Optimizing the Implementation of Clinical Predictive Models to Minimize National Costs: Sepsis Case Study

BACKGROUND

Sepsis costs and incidence vary dramatically across diagnostic categories, warranting a customized approach for implementing predictive models.

OBJECTIVE

The aim of this study was to optimize the parameters of a sepsis prediction model within distinct patient groups to minimize the excess cost of sepsis care and analyze the potential effect of factors contributing to end-user response to sepsis alerts on overall model utility.

METHODS

We calculated the excess costs of sepsis to the Centers for Medicare and Medicaid Services (CMS) by comparing patients with and without a secondary sepsis diagnosis but with the same primary diagnosis and baseline comorbidities. We optimized the parameters of a sepsis prediction algorithm across different diagnostic categories to minimize these excess costs. At the optima, we evaluated diagnostic odds ratios and analyzed the impact of compliance factors such as noncompliance, treatment efficacy, and tolerance for false alarms on the net benefit of triggering sepsis alerts.

RESULTS

Compliance factors significantly contributed to the net benefit of triggering a sepsis alert. However, a customized deployment policy can achieve a significantly higher diagnostic odds ratio and reduced costs of sepsis care. Implementing our optimization routine with powerful predictive models could result in US $4.6 billion in excess cost savings for CMS.

CONCLUSIONS

We designed a framework for customizing sepsis alert protocols within different diagnostic categories to minimize excess costs and analyzed model performance as a function of false alarm tolerance and compliance with model recommendations. We provide a framework that CMS policymakers could use to recommend minimum adherence rates to the early recognition and appropriate care of sepsis that is sensitive to hospital department-level incidence rates and national excess costs. Customizing the implementation of clinical predictive models by accounting for various behavioral and economic factors may improve the practical benefit of predictive models.

Vignette-Based Utilities: Usefulness, Limitations, and Methodological Recommendations

Health technology assessment agencies often prefer that utilities used to calculate quality-adjusted life years in cost-utility analyses (CUAs) are derived using standardized methods, such as generic preference-based measures completed by patients in clinical trials. However, there are situations when no standardized approach is feasible or appropriate for a specific medical condition or treatment that must be represented in a CUA. When this occurs, vignette-based methods are often used to estimate utilities. A vignette (sometimes called a "scenario," "health state description," "health state vignette," or "health state") is a description of a health state that is valued in a preference elicitation task to obtain a utility estimate. This method is sometimes the only feasible way to estimate utilities representing a concept that is important for a CUA. Consequently, vignette-based studies continue to be conducted and published, with the resulting utilities used in economic models to inform decision making about healthcare resource allocation. Despite the potential impact of vignette-based utilities on medical decision making, there is no published guidance or review of this methodology. This article provides recommendations for researchers, health technology assessment reviewers, and policymakers who may be deciding whether to use vignette-based methods, designing a vignette study, using vignette-based utilities in a CUA, or evaluating a CUA that includes vignette-based utilities. Recommendations are provided on: (A) when to use vignette-based utilities, (B) methods for developing vignettes, (C) valuing vignettes, (D) use of vignette-based utilities in models, and (E) limitations of vignette methods.

Peruvian Valuation of the EQ-5D-5L: A Direct Comparison of Time Trade-Off and Discrete Choice Experiments

OBJECTIVES

(1) To produce Peruvian general population EQ-5D-5L value sets on a quality-adjusted life-year scale, (2) to investigate the feasibility of a "Lite" protocol less reliant on the composite time trade-off (cTTO), and (3) to compare cTTO and discrete choice experiment (DCE) value sets.

METHODS

A random sample of adults (N = 1000) in Lima, Arequipa, and Iquitos did a home interview; 300 were randomly selected to complete 11 cTTOs first. All respondents completed a DCE, including 10 latent-scale pairs (A/B) with 5 EQ-5D-5L attributes, and 12 matched pairs (A/B and B/C) with 5 EQ-5D-5L and one lifespan attributes. We estimated a cTTO heteroscedastic tobit (N = 300) model and 3 DCE Zermelo-Bradley-Terry models (N = 300, 700, and 1000).

RESULTS

Each model produced a consistent value set (20 positive incremental parameters). Nevertheless, their lowest quality-adjusted life-year values differed greatly (cTTO: -1.076 [N = 300]; DCE: -0.984 [300], 0.048 [700], -0.213 [1000]). Compared with the cTTO, the DCE (N = 300) produced different parameters (Pearson's correlation = 0.541), fewer insignificant parameters (0 vs 8), and fewer values less than 0 (26% vs 44%). Compared with the DCE (N = 300), the DCE (N = 700) produced higher values but similar parameters (Pearson's correlation = 0.800).

CONCLUSIONS

Besides producing EQ-5D-5L value sets for Peru, the results casts doubt about the feasibility of a Lite protocol like the one in this study. Additionally, fundamental differences between cTTO and DCE-without the existence of a gold standard-need further clarification. The choice between the two rational value sets produced in the current study is a matter of judgment and may have substantial policy implications.

Analysis of Utility Assessment Scores to Objectify the Health Burden Caused by Breast Conservation Therapy

Background

Lumpectomy followed by radiation, known as breast conservation therapy (BCT), is a viable surgical treatment option for early-stage breast cancer. However, the current literature suggests that patients prefer mastectomy over BCT, likely due to the wide variety of postmastectomy reconstructive options. Our aim is to investigate the objective health burden of living with BCT to help surgeons gain a better understanding of patient treatment preferences.

Methods

Three validated health state utility tools were used to objectify the burden of living with post-BCT results: visual analogue scale (VAS), time trade-off (TTO), and standard gamble (SG). A prospective sample of the general population and medical students were recruited, and their responses analyzed to attain these scores.

Results

Utility scores for living with BCT are VAS 0.81 ± 0.19, TTO 0.93 ± 0.10, and SG 0.92 ± 0.14. The TTO and SG suggest a willingness to trade 2.5 years of life years and an 8% chance of death undergoing reconstructive procedures to correct a BCT defect, respectively. Age, gender, race, education, and income were not statistically significant independent predictors for higher or lower utility scores.

Conclusion

The impact of the health burden of BCT was ascertained using validated objective numeric utility scores. These indices demonstrate a willingness to trade less life years to undergo correction of a BCT defect than reconstruction following unilateral mastectomy. They can provide surgeons with the best objective understanding of patient preferences for shared decision-making in the management of breast cancer.

What Difference Does It Make? A Comparison of Health State Preferences Elicited From the General Population and From People With Multiple Sclerosis

BACKGROUND

A major debate in the quality-adjusted life-year (QALY) literature concerns whose preferences should be used to estimate health state values (HSVs) and to calculate QALYs.

OBJECTIVES

This study explores differences between public and patient values for multiple sclerosis (MS) health states, described using an MS-specific classification system (Multiple Sclerosis Impact Scale-8 Dimensions [MSIS-8D]).

METHODS

The MSIS-8D is an existing preference-based measure of health-related quality of life in MS, which has 2 tariffs of HSVs, based on the preferences of a representative sample of the UK general population (n = 1702) and of people with MS living in the United Kingdom (n = 1635), elicited using the time trade-off technique. Here, we explore differences between HSVs by sample type, using descriptive statistics and multivariate regression methods.

RESULTS

Overall, the survey of people with MS produced significantly higher HSVs; estimated values ranged from 0.079 to 0.883 for the general population survey and from 0.138 to 0.894 for the MS survey. Differences in HSVs were more pronounced for severe health states. The difference between patient and public values varied across the dimensions of the MSIS-8D. People with MS placed greater importance on cognition than the general population, leading to lower HSVs when impairment was at a worse level; the reverse was true for the daily activities, fatigue, and depression dimensions.

CONCLUSIONS

We identified significant differences in HSVs by sample type. Using patient rather than public values may influence the results of economic evaluations, depending on the dimensions of health-related quality of life affected by the intervention being assessed, and may therefore have important consequences for reimbursement decisions.

Comparison of Rating Scale, Time Tradeoff, and Conjoint Analysis Methods for Assessment of Preferences in Prostate Cancer

Background. Conjoint analysis is widely used in studies of consumer preference but has only recently been applied to measure patient utilities for health outcomes. We compared the reliability, feasibility, and internal and predictive validity of conjoint scaling methods against better established rating scale and time tradeoff methods for assessing prostate cancer utilities in men at risk for prostate cancer. Methods. In total, 194 men who were biopsy negative for prostate cancer were randomly assigned to complete 2 preference assessment modules, either conjoint analysis and a rating scale module or conjoint analysis and a time tradeoff module. Each participant's most important attribute was identified and evaluated in relation to age group (age <65, age 65 and older), education (high school, some college, college graduate), race/ethnicity (white, black, Latino), and relationship status (in significant relationship v. not). The methods were also evaluated in terms of ease of use and satisfaction. Results. Rating scales were rated as easiest to use and respondents were more satisfied with rating scales and conjoint in comparison to time tradeoffs. Rating scales and conjoint measures demonstrated significantly higher internal validity compared to time tradeoff when evaluated through R² of the fitted utility function. The 3 methods were similar in terms of predictive validity, but conjoint analysis outperformed the rating scale method when patients were presented with novel combinations of attribute levels (68% correct v. 43%, P = 0.003). Conclusions. Rating scales and conjoint analysis exercises offer greater ease of use and higher satisfaction when measuring patient preferences in men biopsied for prostate cancer in comparison to time tradeoff exercises. Conjoint analysis may be a more robust approach to preference measurement for men at risk for prostate cancer.

Normative Profile of Health-Related Quality of Life for Hong Kong General Population Using Preference-Based Instrument EQ-5D-5L

OBJECTIVES

To establish a normative profile of health-related quality of life (HRQoL) for Hong Kong (HK) Chinese residents aged 18 years and above and to examine the relationship between socioeconomic characteristics and health conditions and the preference-based health index.

METHODS

We recruited 1014 representative Cantonese-speaking residents across 18 geographical districts. The normative profiles of HRQoL were derived using established HK value sets. Mean values were computed by sex, age group, and educational attainment to obtain the EQ-5D HK normative profile for the general HK population. To explore the relationships among potential covariates (socioeconomic characteristics and health conditions) and the HK health index, a multivariable homoscedastic Tobit regression model was employed for the analysis.

RESULTS

The mean index value was 0.919 using the EQ-5D-5L HK value set. Younger ages reported greater problems with anxiety or depression than did older ages, whereas older ages reported greater problems with pain or discomfort than did younger ages. Persons with higher educational attainment and those who reported higher life satisfaction reported significantly higher health index scores (P < .05). On the contrary, receiving government allowance and having experienced a serious illness were significantly associated (P < .05) with a lower health index.

CONCLUSIONS

The norm values fully represent the societal preferences of the HK population, and knowledge of societal preferences can enable policy makers to allocate resources and prioritize service planning. The study was conducted with the EuroQol International EQ-5D-5L Valuation Protocol and therefore enabled us to compare the EQ-5D-5L values with other countries to facilitate understanding of societal preferences in different jurisdictions.

New Cost-Effectiveness Methods to Determine Value-Based Prices for Potential Cures: What Are the Options?

Evaluating different approaches to assessing the clinical effectiveness and value of potential cures will be essential to arm the policymaker, payer, and manufacturer communities with a platform that can reward innovation while supporting a sustainable health insurance system. Potential cures will accentuate concerns about substantial uncertainty in long-term outcomes. They will also focus attention on whether broader elements of value need to be incorporated and whether specific social values have a special place in evaluations of potential cures. In addition, the large magnitudes of potential health gain and cost offsets may require new methods before translation into value-based price recommendations. This article analyzes the challenges and presents several options to modify the conduct and presentation of cost-effectiveness analyses to ensure they provide policy-relevant assessments of the value of potential cures.

Health-Related Quality of Life in People Living with Psychotic Illness and Factors Associated with Its Variation

OBJECTIVES

To establish whether the four-dimensional Assessment of Quality of Life (AQoL-4D) produces robust utility values in adults with psychotic illness, and identify health inequalities compared with the general population.

METHODS

The AQoL-4D was completed by 1613 individuals with an International Classification of Diseases, Tenth Revision, psychotic illness in the 2010 Australian National Survey of Psychosis. Utilities were assessed for this sample and 20 subgroups, and were compared with general population norms. Modified Cohen d was used as an index of effect size. Utilities were collapsed into 10 health-related quality-of-life (HRQOL) bands or decades.

RESULTS

HRQOL in people with psychotic illness was half of the maximum achievable utility (half-"full health") with a mean utility of 0.49 (95% confidence interval [CI] 0.48-0.51), and showing substantial variability across subgroups. Participants with essentially normal functioning had the highest mean utility (0.72; 95% CI 0.68-0.77), and those with very poor perceived mental health had the lowest (0.22; 95% CI 0.18-0.26). These subgroups showed the most variability. Negative symptoms also gave rise to substantial variation. Among diagnostic categories, only depressive psychosis had a large effect relative to delusional disorders. The distribution of utilities in people with psychotic illness differed markedly from that in the general population, with 6.8% versus 47.2% having values in the highest decade (>0.90-1.00). Utilities were lower in every age group in people with psychosis.

CONCLUSIONS

Profound HRQOL impacts are revealed by the AQoL-4D in people with psychotic illness, and marked variations in utilities were observed for key subjective and objective measures. We provide a suite of utility values for economic modeling studies and recommend the AQoL-4D for assessing HRQOL in people with psychotic illness.

Whose preferences should be elicited for use in health-care decision-making? A case study using anticoagulant therapy

The question of whose preferences to elicit in health-state valuation has been widely discussed in the literature. The importance of this debate lies in the fact that health-state utility values are used in health technology assessment (HTA); therefore, an individual's preferences can influence decision-making. If preferences differ across groups, making decisions based on one group's preferences may be suboptimal for the other. Preferences for benefits, risks, experiences and health states associated with anticoagulant therapies have been elicited by researchers due to the underutilization of warfarin and the introduction of non-vitamin K antagonist oral anticoagulants. The majority of existing studies elicit preferences from patient populations as opposed to other stakeholders such as the general public. This paper extends the preference debate by using this clinical area as a case study, with a particular focus on HTA guidelines and the recent advocacy of the use of preference information in benefit-risk assessments.

Value of Genetic Testing for Hereditary Colorectal Cancer in a Probability-Based US Online Sample

BACKGROUND

. While choices about genetic testing are increasingly common for patients and families, and public opinion surveys suggest public interest in genomics, it is not known how adults from the general population value genetic testing for heritable conditions. We sought to understand in a US sample the relative value of the characteristics of genetic tests to identify risk of hereditary colorectal cancer, among the first genomic applications with evidence to support its translation to clinical settings.

METHODS

. A Web-enabled choice-format conjoint survey was conducted with adults age 50 years and older from a probability-based US panel. Participants were asked to make a series of choices between 2 hypothetical blood tests that differed in risk of false-negative test, privacy, and cost. Random parameters logit models were used to estimate preferences, the dollar value of genetic information, and intent to have genetic testing.

RESULTS

. A total of 355 individuals completed choice-format questions. Cost and privacy were more highly valued than reducing the chance of a false-negative result. Most (97% [95% confidence interval (CI)], 95%-99%) would have genetic testing to reduce the risk of dying of colorectal cancer in the best scenario (no false negatives, results disclosed to primary care physician). Only 41% (95% CI, 25%-57%) would have genetic testing in the worst case (20% false negatives, results disclosed to insurance company).

CONCLUSIONS

. Given the characteristics and levels included in the choice, if false-negative test results are unlikely and results are shared with a primary care physician, the majority would have genetic testing. As genomic services become widely available, primary care professionals will need to be increasingly knowledgeable about genetic testing decisions.

Do Probability and Certainty Equivalent Techniques Lead to Inconsistent Results? Evidence from Gambles Involving Life-Years and Quality of Life

BACKGROUND

Within the standard gamble approach to the elicitation of health preferences, no previous studies compared probability equivalent (PE) and certainty equivalent (CE) techniques

OBJECTIVE

This study aimed to explore the differences between CE and PE techniques when payoffs are expressed in terms of life-years or quality of life.

METHODS

Individuals were interviewed through both CE and PE techniques within an experimental setting. Inferential statistics and regression analysis where applied to process data. Order and sequence effect were also investigated.

RESULTS

On average, the elicitation technique did not affect individuals' risk attitude significantly. Individuals proved to be risk averse in gambles concerning life-years and risk seekers in those concerning quality of life. No order or sequence effect was observed. Risk premium, measuring the strength of risk attitude as the percentage variation between the individual's estimated PE or CE and the risk neutral PE or CE, was affected by the kind of gamble that the interviewee is presented with. It increased in gambles concerning health profiles, denoting a stronger risk propensity, and decreased in gambles concerning life years, denoting a stronger risk aversion.

CONCLUSION

The choice of the elicitation technique did not affect the individuals' risk attitude significantly, which instead was sensitive to the kind of gamble.

A Review and Meta-analysis of Colorectal Cancer Utilities

OBJECTIVE

To perform a systematic review of utility weights for colorectal cancer (CRC) health states reported in the scientific literature and to determine the effects of disease factors, patient characteristics, and utility methods on utility values.

METHODS

We identified 26 articles written in English and published from January 1980 to January 2013, providing 351 unique utilities for CRC health states elicited from 6546 unique respondents. The CRC utility data were analyzed using linear mixed-effects models with CRC type, stage, time to or from initial care, utility measurement instrument, and administration method as independent variables.

RESULTS

In the base case model, the estimated utility for a patient with stage I to III CRC more than 1 year after surgery, rated using a self-administered time tradeoff instrument, was 0.90. Stage, time to or from initial care, and utility measurement instrument were associated with statistically significant utility differences ranging from -0.19 to 0.02. Utilities for patients with stage IV cancer were 0.19 lower (P < 0.001) than for those with stage I to III cancer. Utilities elicited at more than 1 year after surgery were 0.05 higher than those elicited at 3 months after surgery (P = 0.008). Estimates of differences between utility measurement instruments were sensitive to how repeated scores in the same patient group were treated, and other findings were sensitive to how the disease stage was modeled and method of administration.

CONCLUSIONS

Variations in reported utilities are associated with factors such as cancer stage, time to or from initial care, and utility measurement instrument. More research is needed to study why apparently similar patients report different quality of life.

A program of methodological research to arrive at the new international EQ-5D-5L valuation protocol

OBJECTIVES

To describe the research that has been undertaken by the EuroQol Group to improve current methods for health state valuation, to summarize the results of an extensive international pilot program, and to outline the key elements of the five-level EuroQol five-dimensional (EQ-5D-5L) questionnaire valuation protocol, which is the culmination of that work.

METHODS

To improve on methods of health state valuation for the EQ-5D-5L questionnaire, we investigated the performance of different variants of time trade-off and discrete choice tasks in a multinational setting. We also investigated the effect of three modes of administration on health state valuation: group interviews, online self-completion, and face-to-face interviews.

RESULTS

The research program provided the basis for the EQ-5D-5L questionnaire valuation protocol. Two different types of tasks are included to derive preferences: a newly developed composite time trade-off task and a forced-choice paired comparisons discrete choice task. Furthermore, standardized blocked designs for the selection of the states to be valued by participants were created and implemented together with all other elements of the valuation protocol in a digital aid, the EuroQol Valuation Technology, which was developed in conjunction with the protocol.

CONCLUSIONS

The EuroQol Group has developed a standard protocol, with accompanying digital aid and interviewer training materials, that can be used to create value sets for the EQ-5D-5L questionnaire. The use of a well-described, consistent protocol across all countries enhances the comparability of value sets between countries, and allows the exploration of the influence of cultural and other factors on health state values.

Sacroiliac joint pain: burden of disease

Objectives

The sacroiliac joint (SIJ) is an important and significant cause of low back pain. We sought to quantify the burden of disease attributable to the SIJ.

Methods

The authors compared EuroQol 5D (EQ-5D) and Short Form (SF)-36-based health state utility values derived from the preoperative evaluation of patients with chronic SIJ pain participating in two prospective clinical trials of minimally invasive SIJ fusion versus patients participating in a nationally representative USA cross-sectional survey (National Health Measurement Study [NHMS]). Comparative analyses controlled for age, sex, and oversampling in NHMS. A utility percentile for each SIJ subject was calculated using NHMS as a reference cohort. Finally, SIJ health state utilities were compared with utilities for common medical conditions that were published in a national utility registry.

Results

SIJ patients (number [n]=198) had mean SF-6D and EQ-5D utility scores of 0.51 and 0.44, respectively. Values were significantly depressed (0.28 points for the SF-6D utility score and 0.43 points for EQ-5D; both P<0.0001) compared to NHMS controls. SIJ patients were in the lowest deciles for utility compared to the NHMS controls. The SIJ utility values were worse than those of many common, major medical conditions, and similar to those of other common preoperative orthopedic conditions.

Conclusion

Patients with SIJ pain presenting for minimally invasive surgical care have marked impairment in quality of life that is worse than in many chronic health conditions, and this is similar to other orthopedic conditions that are commonly treated surgically. SIJ utility values are in the lowest two deciles when compared to control populations.

Methods for Performing Survival Curve Quality-of-Life Assessments

BACKGROUND

Many medical decisions involve an implied choice between alternative survival curves, typically with differing quality of life. Common preference assessment methods neglect this structure, creating some risk of distortions.

METHODS

Survival curve quality-of-life assessments (SQLA) were developed from Gompertz survival curves fitting the general population's survival. An algorithm was developed to generate relative discount rate-utility (DRU) functions from a standard survival curve and health state and an equally attractive alternative curve and state. A least means squared distance algorithm was developed to describe how nearly 3 or more DRU functions intersect. These techniques were implemented in a program called X-Trade and tested.

RESULTS

SQLA scenarios can portray realistic treatment choices. A side effect scenario portrays one prototypical choice, to extend life while experiencing some loss, such as an amputation. A risky treatment scenario portrays procedures with an initial mortality risk. A time trade scenario mimics conventional time tradeoffs. Each SQLA scenario yields DRU functions with distinctive shapes, such as sigmoid curves or vertical lines. One SQLA can imply a discount rate or utility if the other value is known and both values are temporally stable. Two SQLA exercises imply a unique discount rate and utility if the inferred DRU functions intersect. Three or more SQLA results can quantify uncertainty or inconsistency in discount rate and utility estimates. Pilot studies suggested that many subjects could learn to interpret survival curves and do SQLA.

LIMITATIONS

SQLA confuse some people. Compared with SQLA, standard gambles quantify very low utilities more easily, and time tradeoffs are simpler for high utilities. When discount rates approach zero, time tradeoffs are as informative and easier to do than SQLA.

CONCLUSIONS

SQLA may complement conventional utility assessment methods.

Patient preferences for coronary computed tomography angiography versus conventional catheter angiography for the diagnosis of coronary artery disease

RATIONALE AND OBJECTIVES

The aims of the study were: 1) to assess the baseline health-related quality of life (HRQOL) of patients with coronary artery disease (CAD) using the standard gamble; 2) to evaluate and compare patients' preference for catheter versus computed tomography (CT) coronary angiography using the wait tradeoff (WTO) and rating scales; and 3) to calculate test disutility for catheter and CT coronary angiography.

MATERIALS AND METHODS

Thirty patients with CAD who underwent both CT and catheter angiography were interviewed by telephone within 6 months of testing. Patients were asked about their baseline symptoms and quality of life, their experience preparing for both CT and catheter angiography, their desire to undergo CT or catheter angiography, and immediate treatment versus having a waiting period between test results and treatment for a hypothetical "ideal test" with no side effects. Test disutility for CT and catheter angiography were calculated and compared.

RESULTS

The mean and median baseline HRQOL utility values were 0.72 and 0.91. The patients were willing to wait a mean (median) time of 12 (3) days after the ideal test for the test results to avoid undergoing CT angiography. They were willing to wait a mean (median) of 7 (3) days after the ideal test for test results, to avoid undergoing catheter angiography. There was no significant difference between waiting times or between patients' rating for their experience preparing for the two tests. Test disutility for CT angiography was 1.30 quality-adjusted life days (QALD) versus 2.16 QALD for catheter angiography (P > .05).

CONCLUSION

There was no significant difference in patient preference and test disutility between CT and catheter angiography in our small series. Future rigorously planned and adequately powered studies are required to confirm these findings in larger patient populations.

Proximity to disease and perception of utility: physicians' vs patients' assessment of treatment options for ulcerative colitis

BACKGROUND

Physician values regarding the benefit of continued medical therapy vs colectomy for moderate ulcerative colitis have not been defined. If physicians perceive these states differently than patients, their therapeutic recommendations may not align with patient values.

OBJECTIVE

This study aimed to compare physician and patient willingness to trade life years with moderately active ulcerative colitis vs undergoing colectomy.

DESIGN

This survey of physicians' and patients' utility values used standardized scenarios for moderately active ulcerative colitis and colectomy.

SETTING

The investigation was conducted at a tertiary academic medical center.

METHODS

Gastroenterologists, colorectal surgeons, and patients with ulcerative colitis who were either living with moderate disease or were postcolectomy completed the survey.

MAIN OUTCOME MEASURES

Utility values were measured by the use of the time trade-off method.

RESULTS

We surveyed 17 physicians, 150 postcolectomy patients, and 69 patients with moderate ulcerative colitis. Utility values for ulcerative colitis and colectomy states were (0.87, 0.95), (0.86, 0.92), and (0.91, 0.91). On average, physicians and postcolectomy patients assessed the utility of life with ulcerative colitis more poorly than the postcolectomy state. Patients with moderately active ulcerative colitis who had not undergone colectomy viewed both health states equally.

LIMITATIONS

This study was limited by the physician subject sample size.

CONCLUSIONS

Patients living with moderate ulcerative colitis value the pre- and postcolectomy states differently than physicians and postcolectomy patients. Recognizing the differences between their own and patients' values may help physicians to better counsel patients preoperatively. In addition, exposure to postcolectomy patients may help those with moderate disease who are weighing the comparative benefits of colectomy.

Quantifying the decrement in utility from perceived side effects of combination antiretroviral therapies in patients with HIV

BACKGROUND

The decrement in utility attributable to side effects from combination antiretroviral therapy (CART) is unknown and likely to influence clinical decisions regarding CART initiation and cost-effectiveness.

OBJECTIVE

To quantify the decrement in utility attributable to side effects from CART.

METHODS

We estimated SF-6D utilities (quality-of-life weights on a scale from 0.29 [worst possible health] to 1.00 [perfect health]) from SF-12 scores among patients with HIV in the Veterans Aging Cohort Study by using a published and validated conversion algorithm. We then compared utilities among patients who: 1) did not have bothersome symptoms while taking CART; 2) had bothersome symptoms that they thought might be due to CART; and 3) had bothersome symptoms that they were confident were due to CART; we controlled for other characteristics known to influence quality of life and stratified analyses by CD4 count.

RESULTS

Among 1864 patients with available data, symptoms perceived to be attributable to CART were associated with a mean (95% confidence interval) decrement in utility of 0.06 (0.05, 0.08) points in univariate analyses and 0.08 (0.06, 0.10) in multivariable analyses, clinically significant differences that are comparable to utility decrements reported for partial impotence or mild angina. Other significant predictors of changes in SF-6D utilities were hazardous alcohol consumption, recent drug use, cigarette smoking, homelessness, and African American race (R(2) = 0.12). Stratifying by CD4 count, symptoms attributable to CART side effects decreased utility by 0.03 to 0.08 points.

CONCLUSIONS

Symptoms perceived to be related to CART are associated with a substantial decrement in utility.

Agreement between prostate cancer patients and their clinicians about utilities and attribute importance

PURPOSE

To examine the agreement between prostate cancer patients' utilities for selected health states and their rankings of the importance of six attributes of the health states and the clinicians' judgements of what would be in the patients' best interests.

METHOD

Patients with newly diagnosed localized prostate cancer individually completed a time trade-off utility assessment shortly after being diagnosed. The health states evaluated were constructed from a multi-attribute utility model that incorporated six aspects of living with the disease and outcomes of treatment. Each patient assessed his current health state and three hypothetical states that might occur in the future, and provided rankings of the importance of the six attributes. The clinicians caring for each patient independently provided their views of what utilities and importance rankings would be in the patient's best interest.

RESULTS

The across-participant correlations between patients' and clinicians' utilities were very low and not statistically significant. Across-participant correlations between patient and clinician importance rankings for the six attributes were also low. Across-health state and across-attribute correlations between utilities or importance rankings were highly variable across patient-clinician pairs.

CONCLUSION

In the clinical settings studied, there is not a strong relationship between valuations of current and possible future health states by patients with newly diagnosed prostate cancer and their clinicians. Implications of these results for substituted judgement, when clinicians advise their patients or recommend a treatment strategy, are discussed.