A comparison of responsiveness and predictive validity of two balance measures in patients with stroke

Postural Maintenance Is Associated With Walking Ability in People Receiving Acute Rehabilitation After a Stroke

OBJECTIVES

The Postural Assessment Scale for Stroke Patients (PASS) assesses the ability of people post stroke to maintain or change a given posture from lying to standing, and the items on which people with different walking status perform differently may suggest potential interventions. The purpose of this study was to (1) examine the association of PASS scores at admission for acute rehabilitation with walking status at admission and 3 months post stroke (3 M), and (2) identify PASS items that discriminate walking status.

METHODS

In this prospective observational study, 93 people post stroke were assessed with the PASS and a 2.44-m gait speed test at admission, with walking status assessed by telephone interview at 3 M. Those who could walk over a 2.44-m distance without the assistance of a walking aid or another person were considered to be independent in walking; others were considered to be dependent. Those who were dependent at admission were divided into the "regained independence" and "remained dependent" groups based on their status at 3 M. The association of the PASS at admission with 3 levels of walking status (independent at admission, regained independence, and remained dependent) was examined using the Kruskal-Wallis test. For those dependent at admission, the association of PASS score at admission with walking status at 3 M was examined using logistic regression and receiver operating curve analysis.

RESULTS

PASS scores at admission differed significantly across the 3 walking status groups and were significantly associated with walking status at 3 M (odds ratio = 0.864; 95% CI = 0.798-0.935) over and above length of stay. People post stroke who were dependent at admission and had PASS scores ≥22 were more likely to regain independence at 3 M. Nine PASS items differed among the 3 groups.

CONCLUSIONS

PASS score is significantly associated with walking status at admission and at 3 M. The identified 9 items suggest possible interventions for acute rehabilitation.

IMPACT

This study identified 9 PASS items that could guide clinicians in selecting interventions for acute rehabilitation.

Early Rehabilitation in Acute Care Inpatient Wards May Be Crucial to Functional Recovery 3 Months After Ischemic Stroke

OBJECTIVE

Early rehabilitation in acute care inpatient wards may maximize functional outcome at 3 months after stroke in survivors of stroke. It is unknown whether functional change during acute care hospitalization is significantly associated with functional recovery at 3 months in survivors of acute stroke. The purposes of this study were to examine the association of the Barthel Index (BI) at 3 months with functional change as measured with the Barthel Index (ΔBI) in an acute care inpatient ward and to identify the factors associated with ΔBI and who could benefit from an early rehabilitation program.

METHODS

In this prospective longitudinal study, 76 patients with ischemic stroke in an acute care inpatient ward received early rehabilitation of up to 2 sessions per day for 5 d/wk during their stay. Therapy density was calculated as the proportion of total therapy sessions completed. At admission and discharge, they were assessed with the BI and the Postural Assessment Scale for Stroke Patients (PASS). Demographic and health-related information was also collected. The Barthel Index (BI) was reassessed at 3 months.

RESULTS

ΔBI in the acute care inpatient ward significantly predicted the BI at 3 months, over and above the other significant variables; in addition, therapy density and change in PASS were significantly associated with ΔBI. Patients with moderate initial functional dependence had the largest ΔBI, followed by the group with a more severe condition.

CONCLUSIONS

ΔBI in acute care inpatient wards may be an important predictor of the BI at 3 months. Therapy density and change in PASS were significantly associated with ΔBI.

IMPACT

Survivors of acute stroke who receive up to 2 rehabilitation sessions per day for 5 d/wk early in their hospitalization have better functional recovery at 3 months after stroke.

Correlations between subjective rating and objective assessment of balance function in individuals with stroke

Purpose: To examine the relationships among therapist-reported, patient-reported, and objective assessment scores of balance function.Methods: Inpatients with stroke and occupational therapists were recruited. The objective balance scores were measured using the Balance Computerized Adaptive Testing (Balance CAT) system. The therapist and patient-reported scores were evaluated using a visual analogue scale (VAS) and Likert-type scale.Results: Eighty-eight patients and 16 therapists participated. The correlations (r= 0.64 and 0.65; R-squared about 0.42 at baseline and follow-up assessments, respectively) between the therapist-reported VAS scores and the Balance CAT system were larger than those (r = 0.31 and 0.21) between the patient-reported VAS scores and the Balance CAT system. Low correlations (r = 0.27 and 0.26 for VAS and Likert-type scores, respectively) were found between the therapist-reported and patient-reported change scores. Low correlations (r = 0.12-0.17) were found between the change scores of therapist- and patient-reported ratings and those of the Balance CAT system.Conclusions: The therapists' judgments explained <50% of variance of the Balance CAT system scores. Neither therapist-reported nor patient-reported change scores reflected the changes demonstrated by the objective assessments. Further studies are warranted to confirm our findings.Implications for RehabilitationNeither therapist- nor patient-reported balance function and change could effectively reflect the scores resulting from objective assessments.The routine use of objective balance assessments should not be replaced by therapists' subjective judgments.Communications regarding the balance function measured by objective assessments between therapists and patients can help patients to better understand their balance function and progress.

A Comparison of the Responsiveness of the Postural Assessment Scale for Stroke and the Berg Balance Scale in Patients With Severe Balance Deficits After Stroke

BACKGROUND AND PURPOSE

Previous evidence that the Postural Assessment Scale for Stroke (PASS) and the Berg Balance Scale (BBS) have similar responsiveness is doubtful. Compared with the BBS, the PASS has more items assessing basic balance abilities (such as postural transition during lying and sitting), so it should be more likely to detect changes in patients with severe balance deficits. We aimed to compare the responsiveness of the PASS and the BBS in patients with stroke who have severe balance deficits.

METHODS

The PASS and BBS scores of 49 patients with severe balance deficits at 14 and 30 days after stroke were retrieved. The group-level responsiveness was examined with the standardized response mean (SRM). The individual-level responsiveness was examined by the proportion of patients who achieved clinically significant improvements (ie, their pre-post change scores in the PASS/BBS exceeded the minimal detectable change with 95% confidence of each measure). The responsiveness of the 2 measures was compared using the bootstrap approach.

RESULTS AND DISCUSSION

The comparisons of responsiveness showed significant differences between the PASS and the BBS at both the group and individual levels. At the group level, the PASS indicated moderate changes in balance function (SRM = 0.79), but the BBS indicated only small changes (SRM = 0.39). At the individual level, the PASS showed that 42.9% of patients had clinically significant improvements, while the BBS showed that only 6.1% of patients had clinically significant improvements.

CONCLUSIONS

Compared with the BBS, the PASS was better able to detect balance improvements in patients having severe balance deficits. The PASS is recommended as an outcome measure to detect change in balance in patients with stroke who have severe balance deficits.

Interrater and Intrarater Reliability of the Balance Computerized Adaptive Test in Patients With Stroke

OBJECTIVE

To examine the interrater and intrarater reliability of the Balance Computerized Adaptive Test (Balance CAT) in patients with chronic stroke having a wide range of balance functions.

DESIGN

Repeated assessments design (1wk apart).

SETTING

Seven teaching hospitals.

PARTICIPANTS

A pooled sample (N=102) including 2 independent groups of outpatients (n=50 for the interrater reliability study; n=52 for the intrarater reliability study) with chronic stroke.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Balance CAT.

RESULTS

For the interrater reliability study, the values of intraclass correlation coefficient, minimal detectable change (MDC), and percentage of MDC (MDC%) for the Balance CAT were .84, 1.90, and 31.0%, respectively. For the intrarater reliability study, the values of intraclass correlation coefficient, MDC, and MDC% ranged from .89 to .91, from 1.14 to 1.26, and from 17.1% to 18.6%, respectively.

CONCLUSIONS

The Balance CAT showed sufficient intrarater reliability in patients with chronic stroke having balance functions ranging from sitting with support to independent walking. Although the Balance CAT may have good interrater reliability, we found substantial random measurement error between different raters. Accordingly, if the Balance CAT is used as an outcome measure in clinical or research settings, same raters are suggested over different time points to ensure reliable assessments.

Intrarater and Interrater Reliability of the Hierarchical Balance Short Forms in Patients With Stroke

OBJECTIVE

To examine the intrarater and interrater reliability of a quick balance measure, the Hierarchical Balance Short Forms (HBSF), in outpatients with stroke receiving rehabilitation.

DESIGN

A repeated-assessments design (1wk apart) was used to examine the intrarater and interrater reliability of the HBSF. The HBSF was administered by a single rater in the intrarater reliability study and by 2 raters in the interrater reliability study. The raters had sufficient working experience in stroke rehabilitation.

SETTING

Seven teaching hospitals.

PARTICIPANTS

Two independent groups of outpatients (N=106; each group, n=53) with stroke in chronic stages and in stable medical condition were recruited.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURE

HBSF.

RESULTS

For the intrarater reliability study, the values of the intraclass correlation coefficient (ICC), minimal detectable change (MDC), and percentage of minimal detectable change (MDC%) were .95, 1.02, and 16.3%, respectively, for the HBSF. The 95% limits of agreement (LOA) of the HBSF ranged from -.69 to 1.19. For the interrater reliability study, the values of the ICC, MDC, and MDC% were .91, 1.22, and 18.3%, respectively, for the HBSF. The 95% LOA of the HBSF ranged from -1.01 to 1.35.

CONCLUSIONS

Our results suggest that the HBSF has satisfactory intrarater and interrater reliability for assessing balance function in outpatients with stroke. The MDC values of the HBSF are useful for both researchers and clinicians to determine whether the change in balance function of an individual patient is real when administered by an individual rater or by different raters.

Psychometric properties of the Balance Computerized Adaptive Test in residents in long-term care facilities

PURPOSE

To validate the psychometric properties and efficiency of the Balance Computerized Adaptive Testing (Balance CAT) when applied to residents in long-term care (LTC) facilities.

DESIGN AND METHODS

A cohort study was conducted in central Taiwan. The Balance CAT, the Berg Balance Scale (BBS), and the Barthel Index (BI) were administered to each participant with the ability to follow simple instructions by a trained rater in two days. The Pearson's correlation coefficient (r) was used to determine the concurrent validity of the Balance CAT. ANOVA and post hoc analysis were employed to investigate the discriminative ability of the Balance CAT. The paired t test was used to validate the efficiency.

RESULTS

A total of 120 participants completed assessments of the Balance CAT, the BBS, and the Barthel Index (BI). The Pearson's r between the scores of the Balance CAT and the BBS was 0.90. Groups with different levels of dependence had significantly different mean scores of the Balance CAT. The mean IRT reliability of the Balance CAT scores was 0.93. The mean administration time of the Balance CAT was about 28% of that of the BBS, and the mean number of items used in the Balance CAT was 3.4.

CONCLUSIONS

The Balance CAT had excellent concurrent and discriminative validity, reliability, and efficiency in residents of LTC facilities. These results indicate that the Balance CAT is a sound and practical measure for assessing the balance function of residents of LTC facilities.

Reliability and responsiveness of the activities of daily living computerized adaptive testing system in patients with stroke

OBJECTIVE

To examine the intrarater reliability, interrater reliability, and responsiveness of the Activities of Daily Living Computerized Adaptive Testing system (ADL CAT) in patients with stroke.

DESIGN

One repeated-measures design (at an interval of 7d) was used to examine the intrarater reliability and interrater reliability of the ADL CAT. For the responsiveness study, participants were assessed with the ADL CAT at admission to the rehabilitation ward and at discharge from the hospital.

SETTING

Eight rehabilitation units.

PARTICIPANTS

Three different (nonoverlapping) groups of patients (N=157) were recruited. Fifty-five and 42 outpatients with chronic stroke participated in the intrarater and interrater reliability studies, respectively; 60 inpatients who had recently had a stroke participated in the responsiveness study.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURE ADL CAT RESULTS

The intraclass correlation coefficient values were .94 and .80 for the ADL CAT in the intrarater reliability and interrater reliability studies, respectively. The classical test theory-based minimal detectable change values were 6.5 and 9.5 for the ADL CAT in the intrarater reliability and interrater reliability studies, respectively. The Kazis' effect size and standardized response mean of the ADL CAT were moderate (.62-.73).

CONCLUSIONS

The ADL CAT has good intrarater reliability and interrater reliability in outpatients with chronic stroke, and sufficient responsiveness in inpatients with stroke undergoing inpatient rehabilitation. Further investigations on the responsiveness of the ADL CAT in outpatients are needed to obtain more evidence on the utility of the ADL CAT.

Comparison of the test-retest reliability of the balance computerized adaptive test and a computerized posturography instrument in patients with stroke

OBJECTIVE

To compare the test-retest reliabilities of the scores of the Balance Computerized Adaptive Test (CAT) and the Biodex Balance System in patients with stroke.

DESIGN

A repeated-measures design (at a 1-wk interval) was used to examine the test-retest reliabilities of the scores of the Balance CAT and the Biodex Balance System.

SETTING

One rehabilitation unit in a local hospital.

PARTICIPANTS

Patients (N=50) with stroke for more than 6 months and undergoing outpatient rehabilitation completed the Balance CAT and the eyes open (EO)/closed (EC) tests, but only 17 patients finished the Limit of Stability (LOS) test because they were unable to reach all the targets.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

The Balance CAT and 2 computerized tests of the Biodex Balance System, namely the EO/EC test and the LOS, were used to evaluate balance function.

RESULTS

The test-retest reliabilities of the scores of the Balance CAT (Pearson r=.92, minimal detectable change [MDC] percent=12.8%) was excellent. Those of the EO/EC and LOS tests were poor to good (Pearson r=.56-.85, MDC%=50.8%-126.9%).

CONCLUSIONS

The test-retest reliabilities of the scores of the Balance CAT were sufficient for assessing balance function in patients with stroke. Moreover, the test-retest reliabilities of the scores of the Balance CAT, one of the functional balance measures, were superior to those of the Biodex Balance System, 1 type of computerized posturography instrument. Therefore, the Balance CAT may be a more reliable measure for clinicians and researchers to use in assessing the balance function of patients with stroke for more than 6 months.

Responsiveness of a modified version of the postural assessment scale for stroke patients and longitudinal change in postural control after stroke- Postural Stroke Study in Gothenburg (POSTGOT)

Background

Responsiveness data certify that a change in a measurement output represents a real change, not a measurement error or biological variability. The objective was to evaluate the responsiveness of the modified version of the Postural Assessment Scale for Stroke Patients (SwePASS) in patients with a first event of stroke. An additional aim was to estimate the change in postural control during the first 12 months after stroke onset.

Methods

The SwePASS assessments were conducted during the first week and 3, 6 and 12 months after stroke in 90 patients. Svensson’s method, Relative Position (RP), Relative Concentration (RC) and Relative Rank Variance (RV), were used to estimate the scale’s responsiveness and the patients’ change in postural control over time.

Results

From the first week to 3 months after stroke, the patients improved in terms of postural control with 2 to 12 times larger systematic changes in Relative Position (RP), for which 9 items and the total score showed a significant responsiveness to change when compared to the intrarater reliability measurement error of the SwePASS reported in a previous study. When SwePASS was used to assess change in postural control between the first week and 3 months, 74% of the patients received higher scores while 10% received lower scores, RP 0.31 (95% CI 0.219-0.402). The corresponding figures between 3 and 6 and between 6 and 12 months were 37% and 16%, RP 0.09 (95% CI 0.030-0.152), and 18% and 26%, RP −0.07 (95% CI −0.134- (−0.010)), respectively.

Conclusions

The SwePASS is responsive to change. Postural control evaluated using the SwePASS showed an improvement during the first 6 months after stroke. The measurement property, in the form of responsiveness, shows that the SwePASS scoring method can be considered for use in rehabilitation when assessing postural control in patients after stroke, especially during the first 3 months.