Measuring disability in Medicare home care patients: application of Rasch modeling to the outcome and assessment information set

Using the Outcome and Assessment Information Set to Measure Patient Health Status in Research: A Systematic Review

OBJECTIVES

To review, evaluate, and synthesize existing literature on how health status changes were measured using the Outcome and Assessment Information Set (OASIS).

DESIGN

Systematic review.

SETTING AND PARTICIPANTS

Studies were included if they examined the health status of adult patients at 2 or more time points using OASIS, which is a comprehensive assessment tool mandated for home health (HH) patients.

METHODS

A systematic search was conducted in PubMed, CINAHL, Embase, and Scopus. The methodological quality of the included studies was appraised using the National Institutes of Health quality assessment tool.

RESULTS

The initial search yielded 1587 citations, resulting in 27 eligible studies published between 2005 and 2022. All included studies were retrospective cohort studies, with overall quality ranging from good to fair. These studies primarily targeted patients with heart failure, with sample sizes between 40 and 6,637,497 and mean ages of 61.2 to 82.4 years. OASIS version C was the most used version, comparing health status at admission and discharge. Patient health status outcomes encompassed functional (n = 24), physiological (n = 6), emotional/behavioral (n = 4), and cognitive (n = 2) outcomes. Various techniques were employed for scale standardization, compositing individual scores, measuring changes, and reporting outcomes. The predominant methods for assessing change included the corrected Likert scale for standardization, composite change scores for change calculation, and continuous outcomes for reporting.

CONCLUSION AND IMPLICATIONS

Researchers have used OASIS to assess patient health status changes in functional, physiological, emotional/behavioral, and cognitive outcomes during the HH episode. Variations in OASIS items and assessment methods across studies have been observed. Our findings underscore the need to standardize item application in research, enabling researchers to synthesize evidence effectively and enhance understanding of patient recovery and HH services. For policymakers and health care providers, these insights could inform resource allocation, care planning, and tailored interventions, ultimately improving health care quality and efficiency.

Risk factors for inpatient facility admission among home health care patients with diabetes

BACKGROUND

Home health care (HHC) patients with diabetes are at high risk for inpatient admissions.

PURPOSE

To identify variables associated with inpatient admissions among adults age ≥50 with diabetes receiving HHC in the community and in assisted living (AL).

METHODS

Retrospective HHC data (collected October 2021 to March 2022 in the Southern United States) from the Outcome and Assessment Information Set D were analyzed with logistic regression (n = 5,308 patients).

DISCUSSION

The inpatient admission rate was 29.5%. For community-dwelling patients, multiple hospitalizations, depression, limited cognitive function, decreased activities of daily living (ADL) performance, and unhealed pressure ulcer or injury ≥stage 2 were significantly associated with inpatient admission. For those in AL, multiple prior hospitalizations and decreased ability to perform ADLs were associated with inpatient admission.

CONCLUSION

Understanding risk factors for inpatient admissions among patients with diabetes can support the identification of at-risk patients and inform interventions.

Dimensionality and invariance of ADL, IADL, BI-M2/WG-SS, and GALI in large surveys in France (2008-2014) and implications for measuring disability in epidemiology

BACKGROUND

The epidemiological investigation and surveillance of disability requires well-constructed, invariant, and, if possible, exchangeable measures. However, the current or recommended measures have not been thoroughly investigated with respect to these issues. Here we examined the dimensional structure and invariance of four measures across sociodemographic groups: Activities of Daily Living (ADL), Instrumental Activities of Daily Living (IADL), Budapest Initiative Mark 2 (BI-M2) and Washington Group on Disability Statistics Short Set (WG-SS), and Global Activity Limitation Indicator (GALI).

METHODS

We used data from three large nationwide representative surveys conducted in France between 2008 and 2014. The surveys included these four measures and classical and modern approaches (correlations, principal component analysis, Rasch modeling) were used to assess their dimensional structure as well as their invariance through differential item functioning (DIF) for sociodemographic characteristics. Polytomous logistic regression models were used to assess gradients in health inequalities associated with these measures.

RESULTS

For many items of ADL, IADL, and BI-M2/WG-SS, we consistently observed disordered response thresholds, rejection of unidimensionality, and DIF evidence for sociodemographic characteristics across the survey samples. Health inequality gradients were erratic. In addition, it was impossible to identify a common continuum for GALI, ADL, IADL, and BI-M2/WG-SS or their constituent items.

CONCLUSION

This study warns against the current practice of investigating disability in epidemiology using measures that are unsuitable for epidemiological use, incommensurable, and inadequate regarding the basic requisites of dimensionality and invariance. Developing invariant measures and equating them along a common continuum to enlarge the common bases of measurement should therefore be a priority.

Association of Cognitive Impairment With Rate of Functional Gain Among Older Adults With Stroke

OBJECTIVES

This study explored the association between cognitive impairment at admission with self-care and mobility gain rate (amount of change per week) during a post-acute care stay (admission to discharge) for older adults with stroke.

DESIGN

Retrospective cohort study.

SETTING AND PARTICIPANTS

Four inpatient rehabilitation and 6 skilled nursing facilities. A total of 100 adults with primary diagnosis of stroke; mean age 79 years (SD 7.7); 67% women.

METHODS

Retrospective cohort study. We evaluated the extent to which cognitive impairment at admission explained variation in weekly gain rate separately for self-care and mobility. Additional covariates were occupational and physical therapy minutes per day, self-care and mobility function at admission, age, and number of comorbidities.

RESULTS

Participants were classified as having severe (n = 16), moderate (n = 39), or mild (n = 45) cognitive impairment at admission. Occupational therapy minutes per day (β = 0.04; P < .01) and Functional Independence Measure (FIM) self-care function at admission (β = 0.48; P < .01) were both significantly associated with self-care gain rate (Adjusted R² = 0.18); cognitive impairment group, age, and number of comorbidities were not significant. Only FIM mobility function at admission (β = 0.29; P < .001) was significantly associated with mobility gain rate (Adjusted R² = 0.18); cognitive impairment group, physical therapy minutes, age, and number of comorbidities were not significant.

CONCLUSIONS AND IMPLICATIONS

These results provide preliminary evidence that patients with stroke who have severe cognitive impairment may benefit from intensive therapy services as well as less severely impaired patients, particularly occupational therapy for improvement in self-care function.

Care-Partner Support and Hospitalization in Assisted Living During Transitional Home Health Care

BACKGROUND/OBJECTIVES

Care-partner support affects outcomes among assisted living (AL) residents. Yet, little is known about care-partner support and its effects on hospitalization during post-acute care transitions. This study examined the variation in care-partner support and its impact on hospitalizations among AL residents receiving Medicare home health (HH) services.

DESIGN

Analysis of national data from the Outcome and Assessment Information Set, Medicare claims, Area Health Resources File, and the Social Deprivation Index File.

SETTING

AL facilities and Medicare HH agencies in the United States.

PARTICIPANTS

741,926 Medicare HH admissions of AL residents in 2017.

MEASUREMENTS

Care-partner support during the HH admission was measured based on the type and frequency of assistance from AL staff in seven domains (i.e., activities of daily living (ADL), instrumental ADLs, medication administration, treatment, medical equipment, home safety, and transportation). Care-partner support in each domain was measured as "assistance not needed" (reference group), "Care-partner currently provides assistance," "care-partner need additional training/support to provide assistance" (i.e., inadequate care-partner support), and "care-partner unavailable/unlikely to provide assistance" (i.e., unavailable care-partner support). Outcome was time-to-hospitalization during the HH admission.

RESULTS

Among the 741,926 Medicare HH admissions of AL residents, inadequate care-partner support was identified for all seven domains that ranged from 13.1% (for transportation) to 49.8% (for treatment), and care-partner support was unavailable from 0.9% (for transportation) to 11.0% (for treatment). In Cox proportional hazard models adjusted for patient covariates and geography, compared with "assistance not needed", having inadequate and unavailable care-partner support was related to increased risk of hospitalization by 8.9% (treatment (hazard ratio (HR) =1.089, P < .001)) to 41.3% (medication administration (HR =1.413, P < .001)).

CONCLUSION

For AL residents receiving HH services, having less care-partner support was related to increased risk of hospitalization, particularly regarding medication administration, medical equipment, and transportation/advocacy.

Utilization and Functional Outcomes Among Medicare Home Health Recipients Varied Across Living Situations

BACKGROUND/OBJECTIVES

Home health (HH) is a major type of home-based skilled care available to Medicare beneficiaries. We examined the association between living situation (home alone, home with others, and assisted living (AL) residence) and utilization and functional outcomes among Medicare HH recipients.

DESIGN

Analysis of national data from the Outcome and Assessment Information Set, HH Compare, Medicare claims, and Area Health Resource Files.

SETTING

Medicare-certified HH agencies in the United States.

PARTICIPANTS

National population of Medicare beneficiaries ≥65 years old who received HH care in CY 2017 (N = 6,637,496).

MEASUREMENTS

Outcomes included time-to-event measures of hospitalization and emergency department (ED) visits, and improvement in activities of daily living (ADL) from the start to the end of the HH admission.

RESULTS

AL residents (12%) and patients living alone at home (24%) had longer survival time without hospitalization and ED visits than patients living with others at home (64%). Adjusting for covariates and HH agency-level random effects, and compared with patients living with others, AL residents had lower risk of hospitalization (hazard ratio (HR) = 0.85, P < .001) and ED visit (HR = 0.92, P < .001); however, less ADL improvement (β = 0.29 (29% less of total independence in one ADL)); and patients living alone had lower risk of hospitalization (HR = 0.94, P < .001) and ED visit (HR = 0.93, P < .001), yet more ADL improvement (β = -0.15 (15% more of total independence in one ADL)).

CONCLUSION

In the national population of Medicare HH recipients, patients living with others at home had the highest risk of hospitalization and ED visits, whereas AL residents had the lowest risk of hospitalization and patients living alone at home had the lowest risk of ED visits, meaning that combined support from HH and AL reduces acute care admissions. Evidence-based interventions are needed for HH patients living with others at home to avoid unnecessary acute care use.

Assessing functional status using the IADL-extended scale: results from the HELIAD study

OBJECTIVES

Instrumental activities of daily living (IADL) have been operationalized as exhibiting a greater level of complexity than basic ADL. In the same way, incorporating more advanced ADLs may increase the sensitivity of functional measures to identify cognitive changes that may precede IADL impairment. Towards this direction, the IADL-extended scale (IADL-x) consists of four IADL tasks and five advanced ADLs (leisure time activities).

DESIGN

Retrospective, cross-sectional study.

SETTING

Athens and Larissa, Greece.

PARTICIPANTS

1,864 community-dwelling men and women aged over 64.

MEASUREMENTS

We employed both the IADL-x and IADL scales to assess functional status among all the participants. Diagnoses were assigned dividing the population of our study into three groups: cognitively normal (CN), mild cognitive impairment (MCI) and dementia patients. Neuropsychological evaluation was stratified in five cognitive domains: memory, language, attention-speed, executive functioning and visuospatial perception. Z scores for each cognitive domain as well as a composite z score were constructed. Models were controlled for age, sex, education and depression.

RESULTS

In both IADL-x and IADL scales dementia patients reported the most functional difficulties and CN participants the fewest, with MCI placed in between. When we restricted the analyses to the CN population, lower IADL-x score was associated with worse cognitive performance. This association was not observed when using the original IADL scale.

CONCLUSION

There is strong evidence that the endorsement of more advanced IADLs in functional scales may be useful in detecting cognitive differences within the normal spectrum.

Combining Items From 3 Federally Mandated Assessments Using Rasch Measurement to Reliably Measure Cognition Across Postacute Care Settings

OBJECTIVE

To combine items from the Functional Independence Measure, Minimum Data Set (MDS) 2.0, and the Outcome and Assessment Information Set (OASIS)-B to reliably measure cognition across postacute care settings and facilitate future studies of patient cognitive recovery.

DESIGN

Rasch analysis of data from a prospective, observational cohort study.

SETTING

Postacute care inclusive of inpatient rehabilitation facilities, skilled nursing facilities, and home health agencies.

PARTICIPANTS

Patients (N=147) receiving rehabilitation services.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Functional Independence Measure, MDS 2.0, and the OASIS-B.

RESULTS

Six cognition items demonstrated good construct validity with no misfitting items, unidimensionality, good precision (person separation reliability, 0.95), and an item hierarchy that reflected a clinically meaningful continuum of cognitive challenge.

CONCLUSIONS

This is the first attempt to combine the cognition items from the 3 historically, federally mandated assessments to create a common metric for cognition. These 6 items could be adopted as standardized patient assessment data elements to improve cognitive assessment across postacute care settings.

Older Adult Attendance in Cardiac Rehabilitation: IMPACT OF FUNCTIONAL STATUS AND POSTACUTE CARE AFTER ACUTE MYOCARDIAL INFARCTION IN 63 092 MEDICARE BENEFICIARIES

PURPOSE

Older adults who use postacute care (PAC) after hospitalization for myocardial infarction (MI) are often overlooked as cardiac rehabilitation (CR) candidates because of physical limitations. This research describes the impact of functional status and PAC, including inpatient rehabilitation facility (IRF), skilled nursing facility (SNF), or home health care (HHC), on CR initiation in Medicare beneficiaries discharged from the hospital following an index MI.

METHODS

The Chronic Condition Warehouse database of Medicare beneficiaries discharged to PAC following index MI in 2008 (n = 63 092) was used for this retrospective study. Functional status at PAC discharge was described as dependent, needed assistance, needed supervision, or independent. Logistic regression examined factors associated with CR initiation.

RESULTS

CR was initiated by 3% and 21% of beneficiaries discharged from PAC as dependent or independent, respectively. Beneficiaries who were dependent, needed assistance, or needed supervision were 78% (95% CI, 0.18-0.28), 60% (0.32-0.49), and 51% (0.41-0.57) less likely to initiate CR compared with independent beneficiaries. Those who had used IRF were 40% more likely to initiate CR compared with those who had used HHC, with no difference observed between those who had used SNF compared with HHC.

CONCLUSIONS

Functional status at PAC discharge was strongly associated with CR initiation. Beneficiary initiation of CR was at proportions corresponding to the level of independence. Beneficiaries discharged from PAC as independent initiated CR at rates slightly higher than non-PAC users, and those discharged from IRF were more likely to initiate CR. These findings are promising and more targeted recruitment from PAC may increase CR initiation and completion, resulting in continued improvement in functional status.

Home-Health-Care Physical Therapy Improves Early Functional Recovery of Medicare Beneficiaries After Total Knee Arthroplasty

BACKGROUND

Home-health-care utilization after total knee arthroplasty (TKA) is increasing. Recent publications have suggested that supervised rehabilitation is not needed to optimize functional recovery after TKA; however, few studies have evaluated patients in home-health-care settings. The objectives of this study were to (1) determine whether physical therapy (PT) utilization is associated with functional improvements for patients in home-health-care settings after TKA and (2) determine which factors are related to utilization of PT.

METHODS

This study was an analysis of Medicare home-health-care claims data for patients treated with a TKA in 2012 who received home-health-care services for postoperative rehabilitation. Multivariable linear regression models were used to evaluate relationships between PT utilization and recovery in activities of daily living (ADLs). Negative binomial regression models were used to determine factors associated with PT utilization.

RESULTS

Records from 5,967 Medicare beneficiaries were evaluated. Low home-health-care PT utilization (≤5 visits) was associated with less improvement in ADLs compared with 6 to 9 visits, 10 to 13 visits, or ≥14 visits. Compared with low home-health-care utilization, utilization of 6 to 9 visits was associated with a 25% greater improvement in ADLs over the home-health-care episode (p < 0.0001); 10 to 13 visits, with a 40% greater improvement (p < 0.0001); and ≥14 visits, with a 50% greater improvement (p < 0.0001). The findings remained robust following adjustments for medical complexity, baseline functional status, and home-health-care episode duration. After adjustment, lower PT utilization was observed for patients receiving home health care from rural agencies (10.7% fewer visits, 95% confidence interval [CI] = 7.9% to 13.7%), those with depressive symptoms (4.8% fewer visits, 95% CI = 1.3% to 8.3%), and those with any baseline dyspnea (5.3% fewer visits, 95% CI = 3.1% to 7.5%).

CONCLUSIONS

Low home-health-care PT utilization was significantly associated with worse recovery in ADLs after TKA for Medicare beneficiaries, after controlling for medical complexity, baseline function, and home-health-care episode duration. Patients who are served by rural agencies or who have higher medical complexity receive fewer PT visits after TKA and may need closer monitoring to ensure optimal functional recovery.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Effect of home-based rehabilitation on activities of daily living and gait in older adults with heart failure at risk for falling: A retrospective cohort study

PURPOSE

The purpose of this study is to describe improvement in activities of daily living (ADL) and gait speed, and associated factors in subjects receiving home-based rehabilitation after hospital admission for heart failure.

METHODS

A total of 1,055 patients (mean age 82 ± 8 years SD) receiving post-admission home care services for heart failure. Subjects were included if they were referred for home-care rehabilitation after inpatient admission with ICD-9 code indicating heart failure at inpatient discharge, primary home care, or co-morbid diagnosis on admission Outcome and Assessment Information Set version-C (OASIS-C). Change in total ADL score was described and adjusted for significant baseline factors/covariates using a generalized linear model. Factors predictive of exceeding the ADL score Minimal Detectable Change (MDC) were identified with multiple variable logistic regression.

RESULTS

Mean change in total ADL score from admission to discharge was 1.6 ± 1.2, the mean change for gait speed was 0.17 ± 0.21 m/s, and the minimum detectable change (MDC) (1.3) was exceeded by 57% of subjects. Improvement in mean ADL score was significantly predicted by age, baseline total ADL score, baseline gait speed score, cognitive-behavioral status, and living situation (R² = 42%).

CONCLUSIONS

Patients with heart failure receiving home-based rehabilitation services make significant improvements in ADL function and gait performance. Greater ADL improvements are associated with younger age, faster gait speed at baseline, and greater impairment of baseline ADL scores. Age, baseline gait speed, and ADL composite score are significantly related to making a change beyond measurement error in ADL change score.

Assessment of Activity of Daily Living Among Older Adult Patients in Home Healthcare and Skilled Nursing Facilities: An Integrative Review

Older adult's ability to self-manage illness is dependent on their ability to perform activities of daily living (ADL). Forty-five percent of those older than 65 years will have ongoing clinical needs after hospital discharge and require postacute care (PAC) services in settings such as home healthcare (HHC) and skilled nursing facilities (SNF). The Improving Medicare Post-Acute Care Transformation Act of 2014 requires PAC providers to begin collecting and reporting ADL data to build a coordinated approach to payment and standardize patient assessments and quality measurement. The aim of this integrative review was to compare the methods of assessing ADLs in HHC to SNF. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement was used to ensure results were reported systematically. A scientific literature search without date restriction within the PubMed and Cumulative Index of Nursing and Allied Health Literature databases was conducted. Two independent investigators assessed study quality using the quality appraisal instrument developed by Kmet et al. Study quality was high. Of the 18,749 articles identified by the search, 8 met inclusion criteria and four tools were identified that are used to assess ADLs in SNF and HHC. Although SNF and HHC collect similar ADL information, the range of content covered, item definitions, scoring, and psychometrics are not comparable across settings.

Measurement of the severity of disability in community-dwelling adults and older adults: interval-level measures for accurate comparisons in large survey data sets

OBJECTIVES

To (1) create a single metric of disability using Rasch modelling to be used for comparing disability severity levels across groups and countries, (2) test whether the interval-level measures were invariant across countries, sociodemographic and health variables and (3) examine the gains in precision using interval-level measures relative to ordinal scores when discriminating between groups known to differ in disability.

DESIGN

Cross-sectional, population-based study.

SETTING/PARTICIPANTS

Data were drawn from the Survey of Health, Ageing and Retirement in Europe (SHARE), including comparable data across 16 countries and involving 58 489 community-dwelling adults aged 50+.

MAIN OUTCOME MEASURES

A single metric of disability composed of self-care and instrumental activities of daily living (IADLs) and functional limitations. We examined the construct validity through the fit to the Rasch model and the know-groups method. Reliability was examined using person separation reliability.

RESULTS

The single metric fulfilled the requirements of a strong hierarchical scale; was able to separate persons with different levels of disability; demonstrated invariance of the item hierarchy across countries; and was unbiased by age, gender and different health conditions. However, we found a blurred hierarchy of ADL and IADL tasks. Rasch-based measures yielded gains in relative precision (11-116%) in discriminating between groups with different medical conditions.

CONCLUSIONS

Equal-interval measures, with person-invariance and item-invariance properties, provide epidemiologists and researchers with the opportunity to gain better insight into the hierarchical structure of functional disability, and yield more reliable and accurate estimates of disability across groups and countries. Interval-level measures of disability allow parametric statistical analysis to confidently examine the relationship between disability and continuous measures so frequent in health sciences (eg, cholesterol, blood pressure, C reactive protein).

Risk Factors for Hospitalization Among Medicare Home Care Patients

This study determined factors associated with an increased risk of ending Medicare home health care because of hospitalization and examined specific types of and reasons for hospitalization. Sample members ( N = 922) were followed from admission to discharge as they received home care from Ohio Medicare-certified home care agencies between December 1999 and March 2002. Potential patient-level risk factors were predisposing, enabling, or need variables, and an agency-level variable denoting hospital affiliation or free-standing status was examined as a second-level risk factor. Among those hospitalized (18.3%), more than 80.0% experienced emergency hospitalizations, mostly for acute exacerbations of chronic diseases. Statistically significant risk factors for hospitalization included dyspnea severity, functional disability level, skin or wound problems, diabetes, case mix score, and guarded rehabilitation prognosis. Home care agencies might reduce hospitalizations by using clinical prognosis as a key resource for team communication and by helping patients and families anticipate potential acute exacerbations of chronic diseases and manage these events at home.

Evaluation of a Diabetes Disease Management Home Care Program

Diabetes disease management home care programs provide education, promote self-care, and empower patients. Guided by Orem’s self-care deficit nursing theory, this program evaluation project examined outcomes of home care for patients with diabetes. Three groups of diabetes patients were studied. Group 1 (n = 50) and 2 (n = 51) participants received traditional diabetes home care. Group 3 (n = 65) participants received experimental diabetes disease management. Patient data were obtained from medical records, a computerized billing system, and the Outcomes Assessment Information Set (OASIS). No statistically significant group differences in outcomes were found. A clinically significant finding was that approximately 50% of patients in each group were discharged with glucose levels that did not meet American Diabetes Association criteria. The project extends application of OASIS to Orem’s theory and raises questions about outcomes included in program evaluations. Larger samples are required to determine the best approach for diabetes disease management in home care.

Mining Patterns Associated With Mobility Outcomes in Home Healthcare

BACKGROUND

Mobility is critical for self-management. Understanding factors associated with improvement in mobility during home healthcare can help nurses tailor interventions to improve mobility outcomes and keep patients safely at home.

OBJECTIVES

The aims were to (a) identify patient and support system factors associated with mobility improvement during home care, (b) evaluate consistency of factors across groups defined by mobility status at the start of home care, and (c) identify patterns of factors associated with improvement and no improvement in mobility within each group.

METHODS

Outcome and Assessment Information Set data extracted from a national convenience sample of 270,634 patient records collected from October 1, 2008 to December 31, 2009 from 581 Medicare-certified, home healthcare agencies were used. Patients were placed into groups based on mobility scores at admission. Odds ratios were used to index associations of factors with improvement at discharge. Discriminative pattern mining was used to discover patterns associated with improvement of mobility.

RESULTS

Overall, mobility improved for 49.4% of patients; improvement occurred most frequently (80%) among patients who were able, at admission, to walk only with the supervision or assistance of another person at all times. Numerous factors associated with improvement in mobility outcome were similar across the groups (except for those who were chairfast but were able to wheel themselves independently); however, the number, strength, and direction of associations varied. In most groups, data mining-discovered patterns of factors associated with the mobility outcome were composed of combinations of functional and cognitive status and the type and amount of help required at home.

DISCUSSION

This study provides new data mining-based information about how factors associated with improvement in mobility group together and vary by mobility at admission. These approaches have potential to provide new insights for clinicians to tailor interventions for improvement of mobility.

Hierarchical nature of activities of daily living in the Spanish Disability Survey

Many studies have addressed the issue of dimensionality in activities of daily living (ADL) and its hierarchy, with contradictory results. This paper aims to study the unidimensional structure and the hierarchy of ADL in the Spanish Disability Survey. We analysed a sample of 8381 people aged 65 and over with at least one disability and receiving personal help with one of them. The following Rasch model properties were studied in 14 items enquiring about basic and instrumental ADL: fit to the model, reliability, unidimensionality, local independency between items and differential item functioning (DIF) by gender, age and proxy. The unidimensionality of the scale was confirmed. The final analysis of eight items showed a satisfactory fit, good reliability, local independency, unidimensionality and no DIF by age. The disability linear measure showed significant differences by gender and age. The obtained disability scale is a simple and reliable measure, and it suggests a hierarchical order of ADL and predicts a schedule of functional impairment in older adults. Rating the disability of older community-dwelling people has a predictive value that policy makers might find useful in service planning.

Assessment of an Expanded Functional Disability Scale for Older Adults With Diabetes

Although prior literature has shown the plausibility of combining the Activities of Daily Living (ADL) and Instrumental Activities of Daily Living (IADL) items to form an expanded scale for measuring the degree of functional decline, this has not been shown in older adults with diabetes who are disproportionately affected by functional disability. Using the 2009 Medicare Current Beneficiary Survey data, we evaluated the factor structure of the pooled ADL and IADL items. Based on our study comprising 2,158 community-dwelling older adults (≥65 years) with diabetes, the unidimensional model exhibited good fit. Despite well-fitting indices, high correlations were observed between the latent constructs (>.70) of the multi-factor models, suggesting a lack of discriminant validity. These findings provide empirical support for a combined scale that can comprehensively and efficiently characterize the extent of functional disability in older adults with diabetes for research, risk adjustment, and evaluation in patient-centered medical homes.

Disentangling the disabling process: insights from the precipitating events project

Among older persons, disability in activities of daily living is common and highly morbid. The Precipitating Events Project (PEP Study), an ongoing longitudinal study of 754 initially nondisabled, community-living persons, aged 70 or older, was designed to further elucidate the epidemiology of disability, with the goal of informing the development of effective interventions to maintain and restore independent function. Over the past 16 years, participants have completed comprehensive, home-based assessments at 18-month intervals and have been interviewed monthly to reassess their functional status and ascertain intervening events, other health care utilization, and deaths. Findings from the PEP Study have demonstrated that the disabling process for many older persons is characterized by multiple and possibly interrelated disability episodes, even over relatively short periods of time, and that disability often results when an intervening event is superimposed upon a vulnerable host. Given the frequency of assessments, long duration of follow-up, and recent linkage to Medicare data, the PEP Study will continue to be an outstanding platform for disability research in older persons. In addition, as the number of decedents accrues, the PEP Study will increasingly become a valuable resource for investigating symptoms, function, and health care utilization at the end of life.

Functional status in the young-old: establishing a working prototype of an extended-instrumental activities of daily living scale

BACKGROUND

Instrumental activities of daily living (IADLs) exhibit strong predictive power for the presence of dementia and mild cognitive impairment. However, IADLs are often less effective in younger cohorts or in healthy community-dwelling samples, presenting with large ceiling effects. This study aimed to construct an IADL scale with an extended range. An effort was made to incorporate leisure activity tasks that were more stimulating, and potentially more challenging, into a set of traditional IADLs.

METHODS

Beginning with a set of IADL and leisure activity items, nonparametric item response theory methodology was used to construct a scale with appropriate dimensionality, monotonicity, item discrimination power, and scalability within a large cohort of young-old (aged 65-75). Dimensionality was further scrutinized by principal component analysis of the residuals. The predictive validity of the resulting scale for poor cognitive performance was evaluated using logistic regression.

RESULTS

A reliable (ρ = .73) unidimensional construct was established, meeting the Mokken item response theory criteria of medium scalability. Excluding demented participants, the adjusted model proved sensitive to relatively subtle cognitive deficits; each additional task endorsed (nine-item scale) significantly decreased the odds of being in the bottom quarter of composite domains relating to processing speed (odds ratio = 0.73 [confidence interval: 0.56-0.97], p < .05) and visuospatial ability (odds ratio = 0.70 [confidence interval: 0.73-0.87], p < .01).

CONCLUSIONS

A reliable extended-IADL scale was constructed meeting item response theory assumptions relating to unidimensionality, monotonicity, and invariant item ordering. The range of measurement extends well beyond traditional IADL scales. Finally, the scale appears to be sensitive to cognitive differences within the normal spectrum.

Predictors of functional and gait outcomes for persons poststroke undergoing home-based rehabilitation

BACKGROUND

The literature on the impact of home-based rehabilitation on functional outcomes for patients after stroke is limited. The purpose of this study was to describe the outcomes of home-based rehabilitation (HBR) on functional and gait performance for patients after stroke and associated factors that contribute to better outcomes after an episode of care.

METHODS

The nature of the study design was retrospective and the settings used were home care services. The total number of subjects receiving home care services after stroke was 213 (mean age 76.5 ± 9 years, 51% female). Treatment records for patients receiving HBR in 2010 were reviewed at the start of care and discharge. The primary outcome measure was a change in a gait speed and activities of daily living (ADL) performance between admission and discharge from home health care services. The composite score to calculate overall functional status (Outcome Information and Assessment Set-version C [OASIS-C]) was used. Mean change in ADL and gait scores and factors predictive of improvement were identified using an analysis of covariance and multivariate linear models. The main outcome measures were change in the OASIS-C composite scores and gait speed.

RESULTS

After adjustment for age and ADL score at the start of care, discharge from skilled nursing or long-term facilities, presence of confusion most of the times, cognitive impairment, and memory deficits were negatively associated with an improvement in functional scores (ADL). Living in congregate facilities was also negatively associated with an improvement in gait speed. The best multivariate model included age, baseline ADL composite scores, confusion status, and gait speed at the start of care, which predicted 41% of the variance in ADL score changes over the course of intervention.

CONCLUSIONS

Gait speed and ADL scores at the start of care had largest influence on functional and gait improvement. Type of discharge facility, confusion status, and living arrangement had effects on HBR outcomes for stroke survivors.

The Outcome and Assessment Information Set (OASIS): a review of validity and reliability

The Outcome and Assessment Information Set (OASIS) is the patient-specific, standardized assessment used in Medicare home health care to plan care, determine reimbursement, and measure quality. Since its inception in 1999, there has been debate over the reliability and validity of the OASIS as a research tool and outcome measure. A systematic literature review of English-language articles identified 12 studies published in the last 10 years examining the validity and reliability of the OASIS. Empirical findings indicate the validity and reliability of the OASIS range from low to moderate but vary depending on the item studied. Limitations in the existing research include: nonrepresentative samples; inconsistencies in methods used, items tested, measurement, and statistical procedures; and the changes to the OASIS itself over time. The inconsistencies suggest that these results are tentative at best; additional research is needed to confirm the value of the OASIS for measuring patient outcomes, research, and quality improvement.

Rasch-based scoring offered more precision in differentiating patient groups in measuring upper limb function

OBJECTIVE

To compare the discriminatory ability of Rasch-based and summative scoring in the context of assessing upper limb function of patients with stroke.

STUDY DESIGN AND SETTING

Data were from a cohort study of 497 adults with stroke undergoing physiotherapy. Upper limb function was assessed at admission and discharge using the upper limb subscale of the Motor Assessment Scale (UL-MAS). Rasch analysis was used to transform raw UL-MAS scores into interval measures. A relative precision (RP) index was used to differentiate patients by discharge destination.

RESULTS

The analysis confirmed the unidimensional structure of UL-MAS at both admission and discharge and demonstrated the adequate fit of the items. The RP index favored the Rasch-based scoring over the summative scoring in differentiating between the two patient groups, with significant gains in precision at admission (15%) and discharge (11%). When examining patients in the upper or lower quartile of UL-MAS, the gains in precision were statistically significant in favor of the Rasch-based scoring, with 20% precision at admission and 19% precision at discharge.

CONCLUSION

Rasch-based scoring was more precise in differentiating patient groups by discharge destination than the summative scoring used to measure upper limb function, especially at the extreme range of the scale.

Risk factors for hospitalization in a national sample of medicare home health care patients

Acute care hospitalization during or immediately following a Medicare home health care (HHC) episode is a major adverse outcome, but little has been published about HHC patient-level risk factors for hospitalization. The authors determined risk factors at HHC admission associated with subsequent acute care hospitalization in a nationally representative Medicare patient sample (N = 374,123). Hospitalization was measured using Medicare claims data; risk factors were measured using Outcome Assessment and Information Set data. Seventeen percent of sample members were hospitalized. Multivariate logistic regression analysis found that the most influential risk factors (all p < .001) were skin wound as primary HHC diagnosis, clinician-judged guarded rehabilitation prognosis, congestive heart failure as primary HHC diagnosis, presence of depressive symptoms, dyspnea severity, and Black, compared to White. HHC initiatives that minimize chronic condition exacerbations and actively treat depressive symptoms might help reduce Medicare patient hospitalizations. Unmeasured reasons for higher hospitalization rates among Black HHC patients deserve further investigation.

Continuity in the Provider of Home Health Aide Services and the Likelihood of Patient Improvement in Activities of Daily Living

Receiving care from the same provider over time is an important dimension of continuity in home healthcare. In the present study, we examine whether continuity in the provider of home health aide services is associated with the likelihood of improvement in Activities of Daily Living (ADLs). To address this research question, we retrieved clinical and administrative records from a population of cases receiving home health aide services at a large, urban, not-for-profit Medicare-certified home healthcare agency ( N =16,541). Results revealed that cases which had high levels of continuity in the provider of home health aide services had a significantly greater likelihood of improvement in ADLs compared to cases with the lowest level of continuity.

Applying the ACR Preliminary Diagnostic Criteria in the Diagnosis and Assessment of Fibromyalgia

BACKGROUND

Fibromyalgia (FM) is characterized by chronic widespread pain with a low pain threshold. The aim of this study was to compare two criteria for the diagnosis and assessment of FM and to analyze the correlation and agreement between the 1990 and 2010 American College of Rheumatology (ACR) preliminary diagnostic criteria for FM.

METHODS

We studied 98 patients who had already been diagnosed as having FM using the 1990 criteria or 2010 preliminary criteria. Tender point examination, FM impact questionnaire (FIQ) and pain visual analog scale (VAS) were obtained. According to the preliminary criteria, FM was quantified as WPI (widespread pain index) and the SS scale (symptom severity) and the two criteria were compared.

RESULTS

Among 98 patients, 78.6% of the patients were diagnosed with the 1990 ACR criteria and 93.9% of the patients were diagnosed with the ACR preliminary diagnostic criteria, and there was also significant agreement between the two criteria (P < 0.01). There was a correlation with the WPI and the tender point, with the SS and the FIQ, and with the sum of the WPI and SS and the FIQ.

CONCLUSIONS

The ACR preliminary diagnostic criteria for FM were in agreement with the 1990 ACR criteria during the disease course. The preliminary criteria were the more sensitive method than the 1990 criteria. In addition, the 2010 criteria might have advantages since it is easy to assess the physical and psychological symptoms and can be quantified. Therefore, the ACR preliminary diagnostic criteria for FM could be used more conveniently for clinical diagnosis and follow up evaluation after starting management of FM.

Predictors of functional capacity changes in a US population of Medicare home health care (HHC) patients with heart failure (HF)

PURPOSE

Functional capacity is widely recognized as a key factor in maintaining the ability of older people to live independently and safely at home. Promoting functional capacity is an important priority particularly in HHC. The purpose of the study was to examine predictors of functional capacity change among HHC patients with HF.

MATERIALS AND METHODS

Clinical and administrative data from 2005 from the Medicare Chronic Conditions Warehouse were linked at the population level for HHC patients with a primary diagnosis of HF. The primary outcome was change in functional capacity score from HHC admission to HHC discharge.

RESULTS

Over the course of the episode (M=44 days), most (70%) patients improved, 15.6% stayed the same, and 14.4% declined in activities of daily living (ADL) scores. The mean change score was modest (mean=-0.74, SD=1.11) with a median change of -0.58. Multivariate analyses (R(2)=0.23) showed that the largest influence was the admission ADL score followed by receiving any physical therapy (PT), admission ability to manage oral medications, cognitive functioning, rehabilitation prognosis, and urinary incontinence.

DISCUSSION

There is a modest rate of improvement from admission to discharge that likely represents the progressive nature of HF and/or the short time frames over which HHC is provided. Providers may want to use the predictive factors to identify patients most at risk for functional decline.

Calibrating ADL-IADL scales to improve measurement accuracy and to extend the disability construct into the preclinical range: a systematic review

BACKGROUND

Interest in measuring functional status among nondisabled older adults has increased in recent years. This is, in part, due to the notion that adults identified as 'high risk' for functional decline portray a state that is potentially easier to reverse than overt disability. Assessing relatively healthy older adults with traditional self-report measures (activities of daily living) has proven difficult because these instruments were initially developed for institutionalised older adults. Perhaps less evident, are problems associated with change scores and the potential for 'construct under-representation', which reflects the exclusion of important features of the construct (e.g., disability). Furthermore, establishing a formal hierarchy of functional status tells more than the typical simple summation of functional loss, and may have predictive value to the clinician monitoring older adults: if the sequence task difficulty is accelerated or out of order it may indicate the need for interventions.

METHODS

This review identified studies that employed item response theory (IRT) to examine or revise functional status scales. IRT can be used to transform the ordinal nature of functional status scales to interval level data, which serves to increase diagnostic precision and sensitivity to clinical change. Furthermore, IRT can be used to rank items unequivocally along a hierarchy based on difficulty. It should be noted that this review is not concerned with contrasting IRT with more traditional classical test theory methodology.

RESULTS

A systematic search of four databases (PubMed, Embase, CINAHL, and PsychInfo) resulted in the review of 2,192 manuscripts. Of these manuscripts, twelve met our inclusion/exclusion requirements and thus were targeted for further inspection.

CONCLUSIONS

Manuscripts presented in this review appear to summarise gerontology's best efforts to improve construct validity and content validity (i.e., ceiling effects) for scales measuring the early stages of activity restriction in community-dwelling older adults. Several scales in this review were exceptional at reducing ceiling effects, reducing gaps in coverage along the construct, as well as establishing a formal hierarchy of functional decline. These instrument modifications make it plausible to detect minor changes in difficulty for IADL items positioned at the edge of the disability continuum, which can be used to signal the onset of progressive type disability in older adults.

Racial and ethnic group variations in service use in a national sample of Medicare home health care patients with type 2 diabetes mellitus

Type 2 diabetes mellitus is known to affect adults in racial and ethnic minority groups disproportionately. When diabetes mellitus-related symptoms lead to the need for skilled care in the community-dwelling Medicare population, physicians can order the Medicare home health care (HHC) benefit, and Medicare-certified home health agencies can deliver it. Little is known about the extent to which racial and ethnic disparities exist in types and patterns of HHC services delivered to Medicare beneficiaries with diabetes mellitus when they are approved for the Medicare HHC benefit. This was examined by comparing racial and ethnic groups in terms of measures of HHC service use in a nationally representative sample of Medicare HHC beneficiaries with a primary diagnosis of type 2 diabetes mellitus. Uniform clinical data from the Outcome and Assessment Information Set were linked with Medicare HHC claims for beneficiaries who received a complete episode of HHC in 2002. In the study sample (n=9,838), 62% of participants self-identified as white, 22% African American, 12% Hispanic, and 3% Asian. Nearly all (99%) participants in all racial and ethnic groups received skilled nursing services. Controlling for numerous sociodemographic and health-related covariates and geographic region of the country, African-American participants received fewer nurse visits per week and fewer visits per week from all clinical disciplines combined than whites (both P<.001), and Hispanic participants were less likely than whites to receive physical therapy (adjusted odds ratio (AOR)=0.640, 95% confidence interval (CI)=0.543-0.754, P<.001) or home health aide (AOR=0.716, 95% CI=0.582-0.880, P=.002) services. Lower use of skilled nursing and rehabilitation services by African Americans and of rehabilitation services by Hispanics warrant further clinical and research attention.

Functional status outcome measures in home health care patients with heart failure

Elderly, chronically ill patients' ability to stay at home is dependent on their capacity to perform activities of daily living (ADLs). The Outcome and Assessment Information Set (OASIS) defines ADLs and can be evaluated in various ways. The purpose of this research was to evaluate these approaches and make recommendations for use in research. Several different approaches to the evaluation of functional status were done using ADLs (ambulation, bathing, dressing lower body, dressing upper body, feeding, grooming, toileting, and transferring) scored individually and as indices. Each approach has advantages and disadvantages depending on the research question being asked. The ADL change index score provided the most comprehensive analysis of functional status change although the categorical scores are useful for simple approaches.

Elder Abuse in Long-Term Care: Types, Patterns, and Risk Factors

The authors investigated types and patterns of elder abuse by paid caregivers in long-term care and assessed the role of several risk factors for different abuses and for multiple abuse types. The results are based on a 2005 random-digit-dial survey of relatives of persons in long-term care. We computed occurrence rates and conditional occurrence rates for each of six abuse types: physical, caretaking, verbal, emotional, neglect, and material. Among older adults who have experienced at least one type of abuse, more than half (51.4%) have experienced another type of abuse. Physical functioning problems, activities of daily living limitations, and behavioral problems are significant risk factors for at least three types of abuse and are significant for multiple abuse types. The findings have implications for those monitoring the well-being of older adults in long-term care as well as those responsible for developing public health interventions.

Validity testing the Outcomes and Assessment Information Set (OASIS)

This study evaluated the criterion validity of the Outcome and Assessment Instrument Set (OASIS) items that measure activities of daily living (ADLs), instrumental activities of daily living (IADLs), cognitive functioning, and depression. A convenience sample of patients (n = 203) from five home care agencies participated in the study. Patient OASIS items were compared to data collected using gold standard instruments. Correlations range from .44 to .69 for ADLs and .20 to .68 for IADLs. A correlation of .62 was found for cognitive functioning while correlations for depressive symptoms are .36 and .26. OASIS ADLs and cognitive status items are sufficiently valid, but the OASIS depression item is not sufficiently sensitive to the prevalence of these conditions.

Defining and Measuring Quality Outcomes in Long-Term Care

The US health care industry increasingly agrees that sharing information about quality of care is necessary to stimulate providers' efforts to improve the quality of health care. The availability of mandated, uniform clinical data in all nursing homes and home health agencies has facilitated the rapid adoption of public reporting of comparative quality data. This paper examines the conceptual and technical challenges underlying the application of information about long-term care provider quality to judge and compare the quality of care provided by nursing homes and home health agencies. In general, the impetus to apply the emerging set of quality "tools" based on mandated clinical assessments may have outstripped the evidence for their valid application in selecting top providers or for rewarding their superior performance.

Functional status decline as a measure of adverse events in home health care: an observational study

BACKGROUND

Research that examines the quality of home health care is complex because no gold standard exists for measuring adverse outcomes, and because the patient and clinician populations are highly heterogeneous. The objectives in this study are to develop models to predict functional decline for three indices of functional status as measures of adverse events in home health care and determine which index is most appropriate for risk-adjusting for future quality research.

METHODS

Data come from the Outcomes and Assessment Information Set (OASIS) from a large urban home health care agency and other agency data. Prognostic data yields 49,437 episodes, while follow-up data yields 47,684 episodes. We tested three indices defined as substantial decline in three or more (gt3_ADLs), two or more (gt2_ADLs), and one or more (gt1_ADLs) ADLs. Multivariate logistic regression determines the performance of the models for each index as measured by the c-statistic and Hosmer-Lemeshow chi square (chi2).

RESULTS

Frequencies for gt3_ADLs, gt2_ADLs, and gt1_ADLs are 212 (0.43%), 783 (1.58%), and 4,271 (8.64%) respectively. Follow-up results are comparable with frequencies of 218 (0.46%), 763 (1.60%), and 3,949 (8.28%) for each index. Gt3_ADLs does not produce valid models. The model for gt2_ADLs consistently yields a higher c-statistic compared to gt1_ADLs (0.754 vs. 0.679, respectively). Both indices' models yield non-significant Hosmer-Lemeshow chi square indicating reasonable model fit. Findings for gt2_ADLs and gt1_ADLs are consistent over time as indicated by follow-up data results.

CONCLUSION

Gt2_ADLs yields the best models as indicated by a high c-statistic and a non-significant Hosmer-Lemeshow chi2, both of which exhibit exceptional consistency. We conclude that gt2_ADLs may be preferable in defining ADL adverse events in the context of home health care.

Rasch modeling of revised token test performance: validity and sensitivity to change

The purpose of this research was to examine the validity of the 55-item Revised Token Test (RTT) and to compare traditional and Rasch-based scores in their ability to detect group differences and change over time. The 55-item RTT was administered to 108 left- and right-hemisphere stroke survivors, and the data were submitted to Rasch analysis. Traditional and Rasch-based scores for a subsample of 60 stroke survivors were submitted to analyses of variance with group (left hemisphere with aphasia vs. right hemisphere) and time post onset (3 vs. 6 months post onset) as factors. The 2 scoring methods were compared using an index of relative precision. Forty-eight items demonstrated acceptable model fit. Misfitting items came primarily from Subtest IX. The Rasch model accounted for 71% of the variance in the responses to the remaining items. Intersubtest patterns of item difficulty were well predicted by item content, but unexpected within-subtest differences were found. Both traditional and Rasch person scores demonstrated significant group differences, but only the latter demonstrated statistically significant change over time. Analysis of relative precision, however, failed to confirm a significant difference between the 2 methods. The findings generally support the RTT's validity, but a minority of items appears to respond to a different construct. Also, within-subtest differences in item difficulty suggest the need for further examination of variability in impaired language performance. Finally, the results suggest an equivocal advantage for Rasch scores in detecting change over time.

Comparative validity of seven scoring systems for the instrumental activities of daily living scale in rural elders

Lawton and Brody's eight-item Instrumental Activities of Daily Living (IADL) scale is used often with elderly patients but scored in several different ways. We scored the IADL with seven popular procedures ranging from relatively simple to complex (Guttman scores, summed and Rasch scores from dichotomous, trichotomous, and polytomous items) in a sample of rural elders (N = 231). We compared the IADL scales' prediction of concurrent cognitive functioning, depressive symptoms, psychosocial functioning, and health care use (medications, outpatient visits, inpatient days). Validity coefficients ranged from small to large among outcome variables but were highly consistent across IADL scoring procedures. Consequently, researchers and clinicians may prefer to use simpler IADL scoring procedures with this population.

Improving the quality of long-term care with better information

Publicly reporting information stimulates providers' efforts to improve the quality of health care. The availability of mandated, uniform clinical data in all nursing homes and home health agencies has facilitated the public reporting of comparative quality data. This article reviews the conceptual and technical challenges of applying information about the quality of long-term care providers and the evidence for the impact of information-based quality improvement. Quality "tools" have been used despite questions about the validity of the measures and their use in selecting providers or offering them bonus payments. Although the industry now realizes the importance of quality, research still is needed on how consumers use this information to select providers and monitor their performance and whether these efforts actually improve the outcomes of care.

The economic burden of home care for children with HIV and other chronic illnesses

OBJECTIVES

We compared types, amounts, and costs of home care for children with HIV and chronic illnesses, controlling for the basic care needs of healthy children to determine the economic burden of caring for and home care of chronically ill children.

METHODS

Caregivers of 97 HIV-positive children, 101 children with a chronic illness, and 102 healthy children were surveyed regarding amounts of paid and unpaid care provided. Caregiving value was determined according to national hourly earnings and a market replacement method.

RESULTS

Chronically ill children required significantly more care time than HIV-positive children (7.8 vs 3.9 hours per day). Paid care accounted for 8% to 16% of care time. Annual costs were $9300 per HIV-positive child and $25,900 per chronically ill child. Estimated national annual costs are $86.5 million for HIV-positive children and $155 to $279 billion for chronically ill children.

CONCLUSIONS

Informal caregiving represents a substantial economic value to society. The total care burden among chronically ill children is higher than that among children with HIV.

Data, Information, and Quality Indicators for Home Healthcare: Rapid Implementation, Whatʼs Next?

From 1999 to 2003, the home health industry in the United States moved from an environment with extremely diverse data collection protocols and little or no dissemination of quality-related information, to an environment in which uniformly collected clinical data are transformed into information and then into publicly available reports using federally mandated quality indicators. This speed to action has raised many questions about the adequacy of home healthcare data and their use as quality-monitoring tools. This article summarizes current evidence about the scientific and clinical adequacy of data currently used to measure home healthcare quality and discusses roles of a variety of policy stakeholders in implementing and refining data, information, and quality indicators that are now the cornerstones of federal home healthcare quality policy. The scientific adequacy of Outcome and Assessment Information Set data is acceptable but bears routine monitoring and review; efforts should be made to develop home healthcare quality indicators sensitive to nursing interventions and published clinical practice guidelines for specific medical conditions; and policy stakeholders should collaborate to maximize the utility of home healthcare quality reports now disseminated to consumers, providers, and insurers.

Refining the conceptual basis for rehabilitation outcome measurement: personal care and instrumental activities domain

BACKGROUND

Rehabilitation outcome measures routinely include content on performance of daily activities; however, the conceptual basis for item selection is rarely specified. These instruments differ significantly in format, number, and specificity of daily activity items and in the measurement dimensions and type of scale used to specify levels of performance. We propose that a requirement for upper limb and hand skills underlies many activities of daily living (ADL) and instrumental activities of daily living (IADL) items in current instruments, and that items selected based on this definition can be placed along a single functional continuum.

OBJECTIVE

To examine the dimensional structure and content coverage of a Personal Care and Instrumental Activities item set and to examine the comparability of items from existing instruments and a set of new items as measures of this domain.

METHODS

Participants (N = 477) from 3 different disability groups and 4 settings representing the continuum of postacute rehabilitation care were administered the newly developed Activity Measure for Post-Acute Care (AM-PAC), the SF-8, and an additional setting-specific measure: FIM (in-patient rehabilitation); MDS (skilled nursing facility); MDS-PAC (postacute settings); OASIS (home care); or PF-10 (outpatient clinic). Rasch (partial-credit model) analyses were conducted on a set of 62 items covering the Personal Care and Instrumental domain to examine item fit, item functioning, and category difficulty estimates and unidimensionality.

RESULTS

After removing 6 misfitting items, the remaining 56 items fit acceptably along the hypothesized continuum. Analyses yielded different difficulty estimates for the maximum score (eg, "Independent performance") for items with comparable content from different instruments. Items showed little differential item functioning across age, diagnosis, or severity groups, and 92% of the participants fit the model.

CONCLUSIONS

ADL and IADL items from existing rehabilitation outcomes instruments that depend on skilled upper limb and hand use can be located along a single continuum, along with the new personal care and instrumental items of the AM-PAC addressing gaps in content. Results support the validity of the proposed definition of the Personal Care and Instrumental Activities dimension of function as a guide for future development of rehabilitation outcome instruments, such as linked, setting-specific short forms and computerized adaptive testing approaches.