Reliability, validity and minimal detectable change of the Mini-BESTest in Greek participants with chronic stroke.

OBJECTIVES: This study aimed to investigate the psychometric characteristics of reliability, validity and ability to detect change of a newly developed balance assessment tool, the Mini-BESTest, in Greek patients with stroke. DESIGN: A prospective, observational design study with test-retest measures was conducted. METHODS: A convenience sample of 21 Greek patients with chronic stroke (14 male, 7 female; age of 63 ± 16 years) was recruited. Two independent examiners administered the scale, for the inter-rater reliability, twice within 10 days for the test-retest reliability. Bland Altman Analysis for repeated measures assessed the absolute reliability and the Standard Error of Measurement (SEM) and the Minimum Detectable Change at 95% confidence interval (MDC95%) were established. The Greek Mini-BESTest (Mini-BESTestGR) was correlated with the Greek Berg Balance Scale (BBSGR) for assessing the concurrent validity and with the Timed Up and Go (TUG), the Functional Reach Test (FRT) and the Greek Falls Efficacy Scale-International (FES-IGR) for the convergent validity. RESULTS: The Mini-BESTestGR demonstrated excellent inter-rater reliability (ICC (95%CI) = 0.997 (0.995-0.999, SEM = 0.46) with the scores of two raters within the limits of agreement (meandif = -0.143 ± 0.727, p > 0.05) and test-retest reliability (ICC (95%CI) = 0.966 (0.926-0.988), SEM = 1.53). Additionally, the Mini-BESTestGRyielded very strong to moderate correlations with BBSGR(r = 0.924, p < 0.001), TUG (r = -0.823, p < 0.001), FES-IGR(r = -0.734, p < 0.001) and FRT (r = 0.689, p < 0.001). MDC95was 4.25 points. CONCLUSION: The exceptionally high reliability and the equally good validity of the Mini-BESTestGR, strongly support its utility in Greek people with chronic stroke. Its ability to identify clinically meaningful changes and falls risk need further investigation

The effect of transcranial direct current stimulation of the motor cortex on exercise-induced pain

Purpose: Transcranial direct current stimulation (tDCS) provides a new exciting means to investigate the role of the brain during exercise. However, this technique is not widely used in exercise science, with little known regarding effective electrode montages. This study investigated whether tDCS of the motor cortex (M1) would elicit an analgesic response to exercise-induced pain (EIP). Methods: Nine participants completed a VO2max test and three time to exhaustion (TTE) tasks on separate days following either 10 min 2 mA tDCS of the M1, a sham or a control. Additionally, seven participants completed 3 cold pressor tests (CPT) following the same experimental conditions (tDCS, SHAM, CON). Using a well-established tDCS protocol, tDCS was delivered by placing the anodal electrode above the left M1 with the cathodal electrode above dorsolateral right prefrontal cortex. Gas exchange, blood lactate, EIP and ratings of perceived exertion (RPE) were monitored during the TTE test. Perceived pain was recorded during the CPT. Results: During the TTE, no significant differences in time to exhaustion, RPE or EIP were found between conditions. However, during the CPT, perceived pain was significantly (P < 0.05) reduced in the tDCS condition (7.4 ± 1.2) compared with both the CON (8.6 ± 1.0) and SHAM (8.4 ± 1.3) conditions. Conclusion: These findings demonstrate that stimulation of the M1 using tDCS does not induce analgesia during exercise, suggesting that the processing of pain produced via classic measures of experimental pain (i.e., a CPT) is different to that of EIP. These results provide important methodological advancement in developing the use of tDCS in exercise