Christine M. McDonough

Comparison of EQ-5D, HUI, and SF-36-derived societal health state values among Spine Patient Outcomes Research Trial (SPORT) participants

Purpose: To compare societal values across health-state classification systems and to describe the performance of these systems at baseline in a large population of persons with confirmed diagnosis of intervertebral disc herniation (IDH), spinal stenosis (SpS), or degenerative spondylolisthesis (DS). Methods: We compared values for EQ-5D (York weights), HUI (Mark 2 and 3), SF-6D, and the SF-36-derived estimate of the Quality of Well Being (eQWB) score using signed rank tests. We tested each instrument’s ability to discriminate between health categories and level of symptom satisfaction. Correlations were assessed with Spearman rank correlations. We evaluated ceiling and floor effects by comparing the proportion at the highest and the lowest possible score for each tool. In addition, we compared proportions at the highest and lowest levels by dimension. The number of unique health states assigned was compared across instruments. We calculated the difference between those who were very dissatisfied and all others. Results: Mean values ranged from 0.39 to 0.63 among 2097 participants ages 18–93 (mean age 53, 47 female) with significant differences in pair-wise comparisons noted for all systems. Correlations ranged from 0.30 to 0.78. Although all systems showed statistically significant differences in health state values when baseline comparisons were made between those who were very dissatisfied with their symptoms and those who were not, the magnitude of this difference ranged widely across systems. Mean differences (95 CI) between those very dissatisfied and all others were 0.30 (0.269, 0.329) for EQ-5D, 0.22 (0.190, 0.241) for HUI(3), 0.18 (0.161, 0.201) for HUI(2), 0.11 (0.095, 0.117) for SF-6D, 0.04 (0.039, 0.049) for eQWB, and 0.07 (0.056, 0.077) for VAS (with transformation applied to group means). Conclusion: Differences in preference-weighted health state classification systems are evident at baseline in a population with confirmed IDH, SpS, and DS. Caution should be used when comparing health state values derived from various systems.

Measuring Preferences for Cost-Utility Analysis How Choice of Method May Influence Decision-Making

Preferences for health are required when the economic value of healthcare interventions are assessed within the framework of cost-utility analysis. The objective of this paper was to review alternative methods for preference measurement and to evaluate the extent to which the method may affect healthcare decision-making. Two broad approaches to preference measurement that provide societal health state values were considered: (i) direct measurement; and (ii) preference-based health state classification systems.Among studies that compared alternative preference-based systems, the EQ-5D tended to provide larger change scores and more favourable cost-effectiveness ratios than the Health Utilities Index (HUI)-2 and -3, while the SF-6D provided smaller change scores and less favourable ratios than the other systems. However, these patterns may not hold for all applications. Empirical evidence comparing systems and decision-making impact suggests that preferences will have the greatest impact on economic analyses when chronic conditions or long-term sequelae are involved. At present, there is no clearly superior method, and further study of cost-effectiveness ratios from alternative systems is needed to evaluate system performance.Although there is some evidence that incremental cost-effectiveness ratio (ICER) thresholds (e.g.

Heel Pain—Plantar Fasciitis: Revision 2014

US50 000 per QALY gained) are used in decision-making, they are not strictly applied. Nonetheless, as ICERs rise, the probability of acceptance of a new therapy is likely to decrease, making the differences in QALYs obtained using alternative methods potentially meaningful.It is imperative that those conducting cost-utility analyses characterise the impact that uncertainty in health state values has on the economic value of the interventions studied. Consistent reporting of such analyses would provide further insight into the policy implications of preference measurement.

Predicting SF-6D utility scores from the Oswestry Disability Index and Numeric Rating Scales for Back and Leg Pain

The Orthopaedic Section of the American Physical Therapy Association (APTA) has an ongoing effort to create evidence-based practice guidelines for orthopaedic physical therapy management of patients with musculoskeletal impairments described in the World Health Organizations International Classification of Functioning, Disability, and Health (ICF). The purpose of these revised clinical practice guidelines is to review recent peer-reviewed literature and make recommendations related to nonarthritic heel pain.

The Contribution of Osteoarthritis to Functional Limitations and Disability

Study Design. Cross-sectional cohort. Objective. The purpose of this study is to provide a model to allow estimation of utility from the Short Form (SF)-6D using data from the Oswestry Disability Index (ODI), Back Pain Numeric Rating Scale (BPNRS), and the Leg Pain Numeric Rating Scale (LPNRS). Summary of Background Data. Cost-utility analysis provides important information about the relative value of interventions and requires a measure of utility not often available from clinical trial data. The ODI and numeric rating scales for back (BPNRS) and leg pain (LPNRS), are widely used disease-specific measures for health-related quality of life in patients with lumbar degenerative disorders. The purpose of this study is to provide a model to allow estimation of utility from the SF-6D using data from the ODI, BPNRS, and the LPNRS. Methods. SF-36, ODI, BPNRS, and LPNRS were prospectively collected before surgery, at 12 and 24 months after surgery in 2640 patients undergoing lumbar fusion for degenerative disorders. Spearman correlation coefficients for paired observations from multiple time points between ODI, BPNRS, and LPNRS, and SF-6D utility scores were determined. Regression modeling was done to compute the SF-6D score from the ODI, BPNRS, and LPNRS. Using a separate, independent dataset of 2174 patients in which actual SF-6D and ODI scores were available, the SF-6D was estimated for each subject and compared to their actual SF-6D. Results. In the development sample, the mean age was 52.5 ± 15 years and 34% were male. In the validation sample, the mean age was 52.9 ± 14.2 years and 44% were male. Correlations between the SF-6D and the ODI, BPNRS, and LPNRS were statistically significant (P < 0.0001) with correlation coefficients of 0.82, 0.78, and 0.72, respectively. The regression equation using ODI, BPNRS,and LPNRS to predict SF-6D had an R2 of 0.69 and a root mean square error of 0.076. The model using ODI alone had an R2 of 0.67 and a root mean square error of 0.078. The correlation coefficient between the observed and estimated SF-6D score was 0.80. In the validation analysis, there was no statistically significant difference (P = 0.11) between actual mean SF-6D (0.55 ± 0.12) and the estimated mean SF-6D score (0.55 ± 0.10) using the ODI regression model. Conclusion. This regression-based algorithm may be used to predict SF-6D scores in studies of lumbar degenerative disease that have collected ODI but not utility scores.

Management of Falls in Community-Dwelling Older Adults: Clinical Guidance Statement From the Academy of Geriatric Physical Therapy of the American Physical Therapy Association

This article uses the Disablement Model conceptual framework to guide an analysis of the importance of osteoarthritis (OA) in the development of disability. The Disablement Model describes the development and progression of disablement from impairments to specific functional limitations and disability, and the hypothesized role of predisposing risk factors, extra-individual factors, and intra-individual factors. A wide range of population and clinical studies have characterized the unequivocal contribution of arthritis to the development of functional limitations and disability. Evidence overwhelmingly supports a significant, moderate independent contribution of arthritis to the onset and progression of functional limitations and disability. With respect to important risk factors for the development of functional limitations and disability among those with OA, the evidence provides strong support for the role of physical impairments along with other predisposing and intra-individual factors such as age, body mass index, obesity, lack of exercise, comorbid conditions, depression, and depressive symptoms. Extra-individual factors included need for aids and assistance, and lack of access to public or private transportation. Future disablement research must clarify the causal mechanisms behind a potential risk factors impact on disability and delineate the interplay between and among the various hypothesized steps in the disablement process.

A functional difficulty and functional pain instrument for hip and knee osteoarthritis

Background Falls in older adults are a major public health concern due to high prevalence, impact on health outcomes and quality of life, and treatment costs. Physical therapists can play a major role in reducing fall risk for older adults; however, existing clinical practice guidelines (CPGs) related to fall prevention and management are not targeted to physical therapists. Objective The purpose of this clinical guidance statement (CGS) is to provide recommendations to physical therapists to help improve outcomes in the identification and management of fall risk in community-dwelling older adults. Design and Methods The Subcommittee on Evidence-Based Documents of the Practice Committee of the Academy of Geriatric Physical Therapy developed this CGS. Existing CPGs were identified by systematic search and critically appraised using the Appraisal of Guidelines, Research, and Evaluation in Europe II (AGREE II) tool. Through this process, 3 CPGs were recommended for inclusion in the CGS and were synthesized and summarized. Results Screening recommendations include asking all older adults in contact with a health care provider whether they have fallen in the previous year or have concerns about balance or walking. Follow-up should include screening for balance and mobility impairments. Older adults who screen positive should have a targeted multifactorial assessment and targeted intervention. The components of this assessment and intervention are reviewed in this CGS, and barriers and issues related to implementation are discussed. Limitations A gap analysis supports the need for the development of a physical therapy–specific CPG to provide more precise recommendations for screening and assessment measures, exercise parameters, and delivery models. Conclusion This CGS provides recommendations to assist physical therapists in the identification and management of fall risk in older community-dwelling adults.

Predicting SF-6D utility scores from the Neck Disability Index and Numeric Rating Scales for Neck and Arm Pain

IntroductionThe objectives of this study were to develop a functional outcome instrument for hip and knee osteoarthritis research (OA-FUNCTION-CAT) using item response theory (IRT) and computer adaptive test (CAT) methods and to assess its psychometric performance compared to the current standard in the field.MethodsWe conducted an extensive literature review, focus groups, and cognitive testing to guide the construction of an item bank consisting of 125 functional activities commonly affected by hip and knee osteoarthritis. We recruited a convenience sample of 328 adults with confirmed hip and/or knee osteoarthritis. Subjects reported their degree of functional difficulty and functional pain in performing each activity in the item bank and completed the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Confirmatory factor analyses were conducted to assess scale uni-dimensionality, and IRT methods were used to calibrate the items and examine the fit of the data. We assessed the performance of OA-FUNCTION-CATs of different lengths relative to the full item bank and WOMAC using CAT simulation analyses.ResultsConfirmatory factor analyses revealed distinct functional difficulty and functional pain domains. Descriptive statistics for scores from 5-, 10-, and 15-item CATs were similar to those for the full item bank. The 10-item OA-FUNCTION-CAT scales demonstrated a high degree of accuracy compared with the item bank (r = 0.96 and 0.89, respectively). Compared to the WOMAC, both scales covered a broader score range and demonstrated a higher degree of precision at the ceiling and reliability across the range of scores.ConclusionsThe OA-FUNCTION-CAT provided superior reliability throughout the score range and improved breadth and precision at the ceiling compared with the WOMAC. Further research is needed to assess whether these improvements carry over into superior ability to measure change.

A Longitudinal Comparison of 5 Preference-Weighted Health State Classification Systems in Persons with Intervertebral Disk Herniation

Study Design. Cross-sectional cohort. Objective. This study aims to provide an algorithm to estimate Short Form-6D (SF-6D) utilities using data from the Neck Disability Index (NDI), neck pain, and arm pain scores. Summary of Background Data. Although cost-utility analysis is increasingly used to provide information about the relative value of alternative interventions, health state values or utilities are rarely available from clinical trial data. The Neck Disability Index (NDI) and numerical rating scales for neck and arm pain are widely used diseasespecific measures in patients with cervical degenerative disorders. The purpose of this study is to provide an algorithm to allow estimation of SF-6D utilities using data from the NDI, and numerical rating scales for neck and arm pain. Methods. SF-36, NDI, neck and arm pain rating scale scores were prospectively collected before surgery, at 12 and 24 months after surgery in 2080 patients undergoing cervical fusion for degenerative disorders. SF-6D utilities were computed, and Spearman correlation coefficients were calculated for paired observations from multiple time points between NDI, neck and arm pain scores, and SF-6D utility scores. SF-6D scores were estimated from the NDI, neck and arm pain scores were estimated using a linear regression model. Using a separate, independent dataset of 396 patients in which NDI scores were available, SF-6D was estimated for each subject and compared to their actual SF-6D. Results. The mean age for those in the development sample was 50.4 ± 11.0 years and 33% were male. In the validation sample, the mean age was 53.1 ± 9.9 years and 35% were male. Correlations between the SF-6D and the NDI, neck and arm pain scores were statistically significant (P < 0.0001) with correlation coefficients of 0.82, 0.62, and 0.50, respectively. The regression equation using NDI aloneto predict SF-6D had an R2 of 0.66 and a root mean square error of 0.056. In the validation analysis, there was no statistically significant difference (P = 0.961) between actual mean SF-6D (0.49 ± 0.08) and the estimated mean SF-6D score (0.49 ± 0.08), using the NDI regression model. Conclusion. This regression-based algorithm may be a useful tool to predict SF-6D scores in studies of cervical degenerative disease that have collected NDI but not utility scores.

Clinical outcomes assessment in clinical trials to assess treatment of femoroacetabular impingement: use of patient-reported outcome measures.

Objective. To assess the longitudinal validity of widely used preference-weighted measurement systems for economic studies of intervertebral disk herniation (IDH). Methods. Using data at baseline and 1 year from 1000 Spine Patient Outcomes Research Trial (SPORT) participants with IDH and complete data, the authors considered the EQ-5D with UK and US values (EQ-5D-UK and EQ-5D-US), 2 versions of the Health Utilities Index (HUI3 and HUI2), the SF-6D, and a regression-estimated quality of well-being score (eQWB). Differences in mean change scores (MCS) were assessed using signed rank tests, and Spearman correlations were calculated for change scores by system pairs. Using the Oswestry Disability Index, symptom satisfaction, progress rating, and self-perceived health ratings as criterion measures, the authors tested for trend in MCS across levels of change in criteria. They calculated floor and ceiling effects, effect size (ES), standardized response mean, and minimal important difference estimates. Results. All systems demonstrated linear trends with external criteria and moderate to strong correlations between systems. However, differences in performance were evident. SF-6D and eQWB were most responsive (ES: 1.9 and 2.3, respectively), whereas EQ-5D-US and EQ-5D-UK were least responsive (ES: 1.23/1.20). Ceiling and floor effects were noted for all systems within key dimensions and for EQ-5D-UK and EQ-5D-US for overall score. MCS ranged from 0.40 (0.38) for EQ-5D-UK to 0.13 (0.09) for eQWB and differed significantly, except between EQ-5D-US and HUI2. Conclusions. This research supports the validity of all systems for measuring change in persons with IDH, without finding a clearly superior system. The unique characteristics of each system revealed in this study should guide system choice.