PMCC PMCC

Search tips
Search criteria

Advanced
Results 1-25 (37)
 

Clipboard (0)
None

Select a Filter Below

Journals
more »
Year of Publication
Document Types
1.  An Examination of the PROMIS® Pediatric Instruments to Assess Mobility in Children with Cerebral Palsy 
Purpose
The Patient Reported Outcomes Measurement Information System (PROMIS®) provides adult and pediatric self-report measures of health-related quality of life designed for use across medical conditions and the general population. The purpose of this study was to examine the feasibility and validity of the PROMIS® pediatric short form and computer adaptive test (CAT) mobility measures in children with cerebral palsy (CP).
Methods
Eighty-two children with CP completed self-report (PROMIS® Mobility Short Form, PROMIS® Mobility CAT, Pediatric Quality of Life Inventory™) and performance-based assessments of mobility (Timed Up-and-Go, Gross Motor Function Measure). Parents provided three proxy reports of child mobility (Pediatric Outcomes Data Collection Instrument, Functional Assessment Questionnaire, Shriners Hospitals for Children CP-CAT). Validity of PROMIS® instruments was examined through correlations with other measures and “known groups” analyses determined by Gross Motor Function Classification System (GMFCS).
Results
On average, the PROMIS® CAT required less than seven items and two minutes to administer. Both PROMIS® measures showed moderate to high correlations with child- and parent-proxy report of child mobility; correlations with performance-based measure were small for the PROMIS® Short Form and non-significant for the PROMIS® CAT. All measures except for the PROMIS® CAT were able to distinguish between GMFCS categories.
Conclusions
Results support the convergent and discriminant validity of the pediatric PROMIS® Mobility Short Form in children with CP. The PROMIS® Mobility CAT correlates well with child- and parent-report of mobility but not with performance-based measures and does not differentiate between known mobility groups.
doi:10.1007/s11136-013-0397-6
PMCID: PMC3758380  PMID: 23543391
cerebral palsy; PROMIS®; mobility; computer adaptive test; validity
2.  Designing and Implementing a System for Tracking Functional Status after Stroke: a Feasibility Study 
Objective
To determine the feasibility of tracking stroke patients’ functional outcomes in an integrated health system across a care continuum using the computer version of the Activity Measure of Post-Acute Care (AM-PAC).
Setting
A large integrated healthcare system in northern California.
Participants
222 stroke patients (aged 18 or older) hospitalized after an acute cerebrovascular accident.
Methods
An AM-PAC assessment was made at discharge from sites of care, including acute hospital, inpatient rehabilitation hospital, skilled nursing facility, home during home care, and in outpatient settings. Assessments were also completed in the patient’s home at six months. Data from the AM-PAC program was integrated with the health care system’s databases.
Main Outcome Measurements
1) AM-PAC administration time at the various sites of care; 2) assessment of a floor or a ceiling effect, 3) administrative burden of tracking participants
Results
AM-PAC assessment sessions averaged 7.9 minutes for data acquisition in 3 domains: Basic Mobility, Activities of Daily Living, and Applied Cognition. Participants answered, on average, 27 AM-PAC questions per session. A small ceiling effect was observed at 6 months and there was a larger ceiling effect when the instrument was administered in an institution, i.e., using the AM-PAC institutional item bank, rather than the community item bank. It was feasible to track patients and assess their function using the AM-PAC instrument from institutional to community settings. Implementation of the AM-PAC in clinical environments, and success of the project was influenced by instrumental, technological, operational, resource, and cultural factors.
Conclusions
This study demonstrates the feasibility of implementing a single functional outcome instrument in clinical and community settings to measure rehabilitation functional outcomes of stroke patients. Integrating the AM-PAC measurement system into clinical workflows and the electronic medical record could provide assistance to clinicians for medical decisions, functional prognostication, and discharge planning.
doi:10.1016/j.pmrj.2012.09.579
PMCID: PMC4198377  PMID: 23159241
rehabilitation; post-acute care; care continuum; stroke; cerebrovascular accident; functional outcomes measurement; AM-PAC; computer adaptive testing; electronic medical record; International Classification of Function; ICF
3.  Development of a Self-Report Physical Function Instrument for Disability Assessment: Item Pool Construction and Factor Analysis 
Objectives
To build a comprehensive item pool representing work-relevant physical functioning and to test the factor structure of the item pool. These developmental steps represent initial outcomes of a broader project to develop instruments for the assessment of function within the context of Social Security Administration (SSA) disability programs.
Design
Comprehensive literature review; gap analysis; item generation with expert panel input; stakeholder interviews; cognitive interviews; cross-sectional survey administration; and exploratory and confirmatory factor analyses to assess item pool structure.
Setting
In-person and semi-structured interviews; internet and telephone surveys.
Participants
A sample of 1,017 SSA claimants, and a normative sample of 999 adults from the US general population.
Interventions
Not Applicable.
Main Outcome Measure
Model fit statistics
Results
The final item pool consisted of 139 items. Within the claimant sample 58.7% were white; 31.8% were black; 46.6% were female; and the mean age was 49.7 years. Initial factor analyses revealed a 4-factor solution which included more items and allowed separate characterization of: 1) Changing and Maintaining Body Position, 2) Whole Body Mobility, 3) Upper Body Function and 4) Upper Extremity Fine Motor. The final 4-factor model included 91 items. Confirmatory factor analyses for the 4-factor models for the claimant and the normative samples demonstrated very good fit. Fit statistics for claimant and normative samples respectively were: Comparative Fit Index = 0.93 and 0.98; Tucker-Lewis Index = 0.92 and 0.98; Root Mean Square Error Approximation = 0.05 and 0.04.
Conclusions
The factor structure of the Physical Function item pool closely resembled the hypothesized content model. The four scales relevant to work activities offer promise for providing reliable information about claimant physical functioning relevant to work disability.
doi:10.1016/j.apmr.2013.03.011
PMCID: PMC4046327  PMID: 23542402
Disability Evaluation; Disabled Persons; Insurance; Work Disability; Questionnaires; Factor Analysis; Statistical
4.  Scale Refinement and Initial Evaluation of a Behavioral Health Function Measurement Tool for Work Disability Evaluation 
Objectives
To use item response theory (IRT) data simulations to construct and perform initial psychometric testing of a newly developed instrument, the Social Security Administration Behavioral Health Function (SSA-BH) instrument, that aims to assess behavioral health functioning relevant to the context of work.
Design
Cross-sectional survey followed by item response theory (IRT) calibration data simulations
Setting
Community
Participants
A sample of individuals applying for SSA disability benefits, claimants (N=1015), and a normative comparative sample of US adults (N=1000)
Interventions
None.
Main Outcome Measure
Social Security Administration Behavioral Health Function (SSA-BH) measurement instrument
Results
Item response theory analyses supported the unidimensionality of four SSA-BH scales: Mood and Emotions (35 items), Self-Efficacy (23 items), Social Interactions (6 items), and Behavioral Control (15 items). All SSA-BH scales demonstrated strong psychometric properties including reliability, accuracy, and breadth of coverage. High correlations of the simulated 5- or 10- item CATs with the full item bank indicated robust ability of the CAT approach to comprehensively characterize behavioral health function along four distinct dimensions.
Conclusions
Initial testing and evaluation of the SSA-BH instrument demonstrated good accuracy, reliability, and content coverage along all four scales. Behavioral function profiles of SSA claimants were generated and compared to age and sex matched norms along four scales: Mood and Emotions, Behavioral Control, Social Interactions, and Self-Efficacy. Utilizing the CAT based approach offers the ability to collect standardized, comprehensive functional information about claimants in an efficient way, which may prove useful in the context of the SSA’s work disability programs.
doi:10.1016/j.apmr.2013.03.012
PMCID: PMC4005626  PMID: 23542404
Behavioral health; Outcome assessment (healthcare); Work disability; SSA disability determination; Disability evaluation
5.  A Conceptual Foundation for Measures of Physical Function and Behavioral Health Function for Social Security Work Disability Evaluation 
Physical and mental impairments represent the two largest health condition categories for which workers receive Social Security disability benefits. Comprehensive assessment of physical and mental impairments should include aspects beyond medical conditions such as a person’s underlying capabilities as well as activity demands relevant to the context of work. The objective of this paper is to describe the initial conceptual stages of developing new measurement instruments of behavioral health and physical functioning relevant for Social Security work disability evaluation purposes. To outline a clear conceptualization of the constructs to be measured, two content models were developed using structured and informal qualitative approaches. We performed a structured literature review focusing on work disability and incorporating aspects of the International Classification of Functioning, Disability, and Health (ICF) as a unifying taxonomy for framework development. Expert interviews provided advice and consultation to enhance face validity of the resulting content models. The content model for work-related behavioral health function identifies five major domains (1) Behavior Control, (2) Basic Interactions, (3) Temperament and Personality, (4) Adaptability, and (5) Workplace Behaviors. The content model describing physical functioning includes three domains (1) Changing and Maintaining Body Position, (2) Whole Body Mobility, and (3) Carrying, Moving and Handling Objects. These content models informed subsequent measurement properties including item development, measurement scale construction, and provided conceptual coherence guiding future empirical inquiry. The proposed measurement approaches show promise to comprehensively and systematically assess physical and behavioral health functioning relevant to work.
doi:10.1016/j.apmr.2013.03.015
PMCID: PMC4010070  PMID: 23548543
Work Disability; Behavioral Health; Physical Functioning; Concept Formation; Disability Evaluation
6.  Development of an Instrument to Measure Behavioral Health Function for Work Disability: Item Pool Construction and Factor Analysis 
Objectives
To develop a broad set of claimant-reported items to assess behavioral health functioning relevant to the Social Security disability determination processes, and to evaluate the underlying structure of behavioral health functioning for use in development of a new functional assessment instrument.
Design
Cross-sectional.
Setting
Community.
Participants
Item pools of behavioral health functioning were developed, refined, and field-tested in a sample of persons applying for Social Security disability benefits (N=1015) who reported difficulties working due to mental or both mental and physical conditions.
Interventions
None.
Main Outcome Measure
Social Security Administration Behavioral Health (SSA-BH) measurement instrument
Results
Confirmatory factor analysis (CFA) specified that a 4-factor model (self-efficacy, mood and emotions, behavioral control, and social interactions) had the optimal fit with the data and was also consistent with our hypothesized conceptual framework for characterizing behavioral health functioning. When the items within each of the four scales were tested in CFA, the fit statistics indicated adequate support for characterizing behavioral health as a unidimensional construct along these four distinct scales of function.
Conclusion
This work represents a significant advance both conceptually and psychometrically in assessment methodologies for work related behavioral health. The measurement of behavioral health functioning relevant to the context of work requires the assessment of multiple dimensions of behavioral health functioning. Specifically, we identified a 4-factor model solution that represented key domains of work related behavioral health functioning. These results guided the development and scale formation of a new SSA-BH instrument.
doi:10.1016/j.apmr.2013.03.013
PMCID: PMC4010089  PMID: 23548542
Work disability; Behavioral health; Outcome assessment (health care); Psychometrics
7.  Development of a Computer-Adaptive Physical Function Instrument for Social Security Administration Disability Determination 
Objectives
To develop and test an instrument to assess physical function (PF) for Social Security Administration (SSA) disability programs, the SSA-PF. Item Response Theory (IRT) analyses were used to 1) create a calibrated item bank for each of the factors identified in prior factor analyses, 2) assess the fit of the items within each scale, 3) develop separate Computer-Adaptive Test (CAT) instruments for each scale, and 4) conduct initial psychometric testing.
Design
Cross-sectional data collection; IRT analyses; CAT simulation.
Setting
Telephone and internet survey.
Participants
Two samples: 1,017 SSA claimants, and 999 adults from the US general population.
Interventions
None.
Main Outcome Measure
Model fit statistics, correlation and reliability coefficients,
Results
IRT analyses resulted in five unidimensional SSA-PF scales: Changing & Maintaining Body Position, Whole Body Mobility, Upper Body Function, Upper Extremity Fine Motor, and Wheelchair Mobility for a total of 102 items. High CAT accuracy was demonstrated by strong correlations between simulated CAT scores and those from the full item banks. Comparing the simulated CATs to the full item banks, very little loss of reliability or precision was noted, except at the lower and upper ranges of each scale. No difference in response patterns by age or sex was noted. The distributions of claimant scores were shifted to the lower end of each scale compared to those of a sample of US adults.
Conclusions
The SSA-PF instrument contributes important new methodology for measuring the physical function of adults applying to the SSA disability programs. Initial evaluation revealed that the SSA-PF instrument achieved considerable breadth of coverage in each content domain and demonstrated noteworthy psychometric properties.
doi:10.1016/j.apmr.2013.03.021
PMCID: PMC4017369  PMID: 23578594
Disability Evaluation; Disabled Persons; Insurance; Disability; Questionnaires; Psychometrics; Models; Theoretical; Statistical; Health Status Indicators
8.  Linking the Activity Measure for Post-acute Care and the Quality of Life Outcomes in Neurological Disorders 
Objective
To use item response theory (IRT) methods to link physical functioning items in the Activity Measure for Post-acute Care (AM-PAC) and the Quality of Life Outcomes in Neurological Disorders (Neuro-QOL)
Design
Secondary data analysis of the physical functioning items of AM-PAC and Neuro-QOL. We used a non-equivalent group design with 36 core items common to both instruments. We used a test characteristic curve transformation method to for linking AM-PAC and Neuro-QOL scores. Linking was conducted so that both raw scores and scaled AM-PAC and Neuro-QOL scores (converted-logit scores with mean = 50 and SD = 10) could be compared.
Setting
AM-PAC items were administered to rehabilitation patients in post-acute care settings. Neuro-QOL items were administered to a community sample of adults via the Internet.
Participants
The AM-PAC sample consisted of 1,041 post acute care patients; the Neuro-QOL sample was 549 community-dwelling adults.
Interventions
Not applicable.
Main Outcome Measures
25 Mobility items and 11 ADL items common to both instruments were included in the analysis.
Results
Neuro-QOL items were linked to the AM-PAC scale using the Generalized Partial Credit Model. Mobility and ADL subscale scores from the two instruments were calibrated to the AM-PAC metric.
Conclusions
An IRT-based linking method placed AM-PAC and NeuroQOL Mobility and ADL scores on a common metric. This linking allowed estimation of AM-PAC Mobility and ADL subscale scores based on Neuro-QOL Mobility and ADL subscale scores, and vice versa. The accuracy of these results should be validated in a future sample in which participants respond to both instruments.
doi:10.1016/j.apmr.2011.01.026
PMCID: PMC3372982  PMID: 21958921
outcome assessment (Health Care); linking; neurological diseases; rehabilitation
9.  Does Post-Acute Care Site Matter? A longitudinal study assessing functional recovery after a stroke 
Objective
To determine the impact of post acute care site on stroke outcomes. Following a stroke, patients may receive post acute care in a number of different sites: inpatient rehabilitation (IRF), skilled nursing facility (SNF), and home health care/outpatient (HH/OP). We hypothesized that patients who received IRF would have better six-month functional outcomes than those who received care in other settings after controlling for patient characteristics.
Design
Prospective Cohort Study.
Setting
Four Northern California hospitals which are part of a single health maintenance organization.
Participants
222 patients with stroke enrolled between February 2008 and July 2010.
Intervention
Not Applicable.
Main Outcome Measure
Baseline and 6 month assessments were performed using the Activity Measure for Post Acute Care (AM-PAC™), a test of self-reported function in three domains: Basic Mobility, Daily Activities, and Applied Cognition.
Results
Of the 222 patients analyzed, 36% went home with no treatment, 22% received HH/OP care, 30% included IRF in their care trajectory, and 13% included SNF (but not IRF) in their care trajectory. At six months, after controlling for important variables such as age, functional status at acute care discharge, and total hours of rehabilitation, patients who went to an IRF had functional scores that were at least 8 points higher (twice the minimally detectable change for the AM-PAC) than those who went to a SNF in all 3 domains and in two out of three functional domains compared to those who received HH/OP care.
Conclusions
Patients with stroke may make more functional gains if their post-acute care includes an IRF. This finding may have important implications as post-acute care delivery is reshaped through health care reform.
doi:10.1016/j.apmr.2012.09.033
PMCID: PMC3584186  PMID: 23124133
stroke outcome; stroke assessment; disability evaluation; rehabilitation
10.  Adaptive Short Forms for Outpatient Rehabilitation Outcome Assessment 
Objective
To develop outpatient adaptive short forms (ASFs) for the Activity Measure for Post-Acute Care (AM-PAC) item bank for use in outpatient therapy settings.
Design
A convenience sample of 11,809 adults with spine, lower extremity, upper extremity and miscellaneous orthopedic impairments who received outpatient rehabilitation in one of 127 outpatient rehabilitation clinics in the US. We identified optimal items for use in developing outpatient ASFs based on the Basic Mobility and Daily Activities domains of the AM-PAC item bank. Patient scores were derived from the AM-PAC computerized adaptive testing (CAT) program. Items were selected for inclusion on the ASFs based on functional content, range of item coverage, measurement precision, item exposure rate, and data collection burden.
Results
Two outpatient ASFs were developed: 1) an 18-item Basic Mobility ASF and 2) a 15-item Daily Activities ASF, derived from the same item bank used to develop the AM-PAC-CAT. Both ASFs achieved acceptable psychometric properties.
Conclusions
In outpatient PAC settings where CAT outcome applications are currently not feasible, IRT-derived ASFs provide the efficient capability to monitor patients’ functional outcomes. The development of ASF functional outcome instruments linked by a common, calibrated item bank has the potential to create a bridge to outcome monitoring across PAC settings and can facilitate the eventual transformation from ASFs to CAT applications easier and more acceptable to the rehabilitation community.
doi:10.1097/PHM.0b013e318186b7ca
PMCID: PMC3947754  PMID: 18806511
Outcomes Assessment; Rehabilitation; Item Response Theory; Physical Functioning
11.  A Computer-Adaptive Disability Instrument for Lower Extremity Osteoarthritis Research Demonstrated Promising Breadth, Precision and Reliability 
Journal of Clinical Epidemiology  2009;62(8):807-815.
Objective
To develop and evaluate a prototype measure (OA-DISABILITY-CAT) for osteoarthritis research using Item Response Theory (IRT) and Computer Adaptive Test (CAT) methodologies.
Study Design and Setting
We constructed an item bank consisting of 33 activities commonly affected by lower extremity (LE) osteoarthritis. A sample of 323 adults with LE osteoarthritis reported their degree of limitation in performing everyday activities and completed the Health Assessment Questionnaire-II (HAQ-II). We used confirmatory factor analyses to assess scale unidimensionality and IRT methods to calibrate the items and examine the fit of the data. Using CAT simulation analyses, we examined the performance of OA-DISABILITY-CATs of different lengths compared to the full item bank and the HAQ-II.
Results
One distinct disability domain was identified. The 10-item OA-DISABILITY-CAT demonstrated a high degree of accuracy compared with the full item bank (r=0.99). The item bank and the HAQ-II scales covered a similar estimated scoring range. In terms of reliability, 95% of OA-DISABILITY reliability estimates were over 0.83 versus 0.60 for the HAQ-II. Except at the highest scores the 10-item OA-DISABILITY-CAT demonstrated superior precision to the HAQ-II.
Conclusion
The prototype OA-DISABILITY-CAT demonstrated promising measurement properties compared to the HAQ-II, and is recommended for use in LE osteoarthritis research.
doi:10.1016/j.jclinepi.2008.10.004
PMCID: PMC3328293  PMID: 19216052
outcome assessment (Health Care); osteoarthritis; clinical trials; disability; item response theory; computer adaptive testing
12.  Psychometric properties of the Late-Life Function and Disability Instrument: a systematic review 
BMC Geriatrics  2014;14:12.
Background
The choice of measure for use as a primary outcome in geriatric research is contingent upon the construct of interest and evidence for its psychometric properties. The Late-Life Function and Disability Instrument (LLFDI) has been widely used to assess functional limitations and disability in studies with older adults. The primary aim of this systematic review was to evaluate the current available evidence for the psychometric properties of the LLFDI.
Methods
Published studies of any design reporting results based on administration of the original version of the LLFDI in community-dwelling older adults were identified after searches of 9 electronic databases. Data related to construct validity (convergent/divergent and known-groups validity), test-retest reliability and sensitivity to change were extracted. Effect sizes were calculated for within-group changes and summarized graphically.
Results
Seventy-one studies including 17,301 older adults met inclusion criteria. Data supporting the convergent/divergent and known-groups validity for both the Function and Disability components were extracted from 30 and 18 studies, respectively. High test-retest reliability was found for the Function component, while results for the Disability component were more variable. Sensitivity to change of the LLFDI was confirmed based on findings from 25 studies. The basic lower extremity subscale and overall summary score of the Function component and limitation dimension of the Disability component were associated with the strongest relative effect sizes.
Conclusions
There is extensive evidence to support the construct validity and sensitivity to change of the LLFDI among various clinical populations of community-dwelling older adults. Further work is needed on predictive validity and values for clinically important change. Findings from this review can be used to guide the selection of the most appropriate LLFDI subscale for use an outcome measure in geriatric research and practice.
doi:10.1186/1471-2318-14-12
PMCID: PMC3909447  PMID: 24476510
Function; Disability; Psychometric properties; Community-dwelling older adults
13.  Development of the Computer-Adaptive Version of the Late-Life Function and Disability Instrument 
Background.
Having psychometrically strong disability measures that minimize response burden is important in assessing of older adults.
Methods.
Using the original 48 items from the Late-Life Function and Disability Instrument and newly developed items, a 158-item Activity Limitation and a 62-item Participation Restriction item pool were developed. The item pools were administered to a convenience sample of 520 community-dwelling adults 60 years or older. Confirmatory factor analysis and item response theory were employed to identify content structure, calibrate items, and build the computer-adaptive testings (CATs). We evaluated real-data simulations of 10-item CAT subscales. We collected data from 102 older adults to validate the 10-item CATs against the Veteran’s Short Form-36 and assessed test–retest reliability in a subsample of 57 subjects.
Results.
Confirmatory factor analysis revealed a bifactor structure, and multi-dimensional item response theory was used to calibrate an overall Activity Limitation Scale (141 items) and an overall Participation Restriction Scale (55 items). Fit statistics were acceptable (Activity Limitation: comparative fit index = 0.95, Tucker Lewis Index = 0.95, root mean square error approximation = 0.03; Participation Restriction: comparative fit index = 0.95, Tucker Lewis Index = 0.95, root mean square error approximation = 0.05). Correlation of 10-item CATs with full item banks were substantial (Activity Limitation: r = .90; Participation Restriction: r = .95). Test–retest reliability estimates were high (Activity Limitation: r = .85; Participation Restriction r = .80). Strength and pattern of correlations with Veteran’s Short Form-36 subscales were as hypothesized. Each CAT, on average, took 3.56 minutes to administer.
Conclusions.
The Late-Life Function and Disability Instrument CATs demonstrated strong reliability, validity, accuracy, and precision. The Late-Life Function and Disability Instrument CAT can achieve psychometrically sound disability assessment in older persons while reducing respondent burden. Further research is needed to assess their ability to measure change in older adults.
doi:10.1093/gerona/gls108
PMCID: PMC3670156  PMID: 22546960
Function; Disability; Computer-adaptive testing; Activity; Participation
14.  Toward a Common Language of Disablement 
doi:10.1093/gerona/glp093
PMCID: PMC2759568  PMID: 19617528
16.  An Examination of Healthy Aging Across a Conceptual Continuum: Prevalence Estimates, Demographic Patterns, and Validity 
Background.
Although the notion of healthy aging has gained wide acceptance in gerontology, measuring the phenomenon is challenging. Guided by a prominent conceptualization of healthy aging, we examined how shifting from a more to less stringent definition of healthy aging influences prevalence estimates, demographic patterns, and validity.
Methods.
Data are from adults aged 65 years and older who participated in the Health and Retirement Study. We examined four operational definitions of healthy aging. For each, we calculated prevalence estimates and examined the odds of healthy aging by age, education, gender, and race-ethnicity in 2006. We also examined the association between healthy aging and both self-rated health and death.
Results.
Across definitions, the prevalence of healthy aging ranged from 3.3% to 35.5%. For all definitions, those classified as experiencing healthy aging had lower odds of fair or poor self-rated health and death over an 8-year period. The odds of being classified as “healthy” were lower among those of advanced age, those with less education, and women than for their corresponding counterparts across all definitions.
Conclusions.
Moving across the conceptual continuum—from a more to less rigid definition of healthy aging—markedly increases the measured prevalence of healthy aging. Importantly, results suggest that all examined definitions identified a subgroup of older adults who had substantially lower odds of reporting fair or poor health and dying over an 8-year period, providing evidence of the validity of our definitions. Conceptualizations that emphasize symptomatic disease and functional health may be particularly useful for public health purposes.
doi:10.1093/gerona/glr234
PMCID: PMC3536546  PMID: 22367432
Healthy aging; Measurement; Successful aging
17.  Creating a Computer Adaptive Test Version of the Late-Life Function & Disability Instrument 
Background
This study applied Item Response Theory (IRT) and Computer Adaptive Test (CAT) methodologies to develop a prototype function and disability assessment instrument for use in aging research. Herein, we report on the development of the CAT version of the Late-Life Function & Disability instrument (Late-Life FDI) and evaluate its psychometric properties.
Methods
We employed confirmatory factor analysis, IRT methods, validation, and computer simulation analyses of data collected from 671 older adults residing in residential care facilities. We compared accuracy, precision, and sensitivity to change of scores from CAT versions of two Late-Life FDI scales with scores from the fixed-form instrument. Score estimates from the prototype CAT versus the original instrument were compared in a sample of 40 older adults.
Results
Distinct function and disability domains were identified within the Late-Life FDI item bank and used to construct two prototype CAT scales. Using retrospective data, scores from computer simulations of the prototype CAT scales were highly correlated with scores from the original instrument. The results of computer simulation, accuracy, precision, and sensitivity to change of the CATs closely approximated those of the fixed-form scales, especially for the 10- or 15-item CAT versions. In the prospective study each CAT was administered in less than 3 minutes and CAT scores were highly correlated with scores generated from the original instrument.
Conclusions
CAT scores of the Late-Life FDI were highly comparable to those obtained from the full-length instrument with a small loss in accuracy, precision, and sensitivity to change.
PMCID: PMC2718692  PMID: 19038841
outcome assessment (Health Care); geriatrics; rehabilitation
18.  Evaluation of Patient and Proxy Responses on the Activity Measure for Post Acute Care 
Background and Purpose
Our objective was to examine the agreement between adult patients with stroke and family member or clinician proxies in Activity Measure for Post Acute Care (AM-PAC) summary scores for daily activity, basic mobility, and applied cognitive function.
Methods
This study involved 67 patients with stroke admitted to a hospital within the Kaiser Permanente of Northern California system and were participants in a parent study on stroke outcomes. Each participant and proxy respondent completed the AM-PAC by personal or telephone interview at the point of hospital discharge and/or during one or more transitions to different post-acute care settings.
Results
The results suggest that for patients with a stroke proxy AM-PAC data are robust for family or clinician proxy assessment of basic mobility function, clinician proxy assessment of daily activity function, but less robust for family proxy assessment of daily activity function and for all proxy groups’ assessment of applied cognitive function. The pattern of disagreement between patient and proxy was, on average, relatively small and random. There was little evidence of systematic bias between proxy and patient reports of their functional status. The degree of concordance between patient and proxy was similar for those with moderate to severe strokes compared with mild strokes.
Conclusions
Patient and proxy ratings on the AM-PAC achieved adequate agreement for use in stroke research where using proxy respondents could reduce sample selection bias. The AM-PAC data can be implemented across institutional as well as community care settings while achieving precision and reducing respondent burden.
doi:10.1161/STROKEAHA.111.619643
PMCID: PMC3291956  PMID: 22343646
stroke outcome; stroke assessment; disability evaluation; rehabilitation
19.  Did the 1997 Balanced Budget Act Reduce Use of Physical and Occupational Therapy Services? 
Objective
To investigate whether use of physical therapy (PT) and occupational therapy (OT) services decreased after the passage of the 1997 Balanced Budget Act (BBA).
Design
Data from the nationally representative Medicare Current Beneficiary Survey (MCBS) were merged with Medicare claims data. We conducted cross-sectional analyses of data from 1995 (n=7978), 1999 (n=7863), and 2001 (n=7973). All analyses used MCBS sampling weights to provide estimates that can be generalized to the Medicare population with 5 common conditions.
Settings
Skilled nursing facilities (SNFs), home health agencies, inpatient rehabilitation facilities (IRFs), and outpatient rehabilitation settings.
Participants
Medicare beneficiaries who participated in the MCBS survey in each of the study years and had 1 or more of the following conditions: acute stroke, acute myocardial infarction, chronic obstructive pulmonary disease, arthritis or degenerative joint disease, or mobility problems.
Interventions
Not applicable.
Main Outcome Measures
Percentage of persons meeting our inclusion criteria who received PT or OT in each setting, and total units of PT and OT received in each setting.
Results
Multivariable logistic regression revealed no statistically significantly differences in the proportion of people who met our inclusion criteria who used PT or OT from home health agencies across the 3 time points. For SNFs, an increase in the odds of receiving PT was statistically significant from 1995 to 1999 (odds ratio [OR]=1.42; 95% confidence interval [CI], 1.19–1.69) and 1995 to 2001 (OR=1.69; 95% CI, 1.39–2.05). For IRF and outpatient settings, a significant increase was observed between 1995 and 2001 (OR=1.71, OR=1.27, respectively). For OT, a statistically significant increase was observed for IRF and outpatient rehabilitation settings from 1995 to 2001. For SNF, the increase was statistically significant from 1995 to 1999 and 1995 to 2001. Mean total PT and OT units received also increased across all settings from 1995 to 2001 except for IRFs.
Conclusions
Despite BBA mandates restricting postacute care expenditures, this nationally representative study showed no decreases in the percentage of Medicare beneficiaries with 5 common diagnoses receiving PT and/or OT across all settings and no decreases in units of PT and/or OT services received between 1995 and 2001 except for those in IRFs. This study suggests that the delivery of PT and OT services did not decline among persons with conditions where rehabilitation services are often clinically indicated.
doi:10.1016/j.apmr.2008.02.010
PMCID: PMC3560913  PMID: 18452725
Medicare; Occupational therapy; Physical therapy; Prospective payment system; Rehabilitation
20.  A Longitudinal Comparison of Five Preference-weighted Health State Classification Systems in Persons with Intervertebral Disc Herniation 
doi:10.1177/0272989X10380924
PMCID: PMC3535472  PMID: 21098419
Health State Preferences, Utilities, and Valuation; Health status indicators; Spine diseases; Quality of life; Economic evaluation; SPORT; Scale Validation; Cost-utility Analysis; Cost-effectiveness Analysis
21.  The contribution of osteoarthritis to functional limitations and disability 
Clinics in geriatric medicine  2010;26(3):387-399.
Synopsis
This article uses the Disablement Model conceptual framework to guide an analysis of the importance of OA in the development of disability. The Disablement Model describes the development and progression of disablement from impairments to specific functional limitations and disability, and the hypothesized role of predisposing risk factors, extra-individual factors, and intra-individual factors. A wide range of population and clinical studies have characterized the unequivocal contribution of arthritis to the development of functional limitations and disability. Evidence overwhelmingly supports a significant, moderate independent contribution of arthritis to the onset and progression of functional limitations and disability. With respect to important risk factors for the development of functional limitations and disability among those with OA, the evidence provides strong support for the role of physical impairments along with other predisposing and intra-individual factors such as age; body mass index, obesity, lack of exercise, comorbid conditions, depression; and depressive symptoms. Extra-individual factors included need for aids and assistance, and lack of access to public or private transportation. Future disablement research must clarify the causal mechanisms behind a potential risk factor’s impact on disability and delineate the interplay between and among the various hypothesized steps in the disablement process.
doi:10.1016/j.cger.2010.04.001
PMCID: PMC3529154  PMID: 20699161
osteoarthritis; arthritis; function; disability; activity; participation; disablement
22.  A Multidimensional Computer Adaptive Test Approach to Dyspnea Assessment 
Objective
To develop and test a prototype dyspnea computer adaptive test.
Design
Prospective study.
Setting
Two outpatient medical facilities.
Participants
A convenience sample of 292 adults with COPD.
Interventions
Not applicable
Main Outcome Measure
We developed a modified and expanded item bank and computer adaptive test (CAT) for the Dyspnea Management Questionnaire (DMQ), an outcome measure consisting of four dyspnea dimensions: dyspnea intensity, dyspnea anxiety, activity avoidance, and activity self-efficacy.
Results
Factor analyses supported a four-dimensional model underlying the 71 DMQ items. The DMQ item bank achieved acceptable Rasch model fit statistics, good measurement breadth with minimal floor and ceiling effects, and evidence of high internal consistency reliability (α = 0.92 to 0.98). Using CAT simulation analyses, the DMQ-CAT showed high measurement accuracy compared to the total item pool (r = .83 to .97, p < .0001) and evidence of good to excellent concurrent (r = −.61 to −0.80, p < .0001) validity. All DMQ-CAT domains showed evidence for known-groups validity (p ≤ 0.001).
Conclusions
The DMQ-CAT reliably and validly captured four distinct dyspnea domains. Multidimensional dyspnea assessment in COPD is needed to better measure the effectiveness of pharmacologic, pulmonary rehabilitation, and psychosocial interventions in not only alleviating the somatic sensation of dyspnea but also reducing dysfunctional emotions, cognitions, and behaviors associated with dyspnea, especially for anxious patients.
doi:10.1016/j.apmr.2011.05.020
PMCID: PMC3526016  PMID: 21963123
Dyspnea; COPD; Outcomes assessment; Reliability; Validity
23.  Clinical Meaningfulness of the Changes in Muscle Performance and Physical Function Associated With Testosterone Administration in Older Men With Mobility Limitation 
Context.
Testosterone in Older Men with Mobility Limitations Trial determined the effects of testosterone on muscle performance and physical function in older men with mobility limitation. Trial’s Data and Safety Monitoring Board recommended enrollment cessation due to increased frequency of adverse events in testosterone arm. The changes in muscle performance and physical function were evaluated in relation to participant’s perception of change.
Methods.
Men aged 65 years and older, with mobility limitation, total testosterone 100–350 ng/dL, or free testosterone less than 50 pg/mL, were randomized to placebo or 10 g testosterone gel daily for 6 months. Primary outcome was leg-press strength. Secondary outcomes included chest-press strength, stair-climb, 40-m walk, muscle mass, physical activity, self-reported function, and fatigue. Proportions of participants exceeding minimally important difference in study arms were compared.
Results.
Of 209 randomized participants, 165 had follow-up efficacy measures. Mean (SD) age was 74 (5.4) years and short physical performance battery score 7.7 (1.4). Testosterone arm exhibited greater improvements in leg-press strength, chest-press strength and power, and loaded stair-climb than placebo. Compared with placebo, significantly greater proportion of men receiving testosterone improved their leg-press and chest-press strengths (43% vs 18%, p = .01) and stair-climbing power (28% vs 10%, p = .03) more than minimally important difference. Increases in leg-press strength and stair-climbing power were associated with changes in testosterone levels and muscle mass. Physical activity, walking speed, self-reported function, and fatigue did not change.
Conclusions.
Testosterone administration in older men with mobility limitation was associated with patient-important improvements in muscle strength and stair-climbing power. Improvements in muscle strength and only some physical function measures should be weighed against the risk of adverse events in this population.
doi:10.1093/gerona/glr100
PMCID: PMC3202898  PMID: 21697501
Testosterone; Minimally important difference; Mobility limitation; Older men; Function promoting therapies
24.  Adverse Events Associated with Testosterone Administration 
The New England journal of medicine  2010;363(2):109-122.
Background
Testosterone supplementation has been shown to increase muscle mass and strength in healthy older men. The safety and efficacy of testosterone treatment in older men who have limitations in mobility have not been studied.
Methods
Community-dwelling men, 65 years of age or older, with limitations in mobility and a total serum testosterone level of 100 to 350 ng per deciliter (3.5 to 12.1 nmol per liter) or a free serum testosterone level of less than 50 pg per milliliter (173 pmol per liter) were randomly assigned to receive placebo gel or testosterone gel, to be applied daily for 6 months. Adverse events were categorized with the use of the Medical Dictionary for Regulatory Activities classification. The data and safety monitoring board recommended that the trial be discontinued early because there was a significantly higher rate of adverse cardiovascular events in the testosterone group than in the placebo group.
Results
A total of 209 men (mean age, 74 years) were enrolled at the time the trial was terminated. At baseline, there was a high prevalence of hypertension, diabetes, hyperlipidemia, and obesity among the participants. During the course of the study, the testosterone group had higher rates of cardiac, respiratory, and dermatologic events than did the placebo group. A total of 23 subjects in the testosterone group, as compared with 5 in the placebo group, had cardiovascular-related adverse events. The relative risk of a cardiovascular-related adverse event remained constant throughout the 6-month treatment period. As compared with the placebo group, the testosterone group had significantly greater improvements in leg-press and chest-press strength and in stair climbing while carrying a load.
Conclusions
In this population of older men with limitations in mobility and a high prevalence of chronic disease, the application of a testosterone gel was associated with an increased risk of cardiovascular adverse events. The small size of the trial and the unique population prevent broader inferences from being made about the safety of testosterone therapy.
doi:10.1056/NEJMoa1000485
PMCID: PMC3440621  PMID: 20592293
25.  Use of Physical and Occupational Therapy by Medicare Beneficiaries within Five Conditions: 1994-2001 
Objective
To examine use of physical therapy (PT) and occupational therapy (OT) among Medicare beneficiaries nationwide before and after the 1997 Balanced Budget Act (BBA), which introduced prospective payment for rehabilitation services.
Design
We analyzed responses from the longitudinal Medicare Current Beneficiary Survey, merged with Medicare claims, to track PT and OT rates and intensity (units of service) from 1994 through 2001. This observational study focused on elderly and disabled Medicare beneficiaries within five conditions: stroke, acute myocardial infarction, chronic obstructive pulmonary disease, arthritis, and lower extremity mobility problems. We used cubic smoothing spline functions to describe trends in service intensity over time and generalized estimating equations to assess changes in service intensity.
Results
Controlling for demographic characteristics, adjusted mean level of PT and OT intensity rose significantly between 1994 and 2001 for all five conditions. Service intensity leveled off in 1999 for OT and 2000 for PT. With few exceptions, PT and OT intensity was not significantly associated with patients’ demographic characteristics.
Conclusions
Medicare beneficiaries with conditions that can potentially benefit from PT and/or OT continued to get these services at similar – and sometimes increasing – intensity during years following passage of the BBA.
doi:10.1097/PHM.0b013e318198a791
PMCID: PMC3341629  PMID: 19190486
Physical Therapy; Occupational Therapy; Medicare; Prospective Payment

Results 1-25 (37)