Physical and psychological aspects of multiple sclerosis: Revisiting the Multiple Sclerosis Impact Scale (MSIS-29).

BACKGROUND: The MSIS-29 measures the physical and psychological impact of MS. OBJECTIVE: The associations between MSIS-29 domains and demographic/clinical aspects were examined and trajectories analysed over time. METHODS: Data were collected in the Trajectories of Outcome in Neurological Conditions study for a diverse population of people with MS, with follow-up for up to 5 years. Following Rasch analysis, minimal important change (MIC) was computed for ensuing total, physical and psychological domains. RESULTS: Fit to the Rasch model using data from 5921 participants validated physical, psychological and total domains, and the conversion table transforms raw scores to interval-level metric equivalents. These domains showed significant differences across demographic (age, gender, employment, education, and marital status) and clinical (subtype, treatment, and duration) factors with large effect sizes. The MIC scores were physical: 9.1, total: 14.1, which were both above measurement error, and psychological: 5.5 which was not, so 1.6% of participants reported psychological change which was clinically important but not statistically significant. Trajectory analysis showed three groups, one stable and two with significant slopes, improving and deteriorating. CONCLUSION: The MSIS-29 has shown adequate fit to the Rasch model after accommodating problems with local item dependency, through a bi-factor solution. The domains showed good discrimination across key factors.

Determining minimal clinically important differences in the Hammersmith Functional Motor Scale Expanded for untreated spinal muscular atrophy patients: An international study.

BACKGROUND AND PURPOSE: Spinal muscular atrophy (SMA) is a rare and progressive neuromuscular disorder with varying severity levels. The aim of the study was to calculate minimal clinically important difference (MCID), minimal detectable change (MDC), and values for the Hammersmith Functional Motor Scale Expanded (HFMSE) in an untreated international SMA cohort. METHODS: The study employed two distinct methods. MDC was calculated using distribution-based approaches to consider standard error of measurement and effect size change in a population of 321 patients (176 SMA II and 145 SMA III), allowing for stratification based on age and function. MCID was assessed using anchor-based methods (receiver operating characteristic [ROC] curve analysis and standard error) on 76 patients (52 SMA II and 24 SMA III) for whom the 12-month HFMSE could be anchored to a caregiver-reported clinical perception questionnaire. RESULTS: With both approaches, SMA type II and type III patients had different profiles. The MCID, using ROC analysis, identified optimal cutoff points of -2 for type II and -4 for type III patients, whereas using the standard error we found the optimal cutoff points to be 1.5 for improvement and -3.2 for deterioration. Furthermore, distribution-based methods uncovered varying values across age and functional status subgroups within each SMA type. CONCLUSIONS: These results emphasize that the interpretation of a single MCID or MDC value obtained in large cohorts with different functional status needs to be made with caution, especially when these may be used to assess possible responses to new therapies.

Minimal Clinically Important Differences in Hand Pain Intensity (Numerical Pain Rate Scale) and Related-Function (Boston Carpal Tunnel Questionnaire) in Women With Carpal Tunnel Syndrome.

OBJECTIVE: To calculate the minimal clinically important differences (MCIDs) for hand pain intensity and the Boston Carpal Tunnel Questionnaire (BCTQ) in a sample of women with carpal tunnel syndrome (CTS). DESIGN: Secondary analysis of a randomized controlled trial. SETTING: A Hospital Rehabilitation Unit. PARTICIPANTS: One hundred twenty women with clinical and electromyographic diagnosis of CTS who were randomly assigned into 2 groups (N=120). INTERVENTIONS: One group received 3 sessions of manual physical therapy (n=60) and the other group received surgery (n=60). MAIN OUTCOME MEASURES: Mean and the worst pain intensity (numerical pain rate scale, 0-10 points) and functional status and symptoms' severity subscales of the BCTQ questionnaire were assessed before and 1 month after treatment. The Global Rating of Change (GROC) was used as the anchor variable for determining the MCID. RESULTS: A change of 1.5 and 2.5 points in mean and the worst pain intensity represents the MCID for Numerical Pain Rating Scale, whereas a change of 0.23 and 0.64 points in functional status and symptoms' severity represents the MCID for each subscale of the BCTQ. All variables showed acceptable discrimination between patients classified as "improved" and those classified as "stable/not improved" (area under the curve≥0.72). Mean pain intensity (Youden index, 0.53; sensitivity: 73.3%; specificity: 80%) and symptoms' severity (Youden index, 0.69; sensitivity: 90%; specificity: 77.8%) showed the best discriminative ability expressed as a percentage of prediction. Participants classified as "improved" had significantly greater improvements in pain intensity, functional status, and symptoms' severity compared with those classified as "stable/not improved". CONCLUSION: A change of 1.5 and 2.5 points in mean and the worst pain and a change of 0.23 and 0.64 points in functional status and symptoms' severity represents the MCID for pain intensity and BCTQ in women with CTS 1 month after treatment.

Measuring Ultrasonographic Thickness of the Achilles Tendon Insertion Is Less Reliable Than the Midportion in Healthy Tendons and Patients With Tendinopathy.

INTRODUCTION: Ultrasound is the preferred imaging method in the diagnostic process of Achilles tendinopathy (AT). Ultrasound tissue characterization (UTC) is a frequently used, standardized and valid method to assess tendon geometry in AT patients. It is unknown whether UTC is reliable for measuring Achilles tendon thickness. The aim of the study was to assess intra- and inter-rater reliability of Achilles tendon thickness measurements using UTC in both asymptomatic individuals and patients with AT, and to evaluate if the reliability of thickness measurements differs between the midportion and insertional area. METHODS: Exactly 50 patients with AT and 50 asymptomatic individuals were included. Using the conventional US and standardized UTC procedure maximum thickness was measured in the midportion and insertion region. To determine inter- and intra-rater reliabilities, the intraclass correlation coefficient (ICC) was used. RESULTS: The ICC values for inter- and intra-rater reliability were classified as "excellent," for the AT group (0.93 [95% CI: 0.88-0.96] and 0.95 [0.92-0.97]) and asymptomatic participants (0.91 [0.87-0.94] and 0.94 [0.92-0.96]). The reliability of measuring tendon thickness in the midportion region was "excellent," with both inter-rater (0.97 [0.95-0.98]) and intra-rater (0.98 [0.96-0.99]) ICC values indicating high levels of agreement. In the insertional region, ICC values for inter-rater (0.79 [0.69-0.87]) and intra-rater (0.89 [0.84-0.93]) reliability were "moderate to good." CONCLUSION: We showed excellent reliability for measuring the US thickness of the midportion and good reliability of measuring the insertional region in patients with AT. Significantly lower ICCs were observed for the reliability of thickness measurements in the insertional region when compared with the midportion.

Minimal detectable change of gait and balance measures in older neurological patients: estimating the standard error of the measurement from before-after rehabilitation data thanks to the linear mixed-effects models.

BACKGROUND: Tracking gait and balance impairment in time is paramount in the care of older neurological patients. The Minimal Detectable Change (MDC), built upon the Standard Error of the Measurement (SEM), is the smallest modification of a measure exceeding the measurement error. Here, a novel method based on linear mixed-effects models (LMMs) is applied to estimate the standard error of the measurement from data collected before and after rehabilitation and calculate the MDC of gait and balance measures. METHODS: One hundred nine older adults with a gait impairment due to neurological disease (66 stroke patients) completed two assessment sessions before and after inpatient rehabilitation. In each session, two trials of the 10-meter walking test and the Timed Up and Go (TUG) test, instrumented with inertial sensors, have been collected. The 95% MDC was calculated for the gait speed, TUG test duration (TTD) and other measures from the TUG test, including the angular velocity peak (ωpeak) in the TUG test's turning phase. Random intercepts and slopes LMMs with sessions as fixed effects were used to estimate SEM. LMMs assumptions (residuals normality and homoscedasticity) were checked, and the predictor variable ln-transformed if needed. RESULTS: The MDC of gait speed was 0.13 m/s. The TTD MDC, ln-transformed and then expressed as a percentage of the baseline value to meet LMMs' assumptions, was 15%, i.e. TTD should be < 85% of the baseline value to conclude the patient's improvement. ωpeak MDC, also ln-transformed and expressed as the baseline percentage change, was 25%. CONCLUSIONS: LMMs allowed calculating the MDC of gait and balance measures even if the test-retest steady-state assumption did not hold. The MDC of gait speed, TTD and ωpeak from the TUG test with an inertial sensor have been provided. These indices allow monitoring of the gait and balance impairment, which is central for patients with an increased falling risk, such as neurological old persons. TRIAL REGISTRATION: NA.

BackMov: Individualized Motion Capture-Based Test to Assess Low Back Pain Mobility Recovery after Treatment.

Low back pain (LBP) is a common issue that negatively affects a person's quality of life and imposes substantial healthcare expenses. In this study, we introduce the (Back-pain Movement) BackMov test, using inertial motion capture (MoCap) to assess lumbar movement changes in LBP patients. The test includes flexion-extension, rotation, and lateralization movements focused on the lumbar spine. To validate its reproducibility, we conducted a test-retest involving 37 healthy volunteers, yielding results to build a minimal detectable change (MDC) graph map that would allow us to see if changes in certain variables of LBP patients are significant in relation to their recovery. Subsequently, we evaluated its applicability by having 30 LBP patients perform the movement's test before and after treatment (15 received deep oscillation therapy; 15 underwent conventional therapy) and compared the outcomes with a specialist's evaluations. The test-retest results demonstrated high reproducibility, especially in variables such as range of motion, flexion and extension ranges, as well as velocities of lumbar movements, which stand as the more important variables that are correlated with LBP disability, thus changes in them may be important for patient recovery. Among the 30 patients, the specialist's evaluations were confirmed using a low-back-specific Short Form (SF)-36 Physical Functioning scale, and agreement was observed, in which all patients improved their well-being after both treatments. The results from the specialist analysis coincided with changes exceeding MDC values in the expected variables. In conclusion, the BackMov test offers sensitive variables for tracking mobility recovery from LBP, enabling objective assessments of improvement. This test has the potential to enhance decision-making and personalized patient monitoring in LBP management.

What's the clinical significance of VAS, AOFAS, and SF-36 in progressive collapsing foot deformity.

BACKGROUND: This study aimed to ascertain the minimal clinically important difference (MCID), and substantial clinical benefit (SCB) of the American Orthopedic Foot and Ankle Society (AOFAS) scale, visual analog scale (VAS) for pain, and Short Form-36 Health Survey (SF-36) in progressive collapsing foot deformity (PCFD) surgery. METHODS: In this retrospective cohort study, a total of 84 patients with PCFD (84 feet) who underwent surgery between July 2015 and April 2021 were included. The study assessed the patients' subjective perception, as well as their VAS, AOFAS, and SF-36 scores at a minimum two-year follow-up, and these data were subjected to statistical analysis. The study utilized Spearman correlation analysis to determine the degree of correlation between patients' subjective perception and their VAS, AOFAS, and SF-36 scores. The minimal detectable change (MDC), MCID, and SCB for VAS, AOFAS, and SF-36 were calculated using both distribution- and anchor-based methods. The classification outcomes obtained from the distribution- and anchor-based methods were assessed using Cohen's kappa. RESULTS: Based on the subjective perception of the patients, a total of 84 individuals were categorized into three groups, with 7 in the no improvement group, 14 in the minimum improvement group, and 63 in the substantial improvement group. Spearman's correlation analysis indicated that the patients' subjective perception exhibited a moderate to strong association with VAS, AOFAS, SF-36 PCS, and SF-36 MCS, with all coefficients exceeding 0.4. The MCID of VAS, AOFAS, SF-36 PCS, and SF-36 MCS in PCFD surgery were determined to be 0.93, 5.84, 4.15, and 4.10 points using the distribution-based method and 1.50, 10.50, 8.34, and 3.03 points using the anchor-based method. The SCB of VAS, AOFAS, SF-36 PCS, and SF-36 MCS in PCFD surgery were 2.50, 18.50, 11.88, and 6.34 points, respectively. Moreover, the preliminary internal validation efforts have demonstrated the practical application and clinical utility of these findings. With the exception of the distribution-based MCID of SF-36 PCS, which showed fair agreement, all other measures demonstrated moderate to almost perfect agreement. CONCLUSIONS: The MDC, MCID, and SCB intuitively enhance the interpretation of VAS, AOFAS, and SF-36 in PCFD surgery, assisting all stakeholders to better understand the therapeutic benefits and limitations of clinical care, and thus to make a more rational decision. Each of these parameters has its own emphasis and complements the others. These parameters are recommended for evaluating the clinical relevance of the results, and their promotion should extend to other areas of foot and ankle surgery.

Validity and reliability of the Patient-Reported Outcomes Measurement Information System (PROMIS®) using computerized adaptive testing in patients with advanced chronic kidney disease.

BACKGROUND: The Patient-Reported Outcomes Measurement Information System (PROMIS®) has been recommended for computerized adaptive testing (CAT) of health-related quality of life. This study compared the content, validity, and reliability of seven PROMIS CATs to the 12-item Short-Form Health Survey (SF-12) in patients with advanced chronic kidney disease. METHODS: Adult patients with chronic kidney disease and an estimated glomerular filtration rate under 30 mL/min/1.73 m2 who were not receiving dialysis treatment completed seven PROMIS CATs (assessing physical function, pain interference, fatigue, sleep disturbance, anxiety, depression, and the ability to participate in social roles and activities), the SF-12, and the PROMIS Pain Intensity single item and Dialysis Symptom Index at inclusion and 2 weeks. A content comparison was performed between PROMIS CATs and the SF-12. Construct validity of PROMIS CATs was assessed using Pearson's correlations. We assessed the test-retest reliability of all patient-reported outcome measures by calculating the intraclass correlation coefficient and minimal detectable change. RESULTS: In total, 207 patients participated in the study. A median of 45 items (10 minutes) were completed for PROMIS CATs. All PROMIS CATs showed evidence of sufficient construct validity. PROMIS CATs, most SF-12 domains and summary scores, and Dialysis Symptom Index showed sufficient test-retest reliability (intraclass correlation coefficient ≥ 0.70). PROMIS CATs had a lower minimal detectable change compared with the SF-12 (range, 5.7-7.4 compared with 11.3-21.7 across domains, respectively). CONCLUSION: PROMIS CATs showed sufficient construct validity and test-retest reliability in patients with advanced chronic kidney disease. PROMIS CATs required more items but showed better reliability than the SF-12. Future research is needed to investigate the feasibility of PROMIS CATs for routine nephrology care.

Psychometric properties of a standardized protocol of muscle strength assessment by hand-held dynamometry in healthy adults: a reliability study.

BACKGROUND: Maximal isometric muscle strength (MIMS) assessment is a key component of physiotherapists' work. Hand-held dynamometry (HHD) is a simple and quick method to obtain quantified MIMS values that have been shown to be valid, reliable, and more responsive than manual muscle testing. However, the lack of MIMS reference values for several muscle groups in healthy adults with well-known psychometric properties limits the use and the interpretation of these measures obtained with HHD in clinic. OBJECTIVE: To determine the intra- and inter-rater reliability, standard error of measurement (SEM) and minimal detectable change (MDC) of MIMS torque values obtained with HHD. METHODS: Intra and Inter-rater Reliability Study. The MIMS torque of 17 muscle groups was assessed by two independent raters at three different times in 30 healthy adults using a standardized HHD protocol using the MEDup™ (Atlas Medic, Québec, Canada). Participants were excluded if they presented any of the following criteria: 1) participation in sport at a competitive level; 2) degenerative or neuromusculoskeletal disease that could affect torque measurements; 3) traumatic experience or disease in the previous years that could affect their muscle function; and 4) use of medication that could impact muscle strength (e.g., muscle relaxants, analgesics, opioids) at the time of the evaluation. Intra- and inter-rater reliability were determined using two-way mixed (intra) and random effects (inter) absolute agreement intraclass correlation coefficients (ICC: 95% confidence interval) models. SEM and MDC were calculated from these data. RESULTS: Intra- and inter-rater reliability were excellent with ICC (95% confidence interval) varying from 0.90 to 0.99 (0.85-0.99) and 0.89 to 0.99 (0.55-0.995), respectively. Absolute SEM and MDC for intra-rater reliability ranged from 0.14 to 3.20 Nm and 0.38 to 8.87 Nm, respectively, and from 0.17 to 5.80 Nm and 0.47 to 16.06 Nm for inter-rater reliability, respectively. CONCLUSIONS: The excellent reliability obtained in this study suggest that the use of such a standardized HHD protocol is a method of choice for MIMS torque measurements in both clinical and research settings. And the identification of the now known metrological qualities of such a protocol should encourage and promote the optimal use of manual dynamometry.

KeepRunning: A MoCap-Based Rapid Test to Prevent Musculoskeletal Running Injuries.

The worldwide popularisation of running as a sport and recreational practice has led to a high rate of musculoskeletal injuries, usually caused by a lack of knowledge about the most suitable running technique for each runner. This running technique is determined by a runner's anthropometric body characteristics, dexterity and skill. Therefore, this study aims to develop a motion capture-based running analysis test on a treadmill called KeepRunning to obtain running patterns rapidly, which will aid coaches and clinicians in assessing changes in running technique considering changes in the study variables. Therefore, a review and proposal of the most representative events and variables of analysis in running was conducted to develop the KeepRunning test. Likewise, the minimal detectable change (MDC) in these variables was obtained using test-retest reliability to demonstrate the reproducibility and viability of the test, as well as the use of MDC as a threshold for future assessments. The test-retest consisted of 32 healthy volunteer athletes with a running training routine of at least 15 km per week repeating the test twice. In each test, clusters of markers were placed on the runners' body segments using elastic bands and the volunteers' movements were captured while running on a treadmill. In this study, reproducibility was defined by the intraclass correlation coefficient (ICC) and MDC, obtaining a mean value of ICC = 0.94 ± 0.05 for all variables and MDC = 2.73 ± 1.16° for the angular kinematic variables. The results obtained in the test-retest reveal that the reproducibility of the test was similar or better than that found in the literature. KeepRunning is a running analysis test that provides data from the involved body segments rapidly and easily interpretable. This data allows clinicians and coaches to objectively provide indications for runners to improve their running technique and avoid possible injury. The proposed test can be used in the future with inertial motion capture and other wearable technologies.

Assessment of measurement precision in single-voxel spectroscopy at 7 T: Toward minimal detectable changes of metabolite concentrations in the human brain in vivo.

PURPOSE: To introduce a study design and statistical analysis framework to assess the repeatability, reproducibility, and minimal detectable changes (MDCs) of metabolite concentrations determined by in vivo MRS. METHODS: An unbalanced nested study design was chosen to acquire in vivo MRS data within different repeatability and reproducibility scenarios. A spin-echo, full-intensity acquired localized (SPECIAL) sequence was employed at 7 T utlizing three different inversion pulses: a hyperbolic secant (HS), a gradient offset independent adiabaticity (GOIA), and a wideband, uniform rate, smooth truncation (WURST) pulse. Metabolite concentrations, Cramér-Rao lower bounds (CRLBs) and coefficients of variation (CVs) were calculated. Both Bland-Altman analysis and a restricted maximum-likelihood estimation (REML) analysis were performed to estimate the different variance contributions of the repeatability and reproducibility of the measured concentration. A Bland-Altmann analysis of the spectral shape was performed to assess the variance of the spectral shape, independent of quantification model influences. RESULTS: For the used setup, minimal detectable changes of brain metabolite concentrations were found to be between 0.40 µmol/g and 2.23 µmol/g. CRLBs account for only 16 % to 74 % of the total variance of the metabolite concentrations. The application of gradient-modulated inversion pulses in SPECIAL led to slightly improved repeatability, but overall reproducibility appeared to be limited by differences in positioning, calibration, and other day-to-day variations throughout different sessions. CONCLUSION: A framework is introduced to estimate the precision of metabolite concentrations obtained by MRS in vivo, and the minimal detectable changes for 13 metabolite concentrations measured at 7 T using SPECIAL are obtained.

Assessment of the determinants of changes and test-retest reliability in the 6-min walk test performance over a 4-month period in healthy 6-12-year-old children.

PURPOSE: The purpose of the study is to establish the determinants of change in 6-min walk test (6MWT) performance observed in children aged 6-12 years over a 4-month period, and to provide test-retest reliability (4 months) to establish the minimal detectable change (MDC). METHODS: Healthy children aged 6-12 years performed two 6MWT trials separated by a period of 4 months. Multiple linear regression analysis was performed to estimate the percentage of variance explained by the variables potentially predictive of the change in the 6MWT. We employed the intraclass correlation coefficient to assess test-retest reliability. RESULTS: Fifty-nine children (28 boys and 31 girls) were assessed. The change in distance covered during the 6MWT was significantly correlated with the growth in their height (r = 0.679; p < 0.05) and the change in their weight (r = 0.473; p < 0.05). Multiple linear regression analysis shows that the change in distance covered in the 6MWT was only explained by its growth in height (46.0% explained variance). The test-retest reliability was fair-good. After 4 months, we established a 12% change from the initial measurement (79.69 m) as the MDC for a 90% confidence level (MDC90). CONCLUSIONS: The distance covered in the 6MWT improved as the children's age, weight and height increased. The growth children's height was the most important predictor of change in distance covered in the 6MWT. An increase of at least 79.69 m (MDC90) in distance covered in the 6MWT is necessary to attribute the improvement to an intervention and not to the individual's growth.

Minimal detectable change of the disc-fovea angle for ocular torsion assessment.

PURPOSE: The disc-fovea angle (DFA) is used as a relevant indicator of ocular torsion change in cyclovertical strabismus. However, interpretation of the variation in time must differentiate whether a real change has occurred or if the disparity is due to random measurement error. The aim of the study was to obtain the minimal detectable change (MDC) of the DFA. It represents the minimal variation between two measurements that may be considered a real ocular torsion change. METHODS: A prospective cross-sectional study was conducted in San Carlos Clinical Hospital of Madrid, Spain. Sixty healthy right eyes from 60 patients (31 men and 29 women) were recruited. Three digital fundus photographs were obtained, and between measurements, the patient moved their head away from the head support and then returned. Two observers quantified the DFA with software designed with MATLAB. Test-retest and interrater reliability were calculated. RESULTS: Mean participant age was 56.1 years (SD 16.6, range 25-85). Mean DFA was 8.1° (SD 3.5, range 1.3-18.5). Test-retest reliability for Observer 1 (Ob1), Observer 2 (Ob2) and interrater reliability were excellent (ICC 0.80, 0.83 and 0.95, respectively). Precision was 2.9° (Ob1) and 3.0° (Ob2), and the MDC95 was 4.1° (Ob1) and 4.2° (Ob2). Bland-Altman analysis revealed an absence of bias and a homoscedastic distribution of the differences. CONCLUSIONS: The MDC of the DFA in fundus photography was 4°, which represents the minimal change that may be considered a real change in ocular torsion. This result may improve the interpretation of ocular torsion changes in surgery and clinical scenarios.

Detecting subtle mobility changes among older adults: the Quantitative Timed Up and Go test.

BACKGROUND: The Quantitative Timed Up and Go (QTUG) test uses wearable sensors, containing a triaxial accelerometer and an add-on triaxial gyroscope, to quantify performance during the TUG test with potential to capture more minor changes in mobility. AIMS: To examine the responsiveness, minimum detectable change (MDC) and observed effect size of QTUG in a cohort of socially active adults aged 50 years and over participating in a structured community exercise program. METHODS: 54 participants (91% females, mean age 63.6 ± 6.5 years) completed repeated QTUG testing under single- and dual-task conditions. Responsiveness of the QTUG was assessed by correlation of change in standard TUG with QTUG change (Pearson's correlation coefficient). MDC and effect sizes (standardized mean difference and Cohen's d) were also calculated for QTUG. RESULTS: There was a strong positive correlation between change in the standard TUG and change in QTUG (single task r = 0.91, p < 0.001). MDC in QTUG was calculated as 0.77 (Sd, 1.39; ICC 0.96) seconds (single task) and 2.33 (Sd 2.18; ICC 0.85) seconds (dual task). Several QTUG parameters showed improvements in mean values with small effect sizes (sit -to-stand transition time d = 0.418; walk time d = 0.398; cadence d = 0.306, swing time d = 0.314; step time d = 0.479; gait velocity d = 0.365; time to reach turn d = 0.322) under single-task conditions and with a moderate effect size (d = 0.549) in time taken to turn under the dual-task condition. CONCLUSION: Initial evidence of QTUG's responsiveness to change in mobility in active middle to older age adults has been demonstrated with small to moderate effect sizes observed in specific QTUG parameters.

Reliability of walking speed in basic and complex conditions in healthy, older community-dwelling individuals.

BACKGROUND: There is a paucity of reliability data for walking speed tests in complex conditions to assess functioning in healthy older individuals. AIMS: To evaluate the absolute intra- and intertest reliability of walking speed performed in basic and complex conditions in healthy older individuals. METHODS: Fifty-two men and women of mean age 69.7 ± 3.2 years were tested for habitual and maximal walking speed. Maximal speed was also assessed under different conditions, including walking on a path of reduced width; picking up objects; stepping over hurdles; stepping over hurdles wearing sunglasses and finally, carrying a box. Two testing sessions (separated by 4 weeks) of two trials each were administered. Reliability was analysed by intra-class correlation coefficient (ICC), minimal detectable change (MDC) and Bland-Altman plots with limits of agreement (LOA). RESULTS: Intrasession ICCs ranged from good to excellent (0.89-0.95) except for picking up objects (0.44). Intersession ICCs were moderate to good (0.60-0.78) and %MDCs were acceptable (14-24%). Bland-Altman plots suggested a good agreement between the two testing sessions at group level (mean differences from - 0.02 to - 0.11 m/s), and limited agreement between testing sessions at individual level (upper LOA from 0.13 to 0.37 m/s and lower LOA from - 0.29 to - 0.49 m/s). CONCLUSIONS: Complex walking speed tests are generally reliable measures displaying good and moderate intra- and inter-session reliability. Such tests seem a more suitable functional assessment tool for heathy older subjects compared with simple walking. Some learning effect may be present and further reliability studies are needed.

Marker Placement Reliability and Objectivity for Biomechanical Cohort Study: Healthy Aging in Industrial Environment (HAIE-Program 4).

In large cohort studies, due to the time-consuming nature of the measurement of movement biomechanics, more than one evaluator needs to be involved. This may increase the potential occurrence of error due to inaccurate positioning of markers to the anatomical locations. The purpose of this study was to determine the reliability and objectivity of lower limb segments length by multiple evaluators in a large cohort study concerning healthy aging in an industrial environment. A total of eight evaluators performed marker placements on five participants on three different days. Evaluators placed markers bilaterally on specific anatomical locations of the pelvis, thigh, shank and foot. On the right foot, markers were placed in anatomical locations to define a multi-segmental foot model. The position of the marker at the anatomical locations was recorded by a motion capture system. The reliability and objectivity of lower limb segment lengths was determined by the intraclass correlation coefficient of a two-way random model and of the two-way mixed model, respectively. For all evaluators for all segments, the average reliability and objectivity was greater than 0.8, except for the metatarsus segment (0.683). Based on these results, we can conclude that multiple evaluators can be engaged in a large cohort study in the placement of anatomical markers.

Minimal detectable change in handgrip strength and usual and maximum gait speed scores in community-dwelling Japanese older adults requiring long-term care/support.

Aging is an important issue in Japan that has led to a large number of older adults requiring long-term care/support. Therefore, we determined the range of measurement error in the measurement of handgrip strength and gait speed which are representative tests. This cross-sectional study included 111 community-dwelling Japanese older adults aged ≥65 years who required long-term care/support and underwent ambulatory rehabilitation. Handgrip strength and usual and maximum gait speed were measured on two days in one single week. Minimal detectable change (MDC) was calculated. The MDC in handgrip strength was 2.9 kg for the overall population, 3.2 kg for the male participants, and 2.4 kg for the female participants. For the overall population, the MDC in usual gait speed was 0.18 m/s and that in maximum gait speed was 0.23 m/s. These MDCs are expected to be suitable for judging clinical changes because this study considered gender and typical tests.

Test-retest reliability and minimal detectable change of corticospinal tract integrity in chronic stroke.

Diffusion tensor imaging (DTI) can be used to index white matter integrity of the corticospinal tract (CST) after stroke; however, the psychometric properties of DTI-based measures of white matter integrity are unknown. The purpose of this study was to examine test-retest reliability as determined by intraclass correlation coefficients (ICC) and calculate minimal detectable change (MDC) of DTI-based measures of CST integrity using three different approaches: a Cerebral Peduncle approach, a Probabilistic Tract approach, and a Tract Template approach. Eighteen participants with chronic stroke underwent DTI on the same magnetic resonance imaging scanner 4 days apart. For the Cerebral Peduncle approach, a researcher hand drew masks at the cerebral peduncle. For the Probabilistic Tract approach, tractography was seeded in motor areas of the cortex to the cerebral peduncle. For the Tract Template approach, a standard CST template was transformed into native space. For all approaches, the researcher performing analyses was blind to participant number and day of data collection. All three approaches had good to excellent test-retest reliability for fractional anisotropy (FA; ICCs >0.786). Mean diffusivity, axial diffusivity, and radial diffusivity were less reliable than FA. The ICC values were highest and MDC values were the smallest for the most automated approach (Tract Template), followed by the combined manual/automated approach (Probabilistic Tract) then the manual approach (Cerebral Peduncle). The results of this study may have implications for how DTI-based measures of CST integrity are used to define impairment, predict outcomes, and interpret change after stroke.

A comparison between the low back pain scales for patients with lumbar disc herniation: validity, reliability, and responsiveness.

BACKGROUND: Although the Japanese Orthopedic Association Back Pain Evaluation Questionnaire (JOABPEQ), Numerical Pain Rating Scale (NPRS), Oswestry Disability Index (ODI), Roland Morris Disability Questionnaire (RMDQ), and Short Form 36 Health Survey (SF-36) has shown a preferable psychometric properties in patients with low back pain (LBP), but no study has yet determined these in conservative treatment of patients with lumbar disc herniation (LDH). Thus the current study aimed to compare those scales in LDH patients receiving conservative treatment to select the better option to assess the severity of disease. METHODS: LDH patients were invited to complete the JOABPEQ, NPRS, ODI, RMDQ, and SF-36 twice. The internal consistency was evaluated by the Cronbach's α. Test-retest reliability was tested by the intraclass correlation coefficient (ICC). The relationships of these scales were evaluated by the Pearson correlation coefficients (r). The responsiveness was operationalised using the receiver operating characteristic (ROC) curve, as well as the comparison of smallest detectable change (SDC), minimum important change (MIC). RESULTS: A total of 353 LDH patients were enrolled. Four subscales of the Chinese JOABPEQ were over 0.70, then the ICCs for the test-retest reliability were over 0.75. For functional status, remarked negative correlations could be seen between JOABPEQ Q2-Q4 and ODI, as well as RMDQ (r = - 0.634 to - 0.752). For general health status, remarkable positive correlations could also be seen between Q5 Mental health and SF-36 PCS (r = 0.724) as well as SF-36 MCS (r = 0.736). Besides, the area under of the curves (AUC) of the JOABPEQ ranged from 0.743 to 0.827, indicating acceptale responsiveness, as well as the NPRS, ODI, and RMDQ. CONCLUSION: NPRS, and ODI or RMDQ is recommended in studies related to LDH patients, while if the quality of life also is needed to observe, the NPRS, and JOABPEQ would be more appropriate rather than SF-36.

What Are the Minimal Detectable Changes in SDMT and Verbal Fluency Tests for Assessing Changes in Cognitive Performance in Persons with Multiple Sclerosis and Non-Multiple Sclerosis Controls?

INTRODUCTION: Cognitive impairment is frequent in persons with multiple sclerosis (PwMS) and can impact on activities of daily living. The capacity to differentiate real changes from background statistical noise induced by human, instrumentational, and environmental variations inherent to the evaluation would improve cognitive assessments. OBJECTIVE: To assess the short-term reproducibility of cognitive tests in non-multiple sclerosis (non-MS) persons and PwMS. METHODS: Sixty-two PwMS and 19 non-MS persons performed 2 measurements, 1 week apart, of the Symbol Digit Modalities Test (SDMT) and phonological and semantic verbal fluency. Test-retest reliability was evaluated by the intraclass correlation coefficients (ICC) and agreement by standard error of measurement (SEM) and minimum detectable change (MDC). RESULTS: The reliability of the cognitive variables studied had moderate to high ICC values (ICC > 0.8) in both populations. The threshold to consider a significant cognitive modification evaluated by SEM and MDC was lower in PwMS compared with non-MS persons. CONCLUSIONS: SDMT and verbal fluency have good short-term reproducibility in PwMS. Specific SEM and MDC cutoffs based on the same design of evaluation (especially retest timing) and to the targeted pathological population (MS vs. healthy) should systematically be used to consider cognitive modification as significant in research protocol as well as in clinical practice.