A study of the reliability and validity of the Six-Spot Step Test Cognitive in ambulatory persons with Parkinson's disease.

INTRODUCTION: Although dual-task walking deficits challenge ambulatory function in persons with Parkinson's disease (PwPD), ambulation measures that incorporate cognitive dual-task loads seem scarce. In its construct and instruction, the Six-Spot Step Test Cognitive (SSSTcog) ensures an equal focus on cognitive and motor tasks. The present study investigated the construct validity and test-retest reliability of the SSSTcog in PwPD. METHODS: Seventy-eight PwPD were recruited from outpatient clinics. The SSSTcog was completed twice within the same day and again three to seven days later. In addition, the cognitive Timed "Up and Go" test (TUGcog) and the Mini-BESTest were also conducted on the last day. Reliability and validity were estimated using Bland-Altman statistics, the minimal difference (MD), Intraclass Correlation Coefficient (ICC), and Spearman's rank correlation coefficient (ρ). RESULTS: The SSSTcog was found reliable (ICC: 0.84-0.89; MD: 23.7%-30.2%) and showed moderate construct validity to the TUGcog (ρ = 0.62, p < 0.001). Weak correlations to the Mini-BESTest (ρ = -0.33, p < 0.003) indicated low construct validity. Significantly (p < 0.001) higher dual-task costs were seen when performing the SSSTcog (77.6%) compared to the TUGcog (24.3%). CONCLUSIONS: In PwPD, the SSSTcog showed promising construct validity, acceptable to excellent reliability, making it a valid measure of functional mobility, including cognitive dual-tasking. Higher dual-task cost for the SSSTcog indicated actual cognitive-motor interference while performing the test.

A study of the discriminative properties of the Six-Spot Step Test in older adults at risk of falling and those not at risk.

OBJECTIVE: To investigate the discriminative properties of the Six-Spot Step Test in older adults with self-reported balance problems. METHODS: Seventy-five older adults aged ≥65 years completed the Six-Spot Step Test and the Timed "Up and Go" test. A Mini-BESTest score of ≤19 was used as a cutoff for defining the risk of falling, and a receiver operating characteristics curve was generated to determine relevant cutoff scores. RESULTS: An overall accuracy of 85% for the Six-Spot Step Test and 88% for the Timed "Up and Go" test were found. The probability of ruling out people at risk of falling increased with a test score shorter than 8.0 and 7.3 seconds on the Six-Spot Step Test and the Timed "Up and Go" test, respectively. Maximizing the total true positive and true negative test results generated a cutoff score of 8.8 seconds (accuracy 79%) and 8.3 seconds (accuracy 80%) for the Six-Spot Step Test and the Timed "Up and Go" test, respectively. CONCLUSIONS: The Six-Spot Step Test, which challenges the ability to adapt to more complex tasks during walking, discriminates accurately between older adults at risk of falling and those not at risk. Results as low as eight seconds qualify for fall-preventive interventions.

Unwrapping the "black box" of balance training in people with multiple sclerosis - A descriptive systematic review of intervention components, progression, and intensity.

BACKGROUND: Delineating the specific components of the existing balance training interventions in people with multiple sclerosis (PwMS) may contribute to a framework for future design and reporting of such interventions. Thus, we aimed to systematically synthesize how balance training frequency, intensity, time, type, duration, and progression are reported in balance training interventions for PwMS. METHODS: A systematic literature search was conducted in Medline, Embase, Web of Science, and Cinahl. Search terms were MS, postural balance, walking, gait, and randomized/quasi-randomized controlled or clinical trials. Articles including ambulatory PwMS and interventions designed to challenge the balance control system were eligible. Two investigators screened, selected, and extracted data independently. Data on study characteristics such as design, population, and balance training content were extracted. Categorization of balance training based on balance control components was performed. RESULTS: We included 40 studies grouped under five balance training categories. Balance interventions were well described regarding frequency, session time, and duration, but only two interventions described training intensity, and no systematic, gradual progression approach was reported for balance training adaptation over time. However, the balance training interventions included many sensory and motor components of the balance control system. Still, little focus was on reactive motor strategies, vestibular sense, and cognitive dual-tasking. CONCLUSIONS: Existing balance training interventions in PwMS primarily consist of practicing sensory and motor strategies. Future balance training interventions are encouraged to systematically monitor individual advancements in balance training adaptations and to apply the progressive overload principle (i.e. continuous increase in balance exercise stimulus over time). Furthermore, we suggest that balance training in PwMS is performed with high intensity near an individual's balance capacity limits. Finally, individualized balance training is recommended to cover all relevant components of balance control using the proposed framework.

Barriers toward Physical Activity in COPD: A Quantitative Cross-Sectional, Questionnaire-Based Study.

Chronic Obstructive Pulmonary Disease (COPD) is a progressive but preventable and treatable disease and the third leading cause of death globally. Even though it is evident that physical activity (PA) relieves dyspnea, anxiety, fatigue, and increases quality of life and functional capacity, it is seldom implemented in daily life in people with COPD. The aim of this study was to identify barriers toward PA in people with COPD and to examine the role of FEV1 and smoking status in PA. The study is a quantitative cross-sectional study conducted in Denmark among people with COPD. Data was collected using questionnaires developed by the authors after pilot testing. In total, 493 people with COPD were included. The most significant barrier toward PA was low motivation (p < 0,001 and p = 0,009) and comorbidity (p = 0,035 and p = 0,016). Fear of breathlessness was significantly (p < 0,001) correlated to low motivation. FEV1, and smoking status were not associated with the level of PA. In our study, the main reason why people with COPD did not engage in PA was low motivation, where fear of breathlessness and co-morbidity correlated significantly with low motivation. Studies have shown that doing activities that are enjoyable promotes PA in daily life, indicating that activities that enhance motivation might help people with COPD to see PA as part of their life rather than an obligation. Further exploratory studies are needed.

Examining the test-retest reliability and construct validity of the Six-Spot Step Test in older adults with self-reported balance problems.

OBJECTIVE: To evaluate the test-retest reliability and construct validity of the Six-Spot Step Test in older adults. DESIGN: Cross-sectional study. SETTING: Outpatient clinics. SUBJECTS: Sixty-six adults aged ⩾65 years with self-reported balance problems. MAIN MEASURE: The Six-Spot Step Test was completed twice on day 1. Three days later, the Six-Spot Step Test, the Timed "Up and Go" test, Dynamic Gait Index, the Mini-BESTest, and standing balance test were conducted. Reliability and validity were estimated using Bland-Altman statistics, minimal detectable change, Intraclass Correlation Coefficient (ICC), and Spearman's rank correlation coefficient (ρ). RESULTS: Participants had a mean (SD) age of 75.5 (6.6) years, a median (Q1-Q3) Montreal Cognitive Assessment test score of 26 (24-27), and a median (Q1-Q3) Falls Efficacy Scale International score of 22 (20-26). The study found within-day and between-day limits of agreements of ±15.7% and ±18.1%, respectively. The minimal detectable changes at the 95% level of confidence for within-day and between-day were 17.5% and 21.6%, and the ICCs were 0.96 (CI: 0.92-0.98) and 0.94 (CI: 0.86-0.97), respectively. A learning effect was observed between the first and second Six-Spot Step Test. Moderate to strong correlations were found between the Six-Spot Step Test and Mini-BESTest (ρ = -0.62), Dynamic Gait Index (ρ = -0.55), and the Timed "Up and Go" test (ρ = 0.79). Weak correlations were identified between the Six-Spot Step Test and static standing balance test (ρ < 0.38). CONCLUSION: The Six-Spot Step Test shows excellent relative consistency and moderate to high construct validity in older adults. A change of 21.6% is a true change in outcome.

Does disability level impact the relationship of muscle strength to walking performance in people with multiple sclerosis? a cross-sectional analysis.

BACKGROUND AND PURPOSE: Strength training can improve muscle weakness in people with multiple sclerosis (MS), but does not consistently improve walking. Disability level may impact the relationship of muscle weakness and walking performance in people with MS, but few studies have investigated the impact of disability on the relationship of strength and walking. The purpose of this study was to compare the relationships of strength in lower body and trunk muscles to walking performance between mild and moderate disability groups in people with MS. METHODS: Data from 36 participants with MS who had mild disability (Expanded Disability Status Scale - EDSS 0 to 3.5) and 36 participants who had moderate disability (EDSS 4.0 to 5.5) were analyzed. Hand-held dynamometry measured strength in eight muscle groups from the ankle, knee, hip, and trunk. Timed 25-Foot Walk (T25FW) and 6-Minute Walk Test (6MWT) measured walking speed and endurance, respectively. Pearson correlations and beta coefficients (ß) were reported for each bivariate relationship of muscle strength to T25FW and 6MWT from both mild and moderate disability groups. Linear regression was then used to compare differences in beta coefficients (Δß) between disability groups for the relationship of each muscle variable to T25FW and 6MWT. A positive Δß indicated a stronger relationship of strength to walking performance in the mild disability group, while a negative Δß favored the moderate disability group. RESULTS: Overall, there were stronger Pearson correlations between muscle strength variables to T25FW and 6MWT in the mild (r = 0.57 to 0.77) compared to moderate disability group (r = 0.10 to 0.54). The mild disability group had significantly greater beta coefficients for T25FW with ankle dorsiflexion (Δß = 0.67, 95%CI: 0.27-1.07), knee extension (Δß = 0.68, 95%CI: 0.28-1.08), and hip abduction (Δß = 0.77, 95%CI: 0.01-1.52); and for 6MWT with knee extension (Δß = 0.47, 95%CI: 0.06 to 0.88). DISCUSSION AND CONCLUSION: For people with MS, muscle strength in the lower extremity and trunk may be a more important contributor to T25FW in mild versus moderate disability, but not for 6MWT. While more studies are needed, these results may help to inform rehabilitation intervention when prioritizing strength training to improve walking.

How do resistance training and balance and motor control training affect gait performance and fatigue impact in people with multiple sclerosis? A randomized controlled multi-center study.

BACKGROUND: Despite a shared purpose of improving functional capacity, the principles of progressive resistance training (PRT) and balance and motor control training (BMCT) are fundamentally different. OBJECTIVES: To investigate the effects of PRT and BMCT on gait performance and fatigue impact in people with multiple sclerosis (PwMS). METHODS: A multi-center, single-blinded, cluster-randomized controlled trial with two intervention groups (PRT and BMCT) and a control group (CON). The interventions lasted 10 weeks. A total of 71 participants with impaired mobility (Timed 25-Foot Walk (T25FW) > 5 seconds or Six Spot Step Test (SSST) > 8 seconds) were enrolled. Primary outcomes were the T25FW and the SSST. Fatigue impact, self-perceived gait function, 6-minute walk, balance, and muscle strength were secondary outcomes. RESULTS: In total, 83% completed the study. The primary comparisons showed that BMCT, but not PRT, improved T25FW, SSST, and self-perceived gait function when compared to CON. Secondary comparisons showed that BMCT improved SSST more than PRT, while T25FW did not differ. Both BMCT and PRT reduced the fatigue impact. Finally, the effect of BMCT was superior to PRT on dynamic balance, while PRT was superior to BMCT on knee extensor muscle strength. CONCLUSION: BMCT, but not PRT, was superior to CON in improving gait performance, while both BMCT and PRT reduced fatigue.

A study of the discriminative properties of the Six-Spot Step Test in people with Parkinson's disease at risk of falling.

BACKGROUND: Clinical tests that can discriminate between people at risk of falling and those not at risk are warranted. The discriminative properties of the Six-Spot Step Test was investigated in people with Parkinson's disease at risk of falling. METHODS: Eighty-one participants with a median age of 69 years (Q1-Q3:63-74) and a median Hoehn and Yahr score of 2.5 (Q1-Q3:2-3) completed the Six-Spot Step Test and the Timed "Up and Go" test. A mini-BESTest score of 19 or below was used as a cut-off for defining risk of falling, and a receiver operating characteristics curve was generated to determine clinical relevant cut-off scores. RESULTS: A cut-off score of 7.0 and 6.8 seconds identified people not at risk of falling, while 11.1 and 9.4 seconds identified people at risk of falling for the Six-Spot Step Test and the Timed "Up and Go" test, respectively. When maximizing the sensitivity and specificity a cut-off score of 9.2 (accuracy of 84%) and 8.1 seconds (accuracy of 70%) was found for the Six-Spot Step Test and the Timed "Up and Go" test, respectively. CONCLUSION: The Six-Spot Step Test discriminates accurately between people with Parkinson's disease at risk of falling and people not at risk.

A study of the validity of the Six-Spot Step Test in ambulatory people with Parkinson's disease.

OBJECTIVE: The aim of this study was to evaluate the concurrent and divergent validity of the Six-Spot Step Test in mild to moderately impaired people with Parkinson's disease. DESIGN: Cross-sectional cohort study. SETTING: Outpatient clinics. SUBJECTS: Fifty-eight people with Parkinson's disease. MAIN MEASURE: The Six-Spot Step Test, the Timed "Up and Go" test, the mini-Balance Evaluation Systems Test (mini-BESTest), and postural sway were tested on the same day, and the Spearman's Rank Correlation Coefficient (ρ) was used for data analysis. RESULTS: Subjects had a median age of 68 years (Q1-Q3: 62-73), a median Hoehn and Yahr score of 2.5 (Q1-Q3: 2-3), a median Six-Spot Step Test score of 7.9 seconds (Q1-Q3: 6.5-9.2), a median Timed "Up and Go" test score of 7.0 seconds (Q1-Q3: 5.6-7.9), a median mini-BESTest score of 22.5 (Q1-Q3: 19.8-25.0), and a median postural sway score of 27.9 mm2 (Q1-Q3: 15.0-53.5) and 22.5 mm/s (Q1-Q3: 14.6-39.8). Statistical significant correlations were found between the Six-Spot Step Test and the Timed "Up and Go" test (ρ = 0.81) and the mini-BESTest (ρ = -0.64), whereas no significant relations were identified between the Six-Spot Step Test and postural sway (ρ = 0.18, P > 0.05). CONCLUSION: In patients with Parkinson's disease, the Six-Spot Step Test showed promising concurrent validity to other recommended clinical tests for encompassing balance capacity and capacity of functional mobility, making it a reasonable and easily administered alternative to existing assessment tools when measuring walking agility. As expected, weak correlates to postural sway revealed that the Six-Spot Step test is not a valid measure of standing balance.

How much does balance and muscle strength impact walking in persons with multiple sclerosis? - A cross-sectional study.

INTRODUCTION: Despite the multitude of rehabilitation interventions targeting gait impairments in persons with multiple sclerosis (PwMS), only little is known about the relative association of muscle strength and balance on different gait outcomes. AIM: To determine the relative association of balance and muscle strength to three gait performance outcomes in PwMS. METHOD: 90 PwMS were enrolled in this cross-sectional study (72% women; mean age=49.8 ±â€¯10.5 years; mean EDSS=3.7 ±â€¯1.3. Spearman correlation and multivariate linear regression analysis were used to determine associations between three (dependent) gait outcomes (six-minute walk test (6MW), Timed 25-Foot Walk (T25FW), and Six Spot Step Test (SSST)). Explanatory variables were maximal muscle strength of the knee extensors, kneeflexors, plantarflexors and dorsiflexors, static balance (postural sway), functional balance (Mini-BESTest) and age and gender. RESULTS: Static balance (r = 0.30 to 0.53; p<.05) and muscle strength of the knee extensors, knee flexors, plantarflexors and dorsiflexors (r = 0.28 to 0.47; p<.05) were weakly related to all gait performance outcomes, while functional balance showed strong relationships (r = 0.70 to 0.83; p<.05). Multivariate regression models including postural sway, muscle strength, and age and gender accounted for 32-39% of the variability in the 6MW, T25FW, and SSST. In 6MW and T25FW, with standardized beta coefficients for postural sway and muscle strength ranging from -0.34 to -0.37 (SE=0.09) and 0.18 to 0.35 (SE=0.10 to 0.12), respectively. For SSST, significant associations were only observed for balance. CONCLUSIONS: Balance and muscle strength are significantly associated with gait performance during fast walking, whereas only balance was associated with more complex walking tasks.

Test-retest reliability and limits of agreement of the Six-Spot Step Test in people with Parkinson's disease.

OBJECTIVE:: The aim of this study was to evaluate the within-day and day-to-day agreement and reliability of the Six-Spot Step Test in mild to moderately disabled people with Parkinson's disease. DESIGN:: Cross-sectional cohort study. SETTING:: Outpatient clinics. SUBJECTS:: Forty-four people with Parkinson's disease. MAIN MEASURE:: The Six-Spot Step Test was completed twice on day 1. Two days later, the Six-Spot Step Test was completed again. The agreement was estimated by Bland-Altman statistics with 95% limits of agreement, and reliability was estimated by the intraclass correlation coefficient. RESULTS:: Subjects had a mean (SD) age of 67.8 (6.8) years, a median (range) Hoehn and Yahr score of 2.5 (1-4) and a mean (SD) Six-Spot Step Test score of 8.1 (1.8), 7.6 (1.7) and 7.6 (1.6) seconds on test occasions 1 to 3. An agreement for within-day and day-to-day of ±1.8 (±23.7%) and ±2.2 (±26.7%) seconds was found, respectively. The reliability was 0.81 and 0.76 within-day and day-to-day, respectively. A small learning effect was observed ( P < 0.05) between the first and second Six-Spot Step Test, but there was no learning between the second and third occasions. CONCLUSION:: The Six-Spot Step Test has an acceptable within-day and day-to-day agreement and reliability in mild to moderately disabled people with Parkinson's disease. A change of 2.2 seconds can be regarded as a true change. To minimize learning effects, test trials of the Six-Spot Step Test are recommended before use.

Test-retest agreement and reliability of the Six Spot Step Test in persons with multiple sclerosis.

BACKGROUND: The Six Spot Step Test (SSST) extends traditional walking outcomes in persons with multiple sclerosis (PwMS) by further challenging components of coordination and balance. Nonetheless, the test-retest agreement of the SSST has not been investigated. OBJECTIVE: To determine the within-day, day-to-day, and inter-rater agreement and reliability of the SSST in PwMS. A secondary aim was to investigate the validity of handheld timing. METHODS: A total of 38 PwMS with an Expanded Disability Status Scale (EDSS) <6.5 completed two SSSTs with a 5-minute break in-between. After 2 days, this procedure was repeated. Bland-Altman analysis was performed to determine the 95% Limits of Agreement (LOA) and Intraclass Correlation Coefficient (ICC) was calculated. In a subgroup of 18 PwMS, the SSSTs were video-recorded and timed by a second investigator. RESULTS: The relative LOA within and between days were ±15% and ±19%, while ICC were 0.987 and 0.983, respectively. A minor learning effect was found over four tests. The handheld timing error was ±0.5 seconds when compared to video-based timing. CONCLUSION: The SSST has an acceptable within- and between-day agreement and reliability. For interventional purposes, a change of >19% can be regarded as a real change. Valid timing can be performed by a handheld stopwatch.

How does strength training and balance training affect gait and fatigue in patients with Multiple Sclerosis? A study protocol of a randomized controlled trial.

INTRODUCTION: Multiple sclerosis (MS) is characterized by a demyelination that results in reduced conductivity in the somatosensory nervous system, decreased muscle strength, vestibular alteration, and severe fatigue. Progressive resistance training (PRT) has proven to be a promising intervention showing a positive effect on muscle strength. Another promising intervention frequently used in neuro-rehabilitation is task specific training where also Balance and Motor Control Training (BMCT) are incorporated. Interestingly, the principles of BMCT do fundamentally contrast the principles of PRT in terms of variation in movement pattern, loading and repetitions. Consequently, knowledge of any diverse effect would be of clinical relevance. AIM: To evaluate the effects of PRT and BMCT on gait, balance and fatigue in persons with MS. METHOD: A three-armed multi-center, single-blinded cluster randomized controlled trial with two intervention groups (1. PRT of the lower extremities. 2. BMCT that challenges gait function) and a control group that receives usual care while on a waitlist for a combined PRT + BMCT intervention performed after the two interventions groups have completed their interventions. The interventions last ten weeks with two sessions per week, in groups of 3-6 participants. Number of participants is 30 per intervention - 90 in total. Primary outcome measures for gait function are the Timed 25 Foot Walk (T25FW) and the Six Spot Step Test (SSST). Secondary outcomes are fatigue, perceived gait function, temporo-spatial gait characteristics, balance and strength.Inclusion criteria are: EDSS 2-6, SSST >8 sec and T25FW >5 sec. Exclusion: Recent attacks and ongoing intensive rehabilitation. ANALYSIS: The effects in the three groups are examined in a mixed effects regression analysis with group and time as fixed effects and center and patient within center as random effects. Spearman or Pearson correlation analysis will be conducted on baseline data to determine associations between the primary outcomes on gait function and the secondary outcomes on fatigue, spatial gait parameters, balance and patient reported measures. TRIAL REGISTRATION: The study is approved by the Regional ethical committee and registered at clinicaltrials.gov, NCT02870023.

Reproducibility of tender point examination in chronic low back pain patients as measured by intrarater and inter-rater reliability and agreement: a validation study.

OBJECTIVES: To evaluate the reliability and agreement of digital tender point (TP) examination in chronic low back pain (LBP) patients. DESIGN: Cross-sectional study. SETTINGS: Hospital-based validation study. PARTICIPANTS: Among sick-listed LBP patients referred from general practitioners for low back examination and return-to-work intervention, 43 and 39 patients, respectively (18 women, 46%) entered and completed the study. MAIN OUTCOME MEASURES: The reliability was estimated by the intraclass correlation coefficient (ICC), and agreement was calculated for up to ±3 TPs. Furthermore, the smallest detectable difference was calculated. RESULTS: TP examination was performed twice by two consultants in rheumatology and rehabilitation at 20 min intervals and repeated 1 week later. Intrarater reliability in the more and less experienced rater was ICC 0.84 (95% CI 0.69 to 0.98) and 0.72 (95% CI 0.49 to 0.95), respectively. The figures for inter-rater reliability were intermediate between these figures. In more than 70% of the cases, the raters agreed within ±3 TPs in both men and women and between test days. The smallest detectable difference between raters was 5, and for the more and less experienced rater it was 4 and 6 TPs, respectively. CONCLUSIONS: The reliability of digital TP examination ranged from acceptable to excellent, and agreement was good in both men and women. The smallest detectable differences varied from 4 to 6 TPs. Thus, TP examination in our hands was a reliable but not precise instrument. Digital TP examination may be useful in daily clinical practice, but regular use and training sessions are required to secure quality of testing.