Diane M Wrisley

The Balance Evaluation Systems Test (BESTest) to Differentiate Balance Deficits

Background: Current clinical balance assessment tools do not aim to help therapists identify the underlying postural control systems responsible for poor functional balance. By identifying the disordered systems underlying balance control, therapists can direct specific types of intervention for different types of balance problems. Objective: The goal of this study was to develop a clinical balance assessment tool that aims to target 6 different balance control systems so that specific rehabilitation approaches can be designed for different balance deficits. This article presents the theoretical framework, interrater reliability, and preliminary concurrent validity for this new instrument, the Balance Evaluation Systems Test (BESTest). Design: The BESTest consists of 36 items, grouped into 6 systems: “Biomechanical Constraints,” “Stability Limits/Verticality,” “Anticipatory Postural Adjustments,” “Postural Responses,” “Sensory Orientation,” and “Stability in Gait.” Methods: In 2 interrater trials, 22 subjects with and without balance disorders, ranging in age from 50 to 88 years, were rated concurrently on the BESTest by 19 therapists, students, and balance researchers. Concurrent validity was measured by correlation between the BESTest and balance confidence, as assessed with the Activities-specific Balance Confidence (ABC) Scale. Results: Consistent with our theoretical framework, subjects with different diagnoses scored poorly on different sections of the BESTest. The intraclass correlation coefficient (ICC) for interrater reliability for the test as a whole was .91, with the 6 section ICCs ranging from .79 to .96. The Kendall coefficient of concordance among raters ranged from .46 to 1.00 for the 36 individual items. Concurrent validity of the correlation between the BESTest and the ABC Scale was r=.636, P<.01. Limitations: Further testing is needed to determine whether: (1) the sections of the BESTest actually detect independent balance deficits, (2) other systems important for balance control should be added, and (3) a shorter version of the test is possible by eliminating redundant or insensitive items. Conclusions: The BESTest is easy to learn to administer, with excellent reliability and very good validity. It is unique in allowing clinicians to determine the type of balance problems to direct specific treatments for their patients. By organizing clinical balance test items already in use, combined with new items not currently available, the BESTest is the most comprehensive clinical balance tool available and warrants further development.

Is perception of handicap related to functional performance in persons with vestibular dysfunction

Objective: The purpose of this study was to determine if scores between 0 and 30 (mild), 31 and 60 (moderate), and 61 and 100 (severe) on the Dizziness Handicap Inventory (DHI) differentiated a person’s functional abilities. Study Design: Retrospective case series. Setting: Tertiary balance outpatient center. Patients: Patients (n = 85; mean age, 61 years) with a variety of vestibular diagnoses participated. Interventions: Patients completed the DHI, the Dynamic Gait Index (DGI), the 5 times sit to stand test (FTSST), the Activities-specific Balance Confidence (ABC) scale, gait speed, and the Timed “Up & Go” (TUG) during the same session. Reported numbers of falls within the last 4 weeks were recorded. Main Outcome Measures: The DGI, FTSST, ABC, gait speed, TUG, and gait speed were compared among DHI groups. Results: Significant differences were identified using an analysis of variance between DHI groups on the DGI, the FTSST, ABC, and number of falls (p < 0.05). A significant difference was found between DHI groups (mild vs. severe and moderate vs. severe) on the DGI (p < 0.05) with greater DHI scores exhibiting more impaired walking. The FTSST was different between DHI groups mild and severe and DHI groups moderate and severe (p < 0.05), with slower FTSST scores with higher DHI scores. Reported falls were higher among the severe DHI group and the other 2 DHI groups (p < 0.05). All 3 DHI groupings were different from each other on the ABC (p < 0.001). Conclusion: Patients who perceive a greater handicap as a result of dizziness demonstrate greater functional impairment than patients who perceive less handicap from dizziness.

Reliability of the dynamic gait index in people with vestibular disorders

OBJECTIVEnTo examine the interrater reliability of the Dynamic Gait Index (DGI) when used with patients with vestibular disorders and with previously published instructions.nnnDESIGNnCorrelational study.nnnSETTINGnOutpatient physical therapy clinic.nnnPARTICIPANTSnSubjects included 30 patients (age range, 27-88y) with vestibular disorders, who were referred for vestibular rehabilitation.nnnINTERVENTIONSnSubjects performance on the DGI was concurrently rated by 2 physical therapists experienced in vestibular rehabilitation to determine interrater reliability.nnnMAIN OUTCOME MEASURESnPercentage agreement, kappa statistics, and the ratio of subject variability to total variability were calculated for individual DGI items. Kappa statistics for individual items were averaged to yield a composite kappa score of the DGI. Total DGI scores were evaluated for interrater reliability by using the Spearman rank-order correlation coefficient.nnnRESULTSnInterrater reliability of individual DGI items varied from poor to excellent based on kappa values (kappa range,.35-1.00). Composite kappa values showed good overall interrater reliability (kappa=.64) of total DGI scores. The Spearman rho demonstrated excellent correlation (r=.95) between total DGI scores given concurrently by the 2 raters.nnnCONCLUSIONnDGI total scores, administered by using the published instructions, showed moderate interrater reliability with subjects with vestibular disorders. The DGI should be used with caution in this population at this time, because of the lack of strong reliability.

Vestibular rehabilitation outcomes in patients with a history of migraine

Objectives The purpose of this study was to assess the efficacy of physical therapy for patients with vestibular disorders with and without a history of migraine headaches. Study Design Retrospective case series. Setting Outpatient physical therapy clinic. Patients Thirty patients with both a history of migraine and a diagnosis of vestibular/balance disorder considered unrelated to migraine were identified by retrospective chart review. Thirty patients without a history of migraine, matched retrospectively by diagnosis, vestibular function, and age (±5 years), were used as a comparison group. Interventions Both groups were treated with a custom-designed physical therapy program for a mean of 4.1 visits over a mean of 3.3 months. Main Outcome Measures Patients completed the Dizziness Handicap Inventory, the Activities-Specific Balance Confidence Scale, the Dynamic Gait Index, and the Timed Up & Go Test and rated the severity of their dizziness on an analog scale of 0 to 100. Results Significant differences were demonstrated within both groups between initial evaluation and discharge in each of the assessment measures used. Patients with a history of migraine demonstrated worse scores on all outcome measures than did the patients without a history of migraine. There were no statistically significant differences between the two groups scores before and after therapy except for the total Dizziness Handicap Inventory score at discharge (p < 0.05). Conclusions Patients with vestibular disorders with or without a history of migraine demonstrated improvements in both subjective and objective measures of balance after physical therapy. Patients with a history of migraine perceived a greater handicap from dizziness than did patients without a history of migraine that was greater than the difference in physical function performance measures between groups.

Vestibular function assessment using the NIH Toolbox

Objective: Development of an easy to administer, low-cost test of vestibular function. Methods: Members of the NIH Toolbox Sensory Domain Vestibular, Vision, and Motor subdomain teams collaborated to identify 2 tests: 1) Dynamic Visual Acuity (DVA), and 2) the Balance Accelerometry Measure (BAM). Extensive work was completed to identify and develop appropriate software and hardware. More than 300 subjects between the ages of 3 and 85 years, with and without vestibular dysfunction, were recruited and tested. Currently accepted gold standard measures of static visual acuity, vestibular function, dynamic visual acuity, and balance were performed to determine validity. Repeat testing was performed to examine reliability. Results: The DVA and BAM tests are affordable and appropriate for use for individuals 3 through 85 years of age. The DVA had fair to good reliability (0.41–0.94) and sensitivity and specificity (50%–73%), depending on age and optotype chosen. The BAM test was moderately correlated with center of pressure (r = 0.42–0.48) and dynamic posturography (r = −0.48), depending on age and test condition. Both tests differentiated those with and without vestibular impairment and the young from the old. Each test was reliable. Conclusion: The newly created DVA test provides a valid measure of visual acuity with the head still and moving quickly. The novel BAM is a valid measure of balance. Both tests are sensitive to age-related changes and are able to screen for impairment of the vestibular system.