1. Acute Assessment of Mild Traumatic Brain Injury with the King-Devick Test in an Emergency Department Sample
Objectives
Results
The MTBI and trauma control were well-matched on age and education, but the former contained a somewhat higher proportion of males (73% vs 52% ; chi2=3.71, p=.054).
Group differences on the clinical tests are presented in the Table. In summary:
Post Concussion Symptom Scale: Yes
SAC: Yes
The K-D test: No
In logistic regression with group membership (MTBI vs. trauma control) as the dichotomous outcome:
Entering SAC and Symptom Score as predictors achieved good discrimination (chi2=19.2, p<0.001, Nagelkerke R2=0.398, area under the Receiver Operating Characteristic Curve=0.827).
Adding the K-D test did not contribute incrementally (p=0.191).
Low K-D scores in the MTBI group (<1 standard deviation below trauma controls) were not associated with loss of consciousness or traumatic abnormalities on magnetic resonance imaging, suggesting that these cases may have been false positives.
The King-Devick Test (K-D) is a brief measure of cognitive processing speed and rapid gaze shifting that appears sensitive to the acute effects of sport-related concussion.
The present study aimed to evaluate its diagnostic and incremental validity in civilian trauma patients with mild traumatic brain injury (MTBI).
Methods
Participants:
patients with MTBI, n=26, and
trauma controls with non-head injuries, n=33.
Emergency Department of Tampere University Hospital.
World Health Organization’s MTBI criteria were applied.
Nine exclusion criteria were used to rule out pre-existing medical conditions or other confounding factors.
The patients and controls underwent a clinical evaluation that included:
the K-D test and
previously validated assessment tools for MTBI that are part of the Sport Concussion Assessment Tool (editions 2 & 3):
the Post Concussion Symptom Scale, and
the Standardized Assessment of Concussion (SAC).
The patients with MTBI were assessed at an average of 31 hours post-injury (range=4-72h).
Magnetic resonance imaging (3 Tesla) was also conducted within 10 days hospital discharge.
Table. Descriptive statistics and mean comparisons for the King-Devick Test® and Sport Concussion Assessment Tool components.
Mean (SD)
MTBI
Controls F p
Cohen’s d
K-D Test Trial 1
58.86 (16.21)
52.70 (11.95)
2.64
0.110
0.43
K-D Test Trial 2
51.68 (12.09)
47.15 (10.06)
2.28
0.137
0.41
Best K-D Test Score
51.50 (12.16)
47.09 (10.00)
2.16
0.148
0.40
Symptom Score
14.14 (6.03)
19.21 (3.56)
15.43
<0.001
1.02
Symptom Severity Score
16.50 (14.43)
3.79 (5.96)
21.11
1.15
SAC
26.00 (2.29)
27.67 (1.81)
9.025
0.004
0.81
M-BESS
21.58 (7.02)
19.61 (6.81)
0.988
0.325
0.29
Conclusion
The present findings do not support the K-D test for the assessment of civilian trauma MTBI in an Emergency Department setting.
Its utility may depend on the availability of pre-injury baseline testing and feasibility of more rapid (<1 hour) post-injury testing.
Noah D. Silverberg
PhD1
Teemu M. Luoto
MD2
Juha Öhman
MD, PhD2
Grant L. Iverson
PhD3
1Division of Physical Medicine & Rehabilitation, University of British Columbia; & GF Strong Rehab Centre, Vancouver, BC, Canada
2Department of Neurosciences and Rehabilitation, Tampere University Hospital, Tampere, Finland
3Department of Physical Medicine and Rehabilitation, Harvard Medical School; & Red Sox Foundation and Massachusetts General Hospital Home Base Program, Boston, MA, USA
For
more
info and contacts: