The decision evaluation scales

There are several instruments to assess how patients evaluate their medical treatment choice. These are used to evaluate decision aids. Our objective is to investigate which psychological factors play a role when patients evaluate their medical treatment choices. A pool of 36 items was constructed, covering concepts such as uncertainty about and satisfaction with the decision, informed choice, effective decision making, responsibility for the decision, perceived riskiness of the choice, and social support regarding the decision. This pool was presented to patients at high risk for breast and ovarian cancer, awaiting a genetic test result, and facing the choice between prophylactic surgery or screening. Additional measures were assessed for validation purposes. Factor and Rasch analyses were used for factor and item selection. Construct validity of emerging scales was assessed by relating them with the additional measures. Three factors suminarised the psychological factors concerning decision evaluation: Satisfaction-Uncertainty, Informed Choice, and Decision Control. Reliabilities (Cronbach's alpha) of the three scales were 0.79, 0.85, and 0.75, respectively. Construct validity hypotheses were confirmed. The first two scales were similar to previously developed scales. Of these three scales, the Decision Control scale correlated most strongly with the well-being measures, was associated with partner's agreement and physician's preferences as perceived by patients, and with a negative emotional reaction to the information material. In conclusion, the Decision Control scale is a new scale to evaluate decision aids, and it appears to be rooted in health psychological theories. (c) 2004 Elsevier Ireland Ltd. All rights reserved.</p

Expected survival with and without second-line palliative chemotherapy: who wants to know?

Background According to surveys, many patients with advancedcancer wish to receive survival information.Objective This study invest igated information preferences by offer-ing patients a decision aid (DA) with infor mation on expected sur-vival for two treatment options: supportive care with or withoutsecond-line palliative chemotherapy. Predicto rs of accepting sur-vival information were explored.Design Eligible patients in this multicentre prospective study wereoffered secon d-line chemotherapy for advanced breast or colorectalcancer. A nurse presented a DA on second-line treatment andasked patients whether they desired information on (i) adverseevents, (ii) tumour response and (iii) survival. Data on 50 clinicaland psychosocial patient characteristics were collected from inclu-sion forms and patient questionnaires.Results Seventy-seven patients received a DA; median age62 years (range 32–80), 61% female, 77% colorectal cancer. Fifty-seven patients (74%; 95% CI 64–84) desired survival information.Four psychosocial characteristics (e.g . deliberative decision style)independently predicted information desire. However, the use ofthese characteristics to predict information desire hardly outper-formed a simple prediction rule.Conclusions Many patients desired information on expected sur-vival when deciding about second-line treatment. However, ourexploratory analysis indicated that patients desiring this informa-tion could not be identified based on their clinical or psychosocialcharacteristics. These findings can help encourage candid discus-sions about expected survival. Health professionals should be care-ful not to make implicit assumptions of information desire based on patient characteristics, but to explicitly ask patients if survivalinformation is desired, and act accordingly

On the (not so) constant proportional trade-off in TTO

Abstract. Purpose: The linear and power QALY models require that people in Time Trade-off (TTO) exercises sacrifice the same proportion of lifetime to obtain a health improvement, irrespective of the absolute amount. However, evidence on these constant proportional trade-offs (CPTOs) is mixed, indicating that these versions of the QALY model do not represent preferences. Still, it may be the case that a more general version of the QALY model represents preferences. This version has the property that people want to sacrifice the same proportion of utilities of lifetime for a health improvement, irrespective of the amount of this lifetime. Methods: We use a new method to correct TTO scores for utility of life duration and test whether decision makers trade off utility of duration and quality at the same rate irrespective of duration. Results: We find a robust violation of CPTO for both uncorrected and corrected TTO scores. Remarkably, we find higher values for longer durations, contrary to most previous studies. This represents the only study correcting for utility of life duration to find such a violation. Conclusions: It seems that the trade-off of life years is indeed not so constantly proportional and, therefore, that health state valuations depend on durations

The way that you do it? An elaborate test of procedural invariance of TTO, using a choice-based design

The time tradeoff (TTO) method is often used to derive Quality-Adjusted Life Year health state valuations. An important problem with this method is that results have been found to be responsive to the procedure used to elicit preferences. In particular, fixing the duration in the health state to be valued and inferring the duration in full health that renders an individual indifferent, causes valuations to be higher than when the duration in full health is fixed and the duration in the health state to be valued is elicited. This paper presents a new test of procedural invariance for a broad range of time horizons, while using a choice-based design and adjusting for discounting. As one of the known problems with the conventional procedure is the violation of constant proportional tradeoffs (CPTO), we also investigate CPTO for the alternative TTO procedure. Our findings concerning procedural invariance are rather supportive for the TTO procedure. We find no violations of procedural invariance except for the shortest gauge duration. The results for CPTO are more troublesome: TTO scores depend on gauge duration, reinforcing the evidence reported when using the conventional procedure

The relationship between change in subjective outcome and change in disease: a potential paradox

Contains fulltext : 87756.pdf (publisher's version ) (Closed access)BACKGROUND: Response shift theory suggests that improvements in health lead patients to change their internal standards and re-assess former health states as worse than initially rated when using retrospective ratings via the then-test. The predictions of response shift theory can be illustrated using prospect theory, whereby a change in current health causes a change in reference frame. Therefore, if health deteriorates, the former health state will receive a better rating, whereas if it improves, the former health state will receive a worse rating. OBJECTIVE: To explore the predictions of response shift and prospect theory by relating subjective change to objective change. METHODS: Baseline and 3-month follow-up data from a cohort of rheumatoid arthritis patients (N = 197) starting on TNFalpha-blocking agents were used. Objective disease change was classified according to a disease-specific clinical outcome measure (DAS28). Visual analogue scales (VAS) for general health (GH) and pain were used as self-reported measures. Three months after starting on anti-TNFalpha, patients used the then-test to re-rate their baseline health with regard to general health and pain. Differences between then-test value and baseline values were calculated and tested between improved, non-improved and deteriorated patients by the Student t-test. RESULTS: At 3 months, 51 (25.9%) patients had good improvement in health, 83 (42.1%) had moderate improvement, and 63 (32.0%) had no improvement or deteriorated in health. All patients no matter whether they improved, did not improve, or even became worse rated their health as worse retrospectively. The difference between the then-test rating and the baseline value was similarly sized in all groups. CONCLUSION: More positive ratings of retrospective health are independent of disease change. This suggests that patients do not necessarily change their standards in line with their disease change, and therefore it is inappropriate to use the then-test to correct for such a change. If a then-test is used to correct for shifts in internal standards, it might lead to the paradoxical result that patients who do not improve or even deteriorate increase significantly on self-reported health and pain. An alternative explanation for differences in retrospective and prospective ratings of health is the implicit theory of change which is more successful in explaining our results than prospect theory.1 september 201

Cultural Values: Can They Explain Differences in Health Utilities between Countries?

Introduction. Health utilities are widely used in health care. The distributions of utilities differ between countries; some countries more often report worse than dead health states, while mild states are valued more or less the same. We hypothesize that cultural values explain these country-related utility differences. Research Question. What is the effect of sociodemographic background, methodological factors, and cultural values on differences in health utilities? Methods and Analyses. Time tradeoff data from 28 EQ-5D valuation studies were analyzed, together with their sociodemographic variables. The dependent variable was Δu, the utility difference between mild and severe states. Country-specific cultural variables were taken from the World Values Survey. Multilevel models were used to analyze the effect of sociodemographic background, methodology (3L v. 5L), and cultural values on Δu. Intraclass correlation (ICC) for country variation was used to assess the impact of the predicting variables on the variation between countries. Results. Substantial variation in Δu was found between countries. Adding cultural values did not reduce ICCs for country variation. Sociodemographic background variables were only weakly associated with Δu and did not affect the ICC. Δu was 0.118 smaller for EQ-5D-5L studies. Discussion. Δu varies between countries. These differences were not explained by national cultural values. In conclusion, despite correction for various variables, utility differences between countries remain substantial and unexplained. This justifies the use of country-specific value sets for instruments such as the EQ-5D

Kwaliteit van leven meten in economische evaluaties: het Nederlands EQ-5D-tarief

OBJECTIVE: To value EQ-5D health states by a general Dutch public. EQ-5D is a standardised questionnaire that is used to calculate quality-adjusted life-years for cost-utility analysis. DESIGN: Descriptive. METHOD: A sample of 309 Dutch adults from Rotterdam and surroundings was asked to value 17 EQ-5D health states using the time trade-off method. Regression analysis was applied to the valuations of these 17 health states. By means of the estimated regression coefficients, which together constitute the so-called Dutch tariff, valuations can be determined for all possible EQ-5D health states. These values reflect the relative desirability of health states on a scale where 1 refers to full health and 0 refers to death. Societal valuations are necessary in order to correct life-years for the quality of life. RESULTS: Complete data were obtained from 298 persons. Theywere representative for the Dutch population as far as age, gender and subjective health were concerned, but had a somewhat higher educational level. The estimated Dutch EQ-5D tariff revealed that the respondents assigned the most weight to (preventing) pain and anxiety or depression, followed by mobility, self-care and the activities of daily living. The Dutch tariff differed from the UK ('Measurement and Valuation of Health') tariff, which is currently used in Dutch cost-utility analyses. Compared to UK respondents, Dutch respondents assigned more weight to anxiety and depression and less weight to the other dimensions. Conclusion. The valuation of health states by this representative Dutch study group differed from the valuation that is currently used in Dutch cost-utility analyses

A Value Set for the EQ-5D-Y-3L in the Netherlands

Background and Objective: There is increasing interest in preference-accompanied measures of health for paediatric populations. The child-friendly EQ-5D version, EQ-5D-Y-3L, is one such instrument, but the lack of a Dutch value set prevents its use in economic evaluations of healthcare interventions in the Netherlands. This study aims at covering this gap by collecting preferences using a standardised protocol for deriving EQ-5D-Y-3L value sets. Methods: Composite time trade-off data were collected using videoconferencing interviews, with each respondent completing ten composite time trade-off tasks. Discrete choice experiment data were collected using an online survey, with respondents each completing 15 paired comparisons. Respondents completed these tasks considering what they prefer for a hypothetical 10-year-old child. Discrete choice experiment data were analysed using a ten-parameter mixed-logit model and anchored to the quality-adjusted life-year scale using the mean observed composite time trade-off values. Results: The study collected preferences for 197 respondents using composite time trade-off and for 959 respondents using a discrete choice experiment. The discrete choice experiment sample was representative for the Dutch population in terms of age and sex. The level 3 weight for pain/discomfort was the largest, followed by feeling worried, sad or unhappy, usual activities, mobility and self-care. Health state values ranged between −0.218 and 1. Conclusions: This study generated a Dutch value set for the EQ-5D-Y-3L, which can be used for the computation of quality-adjusted life-years for economic evaluations of healthcare interventions in paediatric populations