Functional Status Instruments Research Articles

Measurement of function in older adults transitioning from hospital to home: an integrative review

Older adults often experience decline in functional status during the transition from hospital to home. In order to determine the effectiveness of interventions to prevent functional decline, researchers must have instruments that are reliable and valid for use with older adults. The purpose of this integrative review is to: (1) summarize the research uses and methods of administering functional status instruments when investigating older adults transitioning from hospital to home, (2) examine the development and existing psychometric testing of the instruments, and (3) discuss gaps and implications for future research. The authors conducted an integrative review of forty research studies that assessed functional status in older adults transitioning from hospital to home. This review reveals important gaps in the functional status instruments' psychometric testing, including limited testing to support their validity and reliability when administered by self-report and limited evidence supporting their ability to detect change over time.

Characteristics of and Barriers to Functional Status Assessment in Assisted Living.

The most commonly used functional status (FS) instruments were examined to determine the validity, reliability, sensitivity, and specificity to change and feasibility in residents in an assisted living facility (ALF). Twenty-six ALF residents were assessed weekly for up to 8 months using six instruments. Group and single-subject analyses were used to examine associations between instruments and acute events. Two were problematic initially (Katz Index of Independence in Activities of Daily Living and hand grip) and were excluded early in the study. Of the remaining instruments, only the Barthel Index and Resident Assessment Instrument had acceptable psychometric profiles. However, these instruments were either not feasible in this environment or did not capture the full range of FS in this population. The current study's findings suggest that instruments commonly used to measure FS may be inadequate for this population and environment. These findings may be used to develop assessment methods for ALF residents that capture both the full range of FS in ALF settings as well as acute and long-term changes in functioning.

Comparison of Functional Status Instruments in HIV-Infected Adults on Effective Antiretroviral Therapy

Background: The best method for assessment of functional status in human immunodeficiency virus type 1 (HIV-1) infected persons is unknown. Objective: We hypothesized that 3 instruments to assess frailty or disability in elderly populations would perform similarly in HIV-1–infected persons. Methods: HIV-infected subjects 45 to 65 years old with plasma HIV-1 RNA <48 copies/mL were classified prospectively as low, moderate, or high function by Fried's frailty phenotype (FFP), the Short Physical Performance Battery (SPPB), and 400-m walk test. Functional instrument agreement was evaluated by weighted kappa statistic, and relationships with demographic or clinical factors were evaluated by odds ratios (OR). Results: There were 359 participants (85% male, mean age 52 years, mean CD4+ lymphocyte count 551 cells/µL) who were evaluated. Three percent to 8% were low, 31% to 51% were moderate, and 42% to 62% were high function. FFP, SPPB, and 400-m walk test had moderate agreement for functional classification (61%-64%; κ = 0.34-0.41). Across instruments, lower reported physical activity (OR ≯ 5.5; P ≤ .005), no current employment (OR ≯ 4.2; P < .02), arthritis (OR ≯ 6.5; P < .02), neurologic disease (OR ≯ 2.6; P < .05), debilitating pain (OR ≯ 5.4; P < .008), psychiatric disease (OR ≯3.1; P < .03), more comorbidities (OR ≯ 3.6; P ≤ .005), and more non-antiretroviral therapy medications (OR ≯ 3.5; P ≤ .01) were associated with lower function. Current CD4 <200 cells/µL was more likely among low-function (11%) than high-function (2%) persons on FFP (P = .04); other HIV-related characteristics were not significantly different (P > .05) between functional categories on any instrument. Conclusions: Moderate functional impairment is common among middle-aged HIV-infected persons, with similar frequencies of impairment detected by 3 instruments. Reduction in comorbid disease, increased physical activity, and improved pain symptom management could reduce functional impairment among persons aging with HIV-infection.

On “Lower Limb Functional Index…” Gabel CP, Melloh M, Burkett B, Michener LA. Phys Ther. 2012;92:98–110.

We were interested to read the article by Gabel and colleagues,1 who conducted a head-to-head comparison study of the psychometric properties of the Lower Extremity Functional Scale (LEFS),2 an instrument we developed in 1999, and the Lower Limb Functional Index (LLFI), an instrument developed by the authors. We have long been advocates of head-to-head comparisons of competing instruments to determine which has the greatest potential to positively affect clinical care.3 We would like to make some general comments regarding the conceptual framework, and then make more specific comments regarding the methods and literature interpretation in Gabel and colleagues' article. We developed the LEFS2 based on the World Health Organization's model of disability and handicap.4 The more contemporary terms consistent with the current version of the International Classification of Functioning, Disability and Health (ICF)5 that guided instrument development are “activity limitations” and “participation restrictions.” Because our focus was on people with musculoskeletal disorders of the lower extremity, all of the items in our scale captured the person-level activity limitations and participation restrictions most relevant to people with disorders of the lower extremity. Notably absent from the LEFS are questions related to impairments (eg, pain, joint stiffness) or mental health status (eg, irritability, depression). Our rationale for this approach was that we saw problems with other functional status instruments available at the time because they combined questions related to impairments, such as pain and joint stiffness, with items dealing with person-level function and items related to psychological distress. An example of …

Effect of Psoriatic Arthritis According to the Affected Categories of the International Classification of Functioning, Disability and Health

To determine the categories of the International Classification of Functioning, Disability and Health (ICF) checklist and core sets of rheumatoid arthritis and ankylosing spondylitis frequently occurring in people with psoriatic arthritis (PsA) and to compare the number of such categories with scores on self-report measures of participation restrictions and activity limitations. Data were collected from 94 patients with PsA attending rheumatology clinics in 6 centers. For each ICF category affected by PsA in at least 30% of patients, the percentage of such patients was determined for Body Structures, Body Functions, Activities and Participation, and Environmental Factors. A count of all affected categories by ICF chapter was compared to patient self-report scores on a number of functional and health status instruments using Spearman's correlation. There were 25 categories in the Body Functions section, 6 categories in the Body Structures section, and 51 categories in the Activities and Participation section that were relevant in at least 30% of participants. Thirteen Environmental Factors were facilitating and 1 Environmental Factor (climate) was a barrier in at least 30% of participants. The number of involved Activities and Participation categories by chapter did not correlate in predictable ways with self-report measures of participation restrictions and activity limitations. PsA is associated with a wide range of impairments, limitations, and restrictions across the ICF categories. People with PsA find environmental factors to be helpful more often than to be barriers. The unexpected pattern of correlation between ICF chapters and self-report measures suggests the need for a better way of quantitatively representing the ICF concepts.

The Prognostic Value of Measuring Health-Related Quality of Life in Hospice Patients

Better prognostic instruments are sorely needed for patients near the end of life. Health-related quality of life instruments designed for hospice patients have not been previously studied for their prognostic properties. This study evaluated the prognostic property of the Missoula-Vitas Quality of Life Index (MVQOLI) with hospice patients. A prospective, cross-sectional cohort design included all consecutive patients admitted to a hospice over a 19-month period. At admission to hospice, patients were asked to complete an MVQOLI. In addition, hospice nurses completed three functional status instruments. All patients were followed until death, study closure, or loss to follow-up. The sample included 1047 patients, but only 231 (22%) were able to complete an MVQOLI at admission. Functional status data were collected on nearly all of the patients. The Karnofsky performance score, modified activity of daily living score, and descriptive symptom score were significantly associated with survival time. Using Cox regression models these functional status assessments were strongly associated with survival time (p<0.001). However, the MVQOLI scores were not significantly associated with survival time, except for the function subscale (p=0.045). The MVQOLI global, total, and four of the five weighted-domain baseline scores were not associated with survival time in hospice patients. Other methods for prognostication at the end of life are needed.

Knee Bracing for Unicompartmental Osteoarthritis

Unicompartmental osteoarthritis of the knee affects millions of individuals. Most nonsurgical management of this progressive disease is primarily directed at reducing inflammation and pain with medication. Evidence supports the clinical efficacy of bracing for managing osteoarthritis of the knee. In some patients, bracing significantly reduces pain, increases function, and reduces excessive loading to the damaged compartment. A variety of health and functional status instruments, as well as radiologic techniques and biomechanical investigations, has been used to evaluate the unloading capabilities of these braces. Although changes in angulation are relatively minimal, the braces have been shown to load share and thus reduce the stresses in the degenerated medial compartment of the knee.

The evolution of research on disability in old age

Aging Clin Exp Res, Vol. 17, No. 3 165 Assessment of functional status has been formalized in medical practice since Karnofsky proposed an instrument in 1948 to evaluate patients undergoing cancer therapy and in geriatric practice since Katz introduced the activities of daily living (ADL) in 1963 (1, 2). The field grew rapidly and by 1984 Feinstein identified 43 different indexes of ADL for use in patient care and population research (3). In the two decades since then the field has flourished, with widespread utilization of functional status instruments in surveys of the older population, epidemiologic studies, clinical research, randomized controlled trials and clinical practice. This issue of the Journal has a variety of articles that demonstrate that the field of disability research is alive and well, with many exciting innovations. The issue can be viewed as a microcosm of the kinds of research being widely done in the field of disability and therefore serves as an excellent basis for reviewing these varied applications. We find here examples of how functional assessment plays an important role in public health, prevention, clinical care, and improving our basic understanding of the mechanisms whereby disease leads to disability. An impressive aspect that speaks to the vitality of the field is the wide geographic origin of the disability-related papers in this issue alone, with investigators from Japan, Taiwan, the US, Germany, Italy, France, the Netherlands, Norway, and Belgium making contributions. An important function of public health is to evaluate the population’s health status and track changes in important conditions. Assembling data on total and causespecific mortality, disease incidence and health care utilization is an important part of this effort, but characterizing the disability status of the older population adds an important dimension to what the disease and death statistics tell us. Downward trends in disability prevalence have been documented in several countries and, in this issue, Peres et al. present strong evidence that mobility and instrumental ADLs, but not ADLs, have The evolution of research on disability in old age

Symptom status and functional status outcomes: humanistic outcomes in obesity disease management.

Introduction Obesity is a complex, chronic health problem that is associated with increased mortality, morbidity, and health care costs, as well as decreased life quality (1–6). “The pathway to obesity is a complex journey,” involving biologic and genetic, emotional, social, and cultural factors (7). Changes in the U.S. health care delivery system, including managed care or disease management approaches, necessitate the development of systems that can be used to assess quality of care and demonstrate accountability in the health care of obese populations. Inherent in this is the identification of outcome, intermediate, and process measures (8,9). Disease management outcome measures must meet identified standards for scientific validity, relevance, and feasibility as outlined in the charge to the Team on Developing Obesity Outcomes and Learning Standards (TOOLS) Task Force of the North American Association for the Study of Obesity (NAASO) (10). The purpose of this paper is to recommend obesity disease management outcome measures to assess symptom status and functional status of populations in outcomes research evaluating the effectiveness of the management of obesity (grades I to III).

PAM19: A REVIEW OF FUNCTIONAL STATUS MEASURES FOR WORKERS WITH UPPER EXTREMITY DISORDERS

OBJECTIVES: This review identifies instruments for measuring functional status among workers with mild-to-moderate disorders of the upper extremity. Functional status measures correlate pain and discomfort to performance, with direct, practical relevance to employers and workers. While many functional status measures exist for patients with severe or degenerative illness, few measures were designed for relatively healthy active workers. In fact, the impact of mild-to-moderate disorders on the workforce is largely unknown. The recently released OSHA Ergonomics Program Standard has given this issue a new sense of urgency. The intent is to give investigators a tool for choosing appropriate functional status measures in a specific research or clinical context. METHODS: To identify self-reported functional status instruments for upper extremity disorders among workers, a Medline literature search was conducted for English-language publications between the years 1966 and 2000. Keywords included: carpal tunnel syndrome, functional status, health surveys, musculoskeletal, occupational health, outcome measures, questionnaire, neck, upper extremity, and worker. In selecting functional status instruments for review, three criteria were used: 1) Relevance to neck and upper extremity conditions (indicated by question content); 2) Assessment among workers; and 3) Relevance to mild-to-moderate disorders (indicated by level of severity). Parameters of interest were validity, reliability, and responsiveness to change. RESULTS: Among 13 functional status instruments reviewed, six measures were tested among workers, including three measures relevant for mild-to-moderate disorders: the Nordic Musculoskeletal Questionnaire, Upper Extremity Questionnaire, and Neck and Upper Limb Instrument. CONCLUSIONS: The identification of three functional status measures should encourage their use in studies, to improve communication among investigators. Further research is needed to address neglected aspects of measurement—specifically, for mild-to-moderate upper extremity disorders among workers—and to standardize valid and reliable instruments.

Responsiveness of general health status in chronic low back pain: a comparison of the COOP Charts and the SF-36

The objective of this study was to compare the responsiveness and assess the concurrent validity of two functional health status instruments, the Dartmouth COOP charts and the SF-36 in chronic low-back pain (CLBP) patients. The data came from 129 of 174 patients who participated in a randomized clinical trial of the therapeutic management of CLBP. Reliable and valid disease-specific outcomes, patient-rated low-back pain and disability, were used as external criteria (EC) to identify improved and non-improved patients. Unpaired t-statistics and receiver operating characteristic (ROC) curve calculations were used to quantify responsiveness. The two instruments had sufficient and very similar responsiveness using both EC. Comparisons between improved and non-improved patients for the COOP charts and SF-36, respectively, using pain as EC, yielded differences which translated into large effect sizes (0.8 and 0.7) ( P=0.0008 and 0.003). Using disability as EC, differences of moderate effect size were found (0.5 and 0.6) ( P=0.02 and 0.002). The ROC curve calculations using pain as EC resulted in areas under the curve of 0.76 (95% CI: 0.64, 0.88) for the COOP charts, and 0.74 (95% CI: 0.60, 0.88) for the SF-36. The corresponding areas using disability as EC were 0.67 (95% CI: 0.55, 0.79) and 0.72 (95% CI: 0.60, 0.84). The best cut-off point in both instruments for differentiating between improved and non-improved patients was approximately six percentage points. The constructs of functional health status, as reflected in the global scores of the two instruments, are highly correlated ( r=0.82). Six of the instruments’ nine dimensions are moderately to highly correlated ( r=0.52 to 0.86), and the overall canonical correlation was high ( R=0.9). In conclusion, both instruments seem equally suitable for use as outcome measures in clinical trials on CLBP. The COOP charts are faster to fill out and score.

Development and testing of the Inventory of Functional Status—Chronic Pain

Gender differences have been identified in daily activities and the importance of specific activities. Functional status instruments do not reflect these differences and may provide a biased measurement. The purpose of this 3-phase study was to develop a reliable and valid instrument for measuring functional status in women with chronic pain. The Inventory of Functional Status—Chronic Pain (IFS-CP) measures activities primarily engaged in by women and omits from scoring those activities in which the individual does not usually participate. Content validity was established at 91.5%. Reliability and further validity testing in a sample of 204 women with chronic pain found that internal consistency ranged from 0.61 to 0.94 for item to subscale, and from 0.71 to 0.89 for subscale to total scores. Test—retest reliability was 0.93. Testing of construct validity resulted in significant correlations between functional status and pain severity, pain interference [Multiphasic Pain Inventory (MPI)], perception of pain disability [Pain and Impairment Relationship Scale (PAIRS)], and quality of life (QOL Survey). The IFS-CP provides a means of comprehensively assessing the effects of pain on the functional status of women.

Otitis media health status evaluation: a pilot study for the investigation of cost-effective outcomes of recurrent acute otitis media treatment.

There are no reliable and valid instruments that measure otitis media clinical or functional health status in children ages 1 to 3 years. This study develops and tests three new instruments of clinical and functional otitis health status: the Otitis Media Clinical Severity Index (OM-CSI), the Otitis Media Functional Status Questionnaire (OM-FSQ), and the Otitis Media Diary (OMD). The OM-CSI was found to be a reliable measure of clinical acute otitis media (AOM) severity, with high internal consistency (Cronbach's alpha) scores, as well as an accurate indicator of AOM severity. The OM-FSQ and OMD were demonstrated to be reliable and valid measures of otitis-specific functional health status, with reproducible scores over time, high internal consistency alpha scores, and high correlation with measures of AOM clinical severity and other functional health status instruments. These three new instruments were also sensitive and specific indicators of AOM episodes.

Review of applicability of existing functional status measures to the study of workers with musculoskeletal disorders of the neck and upper limb

Both epidemiologic studies of the factors that contribute to the development of work-related musculoskeletal disorders of the neck and upper limb and intervention studies that test the effectiveness of workplace ergonomic and organizational changes are needed to provide empiric evidence for preventive strategies. This study reviews the relevance and comprehensiveness of existing functional status instruments for epidemiologic studies of work-related neck and upper limb disorders. Twelve domains were identified as the major areas of life affected by workers' neck and upper extremity disorder(s): work, household and family responsibilities, self-care, transportation/driving, sexual activity, sleep, social activities, recreational activities, mood, self-esteem, financial effects, and iatrogenic effects of assessments and treatment. Fifty-two functional status instruments were identified. Of these, 21 met the specified criteria as potentially relevant and were rated on the 3-point scale for relevance and comprehensiveness for each domain. None of the instruments covered all 12 domains adequately. © 1996 Wiley-Liss, Inc.

Review of applicability of existing functional status measures to the study of workers with musculoskeletal disorders of the neck and upper limb.

Both epidemiologic studies of the factors that contribute to the development of work-related musculoskeletal disorders of the neck and upper limb and intervention studies that test the effectiveness of workplace ergonomic and organizational changes are needed to provide empiric evidence for preventive strategies. This study reviews the relevance and comprehensiveness of existing functional status instruments for epidemiologic studies of work-related neck and upper limb disorders. Twelve domains were identified as the major areas of life affected by workers' neck and upper extremity disorder(s): work, household and family responsibilities, self-care, transportation/driving, sexual activity, sleep, social activities, recreational activities, mood, self-esteem, financial effects, and iatrogenic effects of assessments and treatment. Fifty-two functional status instruments were identified. Of these, 21 met the specified criteria as potentially relevant and were rated on the 3-point scale for relevance and comprehensiveness for each domain. None of the instruments covered all 12 domains adequately.

Functional status instruments: Outcome measure in the evaluation of patients with chronic obstructive pulmonary disease

The purpose of this article is to review the instruments developed to measure functional status in patients with chronic obstructive pulmonary disease. Because the ability to carry out day-to-day activities is of primary importance to patients with chronic obstructive pulmonary disease, it is necessary for clinicians to understand which instruments provide the best measures of patient activity levels. Furthermore, as a critical outcome in managed care services, pulmonary critical pathways, and patient disability, the measurement of functional status in clinical practice assumes greater relevance. Functional status instruments in this review will refer to questionnaires measuring the day-to-day activities of patients. Questionnaires reviewed will include those that provide measures of general health status with activity-specific items, as well as questionnaires specifically designed to evaluate patients with pulmonary disease. The psychometric strengths, reliability and validity, and clinical utility of the instruments will be presented.

Responsiveness of functional status in low back pain: a comparison of different instruments

This study compares the responsiveness of three instruments of functional status: two disease-specific questionnaires (Oswestry and Roland Disability Questionnaires), and a patient-specific method (severity of the main complaint). We compared changes over time of functional status instruments with pain rated on a visual analog scale. Two strategies for evaluating the responsiveness in terms of sensitivity to change and specificity to change were used: effect size statistics and receiver-operating characteristic method. We chose global perceived effect as external criterion. A cohort of 81 patients with non-specific low back pain for at least 6 weeks assessed these measures before and after 5 weeks of treatment. According to the external criterion 38 patients improved. The results of both strategies were the same. All instruments were able to discriminate between improvement and non-improvement. The effect size statistics of the instruments were higher in the improved group than in the non-improved group. For each instrument the receiver-operating characteristic curves showed some discriminative ability. The curves for the Roland Questionnaire and pain were closer to the upper left than the curves for the other instruments. The sensitivity to change of the rating of Oswestry Questionnaire was lower than that of the other instruments. The main complaint was not very specific to change. The two strategies for evaluating the responsiveness were very useful and appeared to complement each other.

Functional status after coronary artery bypass grafting and percutaneous transluminal coronary angioplasty

Two cohorts of consecutive patients of comparable age with similar preprocedure cardiac function who underwent either coronary artery bypass grafting (CABG; n = 106) or percutaneous transluminal coronary angioplasty (PTCA; n = 64) were entered into a prospective comparison study examining functional status and return to work during the first year of recovery. Patients were evaluated using standardized functional status instruments for activities of daily living, work performance, social activity, mental health and quality of social interaction at 1, 6 and 12 months after the procedure. Within the CABG group, statistically significant improvements of functional status on every subscale were noted over the 1-year follow-up. Patients undergoing PTCA demonstrated significant improvement in all dimensions except for the quality of interaction at 1 year as compared with baseline. When the 2 groups were compared, the PTCA group demonstrated greater participation than the CABG group in routine daily physical and social activities at 1 and 6 months, but this apparent advantage disappeared by 1 year. Measures of psychological functioning were better after CABG than after PTCA. A reduction in the number of those with employment occurred in both the CABG and PTCA groups, independent of physical functional status measures, which improved in both groups after the procedures. For those with employment, the CABG group reported the greatest improvement in work performance.

Pain assessment in osteoarthritis: Experience with the WOMAC osteoarthritis index

P AIN IS AN ENTIRELY personal experience, and by necessity the methods used to measure pain are difficult to validate. However, this does not mean that measurement is impossible, but rather that the methods used must be of acceptable reliability, validity (face, content, and construct), and responsiveness. In the last 50 years,’ musculoskeletal clinical metrology has undergone a progressive evolution, although much more attention has been given to measurement issues in inflammatory forms of arthritis (particularly rheumatoid arthritis) than to the more common degenerative forms of arthritis. Indeed, the clinical metrology of osteoarthritis (OA) has been relatively neglected until recent years. Thus, Doyle et al’ have modified the Ritchie Index to develop a joint count applicable to OA subjects, while Lequesne has developed two scales, for the assessment of gonarthrosis3 and coxarthrosis,4 respectively. The McGill pain questionnaire has been applied to mixed arthritis populations, and in one study was found to identify qualitative differences between patients with RA and patients with localized OA,’ although in another study no significant differences were detected between patients with inflammatory and degenerative forms of arthritis.6 Several functional status instruments have appeared in the last 10 years, and a number have recently been compared to explore their relative efficiency.’ Our own interest has been in developing WOMAC, a purposebuilt multidimensional instrument capable of measuring clinically important, patient-relevant symptoms in OA of the hip and/or knee.’

Assessment of children's health status. Field test of new approaches.

The assessment of children's health status presents unique difficulties. These include parent-child differences in reports of functioning, knowledge of what constitutes age-appropriate functioning, obtainment of accurate information for child, and demonstration of the predictivity of health status measures. Recent measures (the Functional Status II-R and instruments from the RAND Health Insurance Experiment) address physical, social, and psychologic domains of children's health. The authors modified these instruments to develop short (7 and 14 items) questionnaires (RAND, FSQ) to assess child health. Scoring on these questionnaires was compared with traditional measures of illness severity and medical service utilization. The authors also evaluated coding illness-specific and general health limitations (FSQ-S and FSQ-G, respectively). Patients included the parents of 113 children with chronic illness (100 asthmatics). Measure stability was evaluated over a 6-month period in a subset of patients. Internal consistency (Cronbach's alpha) of the seven-item RAND measure was .78, the FSQ-S .78, and the FSQ-G .73 to .89 during repeated samplings over 6 months. The FSQ-S and Rand seven-item measure were moderately correlated (.47, P less than .001). The authors observed significant correlations among alternate codings of the FSQ and RAND and between the FSQ-S, FSQ-G, RAND, and severity measure with traditional indices of medical service utilization. Parents were more likely to attribute certain functional status problems (e.g., being tired) to illness than they were other problems (e.g., moodiness or interest in things). The findings demonstrate that these measures have acceptable psychometric properties and provide preliminary evidence of construct validity in a group of young children with asthma. Using general and specific measures will provide differing pictures of a child's functioning. No single measure completely taps the impact of illness as measured by a panel of traditional indicators of illness burden and medical service utilization.