The relative and absolute reliability of two balance performance measures in chronic stroke patients

Purpose. To examine the relative reliability and absolute reliability of the Berg Balance Scale (BBS) and the Postural Assessment Scale for Stroke Patients (PASS) in chronic stroke patients.

Method. A total of 52 mild to moderate stroke patients, who had a stroke more than 6 months previously, participated in the study. Both balance measures were administered twice, seven days apart, to the patients. A relative reliability index (intra-class correlation coefficient, ICC_2,1) was used to examine the level of agreement between test and retest. Absolute reliability indices, including the Bland and Altman method, the standard error of measurement (SEM), and the smallest real differences (SRD), were used to define the extent to which a balance score varies on test-retest measurements.

Results. Test-retest agreements were high (ICC_2,1: BBS = 0.98; PASS = 0.97), indicating excellent agreement from a relative perspective. The SEM of the BBS and PASS, representing the smallest change threshold that indicates a real improvement for a group of individuals, were 2.4 and 1.1, respectively. The SRD of the BBS and PASS were 6.7 and 3.2, respectively, exhibiting the smallest change threshold that indicates a real improvement for a single individual.

Conclusions. The test-retest agreements of the BBS and PASS were high in mild to moderate chronic stroke patients. The thresholds of both measures to detect real change are acceptable in research and clinical settings.     

Reliability of gait performance tests in men and women with hemiparesis after stroke.

OBJECTIVE: To assess the reliability of 6 gait performance tests in individuals with chronic mild to moderate post-stroke hemiparesis. Design: An intra-rater (between occasions) test-retest reliability study. Subjects: Fifty men and women (mean age 58+/-6.4 years) 6-46 months post-stroke. METHODS: The Timed "Up & Go" test, the Comfortable and the Fast Gait Speed tests, the Stair Climbing ascend and descend tests and the 6-Minute Walk test were assessed 7 days apart. Reliability was evaluated with the intraclass correlation coefficient (ICC(2,1)), the Bland & Altman analysis, the standard error of measurement (SEM and SEM%) and the smallest real difference (SRD and SRD%). RESULTS: Test-retest agreements were high (ICC(2,1) 0.94-0.99) with no discernible systematic differences between the tests. The standard error of measurement (SEM%), representing the smallest change that indicates a real (clinical) improvement for a group of individuals, was small (< 9%). The smallest real difference (SRD%), representing the smallest change that indicates a real (clinical) improvement for a single individual, was also small (13-23%). CONCLUSION: These commonly used gait performance tests are highly reliable and can be recommended to evaluate improvements in various aspects of gait performance in individuals with chronic mild to moderate hemiparesis after stroke.     

What change in isokinetic knee muscle strength can be detected in men and women with hemiparesis after stroke?

OBJECTIVE: To assess the intra-rater (between occasions) test-retest reliability of isokinetic knee muscle strength measurements in subjects with chronic poststroke hemiparesis and to define limits for the smallest change that indicates real (clinical) improvements for stroke patients. SUBJECTS: Fifty men and women (mean age 58 +/- 6.4 years) 6-46 months post stroke, able to walk at least 300 m with or without a unilateral assistive device. METHODS: Maximal concentric knee extension and flexion contractions at 60 degrees/s and 120 degrees/s, and maximal eccentric knee extension contractions at 60 degrees/s, with the paretic and nonparetic limbs, were performed seven days apart using a Biodex dynamometer. MEASURES: Reliability of the maximum peak torque measurements was evaluated with the intraclass correlation coefficient (ICC(2,1)), the Bland and Altman analyses, the standard error of measurement (SEM and SEM%) and the smallest real difference (SRD and SRD%). RESULTS: Test-retest agreements were high (ICC(2,1) 0.89-0.96) with no discernible systematic differences between limbs, angular velocities and modes. The SEM%, representing the smallest change that indicates a real (clinical) improvement for a group of subjects, was relatively small (8-20%). The SRD%, representing the smallest change that indicates a real improvement for a single subject ranged from 26% to 33% for concentric knee extension, from 39% to 55% for concentric knee flexion, and from 22% to 25% for eccentric knee extension. CONCLUSION: Isokinetic knee muscle strength can be reliably measured and used to detect real improvements following an intervention for single subjects as well as for groups of subjects with chronic mild to moderate hemiparesis after stroke.     

中文版躯干损伤量表评定脑卒中患者躯干功能的信度及效度研究

目的:探讨中文版躯干损伤量表(TIS)评定脑卒中患者躯干功能的信度及效度,为该量表的临床应用提供客观依据。方法:病例组和对照组各50例参加了本研究,病例组进行TIS、Fugl-Meyer中的平衡部分(FM-B)和Berg平衡量表(BBS)评定,并在2天内完成TIS第二次评定;对照组进行1次的TIS和FM-B评定。将两次TIS的结果做相关性分析测试其信度;将TIS结果与FM-B、BBS作相关性分析检验其效度。结果:TIS两次测试结果高度相关,重测信度组内相关系数(ICC)为0.899-0.971,测量者间ICC为0.843-0.973;TIS与FM-B、BBS总分高度相关(r=0.891,r=0.858);病例组和对照组的TIS总分分别为21.7±1.3分和13.5±4.3分,两者间差异具有显著性(P<0.01)。结论:中文版TIS具有良好的效度、信度和区分度,可用于脑卒中患者躯干功能的评价。     

Intra- and inter-rater reliability of a modified measure of hand behind back range of motion

The aim of this reliability study was to identify the clinimetric properties, specifically intra- and inter-rater reliability, for measuring the functionally and clinically important hand behind back (combined shoulder internal rotation/adduction and elbow flexion) range of motion using a modified technique. Sixty asymptomatic participants (20 male, 40 female) aged 45.4 ± 11.7 years (mean ± SD). Hand behind back was measured as the distance from the mid-line between the posterior superior iliac spines (PSIS) to the tip of the thumb and recorded in centimetres above the PSIS (a positive measure) or below the PSIS (a negative measure). The intra- and inter-rater reliability for the measurement were excellent, with ICC (2,1) of 0.95 for intra-rater and ICC (2,2) of 0.96 for inter-rater reliability. The standard error of the measurement (SEM) and smallest real difference (SRD) values showed acceptable levels of measurement error, SEM 4.3 mm and SRD 12.8 mm for intra-rater reliability and SEM 2.6 mm and SRD 7.7 mm for inter-rater reliability. The assessment of hand-behind-back motion from a point equidistant between the PSISs to the tip of the thumb is more reliable than traditional methods and a useful clinical tool.     

Berg balance scale: intrarater test-retest reliability among older people dependent in activities of daily living and living in residential care facilities

BACKGROUND AND PURPOSE: The Berg Balance Scale (BBS) is frequently used to assess balance in older people, but knowledge is lacking about the absolute reliability of BBS scores. The aim of this study was to investigate the absolute and relative intrarater test-retest reliability of data obtained with the BBS when it is used among older people who are dependent in activities of daily living and living in residential care facilities. SUBJECTS: The participants were 45 older people (36 women and 9 men) who were living in 3 residential care facilities. Their mean age was 82.3 years (SD=6.6, range=68-96), and their mean score on the Mini Mental State Examination was 17.5 (SD=6.3, range=4-30). METHODS: The BBS was assessed twice by the same assessor. The intrarater test-retest reliability assessments were made at approximately the same time of day and with 1 to 3 days in between assessments. Absolute reliability was calculated using an analysis of variance with a 95% confidence level, as suggested by Bland and Altman. Relative reliability was calculated using the intraclass correlation coefficient (ICC). RESULTS: The mean score was 30.1 points (SD=15.9, range=3-53) for the first BBS test and 30.6 points (SD=15.6, range=4-54) for the retest. The mean absolute difference between the 2 tests was 2.8 points (SD=2.7, range=0-11). The absolute reliability was calculated as being 7.7 points, and the ICC was calculated to .97. DISCUSSION AND CONCLUSION: Despite a high ICC value, the absolute reliability showed that a change of 8 BBS points is required to reveal a genuine change in function among older people who are dependent in activities of daily living and living in residential care facilities. This knowledge is important in the clinical setting when evaluating an individual's change in balance function over time in this group of older people.     

A comparison of psychometric properties of the smart balance master system and the postural assessment scale for stroke in people who have had mild stroke

OBJECTIVE: To compare the psychometric properties (including the test-retest reliability, responsiveness, and predictive validity) of the Smart Balance Master (SBM) system and the Postural Assessment Scale for Stroke patients (PASS) in patients with mild stroke. DESIGN: One repeated-measures design (at a 2-wk interval) was used to examine the test-retest reliability of the SBM and PASS, and another similar design was applied to investigate their responsiveness. Patients who participated in the responsiveness study were followed up approximately 1 year later, and the predictive validity of the SBM system and PASS were examined by assessing the patients' comprehensive activities of daily living (ADL) function. SETTING: Three rehabilitation units in Taiwan. PARTICIPANTS: Twenty patients with chronic stroke in the reliability study; 40 and 32 patients who had recently had a stroke in the responsiveness and predictive validity studies, respectively. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Three computerized tests of the SBM (the equilibrium score of the Sensory Organization Test, scores in rhythmic weight-shifting tests, and scores in the limits of stability test) and the PASS were used. The combination of the Barthel Index and Frenchay Activities Index was used to represent the comprehensive ADL function. RESULTS: For the SBM, all but the weight-shifting tests of the SBM had moderate to high reliability (intraclass correlation coefficient [ICC] range, .78-.91). The responsiveness of the equilibrium score and the limits of stability test were moderate (effect size [d], .63) and small (d range, .27-.33), respectively, whereas the responsiveness of the weight-shifting tests was limited (d range, .04-.29). All but the weight-shifting tests of the SBM in the second evaluation had acceptable predictive validity for comprehensive ADL function (r2 range, .15-.17). The PASS showed high reliability (ICC=.84) and small responsiveness (d=.41), and the PASS in the second evaluation had acceptable predictive validity (r2=.24). CONCLUSIONS: The PASS and the equilibrium score and limits of stability scores of the SBM had acceptable test-retest reliability, responsiveness, and predictive validity in patients with mild stroke, but the psychometric properties of the weight-shifting tests of the SBM should be further examined before consideration of their usage in patients with stroke.     

Reliability and smallest detectable change determination for serratus anterior muscle strength and endurance tests

The purposes of this study were to determine inter-tester reliability, one-week test-retest reliability and smallest detectable difference (SDD) of serratus anterior muscle strength and endurance tests. Asymptomatic subjects were tested on an apparatus designed by the investigators. During strength testing, subjects performed isometric contractions recorded by a hand-held dynamometer. For endurance testing, subjects held a dumbbell of 15% of their body weight and performed repetitions until they became fatigued. Intraclass correlation coefficients (ICC) for the strength test revealed good inter-tester reliability (ICC2,3 = .90-.93) and good one-week test-retest reliability (ICC2,3 = .83-.89). For the endurance test, ICCs showed good inter-tester reliability (ICC2,1 = .71-.76) but moderate one-week test-retest reliability (ICC2,1 = .59-.62). The SDDs at 68% confidence level ranged from 22.7 to 39.2 newtons for the strength test, and 11 to 20 repetitions for the endurance test. In summary, the technique used in the study is reliable for quantifying the SA muscle strength.     

三种量表评定脑卒中急性期患者姿势控制能力的分析研究

目的探讨3种量表在评定脑卒中急性期患者姿势控制能力方面的应用情况。方法对45例脑卒中急性期患者分别采用脑卒中患者姿势评定量表（PASS）、Fugl—Meyer平衡量表（FM—B）及Berg平衡量表（BBS）对其姿势控制能力进行评定。所有病例均评定3次，评定时间分别为脑卒中起病后1周内、起病第3周时及出院前。选用Spearman统计法分析3种量表间的相关性；并同时计算3种量表的地板效应及天花板效应。结果PASS与FM—B及BBS间均具有高度相关性（r=0.867—0．957，P〈0．01）；在本研究各次评定中，PASS无明显的地板效应和天花板效应，而FM-B和BBS在第1次评定时均存在明显的地板效应（FM—B为26．6％．BBS为26．6％）。结论PASS与FM—B及BBS均能客观反映脑卒中急性期患者的姿势控制能力，而且PASS还能对脑卒中患者的卧位姿势控制能力进行评定，故在评定脑卒中急性期患者姿势控制能力方面，PASS优于FM—B和BBS。     

Smallest real difference of 2 instrumental activities of daily living measures in patients with chronic stroke

Lu W-S, Chen CC, Huang S-L, Hsieh C-L. Smallest real difference of 2 instrumental activities of daily living measures in patients with chronic stroke.ObjectiveTo estimate the smallest real difference (SRD) values of 2 instrumental activities of daily living measures (the Nottingham Extended Activities of Daily Living [NEADL] and the Frenchay Activities Index [FAI]) in patients with chronic stroke.DesignTest-retest reliability study.SettingPhysical rehabilitation units of 5 hospitals.ParticipantsChronic stroke patients (N=52; 37 men, 15 women) who were discharged from the hospital for more than 6 months.InterventionsNot applicable.Main Outcome MeasuresBoth measures were administered twice about 2 weeks apart to participants. The SRD was calculated on the basis of standard error of measurement: SRD = 1.96 × √2 × Standard error of measurement. SRD% (the value of SRD divided by total score of a measure) was used to compare measurement errors across both measures. Reproducibility between successive measurements of the measures was investigated with intraclass correlation coefficients (ICCs).ResultsThe SRD (SRD%) values of the NEADL and the FAI were 12.0 (21.1%) and 6.7 (14.9%), respectively. Test-retest reproducibility of both measures was high (ICC: NEADL=.89, FAI=.89).ConclusionsBecause of substantial SRD values of the NEADL and the FAI, prospective users should be cautious in using both measures to detect real change for a single subject.     

Psychometric properties of 2 simplified 3-level balance scales used for patients with stroke

BACKGROUND AND PURPOSE: To determine if the 3-level scales yield data as reliable and valid as data obtained for the original scales, 2 simplified 3-level measures of balance--a modified Berg Balance Scale (BBS-3P) and a modified Postural Assessment Scale for Stroke Patients (PASS-3P)--were proposed by the researchers, and psychometric properties of each were compared with those of the original measures (the Berg Balance Scale [BBS] and the Postural Assessment Scale for Stroke Patients [PASS], respectively) in patients with stroke. SUBJECTS AND METHODS: The study consisted of 2 parts. The first part examined the reliability and concurrent and convergent validity of measurements obtained with these instruments. A total of 77 patients participated in this part of the study. The 3 levels in the center of the BBS were collapsed to a single level (ie, 0-2-4) to form the BBS-3P. Similarly, the 2 middle scores of the center of the PASS were averaged (ie, 0-1.5-3) to form the PASS-3P. In the second part of the study, the predictive validity and responsiveness of these measures were examined. The BBS and PASS scores of 226 patients were retrieved from the records of participants in the Quality of Life After Stroke Study, and these scores were converted into the proposed BBS-3P and PASS-3P scores. RESULTS: The BBS-3P and PASS-3P showed high concurrent validity with the BBS and PASS, good predictive validity for disability, and moderate to high responsiveness. Importantly, the psychometric properties of the BBS-3P and PASS-3P were essentially identical to those of the original BBS and PASS. DISCUSSION AND CONCLUSION: The psychometric properties of both simplified 3-level balance measures were comparable to those of the full, nontruncated scales. Future study is needed to investigate how much meaningful utility can be gained from the scheme of simplification of scaling.     

Reliability of the clinical outcome variables scale when administered via telephone to assess mobility in people with spinal cord injury

OBJECTIVE: To examine the equivalence reliability and test-retest reliability of the Clinical Outcome Variables Scale (COVS) when administered via telephone (TCOVS) to people with spinal cord injury (SCI). DESIGN: Equivalence (telephone administration vs in-person) and test-retest reliability study. SETTING: Assessments conducted in participants' home environment. PARTICIPANTS: Equivalence reliability was examined in a convenience sample of 37 people with a diagnosis of traumatic SCI who had been discharged from the Queensland Spinal Injuries Unit to the community. In a separate group of participants, test-retest reliability of COVS when administered via telephone was examined in 43 people with SCI who were randomly selected from the Queensland Spinal Cord Injuries Service records. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Reliability was assessed at the subscale and composite score level using intraclass correlation coefficients (ICC(2,1)) and Bland-Altman limits of agreement. RESULTS: Reliability was good for TCOVS and COVS for the composite score (ICC=.98), mobility subscale (ICC=.97), and ambulation subscale (ICC=.99). Reliability was also good for TCOVS test and retest assessments for the composite score (ICC=1), mobility subscale (ICC=1), and ambulation subscale (ICC=1). For all comparisons, most data points were within the 95% limits of agreement and the width of limits of agreement were considered to be clinically acceptable. CONCLUSIONS: The study findings confirm the equivalence and test-retest reliability of the TCOVS in an SCI population when administered by trained raters.     

Does Magnetic Resonance Imaging Provide Superior Reliability for Achilles and Patellar Tendon Cross-Sectional Area Measurements Compared with Ultrasound Imaging?

This study investigated the reliability of Achilles and patellar tendon cross-sectional area (CSA) measurement using ultrasound imaging (USI) and magnetic resonance imaging (MRI). Fifteen healthy adults were imaged twice on two occasions, interrupted by a tendon loading protocol. Tendon CSA segmentations were conducted by an experienced and an inexperienced rater blinded to information regarding subject, session and loading status. USI provided good test-retest reliability (intra-class correlation coefficient [ICC] 2,1 > 0.85, standard error of measurement [SEM] 5%–6%), while with MRI it was excellent (ICC 2,1 > 0.92, SEM 4%) for the experienced rater. This study suggests that MRI provides superior reliability for tendon CSA measurements compared with USI. However, the difference in reliability between the methods was small, and the results were inconclusive regarding objectivity and sensitivity to change when assessed based on the effect of loading. We concluded that both methods can be used for reliable CSA measurements of the Achilles and patellar tendons when using a highly standardized measurement protocol and when conducted by an experienced rater.     

Reliability of isokinetic ankle dorsiflexor strength measurements in healthy young men and women

The purposes of this study were: (i) to determine the test-retest reliability of isokinetic ankle dorsiflexor strength measurements in young healthy adults using the Biodex dynamometer, and (ii) to examine several statistical measures for the interpretation of reliability. Thirty men and women (mean age 23 +/- 3 years) performed three maximal concentric contractions at 30 degrees/s, 60 degrees/s, 90 degrees/s, 120 degrees/s and 150 degrees/s. Reliability of peak torque, work and torque at a specific time were assessed by calculating the intraclass correlation coefficient (ICC 2,1), Pearson product moment correlation coefficient (r), standard error of the measurement (SEM), method error (ME) and coefficient of variation (CV), and by plotting the differences between observations against their means. Isokinetic tests of ankle dorsiflexor strength in healthy young adults using the Biodex dynamometer were highly reliable (ICC 0.61-0.93). It is recommended that test-retest reliability analyses include the ICC and assessments of measurement errors (SEM, ME or CV), as well as graphs to indicate any systematic variations in the data.     

Evaluation of the Swedish version of the Modified Elderly Mobility Scale (Swe M-EMS) in patients with acute stroke

OBJECTIVE: To investigate the inter-rater reliability and validity of the Swedish version of the Modified Elderly Mobility Scale (Swe M-EMS). DESIGN: A correlation study. SETTING: A stroke unit which provides acute care and rehabilitation for all stroke admissions in Northern Alvsborg County Hospital, Sweden. SUBJECTS: Thirty consecutive patients with an acute first-time stroke. Seventeen were women and 13 were men, with a median age of 79 years (41-92) and with a median hospital stay of 21 days (8-35). INTERVENTION: The patients were assessed twice with the Swe M-EMS on admission and at discharge, before and after midday, by two independent physiotherapists. They were assessed by an independent physiotherapist using the three evaluation instruments on admission, once a week during their hospital stay and at discharge. MAIN OUTCOME MEASURES: The primary evaluation instrument was the Swe M-EMS. The two other evaluation instruments were the Modified Motor Assessment Scale of Uppsala Akademiska Sjukhus-95 (M-MAS UAS-95) and the Berg Balance Scale (BBS). RESULTS: The Swe M-EMS was a reliable instrument (ICC 0.98-0.99). It correlated well with both the M-MAS UAS-95 (r(s) = 0.69-0.88) and the BBS (r(s) = 0.86-0.94). The Swe M-EMS was sensitive to change over time, but the patients obtained the maximum score quickly. CONCLUSION: The instrument shows a high inter-rater reliability. The Swe M-EMS correlates well with both the M-MAS UAS-95 and the BBS and is sensitive to change. However, it is not sensitive enough to use as a single instrument in evaluating the improvement of a patient with acute stroke.     

The Orpington Prognostic Scale for patients with stroke: reliability and pilot predictive data for discharge destination and therapeutic services

PURPOSE: To determine the inter-rater and test-retest reliability of the Orpington Prognostic Scale (OPS) in patients with stroke. Pilot data were gathered to evaluate its predictive validity for discharge destination and therapeutic services required on discharge.METHOD: Ninety-four consecutive patients, admitted to hospital due to stroke participated. Pairs of physiotherapists (PT) and occupational therapists (OT) assessed patients using the OPS on days 7 and 14 post stroke. For inter-rater reliability, one rater performed the OPS while the other observed, each scoring the scale independently. For test-retest reliability, two different raters tested the subjects separately within the same day. Data were gathered on the discharge destination and the number of follow-up services prescribed.RESULTS: The inter-rater reliability as measured by the intraclass correlation coefficient (ICC) was 0.99 (95% CI 0.97 - 0.99). For test-retest reliability, the ICC was 0.95 (95% CI 0.90 - 0.98). The accuracy for predicting discharge to home using OPS 5.0 was 65% (95% CI 0.52 - 0.76). OPS scores were not related to number of follow-up services prescribed.CONCLUSIONS: Despite high inter-rater and test-retest reliability, the OPS has limited predictive accuracy for discharge destination and is a poor predictor of follow-up services.     

Reliability study of measurements for lymphedema in breast cancer patients

OBJECTIVE: Water displacement, circumference measurement, and tissue tonometry are important methods to evaluate the status of lymphedemous limbs in breast cancer patients. The purpose of this study was to investigate the reliabilities, and define the limits for clinical change indicative of clinical improvement with respect to these three measures. DESIGN: Fourteen patients were recruited for water displacement and circumference measurement, and 17 for tissue resistance by tonometry. All had been treated for breast cancer and subsequently developed lymphedema. Two physical therapists conducted the measurements to determine intra- and interrater reliability. RESULTS: All measures had fair to excellent reliability (water displacement and circumference measurement, intraclass correlation coefficient [ICC] >0.99, P < 0.05; tissue tonometry, 0.66 < ICC < 0.88, P < 0.05). There was no systematic change in the mean for any of the measures. The variation, as determined by standard error of measurement (SEM), SEM%, smallest real difference (SRD), and SRD% was greatest for tissue tonometry. CONCLUSIONS: Water displacement and circumference measurement (but not tonometry) are reliable techniques for assessing lymphedema in clinical practice. The effect of modifying the tonometry protocol and increasing the amount of rater training should be studied to determine whether the reliability of this method can be improved.     

Effect of space balance 3D training using visual feedback on balance and mobility in acute stroke patients

[Purpose] The purpose of the study was to determine the effects of balance training with Space Balance 3D, which is a computerized measurement and visual feedback balance assessment system, on balance and mobility in acute stroke patients. [Subjects and Methods] This was a randomized controlled trial in which 52 subjects were assigned randomly into either an experimental group or a control group. The experimental group, which contained 26 subjects, received balance training with a Space Balance 3D exercise program and conventional physical therapy interventions 5 times per week during 3 weeks. Outcome measures were examined before and after the 3-week interventions using the Berg Balance Scale (BBS), Timed Up and Go (TUG) test, and Postural Assessment Scale for Stroke Patients (PASS). The data were analyzed by a two-way repeated measures ANOVA using SPSS 19.0. [Results] The results revealed a nonsignificant interaction effect between group and time period for both groups before and after the interventions in the BBS score, TUG score, and PASS score. In addition, the experimental group showed more improvement than the control group in the BBS, TUG and PASS scores, but the differences were not significant. In the comparisons within the groups by time, both groups showed significant improvement in BBS, TUG, and PASS scores. [Conclusion] The Space Balance 3D training with conventional physical therapy intervention is recommended for improvement of balance and mobility in acute stroke patients.Key words: Balance training, Visual feedback, Acute stroke patients