The balance error scoring system (BESS) is a human-scored, field-based balance test used in cases of suspected concussion. Recently developed instrumented alternatives to human scoring carry substantial advantages over traditional testing, but thus far report relatively abstract outcomes that may not be useful to clinicians or coaches. In contrast, the automated assessment of postural stability (AAPS) is a computerized system that tabulates error events in accordance with the original description of the BESS. This study compared AAPS and human-based BESS scores. A total of 25 healthy adults performed the modified BESS. Tests were scored twice each by 3 human raters and the computerized system. Interrater (between human) and intermethod (AAPS vs human) agreement (interclass correlation coefficient2,1) were calculated alongside Bland–Altman limits of agreement. Interrater analyses were significant (P < .01) and demonstrated good to excellent agreement. Intermethod agreement analyses were significant (P < .01), with agreement ranging from poor to excellent. Computerized scores were equivalent across rating occasions. Limits of agreement ranges for AAPS versus the human average exceeded the average limits of agreement ranges between human raters. Coaches and clinicians may consider a system such as AAPS to automate balance testing while maintaining the familiarity of human-based scoring, although scores should not yet be considered interchangeable with those of a human rater.
Stephen M. Glass, Alessandro Napoli, Elizabeth D. Thompson, Iyad Obeid, and Carole A. Tucker
Stephen M. Glass, Christopher K. Rhea, Matthew W. Wittstein, Scott E. Ross, John P. Florian, and F.J. Haran
Transitioning between different sensory environments is known to affect sensorimotor function and postural control. Water immersion presents a novel environmental stimulus common to many professional and recreational pursuits, but is not well-studied with regard to its sensorimotor effects upon transitioning back to land. The authors investigated the effects of long-duration water immersion on terrestrial postural control outcomes in veteran divers. Eleven healthy men completed a 6-hour thermoneutral pool dive (4.57 m) breathing diver air. Center of pressure was observed before and 15 minutes after the dive under 4 conditions: (1) eyes open/stable surface (Open-Stable); (2) eyes open/foam surface (Open-Foam); (3) eyes closed/stable surface (Closed-Stable); and (4) eyes closed/foam surface (Closed-Foam). Postdive decreases in postural sway were observed in all testing conditions except for Open-Stable. The specific pattern of center of pressure changes in the postdive window is consistent with (1) a stiffening/overregulation of the ankle strategy during Open-Foam, Closed-Stable, and Closed-Foam or (2) acute upweighting of vestibular input along with downweighting of somatosensory, proprioceptive, and visual inputs. Thus, our findings suggest that postimmersion decreases in postural sway may have been driven by changes in weighting of sensory inputs and associated changes in balance strategy following adaptation to the aquatic environment.