False-Positive Rates and Associated Risk Factors on the Vestibular-Ocular Motor Screening and Modified Balance Error Scoring System in US Military Personnel

Abstract

Context: In 2018, the US military developed the Military Acute Concussion Evaluation-2 (MACE-2) to inform the acute evaluation of mild traumatic brain injury (mTBI). However, researchers have yet to investigate false-positive rates for components of the MACE-2, including the Vestibular-Ocular Motor Screening (VOMS) and modified Balance Error Scoring System (mBESS), in military personnel.

Objective: To examine factors associated with false-positive results on the VOMS and mBESS in US Army Special Operations Command (USASOC) personnel.

Design: Cross-sectional study.

Setting: Military medical clinic.

Patients or other participants: A total of 416 healthy USASOC personnel completed the medical history, VOMS, and mBESS evaluations.

Main outcome measure(s): False-positive rates for the VOMS (≥2 on VOMS symptom items, >5 cm for near point of convergence [NPC] distance) and mBESS (total score >4) were determined using χ2 analyses and independent-samples t tests. Multivariable logistic regressions (LRs) with adjusted odds ratios (aORs) were performed to identify risk factors for false-positive results on the VOMS and mBESS. The VOMS item false-positive rates ranged from 10.6% (smooth pursuits) to 17.5% (NPC). The mBESS total score false-positive rate was 36.5%.

Results: The multivariable LR model supported 3 significant predictors of VOMS false-positives, age (aOR = 1.07; 95% CI = 1.02, 1.12; P = .007), migraine history (aOR = 2.49; 95% CI = 1.29, 4.81; P = .007), and motion sickness history (aOR = 2.46; 95% CI = 1.34, 4.50; P = .004). Only a history of motion sickness was a significant predictor of mBESS false-positive findings (aOR = 2.34; 95% CI = 1.34, 4.05; P = .002).

Conclusions: False-positive rates across VOMS items were low and associated with age and a history of mTBI, migraine, or motion sickness. False-positive results for the mBESS total score were higher (36.5%) and associated only with a history of motion sickness. These risk factors for false-positive findings should be considered when administering and interpreting VOMS and mBESS components of the MACE-2 in this population.

Keywords: Military Acute Concussion Evaluation-2; concussion; mild traumatic brain injury.