PubMed Health⌕ Search

Biomedical subjects

P W Duncan

Publications and source records attributed to P W Duncan.

At least 19 recordsLinked to original sources
PubMed2001

Predicting stroke recovery: three- and six-month rates of patient-centered functional outcomes based on the orpington prognostic scale.

OBJECTIVE: To provide recovery rates after stroke for specific functions using the Orpington Prognostic Scale (OPS). DESIGN: Prospective cohort. SETTING: Hospital and community. PARTICIPANTS: 413 stroke survivors entered the study 3 to 14 days after suffering a stroke. MEASUREMENTS: A cohort of hospitalized stroke survivors were recruited 3 to 14 days after stroke and assessed at 1, 3, and 6 months poststroke for neurological, functional, and health status. Baseline OPS score was used to predict five functional outcomes at 3 and 6 months using development and validation datasets and receiver operating characteristic (ROC) curves. RESULTS: In 413 stroke survivors, functional recovery rates at 3 and 6 months were similar. Baseline OPS predicted significant differences in recovery rates for all five outcomes (P < .0001 for all five outcomes at 3 and 6 months). Personal care dependence was present at 3 months in only 3% of persons with baseline OPS scores of 3.2 or less compared with over 50% with OPS of 4.8 or higher. Independent personal care, meal preparation, and self-administration of medication were achieved by 80% who had baseline OPS scores of 2.4 or lower compared with less than 20% when OPS scores were 4.4 or higher. Independent community mobility was achieved in 50% of those who had OPS scores of 2.4 or lower but only 3% of those with OPS scores of 4.4 or higher. The area under ROC curves assessing OPS scores against each of the five outcomes ranged from 0.805 to 0.863 at 3 months and 0.74 to 0.806 at 6 months. CONCLUSION: OPS scores can predict widely differing rates of functional recovery in five important functional abilities. These estimates can be useful to survivors, families, providers, and healthcare systems who need to plan for the future.

Activities of Daily Living↗
PubMed2001

Stroke care: a method for measuring compliance with AHCPR guidelines.

The purpose of this article is to describe a method for converting practice guidelines to measurement criteria. To evaluate the processes of care received by patients with stroke at 11 Veteran's Administration hospital sites, we developed a measurement system based on Agency for Health Care Policy and Research (AHCPR) Post-Stroke Rehabilitation Clinical Practice Guidelines. Guideline recommendations were used as the framework for identifying important dimensions of care, and for developing chart abstraction instruments for both the acute and postacute settings. Using a modified Delphi technique to solicit opinions from an expert panel, a method was developed for aggregation of item-level chart abstraction components to overall guideline compliance scores. The measurement system was shown to have good-to-excellent intrarater and interrater reliability at the item, dimension, and overall compliance score levels. Abstraction of a sample of 100 medical records demonstrated the ability of the instruments to detect variability in processes of post-stroke care. This study provides the foundation for future research, which will evaluate associations between processes of post-stroke care, as measured by this medical chart abstraction system, and patient outcomes. (All abstraction instruments, criteria, and scoring algorithms described in this article are available for download at http://www2.kumc.edu/coa.)

Aged↗
PubMed2001

Stroke recovery profile and the Modified Rankin assessment.

BACKGROUND AND PURPOSE: The purpose of this study was to examine the relationship between the Modified Rankin Scale (MRS) and poststroke recovery in neurological deficits, activities of daily living (ADL), higher level of physical and social functioning and the patients' preference for health state. METHODS: Four hundred and fifty-nine participants in the Kansas City Stroke Study were prospectively assessed for measures of MRS, NIH Stroke Scale (NIHSS), Barthel ADL, SF-36 physical functioning, SF-36 social functioning, and Time Trade-Off (TTO). ANOVA and Bonferroni multiple comparisons were used to examine any differences in 3-month scores of NIHSS, Barthel ADL, SF-36 physical functioning, SF-36 social functioning and TTO between levels of the MRS. In addition, SF-36 physical functioning, SF-36 social functioning and TTO were characterized in patients who demonstrated improvement in global MRS outcome and also achieved a Barthel Index (BI) > or = 95 at 3 months after stroke. RESULTS: Two hundred and eighty patients (62%) shifted at least one grade in MRS from baseline to 3 months after stroke. Only 67 or 194 patients were considered to have a favorable outcome using MRS 0/1 or MRS 0/1/2, respectively, as criteria. Mean 3-month NIHSS and Barthel ADL scores were not significantly different between Rankin 0/1 and 2, but they were significantly different among Rankin 3, 4 and 5 (all p < 0.05). Mean 3-month scores of physical functioning and SF-36 social functioning were significantly different among Rankin 0/1, 2, 3 and 4 (all pairwise p < 0.05). Proportions of patients who achieved NIHSS < or = 1 or BI > or = 95 decreased as MRS grades worsened. In patients who showed improvement in MRS global outcome and also achieved BI > or = 95, mean scores on TTO were similar. CONCLUSIONS: Definition of favorable outcomes should include transition in the Modified Rankin score rather than MRS dichotomized as 0/1 or 0/1/2 because patients with transition in MRS scores have improvement in ADL, increased higher level of functioning and higher utility for health state.

Activities of Daily Living↗
PubMed2000

Defining post-stroke recovery: implications for design and interpretation of drug trials.

Measurement of stroke recovery is complex because definition of successful recovery is highly variable across measures and cut-off points for defining successful outcomes vary. The purpose of this paper is to describe patterns of recovery in stroke patients of varying severity when different measures are used and when different cut-off points are selected. 459 individuals enrolled in a prospective cohort study were assessed within 14 days post stroke and re-evaluated at 1, 3, and 6 months. Recovery was assessed using the NIH Stroke Scale, the Fugl-Meyer Assessment of Motor Recovery, the Barthel Index of Activities of Daily Living, the Physical Function Index of the SF-36, and the Modified Rankin Outcome Scale. Subjects also defined their preference (utility) for their current health state with a time-trade off question. We compared patterns of recovery using the different measures and varying the cut-off points for defining successful recovery. The percentage of patients who are believed to have recovered depends on how recovery is defined. If recovery is defined at the disability level (Barthel > 90), the majority 57.3% of stroke survivors experience a full recovery. Fewer individuals are considered to be fully recovered if impairments are measured (NIH </= 1, 44.9% and Fugl-Meyer > 90, 36.8%. Less than 25% of stroke survivors are considered recovered if recovery is defined relative to reported prior function in higher levels of physical activity. Shifting the definition of recovery on the modified Rankin scale from </= 1 to </= 2 shifts the percentage of those deemed recovered from </= 25% to 53.8%. In designing drug trials the methods for defining stroke recovery should be carefully considered. If recovery is defined in terms of disability, a higher proportion of the placebo group will achieve the outcome than if impairments are used to define recovery. The benchmarks for recovery in minor strokes must include measures of higher functioning (e.g. the SF-36 physical functioning index or a Rankin 0 (no symptoms).

Activities of Daily Living↗
PubMed2000

A taxonomy for classification of stroke rehabilitation services.

OBJECTIVE: To develop a taxonomy for use in measuring stroke rehabilitation services. DESIGN: A cross-sectional study using facility-level survey data and extant data files. SETTING: Veterans Administration medical centers (VAMCs). VARIABLES: (1) A list of rehabilitation characteristics, including personnel, physical facilities, coordination of care, and hospital characteristics; and (2) a classification or typology of VAMCs according to the type of postacute stroke care on-site. MAIN OUTCOME MEASURES: Data sources included extant Veterans Administration (VA) computerized databases, VA central office administrative files, and 2 mailed surveys to VA rehabilitation medicine services and stroke acute care services. The rehabilitation taxonomy was derived using 2 methods that assess face and construct validity, respectively: (1) an expert panel rating, using a modified Delphi process, of the clinical importance of each of the rehabilitation characteristics; and (2) a comparison of rehabilitation characteristics across the different types of VAMCs. Variables were included in the final taxonomy if the expert panel reached consensus that the variable was clinically important, or if there were statistically significant differences in these characteristics across the different types of medical centers. RESULTS: Of 67 possible rehabilitation characteristics, a multidisciplinary expert panel reached consensus about the likely clinical importance of 21 rehabilitation characteristics, 11 of which showed statistically significant differences across different types of VAMCs. An additional 9 variables that lacked expert panel consensus differed significantly among the different medical centers. These 30 variables represent a preliminary taxonomy of key rehabilitation characteristics. Among the 20 variables that varied significantly across the different types of medical centers, 18 showed a pattern with the greatest amount of resources and organizational sophistication being found in VAMCs with rehabilitation units, followed by medical centers with geriatric units, and the least amount of resources and organizational sophistication was seen in medical centers whose postacute care services were limited to nursing home or intermediate care. CONCLUSION: Thirty rehabilitation characteristics had face validity and/or construct validity, and can be considered to represent a preliminary taxonomy for measuring stroke rehabilitation services. This study also shows that there are significant differences among hospitals in resources and organization of care deemed to be important for stroke patients.

Aged↗
PubMed2000

The relation between impairments and functional outcomes poststroke.

OBJECTIVE: To assess the influence of initial stroke impairments on the severity of basic and higher level functional deficits over time and to determine the cumulative impact on functional deficits beyond severity of motor deficits alone. DESIGN: Observational study. SETTING: Twelve participating hospitals in the Greater Kansas City area, as part of the Kansas City Stroke Study (October 1995-March 1998). PARTICIPANTS: Individuals (n = 459) who sustained an eligible stroke were evaluated prospectively using standardized assessments at enrollment (within 14 days of stroke onset, 8.8 +/- 3.5 days). MAIN OUTCOME MEASURES: Mobility and activities of daily living (ADLs) were assessed at 1, 3, and 6 months poststroke using the Functional Independence Measure, Barthel index, Lawton Instrumental Activities of Daily Living (IADL), and the Medical Outcomes Study Short-Form Health Survey instruments. RESULTS: The cumulative probability of achieving independence with walking, a Barthel index of 60 or greater or 90 or greater, and independence in 3 or more IADL was significantly different for the following 4 impairment groups in descending order: motor; motor and somatosensory; motor and hemianopia; and motor, sensory, and hemianopia. Although motor severity was a strong predictor of outcome (p < .0001), the additional somatosensory and hemianopia deficits significantly (p < .05) affected time and likelihood of achieving these levels of function. CONCLUSION: Cumulative deficits poststroke affect patients' functional outcome in the first 6 months poststroke beyond the effect of motor severity alone.

Activities of Daily Living↗
PubMed2000

Outcome measures in acute stroke trials: a systematic review and some recommendations to improve practice.

BACKGROUND: There is little consistency in the measurement of outcome in acute stroke trials, and this may complicate interpretation of the results and reduce the likelihood of detecting worthwhile drug effects. This study aims to investigate empirically the measures used to date and to give recommendations for future studies. SUMMARY OF COMMENT: A systematic review of all published randomized studies of acute stroke drug intervention was undertaken, and the measures used were recorded. Fifty-one studies involving 57 214 subjects were identified. These studies used 14 different measures of impairment, 11 different measures of activity, 1 measure of "quality of life," and 8 miscellaneous other measures. Timing of outcome assessments varied from 1 week to 1 year, with the modal time being 3 months. Many studies used ordinal measures but dichotomized results for analysis. Of the 51 studies included in the review, only 21 demonstrated benefit with the defined primary outcome measure. In several studies, however, post hoc analysis using varied outcome measures or varied cut points for dichotomizing outcomes resulted in positive results, whereas the primary study analysis failed to do so. CONCLUSIONS: There is no consensus on the level of outcome to be used, the method of measurement to be used, or the most appropriate timing of the assessment. It is recommended that future studies should include extended/instrumental activities and advanced mobility as components of the primary outcome measure, with outcome assessment being undertaken at 6 months. New initiatives in developing stroke-specific outcomes may address some of the current problems in the assessment of stroke outcomes

Activities of Daily Living↗
PubMed2000

Upper extremity control in adults post stroke with mild residual impairment.

Motor control deficits in the upper extremity (UE) ipsilateral to the side of brain damage persist after stroke, but it is not known if the presence of these deficits is related to impairment of the contralateral UE. The purpose of this study was to investigate whether motor deficits are present in the ipsilateral UE when contralateral UE impairment is mild in adults with chronic stroke. Right-handed adults (10 controls, 10 right stroke, 10 left stroke) performed rapid continuous aiming movements to small and large targets. Using kinematic analysis, temporal measures of the movement were defined, including movement time (MT) and the three components of MT: acceleration, deceleration, and dwell time (i.e., time on target). Participants with right stroke had prolonged MT only with the left UE, primarily due to longer dwell times. Participants with left stroke had prolonged MT with both UEs as a result of longer dwell times. The results indicate that control deficits of the ipsilateral UE are evident in individuals with left but not right brain damage who have minimal impairment of the contralateral UE. These findings are consistent with the role of the left hemisphere in the control of both UEs.

Aged↗
PubMed2000

Reliability of lower extremity isokinetic strength testing in adults with stroke.

OBJECTIVE: To evaluate the reliability of isokinetic strength testing of knee flexion and extension at 60 degrees per second, and ankle plantar flexion and dorsiflexion at 30 degrees per second in adults with stroke. DESIGN: Test-retest using intraclass correlation coefficients (ICC). SETTING: Human performance laboratory. SUBJECTS: Ten adults post stroke with a mean age of 64 years (five males) and 10 adults without neurological injury with a mean age of 69 years (three males) who served as controls. MAIN OUTCOME MEASURES: Peak torque and average torque. RESULTS: The reliability of strength of the less-affected lower extremity was high with values ranging from 0.75 to 0.97. Knee extension, ankle plantar flexion and the peak torque of dorsiflexion were reliable for the affected limb, ranging from 0.80 to 0.90. In contrast, affected knee flexion was not reliable with values of 0.48 and 0.44 for peak torque and average peak torque respectively. CONCLUSIONS: Isokinetic knee and ankle strength of the less-affected limb are reliable. Isokinetic strength of the affected lower extremity is also reliable with the noted exception of knee flexion.

Aged↗
PubMed1999

Reliability of physical performance tests in four different randomized clinical trials.

OBJECTIVES: (1) To assess the test-retest reliability of physical performance tests in subject groups with different levels of impairment and disability, and (2) to assess the stability of these tests over different time intervals. DESIGN: Test-retest, repeated measures reliability design. SETTING: (1) A university's center for aging and research center, (2) a continuing care retirement community, and (3) an extended care and rehabilitation center at a Veterans Affairs medical center. SUBJECTS: Twenty-four community-dwelling elders, 15 community-dwelling elders with Parkinson disease, 12 older women with vertebral osteoporosis and compression fractures, and 14 elderly nursing home residents. MEASURES: Lower extremity isometric strength (ankle dorsiflexion, hip abduction), spinal configuration (thoracic kyphosis, lumbar lordosis), lumbosacral motion (flexion, extension), and timed measures of the ability to get in and to get out of bed at a usual pace. RESULTS: Most of the within-group intraclass correlation coefficients (ICCs) were good to excellent (.70 to .97). Overall, ICCs for all groups combined were between .70 and .96, and no decrement in reliability was noted after controlling for group membership. In addition, no decrement in the ICC was observed for short (1 day) vs. longer (1 week) intervals of testing. CONCLUSIONS: These performance-based measures may be used reliably across a wider range of testing environments and elderly populations than has been reported.

Ankle Joint↗
PubMed1999

The stroke impact scale version 2.0. Evaluation of reliability, validity, and sensitivity to change.

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 alpha-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.

Aged↗
PubMed1999

Evaluation of the American Heart Association Stroke Outcome Classification.

BACKGROUND AND PURPOSE: The purpose of this study was to evaluate the concurrent validity of the American Heart Association Stroke Outcome Classification (AHA.SOC) and compare performance of its function classification with that of the Modified Rankin Scale. METHODS: The individuals in this study included the last 105 consecutive subjects who were part of a cohort of 459 stroke patients in the Kansas City Stroke Study. The patients were evaluated with a variety of standardized assessments at enrollment (within 14 days of stroke onset) and followed at 1, 3, and 6 months after stroke. Specifically, we examined validity of AHA.SOC by comparing its 3 domains (ie, Domain, Severe, and Function) with stroke severity. We correlated AHA.SOC-Function with scores of the Barthel Index, Lawton Instrumental Activities of Daily Living (IADL) Scale, and Medical Outcome Study 36-Item Short-Form Health Survey (SF-36) measures of physical function and mental health. Finally, we compared the discriminant ability of AHA.SOC-Function and the Modified Rankin Scale in assessing disability and handicap. These data were analyzed with the use of Spearman rank correlations and Kruskal-Wallis tests. RESULTS: All 3 domains of the AHA.SOC were significantly associated with stroke severity and scores of Barthel Index, Lawton IADL, and SF-36 physical function (all P<0.001). Both AHA.SOC-Function and the Modified Rankin Scale discriminated well the disabilities and handicap measured by Barthel Index, Lawton IADL, and SF-36 physical function (all P<0.001). CONCLUSIONS: The AHA.SOC was able to capture impairments, disabilities, and handicap after stroke. The AHA. SOC-Function performed equally as well as the Modified Rankin Scale in assessing disabilities related to basic activities of daily living but differentiated slightly better than the Modified Rankin Scale in assessing disabilities/handicap related to instrumental activities of daily living. Neither the AHA.SOC-Function nor the Modified Rankin Scale captured differences in mental health after stroke.

Aged↗
PubMed1999

Development of a comprehensive assessment toolbox for stroke.

Comprehensive databases for the assessment of individuals with stroke are essential for clinical management and evaluation of outcomes for quality management and research. The purpose of this article is to describe a comprehensive data system or "toolbox" developed by clinicians and researchers at the Center on Aging at the University of Kansas Medical Center. The choice of assessments for the toolbox resulted from the Agency for Health Care Policy and Research Post-Stroke Rehabilitation Guidelines, results of the Kansas City Stroke Study, and the authors' work to develop a new stroke measure-the Stroke Impact Scale.

Aged↗
PubMed1999

New horizons in stroke rehabilitation research.

To promote health services research in stroke rehabilitation, we gathered information about stroke rehabilitation structures, processes, and outcomes (SPO), using extant databases and the Donabedian theoretical model of health services evaluation. We found that, in the United States, over S3.6 billion was spent by third-party payers in 1992 on rehabilitation, including stroke. Total disability-related costs now amount to over $170 billion per year. However, there are few studies identifying cost-effective stroke rehabilitation practices. Existing studies indicate that the organizational structure of rehabilitation influences stroke outcomes, but it is less clear exactly what organizational practices constitute optimal stroke rehabilitation. Data about specific, beneficial rehabilitation processes are scanty for stroke. There are a number of valid and reliable outcome measures pertinent to stroke rehabilitation health services research. We conclude that health services research in stroke rehabilitation is sparse. To be more informative, rehabilitation health services research should be guided by the SPO model.

Cost-Benefit Analysis↗
PubMed1998

Utilities for major stroke: results from a survey of preferences among persons at increased risk for stroke.

BACKGROUND: Patient beliefs, values, and preferences are crucial to decisions involving health care. In a large sample of persons at increased risk for stroke, we examined attitudes toward hypothetical major stroke. METHODS AND RESULTS: Respondents were obtained from the Academic Medical Center Consortium (n = 621), the Cardiovascular Health Study (n = 321 ), and United Health Care (n = 319). Preferences were primarily assessed by using the time trade off (TTO). Although major stroke is generally considered an undesirable event (mean TTO = 0.30), responses were varied: although 45% of respondents considered major stroke to be a worse outcome than death, 15% were willing to trade off little or no survival to avoid a major stroke. CONCLUSIONS: Providers should speak directly with patients about beliefs, values, and preferences. Stroke-related interventions, even those with a high price or less than dramatic clinical benefits, are likely to be cost-effective if they prevent an outcome (major stroke) that is so undesirable.

Adult↗
PubMed1998

Is lower extremity strength gain associated with improvement in physical performance and disability in frail, community-dwelling elders?

BACKGROUND: Strength loss is strongly associated with functional decline and is reversible with exercise. The effect of increased strength on function has not been clearly established. The purpose of this study was to determine whether strength gain is associated with improvement in physical performance and disability. METHODS: One hundred functionally impaired community-dwelling men and women (77.6 +/- 7.6 yrs) were tested at baseline and outcome for lower extremity strength, physical performance, and disability. After random group assignment, exercise participants received strengthening exercises in their homes three times a week for 10 weeks while control subjects continued their normal activities. Using multiple regression techniques, the relationship between strength gain and improvement in physical performance and disability was assessed, controlling for age, depression, and baseline strength. RESULTS: A significant impact of strength gain on mobility skills (p = .0009) was found. The impact of strength gain on chair rise performance was significant in participants who were more impaired (p = .04). Strength gain was associated with gain in gait speed (p = .02) and in falls efficacy (p = .05), but not with other balance, endurance, or disability measures. CONCLUSIONS: Lower extremity strength gain is associated with gains in chair rise performance, gait speed, and in mobility tasks such as gait, transfers, stooping, and stair climbing, but not with improved endurance, balance, or disability. Strength gain is also associated with improvement in confidence in mobility. Factors that may influence the ability of strength gain to affect function are initial level of frailty and specificity of exercise. These results support the idea that strength training is an intervention that can potentially improve physical health status in many frail elders.

Activities of Daily Living↗