Pay attention: you can fall! The Mini-BESTest scale and the turning duration of the TUG test provide valid balance measures in neurological patients: a prospective study with falls as the balance criterion.

Background: Balance, i.e., the ability not to fall, is often poor in neurological patients and this impairment increases their risk of falling. The Mini-Balance Evaluation System Test (Mini-BESTest), a rating scale, the Timed Up and Go (TUG) test, and gait measures are commonly used to quantify balance. This study assesses the criterion validity of these measures as balance measures. Methods: The probability of being a faller within nine months was used as the balance criterion. The Mini-BESTest, TUG (instrumented with inertial sensors), and walking test were administered before and after inpatient rehabilitation. Multiple and LASSO logistic regressions were used for the analysis. The diagnostic accuracy of the model was assessed with the area under the curve (AUC) of the receiver operating characteristic curve. Mobility measure validity was compared with the Akaike Information Criterion (AIC). Results: Two hundred and fourteen neurological patients (stroke, peripheral neuropathy, or parkinsonism) were recruited. In total, 82 patients fell at least once in the nine-month follow-up. The Mini-BESTest (AUC = 0.69; 95%CI: 0.62-0.76), the duration of the TUG turning phase (AUC = 0.69; 0.62-0.76), and other TUG measures were significant faller predictors in regression models. However, only the turning duration (AIC = 274.0) and Mini-BESTest (AIC = 276.1) substantially improved the prediction of a baseline model, which only included fall risk factors from the medical history (AIC = 281.7). The LASSO procedure selected gender, disease chronicity, urinary incontinence, the Mini-BESTest, and turning duration as optimal faller predictors. Conclusion: The TUG turning duration and the Mini-BESTest predict the chance of being a faller. Their criterion validity as balance measures in neurological patients is substantial.

Differential Item Functioning of the Mini-BESTest Balance Measure: A Rasch Analysis Study.

The Mini-Balance Evaluation Systems Test (Mini-BESTest), a 14-item scale, has high content validity for balance assessment. This study further examines the construct validity of the Mini-BESTest with an emphasis on its measurement invariance. The Mini-BESTest was administered to 292 neurological patients in two sessions (before and after rehabilitation) and evaluated with the Rasch analysis (Many-Facet Rating Scale Model: persons, items, sessions). Categories' order and fit to the model were assessed. Next, maps, dimensionality, and differential item functioning (DIF) were examined for construct validity evaluation. DIF was inspected for several clinically important variables, including session, diagnosis, and assistive devices. Mini-BESTest items had ordered categories and fitted the Rasch model. The item map did not flag severe construct underrepresentation. The dimensionality analysis showed that another variable extraneous to balance affected the score of a few items. However, this multidimensionality had only a modest impact on measures. Session did not cause DIF. DIF for assistive devices affected six items and caused a severe measurement artefact. The measurement artefact caused by DIF for diagnosis was negligible. The Mini-BESTest returns interval measures with robust construct validity and measurement invariance. However, caution should be used when comparing Mini-BESTest measures obtained with and without assistive devices.

The Falls Efficacy Scale International is a valid measure to assess the concern about falling and its changes induced by treatments.

OBJECTIVE: To test with the Rasch analysis the psychometric properties of the Falls Efficacy Scale International, a questionnaire for measuring concern about falling. DESIGN: Longitudinal observational study, before-after rehabilitation. SETTING: Inpatient rehabilitation. SUBJECTS: A total of 251 neurological patients with balance impairment. INTERVENTIONS: Physiotherapy and occupational therapy aimed at reducing the risk of falling. MAIN MEASURES: Participants (median age, first-third quartile: 74.0, 65.5-80.5 years; stroke and polyneuropathy: 43% and 21% of the sample, respectively) received a balance assessment (Falls Efficacy Scale International included) pre- and post-rehabilitation. Rasch analysis was used to evaluate the Falls Efficacy Scale International. Differential item functioning, which assesses the measures' stability in different conditions (e.g. before vs. after treatment) and in different groups of individuals, was tested for several variables. RESULTS: Patients suffered a moderate balance impairment (Mini-BESTest median score; first-third quartile: 15; 11-19), mild-moderate concern about falling (Falls Efficacy Scale International: 28; 21-37) and motor disability (Functional Independence Measure, motor domain: 70.0; 57.0-76.5). Falls Efficacy Scale International items fitted the Rasch model (range of infit and outfit mean square statistics: 0.8-1.32 and 0.71-1.45, respectively) and the questionnaire's reliability was satisfactory (0.87). No differential item functioning was found for treatment, gender, age and balance impairment. Differential item functioning was found for diagnosis and disability severity, but it is shown that it is not such as to bias measures. CONCLUSIONS: Falls Efficacy Scale International ordinal scores can be turned into interval measures, i.e. measures of the type of temperature. Being differential item functioning-free for treatment, these measures can be safely used to compare concern about falling before and after rehabilitation, such as when interested in assessing the rehabilitation effectiveness.

Turning and sit-to-walk measures from the instrumented Timed Up and Go test return valid and responsive measures of dynamic balance in Parkinson's disease.

BACKGROUND: Balance impairment is a hallmark of Parkinson's disease with dramatic effects for patients (e.g. falls). Its assessment is thus of paramount importance. The aim of this work is to assess which measures from the instrumented Timed Up and Go test (recorded with inertial sensors) are valid balance measures in Parkinson's disease and evaluate their responsiveness to rehabilitation. METHODS: The Mini-BESTest (a criterion-standard balance measure) and the instrumented Timed Up and Go test (with inertial sensors secured to the trunk) were administered to 20 Parkinson's disease patients before and after inpatient rehabilitation (median [IQR]; 76.5 [8.25] years; 5 females; Hoehn and Yahr stage: 2.5 [0.5]). 81 parameters from the instrumented Timed Up and Go test were evaluated. Multiple factor analysis (a variant of principal component analysis for repeated measurements) and effect sizes were used to assess validity and responsiveness, respectively. FINDINGS: Only the first component of the multiple factor analysis correlated with the Mini-BESTest, and 21 measures from the instrumented Timed Up and Go test had large loadings on this component. However, only three of these 21 measures also directly correlated with the Mini-BESTest (trunk angular velocities from sit-to-walk and turning; r = 0.46 to 0.50, P = 0.021 to 0.038). Sit-to-walk angular velocity showed greater responsiveness than the Mini-BESTest, while turning showed slightly less. INTERPRETATION: Angular velocities from the turning and sit-to-walk phases of the Timed Up and Go test are valid balance measures in Parkinson's disease and are also responsive to rehabilitation.

Responsiveness to rehabilitation of balance and gait impairment in elderly with peripheral neuropathy.

Elderly people with peripheral neuropathy of the lower limbs (PNLL) demonstrate a typical balance and gait impairment because of sensory ataxia. There is evidence that rehabilitation produces important gains on balance and gait. However, responsiveness to rehabilitation of balance and gait measures is unknown in PNLL. Aim of the current work is to evaluate the responsiveness to rehabilitation of balance, gait and sensory ataxia measures in elderly with PNLL. Twenty-five elderly with PNLL attending physiotherapy and occupational therapy during inpatient rehabilitation were recruited. Balance and gait measures (including static posturography, TUG test and the 10 m walking test) were administered on admission and discharge. An accelerometer secured to the trunk was used for TUG recording and static balance assessment. Static balance was tested with open and closed eyes, so as to assess sensory ataxia. Following rehabilitation, patients improved gait [admission vs discharge, mean(SD): 0.86(0.33) vs 0.98(0.32) m/s], TUG [18.7(7.8) vs 15.1(5.2) s] and turning [46.2(15.3) vs 53.3(15.3) °/s]. However, none of 12 static balance parameters derived from trunk acceleration significantly changed. Principal component analysis showed that before training, eyes closed and eyes open balance correlated with orthogonal components (one and two vs. three and four). After training, eyes open and eyes closed balance were more similar to each other being both correlated with component one. Responsiveness to rehabilitation is larger for gait than static balance measured by trunk acceleration. However, exercise can also have a beneficial effect on sensory ataxia by making eyes closed balance more similar to eyes open balance.

How do patients improve their timed up and go test? Responsiveness to rehabilitation of the TUG test in elderly neurological patients.

BACKGROUND: The timed up and go (TUG) test is widely used for assessing treatments effectiveness on elderly mobility. Although the TUG test consists of different tasks (e.g. walking and turning), the total TUG duration (TTD) is usually the only outcome measure, with TTD shortening indicating the patient's improvement. RESEARCH QUESTION: Does TTD shortening reflect the improvement of each TUG tasks or does it reflect the improvement of only some of them? METHODS: This retrospective study recruited 120 elderly patients (mean, SD: 76.9, 6.6 years) admitted to inpatient rehabilitation because of an acute or chronic neurological disease (acute patients, AP; chronic patients, CP). TTD and TUG tasks duration was measured on admission and discharge (five trials/session) by means of the instrumental TUG test (ITUG). Likelihood ratios (LRs) were used for inferring TUG tasks improvement from TTD improvement. TTD and TUG tasks have improved if at least four measurements on discharge were shorter than the shortest measurement on admission. RESULTS: TTD improvement per se is not enough to claim that all the TUG tasks have improved (LR+AP = 1.32; LR+CP = 1.85). Conversely, if TTD has not improved, not even a single TUG task has improved (LR-AP = 0.13; LR-CP = 0.19). If TTD has improved, there is at least one TUG task that actually improved (LR+AP = 3.17; LR+CP = 9.54). The improvement of all TUG tasks can be only inferred in the (unusual) event of a large TTD shortening (AP: >39%, LR+AP = 6.26; CP: >30%, LR+CP = 9.0). SIGNIFICANCE: In most cases, TTD improvement is not associated with the improvement of all TUG tasks. Moreover, when TTD has improved there is at least a TUG task that has improved, but that remains unknown. To actually understand how treatments ameliorate patients' mobility, ITUG with TUG task duration measurement should be preferred to TTD.

No evidence of effectiveness of mirror therapy early after stroke: an assessor-blinded randomized controlled trial.

OBJECTIVE: The aim of this study was to investigate the efficacy of mirror therapy on upper-limb recovery in early post-stroke patients. DESIGN: Assessor-blinded randomized controlled trial. SETTING: Inpatient rehabilitation clinic. SUBJECTS: A total of 40 patients with upper-limb impairment due to a first-ever ischaemic or haemorrhagic stroke, within four weeks from the cerebrovascular accident. INTERVENTION: The intervention group received mirror therapy, while the control group received sham therapy. During mirror therapy, patients' sound hand was reflected by a mirror. During sham therapy, an opaque surface replaced the mirror-reflecting surface. Both the mirror therapy and sham therapy groups practised their sound hand with exercises, ranging from the simple elbow flexion-extension to complex tasks (e.g. reaching and grasping). Mirror therapy and sham therapy were added to conventional rehabilitation. MAIN MEASURES: Primary outcome includes Fugl-Meyer upper extremity scale. Secondary outcomes include action research arm test (ARAT) and functional independence measure (FIM) scale. Outcomes were measured at the beginning (T0) and end (T1) of the treatment. RESULTS: At baseline, both groups (sham therapy vs. mirror therapy; mean (SD)) were comparable for Fugl-Meyer (30.9 (23.9) vs. 28.5 (21.8)), ARAT (25.1 (25.5) vs. 23.5 (24)) and FIM (71.0 (20.6) vs. 72.9 (17.8)) scores. At the end of the treatment, both groups significantly improved in the Fugl-Meyer (40.6 (21.3) vs. 38.3 (23.4)), ARAT (31.9 (23.0) vs. 30 (24.1)) and FIM (100.3 (21.9) vs. 99.4 (22.6)) scores. However, at T1, no significant difference was observed between the sham therapy and mirror therapy groups, neither for the Fugl-Meyer, nor for ARAT and FIM scores. CONCLUSION: Compared with sham therapy, mirror therapy did not add additional benefit to upper-limb recovery early after stroke.

Criterion validity of the instrumented Timed Up and Go test: A partial least square regression study.

The Timed Up and Go (TUG) test is a common mobility measure in rehabilitation. With the instrumental TUG test (ITUG; i.e. the TUG measured by inertial measurement units, IMUs), several movement measures are newly available. However, the clinical meaning of these new measures is not totally clear. Aim of the current work is to evaluate the validity of different ITUG parameters as a measure of balance. Neurological patients (n = 122; 52 females; 89 older than 65 years) completed the TUG test with IMUs secured to their back. IMUs signals were used to split the TUG test in five phases (sit-to-stand, walk1, turn1, walk2 and turn-and-sit) and twelve movement parameters were obtained. Experienced clinicians administered the Mini-BESTest (MB) scale, a sound balance measure. The partial least square regression (PLSR) was used to explore the association between the ITUG variables and the MB measure. A PLSR model with twelve ITUG variables had satisfactory fit parameters (RMSEP: 11%; R2: 0.41, 95% CI: 0.28-0.54; regression line: 1, 95% CI: 0.78-1.22). Three ITUG variables (i.e. turn1 vertical angular velocity, turn1 duration and turn2 vertical angular velocity) were found to be the most important predictors of the MB measure. A PLSR model with the turning variables only had fit parameters comparable to that of the twelve variables model. Turning parameters from the TUG test are good predictors of the MB scale. The mean angular velocity during turning and the duration of the turning phase are thus proposed as a valid, ratio-level measures of balance in neurological patients.