in healthy US Army Special Operations Command (USASOC) personnel using the symptom provocation cutoff of ≥1 for any VOMS item as recommended in the Military Acute Concussion Evaluation 2 (MACE 2). Setting: Military site. Participants: Active-duty USASOC personnel aged 18 to 40 years with 20/20 vision, no duty limitations, and no recent concussion. Participants were excluded if they had a history of vestibular or neurologic disorder, only monocular vision capabilities, or previous moderate-to-severe traumatic brain injury. Four hundred and sixteen USASOC personnel were enrolled; 402 were analyzed. Design: This was a cross-sectional study of diagnostic accuracy. Trained research personnel administered the VOMS. Participants and research personnel were not blinded. Main Measures: False-positive rates and associated risk factors on the VOMS. Results: Among 402 healthy participants (mean age 28.5 ± 5.7 years), 35.1% had at least one false positive on the VOMS. Twenty-two percent had at least one false-positive change score, 12.2% had a near-point convergence (NPC) distance ≥5 cm, and 4.2% had both. VOMS false positives on each VOMS item ranged from 4.7% to 15.7%. Participants with ≥1 false positive on the VOMS were more likely to have a motion sickness history (OR = 2.35, 95% CI = 1.35-4.12, P = .003) or a concussion history (OR = 1.97, 95% CI = 1.27-3.05, P = .002). Conclusion: The MACE 2 cutoff resulted in a higher overall rate of at least one false positive across items (35.1%) in this sample of healthy USASOC personnel compared to prior total score cutoffs. Consistent with previous research, a history of motion sickness or concussion was associated with an increased likelihood of false positives. Multivariate predictors included motion sickness and a history of concussion. Military medical providers should consider motion sickness, history of concussion, and performance on individual VOMS items.