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(Stroke. 1999;30:2131-2140.)
© 1999 American Heart Association, Inc.
Original Contributions |
The Stroke Impact Scale Version 2.0
Evaluation of Reliability, Validity, and Sensitivity to Change
From the Center on Aging (P.W.D., D.W., S.M.L.), and the Department of Preventative Medicine (D.W., S.M.L.), University of Kansas Medical Center, Kansas City, Kan; the Department of Veterans Affairs Medical Center, Kansas City, Mo (P.W.D., L.J.L.); the Department of Health Policy and Management (P.W.D.) University of Kansas, Overland Park, Kan; the Department of Psychology, University of Kansas, Lawrence, Kan (S.E.); and the Department of Statistics, Kansas State University (D.J.), Manhattan Kan.
Correspondence to Pamela W. Duncan, PhD, PT, Center on Aging, University of Kansas Medical Center, 3901 Rainbow Boulevard, Kansas City, KS 66160-7117. E-mail pduncan{at}kumc.edu
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Abstract |
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Background and Purpose—To be useful for clinical research, an outcome measure must be feasible to administer and have sound psychometric attributes, including reliability, validity, and sensitivity to change. This study characterizes the psychometric properties of the Stroke Impact Scale (SIS) Version 2.0.
Methods—Version 2.0 of the SIS is a self-report measure that includes 64 items and assesses 8 domains (strength, hand function, ADL/IADL, mobility, communication, emotion, memory and thinking, and participation). Subjects with mild and moderate strokes completed the SIS at 1 month (n=91), at 3 months (n=80), and at 6 months after stroke (n=69). Twenty-five subjects had a replicate administration of the SIS 1 week after the 3-month or 6-month test. We evaluated internal consistency and test-retest reliability. The validity of the SIS domains was examined by comparing the SIS to existing stroke measures and by comparing differences in SIS scores across Rankin scale levels. The mixed model procedure was used to evaluate responsiveness of the SIS domain scores to change.
Results—Each of the 8 domains met or approached the standard of
0.9 
-coefficient for comparing the same patients across time. The
intraclass correlation coefficients for test-retest reliability of SIS
domains ranged from 0.70 to 0.92, except for the emotion domain (0.57).
When the domains were compared with established outcome measures, the
correlations were moderate to strong (0.44 to 0.84). The participation
domain was most strongly associated with SF-36 social role function.
SIS domain scores discriminated across 4 Rankin levels. SIS domains are
responsive to change due to ongoing recovery. Responsiveness to change
is affected by stroke severity and time since stroke.
Conclusions—This new, stroke-specific outcome measure is reliable, valid, and sensitive to change. We are optimistic about the utility of measure. More studies are required to evaluate the SIS in larger and more heterogeneous populations and to evaluate the feasibility and validity of proxy responses for the most severely impaired patients.
Key Words: stroke • outcome • outcome assessment • reproducibility of results
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Introduction |
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TopAbstractIntroductionSubjects and MethodsResultsDiscussionReferences |
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The assessment of outcomes in individuals after stroke is important for both clinical practice and research, yet there is no consensus on the best measures of stroke outcome in either clinical practice or research.1 Existing measures have not been sensitive to change in mild strokes.2 The most commonly used outcome measures, the Rankin scale and the Barthel Index, assess only the physical aspects of stroke.3 4 No stroke-specific outcome measure has been developed that assesses other dimensions of health-related quality of life: emotion, communication, memory and thinking, and social role function. We have developed a stroke-specific outcome measure, the Stroke Impact Scale (SIS) to detect these important consequences of stroke, especially in mild to moderate strokes. The measure was developed from the perspective and input of both the patient and caregiver, and it incorporates contemporary standards of instrument development.5 Development of this outcome measure followed a comprehensive iterative process (Duncan et al, unpublished data, 1999).
The quality of any outcome measure is based on its psychometric attributes, which include reliability, validity, and sensitivity to change.8 9 10 The purpose of this article is to describe the psychometric attributes of the SIS (Version 2.0). Additionally, we assessed the relationship between the SIS scores and the patient's global assessment of percentage of recovery.
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Subjects and Methods |
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TopAbstractIntroductionSubjects and MethodsResultsDiscussionReferences |
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Stroke Impact Scale Version 2.0
The 64 items of SIS Version 2.0 comprise 8 domains (Appendix). Principal components factor analysis was performed with all 8 domains to assess the feasibility of summing scores across domains. This analysis revealed 5 factors, 1 of which encompassed 4 physical domains (including strength, hand function, mobility, and activities of daily living/instrumental activities of daily living [ADL/IADL]), with the remaining factors being emotion, communication, memory, and social participation. Therefore, if desired, the 4 physical domains can be summed to create 1 score. Emotion, communication, memory, and social participation must be scored as individual domains.
Aggregate scores in each domain were generated with an algorithm
equivalent to the scoring algorithm for the SF-36.11 For a
particular subject, if 
50% of the questions had missing responses,
the domain score was assigned as missing. Otherwise, scores for each
domain were computed using the following equation:
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The SIS also includes a question to assess the patient's global perception of percentage of recovery. After the SIS is administered, the respondent is asked to rate their percent recovery since their stroke on a visual analog scale of 0 to 100, with 0 meaning no recovery and 100 meaning full recovery (Appendix). (The SIS and the scoring algorithm can be accessed at www2.kumc.edu/coa)
Subjects
Subjects for the psychometric analysis of Version 2.0 of
the SIS were obtained from a sample of convenience, using a subset of
the participants in the Kansas City Stroke Study. The Kansas City
Stroke Study was a prospective cohort study of 459 individuals designed
to characterize the patterns of recovery of patients with mild,
moderate, and severe stroke. As described by Lai et al,12
individuals with stroke were assessed with a battery of instruments
within 14 days after stroke, and a follow-up was performed at 1, 3, and
6 months after stroke.12 Because the Kansas City Stroke
Study was in progress when the SIS was completed, only the last 105
subjects were included in the testing and analysis of the SIS
instrument. Of those subjects, 12 declined to participate and 2 of the
remaining 93 had a major stroke. Ninety-one subjects with minor and
moderate stroke were eligible to complete the SIS at 1 month.
Additionally, the SIS alone was repeated in 25 randomly selected
patients 1 week after their assessment at either 3 or 6 months, and the
data from these replicate assessments were used to assess
test-retest reliability.
Concurrent Measures for Assessment of Validity
The battery from the Kansas City Stroke Study included the
Barthel Index,4 the Functional Independence Measure
(FIM),13 the Fugl-Meyer (FM),14 the Folstein
Mini-Mental State Examination (MMSE),15 the NIH Stroke
Scale,16 the SF-36,11 the Duke Mobility
Scale,17 and the Geriatric Depression Scale
(GDS).18 Each of these measures has been established as a
tool for assessing rehabilitation outcomes, and together they provide a
battery against which to assess the concurrent validity of the SIS.
Stroke severity was determined by administration within 3 to 14 days after stroke of the Orpington Prognostic Scale,19 a weighted measure that screens for motor deficits, sensory loss, balance, and cognition. The Orpington Scale ranges for stroke severity are as follows: <3.2, minor stroke; 3.2 to 5.2, moderate stroke; and >5.2, major stroke. For the development of this instrument we included only minor and moderate strokes.
Statistical Analysis
Descriptively, we examined the mean and SD of each domain score
as a function of stroke severity. We determined floor (percentage of
subjects who scored 0) and ceiling (percentage of subjects who scored
100) effects for each domain. Item convergence and item discrimination
were assessed by computing the Pearson product moment correlation
between each item and the domain total score for each of the 8 domains.
The appropriateness of creating summative scales within each of the 8
domains was examined with the multitrait criteria described by Stewart
et al.20 21 22
To assess reliability, we evaluated the internal
consistency of each item with the Cronbach for each
domain scales23 and examined the stability of each scale
by computing the intraclass correlation coefficients (ICCs) using the
data from the 25 test-retest observations.
We examined the criterion validity of the SIS domain scores by comparing the results from the SIS to measures selected a priori from the Kansas City Stroke Study battery. For example, for the strength domain we selected a motor assessment for comparison (Fugl-Meyer Motor Assessment), for ADL/IADL domain we selected the Barthel ADL, and for memory and thinking we selected the MMSE. Criterion-related validity was assessed by examining Spearman Rank correlation coefficients. Discriminant validity was addressed by comparing mean scores for each domain to the groups defined by the Rankin scale. We used ANOVA to determine whether the SIS scores were different across Rankin classification.
To assess the sensitivity of measures to change, we used mixed model software (SAS-MIXED procedure) for repeated measures.24 Omnibus F tests were used to examine stroke severity and time main effects as well as the stroke severity*time interaction. We used t statistics within each stroke severity level to compare domain change scores for 1 to 3 months, 1 to 6 months, and 3 to 6 months. Finally, we used multiple regression analysis to determine those domain scores that most accurately predict a patient's own global assessment of the percentage of stroke recovery.
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Results |
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TopAbstractIntroductionSubjects and MethodsResultsDiscussionReferences |
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Thirty-three individuals with minor stroke and 58 moderate stroke patients participated in this study. Table 1
summarizes demographic
characteristics and the 1-month levels of the different KCSS outcome
measures for the sample. Between 1 and 3 months and between 3 and 6
months, 11 individuals were lost to follow-up SIS administration.
Reasons for loss to follow-up at 3 months included 3 deceased, 1
cognitively impaired, 1 aphasic, and 5 dropped out. Reasons for loss to
follow-up at 6 months included 2 deceased, 2 cognitively impaired, 2
moved, and 5 dropped out.
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Scale Distributions
The distribution of scores on the 8 SIS domains and the patient's
global assessment of recovery are shown in Table 2. Each of the scales showed acceptable
levels of endorsement with the full range of the scale used by these 91
subjects. For each of the scales except emotion, minor subjects on
average scored better than moderate subjects. In both minor and
moderate strokes, 3-month and 6-month scores were better than 1-month
scores. Within each of the severity groups, the SDs of the scales were
in the range of 15 to 30, signifying reasonable dispersion of outcomes
across the sample.
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Assessment of floor and ceiling effects (Table 3) showed the potential for floor effects
in the most difficult domain (hand function) in the moderate stroke
group and the possibility of a ceiling effect in the communication
domain for both the mild and moderate stroke groups. The highest
percentage of ceiling effects for the SIS was for the communication
domain (35%) compared with the 64.6% ceiling rate for the
Barthel.
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Ninety-nine item/scale correlations were used to assess the degree of
item convergence and item discrimination.20 21 22 All of the
items except 1 in the emotion domain had item domain correlations of
0.4 or greater, a level generally considered to represent
reasonable item convergence with the dimension in which it is
included.21 The item that does not have a corrected
item/domain correlation of at least 0.4 is "feel quite nervous."
Item discrimination is supported if an item's convergent correlation
is 2 SEs (2/
n) greater than correlations computed for the item and
other domains.21 The percentage of items/scale comparisons
within each domain that meet this criterion ranged from 70% to 98%.
Item discrimination is excellent for the domains of strength, emotion,
communication, and memory (89% to 98%) but only modest for ADL/IADL,
mobility, hand function, and participation domains (70% to 83%).
These domains reflect higher-level functional activity, and several
items in each domain were found to be highly correlated both with their
own domain and the other 3 domains.
Instrument Reliability
The Cronbach coefficients ranged from 0.83 to 0.90 and meet
criteria for measuring change over time.25 The ICCs of the
8 domains are in the range of 0.7 to 0.92, except for emotion
(0.57).
Instrument Validity
The discriminant validity of each SIS domain was examined by
comparison of mean scores across groups defined by the 6-month Rankin
scores. The results of the analysis (Table 4) indicate that the scales for 6 of the
8 domains were significantly different (P<0.02 to
P<0.0001) across the Rankin levels. The memory and thinking
domain and emotion domain scores are not significantly different across
the Rankin levels.
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As shown in Table 5, each of the domain
scales showed good criterion validity. The measures of disability
(mobility and ADL/IADL) showed excellent coherence with the established
measures, with correlation coefficients in the range of 0.82 to 0.84.
Correlations for domains that measure memory and communication were
more modest, generally in the range of 0.44 to 0.58. The participation
domain showed a moderate correlation with the SF-36 social function
domain (0.70), but the correlations with the SF-36 emotional and
physical role functions were low, at 0.28 and 0.45, respectively. The
correlations between the SIS domains and patient's global rating of
recovery were good (0.53 to 0.63), with weaker correlations for memory,
communication, and emotion (0.21 to 0.39).
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The multiple regression analysis of global recovery as a function of SIS domain scores revealed that physical function (P=0.0001), emotion (P=0.0002), and participation (P=0.058) domains were predictors of the patient's global assessment of recovery. Forty-five percent of the variance in the patient's assessment of percentage of recovery was explained by these factors. Basic ADL alone, as measured by the Barthel Index (P=0.0001), explained only 33% of the variance in the patient's assessment of recovery.
Sensitivity to Change
Table 6 is a summary of the SIS
domain sensitivity to change as measured by t statistics
from the mixed models. All results are stratified by severity and time
since stroke. Severity and time poststroke effect sensitivity of each
domain. For minor strokes the instrument is sensitive to change from 1
to 3 months and 1 to 6 months, but not between 3 to 6 months, for the
domains of hand function, mobility, ADL/IADL, combined physical, and
participation. For moderate strokes the instrument is also sensitive to
change to change from 1 to 3 months and 1 to 6 months, but for
higher-level functions (mobility, ADL/IADL, combined physical, and
participation) in moderate stroke the instrument is sensitive to change
from 3 to 6 months.
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Discussion |
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TopAbstractIntroductionSubjects and MethodsResultsDiscussionReferences |
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The heterogeneity of stroke severity and symptoms has created many challenges to the assessment of stroke outcomes, especially in mild and moderate stroke. The most commonly used stroke outcome measures, the Barthel Index and the Rankin scale, have captured only the physical aspects of stroke disability. Stroke impacts not only physical function but also emotion, memory and thinking, communication and role function (social participation). Focus group interviews with patients and caregivers have demonstrated that these factors should be assessed as sequelae of stroke.6 Furthermore, the results of this study have demonstrated that in addition to the physical aspects of disability, emotion and participation also predict the patient's assessment of stroke recovery. If these multiple dimensions are to be assessed in clinical trials, multiple instruments are required, and the responsiveness of these instruments in patients with varying severity has not been considered. Additionally, administration of numerous measures is burdensome to patients and researchers. Multiple domains may be captured with the SIS. Most importantly, the combined physical domain captures a wide range of skills, including hand function. No other stroke outcome measure has assessed hand function. In the development of this instrument, we have incorporated the different levels of the WHO model of disability (impairment, disability, and handicap) but have endorsed the new WHO levels of activities (for disabilities) and participation (for handicap).26 The resulting 64 items are grouped into 8 domains: strength, hand function, ADL/IADL, mobility, communication, emotion, memory, and participation. Factor analysis has revealed that strength, hand function, mobility, and ADL/IADL can be combined into a physical domain but that other domains represent distinct dimensions of recovery that should be examined individually. This combined domain has important implications for developing a summary score for outcomes in clinical trials. The individual physical domains may be retained for those who are interested in specific components of function, ie, hand function or mobility.
Existing stroke outcome measures have suffered from ceiling effects in
mild to moderate stroke.2 In 459 subjects enrolled in the
Kansas City Stroke Study, 89% with the minor strokes and 52% with
moderate strokes achieved 90 on the Barthel Index by 6 months (P.W.
Duncan, PhD, and S.M. Lai, PhD, unpublished data, 1999).
Therefore, the Barthel Index, which measures only basic ADL, has
limited ability to discriminate outcomes in most individuals who
survive stroke. The use of global measures such as the Rankin scale to
define the success of interventions may disguise meaningful shifts in
disability states and changes in health-related quality of
life.27 In contrast to the Barthel Index and the
Rankin scale, the Stroke Impact Scale (SIS) is a new measure that
broadens the range of deficits and recovery assessed, and changes in
scores may be treated continuously. Consequently, the SIS provides a
potentially more relevant outcome because stroke has variable
impact on many domains of health status. The SIS does not suffer from
the magnitude of ceiling effects observed with the Barthel Index (Table 3
). To broaden the range of ADL function, we combined basic ADL
and IADL into 1 domain. The Cronbach for this domain remains high.
The validity of combining basic and instrumental ADL into 1 scale has
also been supported by other measurement
researchers.28
The psychometric properties of the SIS Version 2.0 support its use to
measure change over time.25 The range of the Cronbach
for all domains is 0.86 to 0.90, which meets or approaches the standard
of 0.90 for comparing patients across time.25 The
test-retest reliability of 7 of the 8 instrument domains also meets the
requirements of a measure to assess the same patient across
time.9 The ICC for the emotional domain was only 0.527.
However, this ICC is substantially higher than the ICC of 0.28 reported
for the SF-36 mental health domain of stroke
patients.29
The validity of the domain constructs was supported by the analysis of convergent and divergent validity. The lowest item scaling success rates were for mobility and ADL/IADL items. The items within these domains are highly correlated across these domains and do not meet the criteria that item discrimination is supported if the item's convergent correlations is 2 SEs greater than their correlation with other domains.22 The correlation between mobility and ADL/IADL may compromise their independence as primary end points in clinical trials. However, utilization of the physical domain score (combined strength, hand function, mobility, ADL/IADL) will avoid this problem.
The discriminant validity of this measure is excellent. Domain scores for minor strokes were higher than for moderate strokes, and the scores were different across 4 Rankin levels. Three- and 6-month domain scores were higher than 1-month scores. The patterns of changes in scores, differences between 1 and 3 months, and little change between 3 and 6 months are consistent with the numerous studies that have reported that almost all stroke recovery is complete in 3 months.30 31 32 33 34 Yet most previous studies have assessed only recovery of basic ADLs and motor function. The results of this study using the SIS demonstrate that patients are changing in all dimensions except emotion and patients perceive this recovery as measured by their global assessment of percentage of recovery. The SIS change scores are congruent with the previously described patterns of recovery: most recovery occurs in the first 3 months, and recovery is determined by severity.30 31 32 33 34 35 However, in respondents with moderate stroke, the SIS detected change between 3 and 6 months for ADL/IADL, mobility, physical domain, and participation. Previous studies of recovery may not have detected this ongoing recovery due to the psychometrics of the instruments used.
In assessing the effectiveness of interventions on outcomes that progress over time, clinical researchers frequently are asked to define "clinically" meaningful change. In developing such a definition, investigators must consider the precision of the outcome measure and the magnitude of change that is physiologically relevant or has value to the patient. From these 2 perspectives, changes in SIS domain scores of approximately 10 to 15 points appear to represent reasonable definitions of clinically meaningful change. In terms of precision, the variance components analyses that formed the basis of the ICCs for the test-retest reliability indicate that the within-subject SDs on replicate tests range from 6 to 15 for the different domains. Although sample sizes were insufficient to demonstrate statistically significant differences across Rankin levels, the best estimates of mean differences between adjacent categories were 10 to 15 points for most SIS domains. Although additional testing is needed on larger samples to develop refined estimates, these initial analyses support the 10- to 15-point range as reasonable.
The emotion domain had less-desirable psychometric properties than the other domain. It has the lowest reliability, 1 item did not have acceptable item domain correlations, and it has limited sensitivity to change compared with the SF-36 mental health domain. Several reasons might explain the poor performance of this domain. First, we asked the patient to rate their emotional domain relative to the past week, while the SF-36 is in reference to the past 4 weeks. Because emotion scores are expected to exhibit more short-term variability than physical scores, the emotion domain of the SIS is likely to be somewhat less reliable than the SF-36 MHI. Also, the questions on the SIS may be related to components of emotional states that are likely to have more random variability across time, whereas the SF-36 may be capturing emotional traits. Although these results complicate analysis within the emotion domain, patient responses during the development indicate that emotion should be assessed. Furthermore, in all of our analyses, the patient's score on the emotion domain contributed significantly to the patient's perception of recovery, suggesting that at a minimum, the emotion domain must be taken into account in assessment of the effect of an intervention on outcomes in the other domains.
This study has several limitations. Most importantly, the instrument was developed on a small sample of mild and moderate stroke patients who had the communication skills and cognitive function to participate in interviews. While over two thirds of all stroke survivors have mild to moderate deficits,36 the usefulness of the SIS scale in more severely involved patients needs to be evaluated. Future studies will need to be done to develop guidelines for the minimum levels of cognitive and communication skills necessary for the patient to complete the SIS. Because individuals with major stroke will need to be included in outcome studies, we need to assess characteristics of proxy-versus-patient responses. A study assessing proxy/patient responses has been initiated. Second, this instrument was interviewer administered in the patient's home. Other modes of administration (telephone and mail questionnaire) will need to be assessed in the future. Finally, we will need to continue to develop a more stable and responsive measure of emotion.
We are optimistic about the utility of this new stroke outcome measure. However, as required in the development of any measure, an ongoing program to evaluate the measure and to explore the generalizability of the results in one sample to other stroke populations is needed.8 We have ongoing funded research programs to continue the evaluation of the Stroke Impact Scale.
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Acknowledgments |
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The present study was supported by the Department of Veterans Affairs Rehabilitation Research and Development (E8793), Glaxo-Wellcome Inc, and the University of Kansas Claude D. Pepper Older Americans Independence Center, funded by the National Institute of Aging (P60 AG 14635-02).
Received February 11, 1999; revision received July 22, 1999; accepted July 22, 1999.
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 S. L. Wolf, C. J. Winstein, J. P. Miller, S. Blanton, P. C. Clark, and D. Nichols-Larsen Looking in the Rear View Mirror When Conversing With Back Seat Drivers: The EXCITE Trial Revisited Neurorehabil Neural Repair, October 1, 2007; 21(5): 379 - 387. [Abstract] [PDF]
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K. J Sullivan Invited commentary on the movement continuum special series. Physical Therapy, July 1, 2007; 87(7): 928 - 930. [Full Text] [PDF]
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C. E. Lang and J. A. Beebe Relating Movement Control at 9 Upper Extremity Segments to Loss of Hand Function in People with Chronic Hemiparesis Neurorehabil Neural Repair, May 1, 2007; 21(3): 279 - 291. [Abstract] [PDF]
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 C. M. Boyd, C. O. Weiss, J. Halter, K. C. Han, W. B. Ershler, and L. P. Fried Framework for Evaluating Disease Severity Measures in Older Adults With Comorbidity J. Gerontol. A Biol. Sci. Med. Sci., March 1, 2007; 62(3): 286 - 295. [Abstract] [Full Text] [PDF]
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S. L Fritz, S. Z George, S. L Wolf, and K. E Light Participant Perception of Recovery as Criterion to Establish Importance of Improvement for Constraint-Induced Movement Therapy Outcome Measures: A Preliminary Study Physical Therapy, February 1, 2007; 87(2): 170 - 178. [Abstract] [Full Text] [PDF]
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 S. L. Wolf, C. J. Winstein, J. P. Miller, E. Taub, G. Uswatte, D. Morris, C. Giuliani, K. E. Light, D. Nichols-Larsen, and for the EXCITE Investigators Effect of constraint-induced movement therapy on upper extremity function 3 to 9 months after stroke: the EXCITE randomized clinical trial. JAMA, November 1, 2006; 296(17): 2095 - 2104. [Abstract] [Full Text] [PDF]
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 G. Uswatte, E. Taub, D. Morris, K. Light, and P. A. Thompson The Motor Activity Log-28: assessing daily use of the hemiparetic arm after stroke. Neurology, October 10, 2006; 67(7): 1189 - 1194. [Abstract] [Full Text] [PDF]
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E. M Frick and J. L Alberts Combined Use of Repetitive Task Practice and an Assistive Robotic Device in a Patient With Subacute Stroke Physical Therapy, October 1, 2006; 86(10): 1378 - 1386. [Abstract] [Full Text] [PDF]
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 G. Batson and J. E. Deutsch Effects of Feldenkrais Awareness Through Movement on Balance in Adults With Chronic Neurological Deficits Following Stroke: A Preliminary Study Complementary Health Practice Review, October 1, 2005; 10(3): 203 - 210. [Abstract] [PDF]
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 K Vahedi, L Benoist, A Kurtz, J Mateo, A Blanquet, M Rossignol, P Amarenco, A Yelnik, E Vicaut, D Payen, et al. Quality of life after decompressive craniectomy for malignant middle cerebral artery infarction J. Neurol. Neurosurg. Psychiatry, August 1, 2005; 76(8): 1181 - 1182. [Full Text] [PDF]
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S. L Fritz, Y.-P. Chiu, M. P Malcolm, T. S Patterson, and K. E Light Feasibility of Electromyography-Triggered Neuromuscular Stimulation as an Adjunct to Constraint-Induced Movement Therapy Physical Therapy, May 1, 2005; 85(5): 428 - 442. [Abstract] [Full Text] [PDF]
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J. V Bastille and K. M Gill-Body A Yoga-Based Exercise Program for People With Chronic Poststroke Hemiparesis Physical Therapy, January 1, 2004; 84(1): 33 - 48. [Abstract] [Full Text] [PDF]
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K. R. Crafton, A. N. Mark, and S. C. Cramer Improved understanding of cortical injury by incorporating measures of functional anatomy Brain, July 1, 2003; 126(7): 1650 - 1659. [Abstract] [Full Text] [PDF]
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R. Lindeboom, M. Vermeulen, R. Holman, and R. J. De Haan Activities of daily living instruments: Optimizing scales for neurologic assessments Neurology, March 11, 2003; 60(5): 738 - 742. [Abstract] [Full Text] [PDF]
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P.W. Duncan, S.M. Lai, R.K. Bode, S. Perera, and J. DeRosa Stroke Impact Scale-16: A brief assessment of physical function Neurology, January 28, 2003; 60(2): 291 - 296. [Abstract] [Full Text] [PDF]
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 J. M. McDowd, D. L. Filion, P. S. Pohl, L. G. Richards, and W. Stiers Attentional Abilities and Functional Outcomes Following Stroke J. Gerontol. B. Psychol. Sci. Soc. Sci., January 1, 2003; 58(1): P45 - 53. [Abstract] [Full Text] [PDF]
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 P. W. Duncan, R. D. Horner, D. M. Reker, G. P. Samsa, H. Hoenig, B. Hamilton, B. J. LaClair, T. K. Dudley, and M. Kelly-Hayes Adherence to Postacute Rehabilitation Guidelines Is Associated With Functional Recovery in Stroke * Editorial Comment Stroke, January 1, 2002; 33(1): 167 - 178. [Abstract] [Full Text] [PDF]
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L. B. Morgenstern What have we learned from clinical neuroprotective trials? Neurology, September 1, 2001; 57(90002): S45 - 47. [Abstract] [Full Text]
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R. L. Sacco, J. T. DeRosa, E. C. Haley Jr, B. Levin, P. Ordronneau, S. J. Phillips, T. Rundek, R. G. Snipes, J. L. P. Thompson, and for the GAIN Americas Investigators Glycine Antagonist in Neuroprotection for Patients With Acute Stroke: GAIN Americas: A Randomized Controlled Trial JAMA, April 4, 2001; 285(13): 1719 - 1728. [Abstract] [Full Text] [PDF]
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G. P. Samsa and D. B. Matchar Have Randomized Controlled Trials of Neuroprotective Drugs Been Underpowered? : An Illustration of Three Statistical Principles Stroke, March 1, 2001; 32(3): 669 - 674. [Abstract] [Full Text] [PDF]
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A. G. Hamedani, C. K. Wells, L. M. Brass, W. N. Kernan, C. M. Viscoli, J. N. Maraire, I. A. Awad, and R. I. Horwitz A Quality-of-Life Instrument for Young Hemorrhagic Stroke Patients Stroke, March 1, 2001; 32(3): 687 - 695. [Abstract] [Full Text] [PDF]
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G. R. Williams and J. G. Jiang Development of an Ischemic Stroke Survival Score Stroke, October 1, 2000; 31(10): 2414 - 2420. [Abstract] [Full Text] [PDF]
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D. Buck, A. Jacoby, A. Massey, and G. Ford Evaluation of Measures Used to Assess Quality of Life After Stroke Stroke, August 1, 2000; 31(8): 2004 - 2010. [Abstract] [Full Text] [PDF]
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P. W. Duncan, H. S. Jorgensen, and D. T. Wade Outcome Measures in Acute Stroke Trials : A Systematic Review and Some Recommendations to Improve Practice Stroke, June 1, 2000; 31(6): 1429 - 1438. [Abstract] [Full Text] [PDF]
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