Holistic preferences for 1-year health profiles describing fluctuations in health: the case of chronic obstructive pulmonary disease.

BACKGROUND: There are few empirical studies on the valuation of health profiles that describe the short-term fluctuations of chronic diseases. OBJECTIVE: This study aimed to value chronic obstructive pulmonary disease (COPD) health profiles, which describe the health of these patients over the course of 1 year from a societal perspective. METHODS: We developed 16 COPD health profiles. Each profile combined a description of the severity of COPD during the stable phase with a description of the exacerbation profile in terms of severity, frequency and duration. These profiles were valued by a representative sample of 239 Dutch adults using the visual analogue scale (VAS) and time trade-off (TTO) methods. Value functions were estimated using random effects regression analysis. RESULTS: Both VAS and TTO values consistently decreased as severity of the COPD profiles increased. Estimated TTO values ranged from 0.97 for mild COPD without exacerbations to 0.43 for very severe COPD with one non-serious and one serious exacerbation per year. The estimated decrements in TTO values ranged from 0.010 for having one non-serious exacerbation to 0.088 for having one non-serious plus one serious exacerbation per year. CONCLUSIONS: The value function may be an alternative way to model the joint impact of COPD severity and exacerbations on utility values in health economic modelling studies.

Cost-effectiveness of temozolomide for the treatment of newly diagnosed glioblastoma multiforme: a report from the EORTC 26981/22981 NCI-C CE3 Intergroup Study.

BACKGROUND: The study aimed to compare the cost-effectiveness of concomitant and adjuvant temozolomide (TMZ) for the treatment of newly diagnosed glioblastoma multiforme versus initial radiotherapy alone from a public health care perspective. METHODS: The economic evaluation was performed alongside a randomized, multicenter, phase 3 trial. The primary endpoint of the trial was overall survival. Costs included all direct medical costs. Economic data were collected prospectively for a subgroup of 219 patients (38%). Unit costs for drugs, procedures, laboratory and imaging, radiotherapy, and hospital costs per day were collected from the official national reimbursement lists based on 2004. For the cost-effectiveness analysis, survival was expressed as 2.5 years restricted mean estimates. The incremental cost-effectiveness ratio (ICER) was constructed. Confidence intervals for the ICER were calculated using the Fieller method and bootstrapping. RESULTS: The difference in 2.5 years restricted mean survival between the treatment arms was 0.25 life-years and the ICER was euro37,361 per life-year gained with a 95% confidence interval (CI) ranging from euro19,544 to euro123,616. The area between the survival curves of the treatment arms suggests an increase of the overall survival gain for a longer follow-up. An extrapolation of the overall survival per treatment arm and imputation of costs for the extrapolated survival showed a substantial reduction in ICER. CONCLUSIONS: The ICER of euro37,361 per life-year gained is a conservative estimate. We concluded that despite the high TMZ acquisition costs, the costs per life-year gained are comparable to accepted first-line treatment with chemotherapy in patients with cancer.

On the assessment of preferences for health and duration: maximal endurable time and better than dead preferences.

BACKGROUND: Several studies revealed difficulties with the valuation and analysis of health states deemed worse than dead. These problems may be linked to maximal endurable time (MET) preferences, the phenomenon that for severe states better than dead (BTD), shorter durations are often preferred to longer durations. OBJECTIVE: To test the association between the duration of health states and their valuation. METHODS: A representative sample of 123 Dutch respondents (age range, 18-45 years) valued 5 EQ-5D health states. With a straightforward method using BTD preferences, respondents indicated whether a state of a certain duration is better, equal to, or worse than dead. To validate these BTD preferences, MET preferences (whether a longer duration of a health state is better, equal, or worse than a shorter duration) were collected. RESULTS: BTD and MET preferences were strongly related (P < 0.001). For severe health states, although still judged as better than dead, BTD preferences curved downwards with increasing duration. Such curved BTD patterns occurred in 28% of the respondents, especially for more severe states (P < 0.001). CONCLUSIONS: BTD preferences revealed that the value of moderate and severe states declines with increasing duration, suggesting that health and duration interact. For states worse than dead versus states better than dead, traditional valuation techniques have the drawback that different preference questions are used. Using BTD preferences, however, a single simple preference question can assess states better than dead, as well as states worse than dead.

Cost-effectiveness of physical therapy and general practitioner care for sciatica.

STUDY DESIGN: An economic evaluation alongside a randomized clinical trial in primary care. A total of 135 patients were randomly allocated to physical therapy added to general practitioners' care (n = 67) or to general practitioners' care alone (n = 68). OBJECTIVE: To evaluate the cost-effectiveness of physical therapy and general practitioner care for patients with an acute lumbosacral radicular syndrome (LRS, also called sciatica) compared with general practitioner care only. SUMMARY OF BACKGROUND DATA: There is a lack of knowledge concerning the cost-effectiveness of physical therapy in patients with sciatica. METHODS: The clinical outcomes were global perceived effect and quality of life. The direct and indirect costs were measured by means of questionnaires. The follow-up period was 1 year. The Incremental Cost-effectiveness Ratio (ICER) between both study arms was constructed. Confidence intervals for the ICER were calculated using Fieller's method and using bootstrapping. RESULTS: There was a significant difference on perceived recovery at 1-year follow-up in favor of the physical therapy group. The additional physical therapy did not have an incremental effect on quality of life. At 1-year follow-up, the ICER for the total costs was 6224 euros (95% confidence interval, -10,419, 27,551) per improved patient gained. For direct costs only, the ICER was 837 euros (95% confidence interval, -731, 3186). CONCLUSION: The treatment of patients with LRS with physical therapy and general practitioners'care is not more cost-effective than general practitioners'care alone.

The use of disease-specific outcome measures in cost-utility analysis: the development of Dutch societal preference weights for the FACT-L scale.

INTRODUCTION: The Functional Assessment of Cancer Therapy-Lung (FACT-L) is a validated, sensitive and reliable patient questionnaire that evaluates and quantifies quality of life (QOL) across several domains, including lung cancer-related symptoms. The FACT-L was not designed for use in economic evaluation and does not incorporate preferences into its scoring system. OBJECTIVE: To derive a set of Dutch preference weights for FACT-L health states that can be used to convert FACT-L into a single value that can be used in cost-utility analyses. METHODS: A representative sample of the Dutch population (n = 1076) directly valued an orthogonal set of eight FACT-L health states on a 100-point rating scale with the anchor points 'worst imaginable health state' and 'best imaginable health state'. Eleven FACT-L items were selected to describe the FACT-L health states that were directly valued. Regression analysis was used to interpolate values for all other possible health states. Scores were transformed into values on a scale where 0 indicated dead and 1 indicated full health. RESULTS: The estimated values for FACT-L health states ranged from 0.08 to 0.93. The estimated value sets were applied to FACT-L data of lung cancer patients participating in a clinical study. Significant differences in the mean value and mean gain of 0.12 and 0.07, respectively, were found between patients in remission and patients with progressive disease at 4 weeks' follow-up. CONCLUSION: Our results reaffirmed that the methodology used here is a feasible option to convert data collected with a disease-specific outcome measure into preferences. We concluded that the sensitivity of the derived set of societal preferences to capture differences and changes in clinical health states is an indication of its construct validity.

The transformation of utilities for health states worse than death: consequences for the estimation of EQ-5D value sets.

BACKGROUND: Utilities for health are measured on an interval scale, where 1 refers to full health and 0 refers to death. No theoretical lower boundary on the utilities for states worse than death exists. As a consequence, negative values receive greater weight in the calculation of mean utilities. To avoid this, negative values often are bound at -1. OBJECTIVE: The objective of this study was to compare the effect of 3 methods to bound negative values at -1 on the estimation of EQ-5D value sets: truncation, monotonic, and linear transformation. METHOD: Data of the Dutch EQ-5D valuation study were used. A total of 298 respondents directly valued 17 EQ-5D health states using the time trade-off (TTO) method. Random effects regression analysis was used to interpolate TTO values for all possible EQ-5D states. In the regression analysis the dependent variable is 1 minus the TTO value and the independent variables describe the health state. Two widely used models to estimate EQ-5D value were applied after truncation of negative values and monotonic and linear transformation of negative values. Both models also were estimated on medians. RESULTS: Truncation of negative values gave the largest mean absolute error (MAE); the linear transformation resulted in the smallest MAE. When medians were used for estimation, the MAEs were comparable with the estimation on means. CONCLUSION: The choice of a method to bound negative values is arbitrary and affects the resulting value set. For the estimation of EQ-5D value sets from a societal perspective the use of medians should be considered.

Gender and health care utilization: the role of mental distress and help-seeking propensity.

Many studies report higher levels of health care utilization among women. Understanding how gender influences health care utilization is still unresolved. We developed a model that could explain these gender-related differences. The possible pathways assumed by this model that relate gender to utilization, can be summarized as follows: (1) utilization may be influenced by somatic morbidity, mental distress, perceived symptoms, poor subjective health and propensity to use services; (2) women have higher levels of these variables than men (mediating effect); and (3) the direct effects of some of these variables on utililization are moderated by gender, i.e. they are stronger for women than for men (moderating effect). Data were drawn from a community-based sample of adult enrollees of a sickness fund in the Netherlands, who had responded to a mailed health survey (N = 8698). This survey contained questions on somatic morbidity, mental distress and other mediating variables. Health care utilization was measured prospectively, using data extracted from a claims database held by the sickness fund that covers all types of general health services except general practitioner consultations. The model was tested using structural equation modelling. Women reported more somatic morbidity and mental distress than men did, as well as elevated levels of other mediating variables, which might explain-at least partly-gender related differences in utilization. Differences in propensity to use services were not found. The expected moderating effect of gender could not be demonstrated. That is, we did not find gender related differences in the strength of the relations between mental distress, other mediating variables and utilization. Mental distress is related to utilization in a way that is not gender specific, however, because women report higher levels of mental distress (as well as somatic morbidity), this results in a greater utilization of somatic health care services.

Testing the interval-level measurement property of multi-item visual analogue scales.

BACKGROUND: Conditions were studied that may invalidate health-state values derived from the visual analogue scale (VAS). METHODS: Respondents were asked to place cards with descriptions of EQ-5D health states on a 20 cm EuroQol VAS and modified versions of it, positioning them such that the distances between the states reflect their valuation for these states. Anchor-point bias was examined using the standard EuroQol VAS (n = 212) and a modified version (n = 97) with a different lower anchor. Context bias was examined in another group of respondents (n = 112) who valued three different sets of EQ-5D health states. Marker bias was studied in yet another group of respondents (n = 100) who placed the same EQ-5D states on the standard EuroQol VAS and on a modified VAS without anchors, categories, or measurement markers. RESULTS: No indication for the existence of the anchor-point and the marker bias was found. However, the VAS valuations were significantly affected by the context of the set of health states in the scaling task. CONCLUSION: Advanced methodologies should be incorporated in VAS valuation studies to deal with the context bias.

Is the impact of depressive complaints on the use of general health care services dependent on severity of somatic morbidity?

OBJECTIVE: The aim of this study was to examine the effects of depressive complaints and chronic medical illnesses on prospective somatic health care utilization and the possible heterogeneity of the effect of depressive complaints across levels of medical illness severity. METHODS: Data from a community-based sample of adults (n=9428) were used, of whom a health survey and claims data, indicating health care use, were available. Assessments of depressive complaints and somatic illnesses were based on self-report. Binomial regression analyses were used to study the expected relations. RESULTS: Depressive complaints and somatic morbidity were both positively related to general health care utilization. Somatic morbidity has an attenuating effect on the impact of depressive complaints: If it becomes more severe, the impact of depressive complaints on utilization is reduced. Depressive complaints are especially related to the use of paramedic services, use of prescription drugs, and consultations of medical specialists. CONCLUSION: Depressive complaints predict somatic health care utilization, but somatic morbidity attenuates this relation. Future research on this subject should include interaction effects of depressive complaints and somatic morbidity. Interventions aiming to reduce excess use related to mental distress should be primarily targeted on subjects with mental distress who have no comorbid somatic morbidity.

Inconsistencies in TTO and VAS values for EQ-5D health states.

BACKGROUND: Most EQ-5D health states can be ordered logically. When people assign values to different health states, they may violate this logical order, which can be seen as inconsistencies. OBJECTIVE: The aim of this study was to assess the effect of inconsistently valued EQ-5D health states on mean visual analog scale (VAS) and time trade-off (TTO) values. The authors also examined the effect of removing respondents with high numbers of inconsistent states on the estimation of tariffs, which is used to interpolate values to all possible EQ-5D states from the direct valuation of a subset of states. METHOD: Data from the Dutch EQ-5D valuation study were used. A representative sample of 309 Dutch adults valued 17 EQ-5D health states by VAS and TTO. A state was valued inconsistently when it had a higher value than at least 1 logically better state. Mean values of groups with various numbers of inconsistently valued states were compared. RESULTS: Of the respondents, 65% had inconsistencies for VAS and 89% for TTO. The mean VAS values of consistent respondents tend to be lower. For TTO, those with inconsistencies gave lower values. Removing data of respondents with the highest number of inconsistently valued states for VAS (13%) and TTO (9%) did not result in statistically significant different coefficients in the estimated tariff using all data. CONCLUSION: The majority of respondents valued at least 1 state inconsistently. For both VAS and TTO, the presence of these inconsistencies did not affect the estimated tariffs.

Assessing the construct validity of three indicators of psychological distress in relation to perceived health and physical illness.

OBJECTIVES: The aim of this study is to compare three indicators of psychological distress (PD) on the strength of their association with subjective (or perceived) health and to analyse to what extent these associations will change after adjusting for physical illness measures and other possible confounding variables. METHODS: Data were used from a community-based sample of adults (N=9,428). Psychological distress was measured using three different instruments: the Negative Affect Scale of Bradburn, a nervousness scale, and a self-reported depressive complaints. Physical illness was measured by seven specific chronic conditions, a co-morbidity index of 17 conditions and two disability measures. Subjective health was assessed by a single question. Ordinary least square and logistic regression as well as structural equation modelling were used to analyse the data. RESULTS: The relation between subjective health and PD is strongest in case nervousness and this, or negative affect, are used as indicators of PD. The measure of depressive complaints is less strongly, but still substantially, related to subjective health. After correction for physical illness variables, the change in strength of the association is slightest for depressive complaints and highest for nervousness. Only small differences between negative affect and nervousness were established. These measures, which were more contaminated by physical ill health than depressive complaints, have the strongest association with subjective health both before as well as after correction for physical illness components. CONCLUSION: Negative affect and nervousness are reliable and valid indicators of PD, which can be used to predict subjective health. However, for this purpose, a correction for the confounding effects of physical illness variables will be necessary. The depressive complaints measure is not only less predictive of subjective health but also less contaminated by physical illness variables, making it a better indicator of PD if correction for physical illness variables is not possible.

The relationship between productivity and health-related quality of life: an empirical exploration in persons with low back pain.

OBJECTIVE: In economic evaluation of health care programmes normally health-related quality of life is part of measurement of a programme's effectiveness and productivity part of its costs. In this paper the relationship between quality of life and productivity is highlighted and empirically assessed in persons suffering from low back pain. METHODS: A secondary analysis was performed on data from a sample of 483 patients treated for low back pain. Periodically, both quality of life (EQ-5D) and productivity indicators for both paid and unpaid work were measured. Mean EQ-5D scores were compared for groups of patients classified by level of productivity. The relationship between quality of life and productivity was also assessed using Spearman rank correlation coefficients. RESULTS: Mean EQ-5D scores for patients without productivity losses were a half to a full standard deviation higher than for patients with the lowest levels of productivity. The correlation between quality of life and productivity was moderate. CONCLUSION: Lower levels of quality of life were associated with efficiency loss and absenteeism. However, due to the moderate strength of the relation the use of information on quality of life to model productivity costs in case of absence of productivity data was not recommended.

The relationship between productivity and health-related QOL: an exploration.

In economic evaluation of healthcare programmes both QOL and productivity of patients are aspects to be studied. Normally, the former is part of the measurement of the effectiveness of the programme and the latter is part of the measurement of its costs. In this paper we highlight the relationship between QOL and productivity. Two aspects are discussed: (i) the relationship between perceived productivity and health-state valuations; and (ii) the observed relationship between productivity and QOL. The first aspect relates to the fact that in health-state valuations, respondents may consider income changes and ability to work. While this may have important methodological and practical implications, little empirical evidence exists in this area. The second aspect relates to the fact that the observed productivity of individuals is expected to be related to their health-related QOL. Worse health states are expected to be associated with lower productivity. Again, empirical investigation is lacking; however, this relationship may prove important, for instance in modelling productivity costs with use of information on QOL. This paper explores these relationships between productivity and QOL to stimulate debate and research in this area.

The gap effect: discontinuities of preferences around dead.

BACKGROUND: The assessment of health states considered to be worse than dead is a controversial issue. OBJECTIVE: To investigate how health states are valued when they are close to dead. Differences between adjacent states are compared with the differences between the first positive/first negative state with death. METHODS: A secondary analysis of the EuroQol EQ-5D data of the measurement of valuation and health (MVH) study was made. Visual analog scale (VAS) and time trade-off (TTO) preferences for 43 health states were obtained. Various subsets of 13 states were valued by 3395 respondents. States were rank ordered by their VAS and TTO values. Differences between adjacent states were calculated for the VAS and the positive and negative TTO values. RESULTS: Complete data were obtained in 2997 respondents. The differences between the ordered VAS values were equally large. In contrast, significant gaps around dead were found for the positive as well as the negative TTO values. DISCUSSION: These results are interpreted in light of a descriptive QALY model. This model was expanded to include utilities worse than dead. The VAS task does not pick up that bad states become intolerable, i.e. worse than dead, when they last too long, but the TTO task does. The current QALY model seems to lack descriptive validity for states valued worse than dead and for states with a maimal endurable time.

Health-adjusted premium subsidies in the Netherlands.

The Dutch government has decided to proceed with managed competition in health care. In this paper we report on progress made with health-based risk adjustment, a key issue in managed competition. In 2004 both Diagnostic Cost Groups (DCGs) computed from hospital diagnoses only and Pharmacy-based Cost Groups (PCGs) computed from out-patient prescription drugs are used to set the premium subsidies for competing risk-bearing sickness funds. These health-based risk adjusters appear to be effective and complementary. Risk selection is not a major problem in the Netherlands. Despite the progress made, we are still faced with a full research agenda for risk adjustment in the coming years.

The Pharmacy-based Cost Group model: validating and adjusting the classification of medications for chronic conditions to the Dutch situation.

In 2002, the Dutch government implemented a Pharmacy-based Cost Group (PCG) model in the social health insurance sector. This model uses specific types of medication prescribed to individuals in a base year as markers for chronic conditions, which are then employed to adjust capitation payments to their sickness fund in the subsequent year. In this study, a classification of prescribed medication is derived for 22 chronic conditions, based on an assessment of the relation between prescribed medication and diagnoses indicated by physicians on their prescriptions. Of the 22 chronic conditions in this classification, 13 were included in the PCG model that is currently used in the Netherlands.

Risk adjusted premium subsidies and risk sharing: key elements of the competitive sickness fund market in the Netherlands.

As part of a market-oriented health care reform, in 1991 risk adjusted premium subsidies were introduced in the Dutch social health insurance sector. Currently the premium subsidies are primarily based on demographic variables. To mitigate the obvious inadequacy of these risk adjusters, the system of risk adjustment is supplemented with a system of risk sharing. This paper describes the main characteristics of the Dutch health care system and the development of risk adjustment and risk sharing in the last decade. The effects of introducing financial risk for Dutch sickness funds on risk selection and consumer mobility are analysed. The paper concludes with a description of expected future developments.

Risk adjustment and risk selection on the sickness fund insurance market in five European countries.

From the mid-1990s citizens in Belgium, Germany, Israel, the Netherlands and Switzerland have a guaranteed periodic choice among risk-bearing sickness funds, who are responsible for purchasing their care or providing them with medical care. The rationale of this arrangement is to stimulate the sickness funds to improve efficiency in health care production and to respond to consumers' preferences. To achieve solidarity, all five countries have implemented a system of risk-adjusted premium subsidies (or risk equalization across risk groups), along with strict regulation of the consumers' direct premium contribution to their sickness fund. In this article we present a conceptual framework for understanding risk adjustment and comparing the systems in the five countries. We conclude that in the case of imperfect risk adjustment-as is the case in all five countries in the year 2001-the sickness funds have financial incentives for risk selection, which may threaten solidarity, efficiency, quality of care and consumer satisfaction. We expect that without substantial improvements in the risk adjustment formulae, risk selection will increase in all five countries. The issue is particularly serious in Germany and Switzerland. We strongly recommend therefore that policy makers in the five countries give top priority to the improvement of the system of risk adjustment. That would enhance solidarity, cost-control, efficiency and client satisfaction in a system of competing, risk-bearing sickness funds.

Risk-adjusted capitation payment systems for health insurance plans in a competitive market.

Adequate risk-adjustment is critical to the success of market-oriented healthcare reforms in many countries. Regulated competition among insurers and providers is often a crucial element in these reforms. Consumers may then choose among competing health insurance plans, which are largely financed through premium-replacing risk-adjusted capitation payments. Too crude risk-adjustment, which is common in 2003, provides health insurance plans with incentives for risk selection, which may threaten access to (good quality) healthcare, efficiency and consumer satisfaction. In this review the background and rationale for the implementation of risk-adjusted capitation payments is described. The authors are optimistic about the possibilities for improving the present, crude risk-adjusted capitation payment systems in order to reduce risk selection.

Comparing patients with depressive complaints and patients with chronic medical conditions on their functioning and medical consumption.

BACKGROUND: Several studies have found that depressive complaints are associated with limitations in functioning that are at least comparable with those of chronic medical conditions, such as diabetes or lung diseases. However, the consequences of these associations for the utilization of general health care services are not known, certainly not for health care settings outside the United States. AIMS OF THE STUDY: To investigate the association of depressive complaints with functioning and health care utilization, comparing this with the association of chronic medical conditions with functioning and health care utilization. METHODS: In a community-based sample of Dutch adults (N=9428), chronic conditions (21 types) and depressive complaints were assessed by self-report. Only active conditions and depressive complaints, for which treatment was taking place, were selected for the analyses. Health status and disabilities were also assessed by self-report. Information on the utilization of health care services was based on self-report as well as on data extracted from a claims database. This database also provided information on the use of psychoactive medications. The associations between chronic conditions, depressive complaints and dependent variables were determined by analysis of variance or regression analysis, adjusting for possibly confounding factors (gender, age, living conditions). RESULTS: Depressive complaints, more than any chronic condition (except back problems), were associated with fatigue, poor subjective health and days spent in bed. Those having depressive complaints visited their general practitioner (GP) more often than the others. They also contacted a medical specialist more often than other patient categories, apart from patients with heart diseases. The combination of depressive complaints and chronic medical conditions was not associated with increased utilization or lower functioning. CONCLUSION: Depressive complaints are not only connected to functioning, but also to the utilization of general health care services. The strength of these associations is comparable with that of chronic medical conditions. This study stresses the pertinence of (research on) the management and treatment of patients with depressive complaints in general health care settings.