Is the Health Utilities Index responsive in total hip arthroplasty patients?

OBJECTIVE: The purpose is to examine the responsiveness of the Health Utilities Index Mark 2 (HUI2), Mark 3 (HUI3), and other generic and disease-specific measures in osteoarthritis patients undergoing total hip arthroplasty (THA). METHODS: Ninety patients (mean age=68.13; SD=8.15) on a waiting list for THA completed measures that included the standard gamble, HUI2, HUI3, SF-36, Harris Hip Scale, WOMAC, and MACTAR. before and after THA. Responsiveness statistics (effect size, standardized response mean, Guyatt's responsiveness statistic, paired-sample t-tests, and relative efficiency statistic) were calculated. RESULTS: The disease-specific measures were more responsive than the generic measures. Rankings of the degree of responsiveness varied depending on the responsiveness statistic used. CONCLUSIONS: Disease-specific measures are the most responsive in THA patients. However, the SF-36, HUI2, and HUI3 had summary scores and domain/attributes scores that were also responsive and provided additional information. Among the generic measures, HUI3 was the most responsive.     

Comparing the Health Utilities Index Mark 3 (HUI3) with the Short Form-36 Preference-Based SF-6D in Chronic Kidney Disease

Objective:  Assess within-subject agreement and compare discriminative abilities between the SF-6D and the Health Utilities Index Mark 3 (HUI3) in patients with chronic kidney disease (CKD).
Methods:  The HUI3 and Short Form-36 were self-completed by 185 CKD patients enrolled in a prospective study of incident patients with stage 4 and 5 CKD.
Results:  The mean preference-based score for the SF-6D was 0.67 ± 0.13 compared to 0.58 ± 0.26 for the HUI3 ( P  < 0.01). There was a strong association between SF-6D and HUI3 scores (Pearson correlation coefficient 0.55, 95% CI 0.43–0.65) and moderate agreement with an intraclass correlation coefficient of 0.44. The HUI3 was better able to capture more severe burden of illness with fewer floor effects. The SF-6D was better at capturing differences among patients at the top range of the scale with fewer ceiling effects. Both the HUI3 and SF-6D were able to discriminate between patient groups differing in disease severity defined as predialysis versus dialysis dependent and depressive symptoms using a Beck Depression Inventory II score of ≥14 as the cutoff. The HUI3 was better able to discriminate greater depressive symptoms.
Conclusion:  The SF-6D and the HUI3 generate different preference-based scores for patients with CKD and any comparison between their scores should be made with caution. The HUI3 appears more suitable for measuring the health of populations with greater disability such as patients with CKD. It remains to be determined whether these differences will remain when one compares within-instrument differences in preference scores over time.     

Comparing short form and RAND physical and mental health summary scores: results from total hip arthroplasty and high-risk primary-care patients

OBJECTIVES: Summary physical health scores for the Short Form (SF) measures are computing using positive weights for physical items and negative weights for mental health items. Mental health summary scores use positive weights for mental items and negative weights for physical. The RAND Health Status Inventory (HSI) measures do not use negative weights. Do these different approaches to scoring matter? The objective was to compare summary scores using both the SF and RAND-HSI. METHODS: SF-36 and the Health Utilities Index Mark 3 (HUI3) were administered to a cohort of patients waiting for elective total hip arthroplasty (THA). SF-12 and HUI3 were administered to a cohort of high-risk primary-care patients. Summary scores were generated and compared. Single-attribute utility scores for emotion in HUI3 were also computed. Canadian and US norms for SF, RAND-HSI, and HUI3 were used to interpret results. RESULTS: For THA patients, mean physical health scores were 28 and 36 for SF and RAND-HSI. Mean mental health scores were 55 and 42. For the primary-care patients, the scores were 34 and 36 for physical and 46 and 40 for mental health. CONCLUSIONS: SF and RAND-HSI provided somewhat similar summary scores in the THA study. However, SF and RAND-HSI mental health scores differed in the primary-care patient cohort and results from HUI3 corroborate the mental health deficits identified by the RAND-HSI. It may be wise for investigators to use both SF and RAND-HSI scoring systems.     

Comparison of preference-based utilities of the Short-Form 36 Health Survey and Health Utilities Index before and after treatment of patients with intermittent claudication.

The authors compared SF-36 utilities with Health Utilities Index (HUI) utilities (HUI2 and HUI3) assessed in patients with intermittent claudication. A total of 87 patients with intermittent claudication completed the SF-36 and HUI before and 1, 3, and 12 months after revascularization. Utilities were estimated using SF-36 and HUI published algorithms (i.e., both algorithms were based on standard-gamble utilities assessed in random samples of the general population). The utilities were compared using repeated-measures multivariate analysis of variance, paired t tests, and univariate linear regression analyses. Before treatment, the mean SF-36 and HUI3 utilities were the same (0.66 vs. 0.66, P = 0.92) and less than the mean HUI2 utility (0.70, P = 0.02). After treatment, all utilities showed improvement from before treatment (P < 0.05); the gain in utilities from treatment was lowest when using the SF-36 (e.g., 0.74, 0.80, 0.77 at 3 months for the SF-36, HUI2, and HUI3, respectively). The correlations of changes over time of the SF-36 with HUI2 utilities and of the SF-36 with HUI3 utilities were 0.39 and 0.49, respectively. The relationships between the SF-36 and HUI2 or HUI3 utilities were moderate to good (i.e., range-adjusted R2 = 31% to 72%). The results suggest that SF-36 data can be transformed to preference-based utilities and be used for economic evaluation in health care. The gain in utilities from treatment, however, was less for SF-36 utilities than for HUI utilities.     

Comparing Short Form 6D,Standard Gamble,and Health Utilities Index Mark 2 and Mark 3 utility scores: Results from total hip arthroplasty patients

Objective: The objectives are to compare SF-6D, standard gamble (SG), and Health Utilities Index (HUI) utility scores, compare change scores, and compare responsiveness. Methods: A cohort of osteoarthritis patients referred for total hip arthroplasty (THA) were evaluated at the time of referral and followed until 3months after THA. Patients were assessed using the SF-36, HUI2, HUI3, and the SG. Agreement is assessed using the intra-class correlation (ICC). Responsiveness is assessed using effect size, standardized response mean, and paired t-test. Results: Data was available for 86 patients at baseline and for 63 at both pre- and post-surgery. At baseline mean SF-6D (0.61), SG (0.62), and HUI2 (0.62) scores were similar; the mean HUI3 score (0.52) was lower. Standard deviations were 0.10, 0.32, 0.19, and 0.22. At baseline, agreement between SF-6D and SG scores was 0.13, agreement between SF-6D and HUI2 was 0.47, and agreement between SF-6D and HUI3 was 0.28. Agreement at pre- and post-surgery was similar. The change in scores between post- and pre-surgery was 0.10 for SF-6D, 0.16 for SG, 0.22 for HUI2, and 0.23 for HUI3. Effect sizes were 1.10 for HUI2, 1.08 for HUI3, 1.06 for SF-6D, and 0.48 for the SG. Conclusions: Agreement between SG scores and SF-6D and HUI scores was low. The estimate of change in utility associated with THA was lowest for SF-6D. Additional longitudinal studies to compare utility measures appear to be warranted.     

A view from the bridge: agreement between the SF-6D utility algorithm and the Health Utilities Index

BACKGROUND: The SF-6D is a new health state classification and utility scoring system based on 6 dimensions ('6D') of the Short Form 36, and permits a "bridging" transformation between SF-36 responses and utilities. The Health Utilities Index, mark 3 (HUI3) is a valid and reliable multi-attribute health utility scale that is widely used. We assessed within-subject agreement between SF-6D utilities and those from HUI3. METHODS: Patients at increased risk of sudden cardiac death and participating in a randomized trial of implantable defibrillator therapy completed both instruments at baseline. Score distributions were inspected by scatterplot and histogram and mean score differences compared by paired t-test. Pearson correlation was computed between instrument scores and also between dimension scores within instruments. Between-instrument agreement was by intra-class correlation coefficient (ICC). RESULTS: SF-6D and HUI3 forms were available from 246 patients. Mean scores for HUI3 and SF-6D were 0.61 (95% CI 0.60-0.63) and 0.58 (95% CI 0.54-0.62) respectively; a difference of 0.03 (p<0.03). Score intervals for HUI3 and SF-6D were (-0.21 to 1.0) and (0.30-0.95). Correlation between the instrument scores was 0.58 (95% CI 0.48-0.68) and agreement by ICC was 0.42 (95% CI 0.31-0.52). Correlations between dimensions of SF-6D were higher than for HUI3. CONCLUSIONS: Our study casts doubt on the whether utilities and QALYs estimated via SF-6D are comparable with those from HUI3. Utility differences may be due to differences in underlying concepts of health being measured, or different measurement approaches, or both. No gold standard exists for utility measurement and the SF-6D is a valuable addition that permits SF-36 data to be transformed into utilities to estimate QALYs. The challenge is developing a better understanding as to why these classification-based utility instruments differ so markedly in their distributions and point estimates of derived utilities.     

Comparison of the SF-36 health survey questionnaire with the Nottingham Health Profile in long-term survivors of a myocardial infarction

BACKGROUND: Health-related quality of life, an important outcome measure in health interventions, can readily be assessed by questionnaire. Two widely evaluated examples are the Short Form 36 (SF-36) and Nottingham Health Profile (NHP) questionnaires, but as yet the discriminatory power of these tools has not been compared in a large population of patients with coronary heart disease. METHODS: All 4-year survivors of a myocardial infarction, identified from the Nottingham heart attack register, were sent the SF-36, NHP and additionally the Rose angina and dyspnoea questionnaires. Mean scores on the SF-36 and NHP were compared with age- and sex-adjusted norms in patients under and over 65 years. Sensitivity of the respective tools was assessed in distinguishing patients with differing degrees of cardiovascular symptomatology. RESULTS: In patients under 65 years the SF-36 and NHP differed to the same extent from normative data--scores were lower in the comparable domains physical functioning/mobility, bodily pain/pain and energy/vitality, but not in mental health/emotional reaction scores. In social functioning/social isolation results were disparate--SF-36 scores were lower and the NHP similar to normative data. In patients over 65 years mean scores in all five domains were not significantly different from normative data for either tool. The SF-36 was more sensitive than the NHP at detecting the impact of breathlessness, particularly in patients with mild symptoms. Similarly, the SF-36, but not the NHP, could distinguish the effect of differing degrees of angina severity and frequency on social functioning. CONCLUSION: At least in myocardial infarction survivors, the SF-36 appears a more sensitive tool and may have benefits for assessing health-related quality of life in this patient group.     

A Study of the Construct Validity of the Health Utilities Index Mark 3 (HUI3) in Patients with Schizophrenia

This study assessed the construct validity of the Health Utilities Index Mark 3 (HUI3) in patients with schizophrenia. Patients with schizophrenia recruited from a tertiary mental hospital in Singapore completed the HUI3, the Short-Form 36 Health Survey (SF-36) and the Schizophrenia Quality of Life Scale (SQLS). Patients were assessed for presence and absence of 22 common psychiatric symptoms. Construct validity was assessed using 6 a priori hypotheses. Two hundred and two patients (mean age: 37.8 years, female: 52%) completed the survey. As hypothesized, overall HUI3 utility scores were correlated with SF-36 measures (Spearman’s rho: 0.19 to 0.51), SQLS scales (Spearman’s rho: −0.56 to −0.36), and the number of psychiatric symptoms (Spearman’s rho: −0.49). The HUI3 emotion attribute was moderately correlated with SF-36 mental health (Spearman’s rho: 0.45) and SQLS psychosocial scales (Spearman’s rho: −0.43), and HUI3 pain attribute was strongly correlated with SF-36 bodily pain scale (Spearman’s rho: 0.58). The mean HUI3 overall, emotion, cognition, and speech scores for patients with schizophrenia were 0.07, 0.09, 0.04 and 0.04 points lower than respective age-, sex- and ethnicity-adjusted population norms (p<0.001 for all, ANCOVA). This study provides evidence for the construct validity of the HUI3 in patients with schizophrenia.     

Responsiveness of generic health-related quality of life measures in stroke

Objective: To compare five preference-based generic measures of health-related quality of life (HRQOL) in terms of change scores, correlations among change scores, responsiveness, and quality adjusted life-years (QALYs) gained. Design: Observational longitudinal cohort study where clinical measures and self-assessed HRQOL measures were administered to stroke patients at baseline and at 6 months. Patients were categorized as ‘stable’, ‘some improvement’ and ‘large improvement’ using the Barthel Index, Modified Rankin Scale (MRS), and Center for Epidemiologic Studies Depression Scale (CES-D). For each group, paired t -tests and variants of effect size were used to compare the responsiveness of preference-based HRQOL summary scores, including the EQ-5D VAS and index-based score, SF-6D, and Health Utilities Index (HUI) Mark 2 (HUI2) and Mark 3 (HUI3) overall utility scores. Results: Ninety-eight of 124 (79%) patients completed the 6-month follow-up. Change scores of the EQ-Index, HUI2, and HUI3 were strongly correlated with changes in the Barthel Index and MRS, while the EQ-5D VAS had higher correlation with CES-D change scores than the other measures. The SF-6D, HUI3, and EQ-Index were generally more responsive than the HUI2 and EQ-5D Visual analogue scale (EQ-VAS). QALY estimates based on the EQ-5D index and HUI3 were twice as large as estimates based on the SF-6D and HUI2. Conclusions : The results of this study may assist in informing the selection of a preference-based generic HRQOL measure, although choice will also depend on study goals and context. We would caution against the generalization of the study results on responsiveness to conditions when more subtle change is expected.     

MGA5 Health Utilities Index: Further Evidence of Responsiveness

Quality adjusted life years (QALYs) are well recognized as a valid measure for outcomes in cost-effectiveness analyses. However, it is difficult to obtain a summary utility score from health status measure such as the SF-36.
OBJECTIVE: To predict a summary utility score (represented by HUI) from the scores on the SF-36.
METHODS: A structural equation framework was applied to data collected from 1992 to 1995 on the Southern California Kaiser Permanente population (n = 5,794). An instrumental variable (IV) method mitigated the endogeneity in estimating the HUI(MarkII). Socioeconomic and disease variables were used as covariates. A split-sample analysis provided cross-validation.
RESULT: This model predicted 33.68% of the observed variance in HUI index scores with an adjusted R²of 0.3335. Observed HUI index scores were distributed with a mean of 0.7963 and std. deviation of 0.1796. Parameter estimates of most of the SF-36 components (except General Health & Social Functioning) showed statistical significance at α= 0.05 level. People with high chronic disease scores were found to have low SF-36 scores, and parameter estimates of this covariate were also found statistically significant at α= 0.05 level in all structural equations. However, all the socioeconomic variables showed statistical insignificance. Comparison of "Forecasting" and "Estimation" sub-samples showed satisfactory results during cross-validation.
CONCLUSION: Result of this study provides a quantitative link between two important measures of health status. The present model can be used to estimate overall health utility summary scores from previous studies using the SF-36.     

Evaluating quality-adjusted life years: estimation of the health utility index (HUI2) from the SF-36.

Quality-adjusted life years (QALYs) are well recognized as a valid measure for outcomes in cost-effectiveness analyses. A summary health utility score is necessary to evaluate QALYs. The objective of this study was to predict a summary utility score (represented by the Health Utility Index [HUI2]) from scores on the SF-36. METHODS: A structural equation framework was applied to longitudinal data collected from 1992 to 1995 on a sample of patients insured by Southem California Kaiser Permanente (N = 6921). An ordinary least squares (OLS) method was used to estimate the HUI2. RESULTS: The OLS model on cross-sectional data predicted 50.5% of the observed variance in HUI2 scores. Parameter estimates of all SF-36 components showed statistical significance at the P < 0.05 level. CONCLUSIONS: Results of this study provide a quantitative link between two important measures of health status. The present model can be used to estimate health utility summary scores in studies that have collected SF-36 data.     

Comparison of measures to assess outcomes in total hip replacement surgery.

OBJECTIVES--To compare the performance of a disease specific and a general health questionnaire in assessing changes resulting from total hip replacement. DESIGN--Two stage prospective study of patients undergoing total hip replacement surgery involving an assessment at a clinic before and six months after surgery. 60(32%) patients were followed up by post. SETTING--Outpatient departments at a specialist orthopaedic hospital and peripheral clinics within Oxfordshire. PATIENTS--188 patients admitted for unilateral total hip replacement between February and mid-August 1994. MAIN MEASURES--Patients' self assessed scores with the 12 item Oxford hip score and SF-36 general health questionnaire together with surgeons' assessment with Charnley hip score obtained before and again at six months after surgery. RESULTS--186 patients were followed up six months after total hip replacement; a subsample (n=60) by post. Of the 60 postal patients, 59(98.3%) fully completed the Oxford hip score compared with 44(73.3%) who fully completed the SF-36. For the followup sample as a whole, post operative changes in scores produced a large effect size of 2.75 on the Oxford hip score, compared with -1.89 physical function (SF-36), -2.13 pain (SF-36). With the exception of physical function and role (physical), postoperative SF-36 scores were shown to be similar to or better than those found by two population surveys on patients of comparable age. The responsiveness of a disease specific questionnaire, the Oxford hip score, and relevant sections of a general questionnaire, SF-36, were found to be similar as assessed by three different criteria. CONCLUSIONS--A disease specific questionnaire, the Oxford hip score, and a general state of health questionnaire, SF-36, performed similarly in assessing outcomes of total hip replacement except that the disease specific questionnaire resulted in a higher completion rate and greater responsiveness in some sections. On the other hand the general health questionnaire drew attention to broader problems of physical function not considered by the Oxford hip score. The health questionnaires examined here offer a valid and practical means of monitoring outcomes of hip replacement surgery.     

A cohort study found the RAND-12 and Health Utilities Index Mark 3 demonstrated construct validity in high-risk primary care patients

OBJECTIVE: The Short Form 12 (SF-12) is widely used in primary care settings. The RAND-12 Health Status Inventory (HSI) and the Health Utilities Index Mark 3 (HUI3) have not been as widely used in such settings. The objective of this study was to examine the construct validity of the RAND-12 and HUI3 in the context of high-risk primary care patients. STUDY DESIGN AND SETTING: The SF-12, HUI2, and HUI3 were administered to a cohort of high-risk primary care patients. RAND-12 summary scores for physical and mental health were generated. Single-attribute utility scores for each dimension of health status and overall health in HUI3 were computed. A priori hypotheses were specified. RESULTS: In general, the relationships among RAND-12 and HUI3 scores were consistent with construct validity. Twelve of 24 a priori predictions were confirmed. However, predictions about the correlations between the number of medical conditions and the number of medications and the measures of health-related quality of life were, in general, not confirmed. CONCLUSIONS: The RAND-12 and HUI3 seem to be useful among primary care patients with diverse chronic conditions. Further investigation is warranted.     

Effects of Mode and Order of Administration on Generic Health-Related Quality of Life Scores

ObjectiveWe evaluate the effects of mode and order of administration on health-related quality of life (HRQOL) scores.MethodWe analyzed HRQOL data from the Clinical Outcomes and Measurement of Health Study (COMHS). In COMHS, we enrolled patients with heart failure or cataracts at three sites (University of California, San Diego, University of California, Los Angeles, and University of Wisconsin). Patients completed self-administered HRQOL instruments at baseline and months 1 and 6 post-baseline, including the EuroQol (EQ-5D), Health Utilities Index (HUI), Quality of Well-Being Scale—self-administered (QWB-SA), and the Short Form (SF)-36v2. At the 6 months follow-up, individuals were randomized to mail or telephone administration first, followed by the other mode of administration. We used repeated measures mixed effects models, adjusting for site, patient age, education, gender, and race.ResultsIncluded were 121 individuals entering a heart failure program and 326 individuals scheduled for cataract surgery who completed the survey by mail or phone at the 6-month follow-up. The majority of the sample was female (53%) and white (86%). About a quarter of the sample had high school education or less (26%). The average age was 66 (36–91 range). HRQOL scores were higher (more positive) for phone administration following mail administration. The largest differences in scores between phone and mail responses occurred for comparisons of telephone responses for those who were randomized to a mail survey first compared with mail responses for those randomized to a telephone survey first (i.e., mode effects for responses that were given on the second administration of the HRQOL measures). The QWB-SA was the only measure that did not display the pattern of mode effects. The biggest differences between modes were 4 points on the SF-36v2 physical health and mental health component summary scores, 0.06 on the SF-6D, 0.03 on the QWB-SA, 0.08 on the EQ-5D, 0.04 on the HUI2, and 0.10 on the HUI3.ConclusionsTelephone administration yields significantly more positive HRQOL scores for all of the generic HRQOL measures except for the QWB-SA. The magnitude of effects was clearly important, with some differences as large as a half-standard deviation. These findings confirm the importance of considering mode of administration when interpreting HRQOL scores.     

Five preference-based indexes in cataract and heart failure patients were not equally responsive to change

Objective

To compare the responsiveness to clinical change of five widely used preference-based health-related quality-of-life indexes in two longitudinal cohorts.

Study Design and Setting

Five generic instruments were simultaneously administered to 376 adults undergoing cataract surgery and 160 adults in heart failure management programs. Patients were assessed at baseline and reevaluated after 1 and 6 months. The measures were the Short Form (SF)-6D (based on responses scored from SF-36v2), Self-Administered Quality of Well-being Scale (QWB-SA), the EuroQol-5D developed by the EuroQol Group, the Health Utilities Indexes Mark 2 (HUI2) and Mark 3 (HUI3). Cataract patients completed the National Eye Institute Visual Functioning Questionnaire-25, and heart failure patients completed the Minnesota Living with Heart Failure Questionnaire. Responsiveness was estimated by the standardized response mean.

Results

For cataract patients, mean changes between baseline and 1-month follow-up for the generic indices ranged from 0.00 (SF-6D) to 0.052 (HUI3) and were statistically significant for all indexes except the SF-6D. For heart failure patients, only the SF-6D showed significant change from baseline to 1 month, whereas only the QWB-SA change was significant between 1 and 6 months.

Conclusions

Preference-based methods for measuring health outcomes are not equally responsive to change.     

The effect of weight loss on changes in health-related quality of life among overweight and obese women with urinary incontinence

Objective

To estimate the effect of change in weight and change in urinary incontinence (UI) frequency on changes in preference-based measures of health-related quality of life (HRQL) among overweight and obese women with UI participating in a weight loss trial.

Methods

We conducted a longitudinal cohort analysis of 338 overweight and obese women with UI enrolled in a randomized clinical trial comparing a behavioral weight loss intervention to an educational control condition. At baseline, 6, and 18?months, health utilities were estimated using the Health Utilities Index Mark 3 (HUI3), a transformation of the SF-36 to the preference-based SF-6D, and the estimated Quality of Well-Being (eQWB) score (a summary calculated from the SF-36 physical functioning, mental health, bodily pain, general health perceptions, and role limitations?Cphysical subscale scores). Potential predictors of changes in these outcomes were examined using generalized estimating equations.

Results

In adjusted multivariable models, weight loss was associated with improvement in HUI3, SF-6D, and eQWB at 6 and 18?months (P?<?0.05). Increases in physical activity also were independently associated with improvement in HUI3 (P?=?0.01) and SF-6D (P?=?0.006) scores at 18?months. In contrast, reduction in UI frequency did not predict improvements in HRQL at 6 or 18?months.

Conclusion

Weight loss and increased physical activity, but not reduction in UI frequency, were strongly associated with improvements in health utilities measured by the HUI3, SF-6D, and eQWB. These findings provide important information that can be used to inform cost?Cutility analyses of weight loss interventions.     

Comparing directly measured standard gamble scores to HUI2 and HUI3 utility scores: group- and individual-level comparisons

Directly measured standard gamble (SG) utility scores reflect the respondent's assessment and valuation of their own health status. Scores from the health utilities index (HUI) are based on self-assessed health status but valued using community preferences obtained using the SG. Our objectives were to find if mean directly measured utility scores agree with mean HUI mark 2 (HUI2) and mean HUI mark 3 (HUI3) scores. Also, if individual directly measured utility scores agree with HUI2 and HUI3 scores, and whether HUI2 and HUI3 scores agree. Questionnaires based on the HUI2 and HUI3 health-status classification systems were administered by interviewers to 140 teenage survivors of extremely low birthweight (ELBW) and 124 control group teens. Respondents were asked to think about their own usual health states using six dimensions from HUI2 and value that state using the SG. Mean SG scores are compared with mean HUI2 and mean HUI3 scores using paired sample t-tests. Mean HUI2 scores are compared with mean HUI3 scores. Agreement among scores is assessed using intra-class correlation coefficient (ICC). The effect of severity of health-state morbidity on agreement was assessed using three approaches. ELBW cohort mean (standard deviation) SG, HUI2, and HUI3 scores were 0.90 (0.20), 0.89 (0.14), and 0.80 (0.22). Results for controls were 0.93 (0.11), 0.95 (0.09), and 0.89 (0.13). Mean SG and HUI2 scores did not differ; mean SG and HUI3 did differ; mean HUI2 and HUI3 also differed. At the individual level for ELBW, the ICCs between SG and HUI2, SG and HUI3, and HUI2 and HUI3 scores were 0.13, 0.28, and 0.64. For controls the ICCs were 0.14, 0.24, and 0.56. HUI2 scores appear to match directly measured utility scores reasonably well at the group level. HUI2 and HUI3 scores differ systematically. At the individual level, however, HUI2 and HUI3 scores are poor substitutes for directly measured scores.     

Relationship between health status and utility measures in older claudicants

The purpose of this study was to examine the relationship between health status and health utility measures in 34 older claudicants and to determine which attributes of health status were significant predictors of health state valuation/preference. The MOS SF-36 was used to assess health status and the rating scale and multiattribute Health Utility Index (HUI) were used to assess utility scores. With regard to health status, the bodily pain and physical functioning subscales contributed the most to reductions in quality of life (QoL) with mean subscale scores substantially lower than reported population norms. Patients rated their health status approximately one-third below a state of perfect health on both utility measures. Moderate correlations were observed between the MOS SF-36 subscale scores and the HUI and rating scale scores. In multivariable regression models, physical functioning and mental health were the best predictors of HUI scores, whereas general health and vitality were the best predictors of rating scale scores. Approximately 50% of the variance in utility scores was explained by these attributes. This study provides further documentation that bodily pain and reductions in physical function contribute to reductions in QoL in older patients with intermittent claudication. Other attributes of health status, however, notably psychological distress, were predictive of patients' preference for health states. Recognized constructs of physical and mental health explained the substantial variation in the utility/preference assessment in this population. Furthermore, these data are consistent with those reported in the Dutch Iliac Stent Trial.