Repository logo
 

Search Results

Now showing 1 - 3 of 3
  • A hybrid modelling approach for eliciting health state preferences: the Portuguese EQ-5D-5L value set
    Publication . Ferreira, Pedro L.; Antunes, Patricia; Ferreira, Lara; Pereira, LN; Ramos-Goni, Juan M.
    Background The EQ-5D is a generic preference-based quality of life measure considered useful for supporting clinical and policy decisions by providing utility values that can easily be converted into quality-adjusted life years to be integrated in cost-utility economic evaluations. Although the three-level classification system of the EuroQol questionnaire (EQ-5D-3L) is still the most popular preference-based instrument used worldwide, several studies reported a ceiling effect on this version, especially in healthy and/or young individuals. In 2009, the EuroQol Group introduced a five-level EQ-5D, which expands the descriptive system from three to five levels within the same five dimensions. For this version to be used in health economic evaluation, societal values need to be assigned to the 3125 health states generated by this instrument. Objectives The aims of this study were to elicit the EQ-5D-5L health state preferences from the general Portuguese population and to derive the Portuguese value set for the EQ-5D-5L. Methods A representative sample of the Portuguese general population aged above 18 years was stratified by age and gender (n = 1451). Between October 2015 and July 2016, 28 interviewers carried out a series of 1-h-long computer-assisted personal interviews following the EuroQol Valuation Technology protocol. Each interview included the valuation of ten health states using the composite time trade-off (cTTO) and seven pairs of discrete choice experiments (DCEs). A standardized tool for quality control was used to assess the quality of the data as well as direct supervision and cross-examination of 10% of the global sample size. Data from both cTTO and DCE valuation tasks were modelled using a censored heteroskedastic hybrid model. Results Interviewers complied with the quality control protocol in providing high-quality valuation data. The hybrid econometric model had consistent and significant parameters. The derived societal values for the Portuguese population ranged from - 0.603 to 1. Conclusion This study provided the Portuguese value set for the EQ-5D-5L on the basis of a hybrid econometric model using cTTO and DCE data. These results represent the preferences of the Portuguese population and are recommended to inform health decision-making in Portugal.
  • Contribution for the validation of the portuguese version of EQ-5D
    Publication . Ferreira, Pedro Lopes; Ferreira, Lara Noronha; Pereira, Luis Nobre
    Introduction: The EQ-5D allows the achievement of two essential components of any measure of health-related quality of life to be used in cost-utility economic evaluations: (i) a profile describing the health status in terms of domains or dimensions; and (ii) a numeric value associated with the health status described. Aim: The Portuguese version of the EQ-5D questionnaire was completed in 1998, based on guidelines set by the EuroQol Group, including translation and back translation procedures. Despite its wide use in Portugal, until now it had not yet been published studies that initially led to the Portuguese version and the guarantee of acceptability, reliability and validity. The purpose of this article is to document these first values relating to the Portuguese version of the EQ-5D. Material and Methods: We used three different samples: a first one with 1,500 individuals representative of the Portuguese population; a second with 140 individuals just intended for the reliability test; and a third sample with 643 individual patients with cataracts, asthma, chronic obstructive pulmonary disease, or rheumatoid arthritis. Results: The acceptability was assessed by the number of missing responses. It was also found a marked ceiling effect, with a large part of the sample not reporting any problems in the dimensions of the EQ-5D. Discussion: The construct validity was tested by examining the degree to which low values of EQ-5D were positively associated with increasing age, being female, and the sick, as well as the values of dimensions of the SF-36v2 scale. Convergent validity was based on correlations between EQ-5D values and other specific measures. The EQ-5D showed moderate to high correlations with other disease-specific measures of health status and health related quality of life. Conclusion: We can state that the Portuguese version of the EQ-5D has a good accessibility, reliability and validity in measuring health.
  • Comparing the performance of the SF-6D and the EQ-5D in different patient groups
    Publication . Ferreira, Lara N.; Ferreira, Pedro L.; Pereira, Luis N.
    Introduction: This research aims to explore the performance of the SF-6D and the EQ-5D in patients suffering from asthma, chronic obstructive pulmonary disease, cataracts, and rheumatoid arthritis. In particular, the aim of this research is twofold: 1) to study the level of agreement between the indexes and the descriptive systems of the dimensions of the SF-6D and the EQ-5D, and 2) to analyze the discriminative ability of the instruments. Material and Methods: A sample of 643 patients completed both the SF-36v2 and the EQ-5D. The discriminative ability of the instruments was analyzed. Furthermore, the level of agreement between the indexes and the descriptive systems of the dimensions of the SF-6D and the EQ-5D were studied. The level of agreement between instruments was investigated using correlation coefficients and the Bland-Altman plots, while the influence of medical condition and other socio-demographic variables was analyzed using non-parametric tests. Paired-samples tests were used to identify differences between the scores. Results and Discussion: The results show a strong correlation and agreement between both indexes. Overall, questionnaire indexes differ by medical condition and socio-demographic groups and both instruments are able to discriminate between socio-demographic groups. Conclusion: This study confirmed the hypothesis that the SF-6D generates higher utility values in less healthy individuals. The SF-6D and the EQ-5D seem to perform differently in each of the diseases studied since the descriptive statistics differ between instruments and the level of correlation is not uniform. Results show that the instruments generate different utility values, but there is a strong agreement between both indexes. Thus, the two instruments are not interchangeable and their results cannot be directly comparable.