Disability measures in stroke: relationship among the Barthel Index, the Functional Independence Measure, and the Modified Rankin Scale.

BACKGROUND AND PURPOSE: Residual disability after stroke presents a major economic and humanistic burden. To quantify disability in patients, activities of daily living (ADL; Barthel Index [BI], and motor component of Functional Independence Measure [M-FIM]) and categorical disability measures (Modified Rankin Scale [MRS]) are used. The purpose of this study is to examine the predicting ability of ADL measures to global disability scale. METHODS: Kansas City Stroke Study data were used for the present study. Correlation coefficient, Kruskal-Wallis test, and polytomous logistic regression analysis were applied to examine the relationship between the ADL measure and global disability scale. Model fit statistics were examined to verify logistic regression appropriateness. A categorization scheme, which minimized the false-positive response rate, was selected as the optimal categorizing system. RESULTS: The 3 measures were highly correlated. Both BI and M-FIM differentiated disability better in lower than higher disability. In logistic regression, BI differentiated 4 disability levels; M-FIM differentiated 3 levels in MRS. However, on the basis of results of the Kruskal-Wallis and multiple comparison tests, we suspect that M-FIM may have the potential to predict MRS categories better with a different model. CONCLUSIONS: The proposed categorization scheme can serve as a translation between measures. However, because of the ceiling effect of BI and M-FIM, the translation could not be completed for all 6 levels of MRS. No apparent variation over time in the categorization scheme was observed. Further research needs to be conducted to develop better prediction models explaining the relationship between M-FIM and MRS.

Rasch analysis of a new stroke-specific outcome scale: the Stroke Impact Scale.

OBJECTIVES: To assess multiple psychometric characteristics of a new stroke outcome measure, the Stroke Impact Scale (SIS), using Rasch analysis, and to identify and remove misfitting items from the 8 domains that comprise the SIS. DESIGN: Secondary analysis of 3-month outcomes for the Glycine Antagonist in Neuroprotection (GAIN) Americas randomized stroke trial. SETTING: A multicenter randomized trial performed in 132 centers in the United States and Canada. PARTICIPANTS: A total of 696 individuals with stroke who were community-dwelling and independent prior to acute stroke. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Rasch analysis was performed using WINSTEPS, version 3.31, to evaluate 4 psychometric characteristics of the SIS: (1) unidimensionality or fit (the extent to which items measure a single construct), (2) targeting (the extent to which the items are of appropriate difficulty for the sample), (3) item difficulty (the ordering of items from least to most difficult to perform), and (4) separation (the extent to which the items distinguish distinct levels of functioning within the sample). RESULTS: (1) Within each domain, most of the items measured a single construct. Only 3 items misfit the constructs and were deleted ("add and subtract numbers," "get up from a chair," "feel emotionally connected") and 2 items ("handle money," "manage money") misfit the combined physical domain. These items were deleted to create SIS, version 3.0. (2) Overall, the items are well targeted to the sample. The physical and participation domains have a wide range of items that capture difficulties that most individuals with stroke experience in physical and role functions, while the memory, emotion, and communication domains include items that capture limitations in the most impaired patients. (3) The order of items from less to more difficult was clinically meaningful. (4) The individual physical domains differentiated at least 3 (high, average, low) levels of functioning and the composite physical domain differentiated more than 4 levels of functioning. However, because difficulties with communication, memory, and emotion were not as frequently reported and difficulties with hand function were more frequently reported, these domains only differentiated 2 (high, low) to 3 (high, average, low) strata of patients. Time from stroke onset to administration of the SIS had little effect on item functioning. CONCLUSION: Rasch analysis further established the validity of the SIS. The domains are unidimensional, the items have an excellent range of difficulty, and the domain scores differentiated patients into multiple strata. The activities of daily living/instrumental activities of daily living, mobility, strength, composite physical, and participation domains have the most robust psychometric characteristics. The composite physical domain is most able to discriminate difficulty in function in individuals after stroke, while the communication, memory, and emotion domain items only capture limitations in function in the more impaired groups of patients.

The reliability and concurrent validity of the scoliosis research society-22 patient questionnaire for idiopathic scoliosis.

STUDY DESIGN: Outcome study to determine response distribution, internal consistency, reproducibility, and concurrent validity of the Scoliosis Research Society-22 (SRS-22) health-related quality-of-life (HRQL) questionnaire. OBJECTIVES: Further refinement of an HRQL questionnaire specific for idiopathic scoliosis. SUMMARY OF BACKGROUND DATA: Previous experience with the original and modified SRS HRQL questionnaires suggested a need for further refinement and more complete validation. METHODS: The SRS-22 and Short Form 36 (SF-36) HRQL questionnaires were mailed to 83 previously surveyed postoperative idiopathic scoliosis patients. RESULTS: Fifty-eight (70%) patients returned the first set of questionnaires. Their average age at surgery was 14.6 years, and their average follow-up interval since surgery was 10.8 years. Fifty-one (88%) of the 58 returned the second set of questionnaires an average of 28 days later. The psychometric attributes of the instruments were comparable: score distribution, SRS-22 56.9% ceiling and 1.7% floor, SF-36 79.3% ceiling and 1.7% floor; internal consistency (Cronbach alpha), SRS-22 0.92 to 0.75, SF-36 0.91 to 0.36; and reproducibility (intraclass correlation coefficient), SRS-22 0.96 to 0.85, SF-36 0.92 to 0.61. Concurrent validity, determined by Pearson Correlation Coefficients between SRS-22 and SF-36 domains, was 0.70 or greater ( < 0.0001) for 17 relevant comparisons. CONCLUSION: The SRS-22 HRQL questionnaire is reliable with internal consistency and reproducibility comparable to SF-36. In addition, it demonstrated concurrent validity when compared to SF-36. It is shorter and more focused on the health issues related to idiopathic scoliosis than SF-36.

Scoliosis research society-22 patient questionnaire: responsiveness to change associated with surgical treatment.

STUDY DESIGN: Prospective observational consecutive case series. OBJECTIVES: To determine the responsiveness to change of the Scoliosis Research Society-22 (SRS-22) patient questionnaire after surgical treatment. SUMMARY OF BACKGROUND DATA: The SRS-22 outcomes questionnaire is the outgrowth of prior research that led to modifications and improvements of the original SRS questionnaire. METHODS: Fifty-eight patients with an average age of 16 years and an average Cobb size of 63 degrees enrolled. They were tested preoperatively and at 3- (within 4 months), 6- (5-8 months), 12- (9-16 months), and 24-month (22-36 months) intervals postoperatively using the SRS-22 outcomes questionnaire. The paired Student test with multiple comparison adjustment was used to test significance of change score over time. Only patients with data on both time points of interest were included in the analysis. RESULTS: Self-image was significantly improved at 3 months ( < 0.0001) and maintained improvement through 24 months. Function was significantly decreased at 3 months ( < 0.0001), but returned to baseline by 6 months. Pain was significantly worse at 3 months ( = 0.0099), but was significantly less at 6 ( = 0.0011), 12 ( < 0.0001), and 24 ( = 0.0037) months when compared to 3 months. CONCLUSION: The SRS-22 questionnaire is responsive to changes in the postsurgical period.

Discrimination validity of the scoliosis research society-22 patient questionnaire: relationship to idiopathic scoliosis curve pattern and curve size.

STUDY DESIGN: Prospective observational study. OBJECTIVE: To determine the discriminant validity of the Scoliosis Research Society-22 (SRS-22) health-related quality-of-life (HRQL) questionnaire for idiopathic scoliosis patients based on curve pattern and curve size. SUMMARY OF BACKGROUND DATA: An important psychometric attribute of the HRQL questionnaire is the capacity to discriminate between and among patients with differing condition severity. METHOD: Three study groups, with subjects ranging in age from 10 to 16 years, were set up: a control group (C) of 19 persons with scoliosis suspected but unproven with an average age of 13 years; a nonsurgical group (NS) of 68 patients with an average age of 14 years and an average scoliosis (Cobb) of 30 degrees; and a presurgical group (PS) of 32 patients with an average age of 14 years and an average scoliosis of 61 degrees. The NS group was subdivided into untreated (NSU) (n = 54) and braced (NSB) patients (n = 14). Also created were subgroups of the NS and PS groups having similar curve sizes: nonsurgical similar (NSS) and presurgery similar (PSS). Statistical significance of the SRS-22 domain scores by comparison groups was tested by ANOVA. Relationships between the SRS-22 questionnaire and scoliosis deformity measurements were calculated using the Pearson Correlation Coefficients. RESULTS: There were no significant differences between the control (C) and nonsurgical (NS) groups. The presurgical group (PS) scored significantly lower in the pain and self-image domains than the C or NS groups and lower than group C in the mental health domain. A subgroup of the nonsurgical group (NSS) with curves comparable to the presurgical subgroup (PSS) had significantly better self-image scores. There were no significant correlations between SRS-22 scores and curve pattern. For persons with scoliosis, curve size (Cobb) correlated with pain, self-image, and function; trunk asymmetry correlated with self-image. CONCLUSION: The SRS-22 HRQL questionnaire successfully discriminated among persons with no scoliosis or moderate scoliosis and large scoliosis. It did not discriminate among patients with single, double, or triple curves. Self-image and, to a lesser extent, pain and function domain scores correlated with radiographic and trunk asymmetry severity. The SRS-22 HRQL questionnaire may be useful in choosing nonsurgical versus surgical treatment in borderline cases.