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Background: Discrete choice experiments (DCEs) are widely used to elicit health state preferences. However, additional information is required to transform values to a scale with dead valued at 0 and full health valued at 1. This paper presents DCE-VAS, an understandable and easy anchoring method with low participant burden based on the visual analogue scale (VAS)., Methods: Responses from 1450 members of the UK general public to a discrete choice experiment (DCE) were analysed using mixed logit models. Latent scale valuations were anchored to a full health = 1, dead = 0 scale using participants' VAS ratings of three states including the dead. The robustness of results was examined. This included a filtering procedure with the influence each individual respondent had on valuation being calculated, and those whose influence was more than two standard deviations away from the mean excluded., Results: Coefficients in all models were in the expected direction and statistically significant. Excluding respondents who self-reported not understanding the VAS task did not significantly influence valuation, but excluding a small number who valued 33333 extremely low did. However, after eight respondents were removed via the filtering procedure, valuations were robust to removing other participants., Conclusion: DCE-VAS is a feasible way of anchoring DCE results to a 0-1 anchored scale with low additional respondent burden.

Purpose: Preference-based measures are essential for producing quality-adjusted life years (QALYs) that are widely used for economic evaluations. In the absence of such measures, mapping algorithms can be applied to estimate utilities from disease-specific measures. This paper aims to develop mapping algorithms between the MacNew Heart Disease Quality of Life Questionnaire (MacNew) instrument and the English and the US-based EQ-5D-5L value sets., Methods: Individuals with heart disease were recruited from six countries: Australia, Canada, Germany, Norway, UK and the US in 2011/12. Both parametric and non-parametric statistical techniques were applied to estimate mapping algorithms that predict utilities for MacNew scores from EQ-5D-5L value sets. The optimal algorithm for each country-specific value set was primarily selected based on root mean square error (RMSE), mean absolute error (MAE), concordance correlation coefficient (CCC), and r-squared. Leave-one-out cross-validation was conducted to test the generalizability of each model., Results: For both the English and the US value sets, the one-inflated beta regression model consistently performed best in terms of all criteria. Similar results were observed for the cross-validation results. The preferred model explained 59 and 60% for the English and the US value set, respectively. Linear equating provided predicted values that were equivalent to observed values., Conclusions: The preferred mapping function enables to predict utilities for MacNew data from the EQ-5D-5L value sets recently developed in England and the US with better accuracy. This allows studies, which have included the MacNew to be used in cost-utility analyses and thus, the comparison of services with interventions across the health system.

Background: Standard methods for eliciting the preference data upon which 'value sets' are based generally have in common an aim to 'uncover' people's preferences by asking them to evaluate a subset of health states, then using their responses to infer their preferences over all dimensions and levels. An alternative approach is to ask people directly about the relative importance to them of the dimensions, levels and interactions between them. This paper describes a new stated preference approach for directly eliciting personal utility functions (PUFs), and reports a pilot study to test its feasibility for valuing the EQ-5D., Methods: A questionnaire was developed, designed to directly elicit PUFs from general public respondents via computer-assisted personal interviews, with a focus on helping respondents to reflect and deliberate on their preferences. The questionnaire was piloted in England., Results: Seventy-six interviews were conducted in December 2015. Overall, pain/discomfort and mobility were found to be the most important of the EQ-5D dimensions. The ratings for intermediate improvements in each dimension show heterogeneity, both within and between respondents. Almost a quarter of respondents indicated that no EQ-5D health states are worse than dead., Discussion: The PUF approach appears to be feasible, and has the potential to yield meaningful, well-informed preference data from respondents that can be aggregated to yield a value set for the EQ-5D. A deliberative approach to health state valuation also has the potential to complement and develop existing valuation methods. Further refinement of some elements of the approach is required.

Background: Different countries have different preferences regarding health, and there are different value sets for popular preference-based measures across different countries. However, the cost of collecting data to generate country-specific value sets can be prohibitive for countries with smaller population size or low- and middle-income countries (LMIC). This paper explores whether existing preference weights could be modelled alongside a small own country valuation study to generate representative estimates. This is explored using a case study modelling UK data alongside smaller US samples to generate US estimates., Methods: We analyse EQ-5D valuation data derived from representative samples of the US and UK populations using time trade-off to value 42 health states. A nonparametric Bayesian model was applied to estimate a US value set using the full UK dataset and subsets of the US dataset for 10, 15, 20 and 25 health states. Estimates are compared to a US value set estimated using US values alone using mean predictions and root mean square error., Results: The results suggest that using US data elicited for 20 health states alongside the existing UK data produces similar predicted mean valuations and RMSE as the US value set, while 25 health states produce the exact features., Conclusions: The promising results suggest that existing preference data could be combined with a small valuation study in a new country to generate preference weights, making own country value sets more achievable for LMIC. Further research is encouraged.

This paper proposes an aggregable family of multidimensional concentration indices which is characterized in order to be consistent with a property of exogenous risk factors, i.e. health risks for which agents are not responsible for. It is shown that those indices are of interest when individuals face different risk factors, whereas traditional indices fail to deal with heterogeneous agents. In this respect, necessary and suficient conditions are stated in order to rank two health distributions thanks to the generalized concentration curves. An illustration is performed using a sample of individuals living in Luxembourg aged 50 and older.

Recent years have seen increasing interest in the use of ordinal methods to elicit health state utility values as an alternative to conventional methods such as standard gamble and time trade-off (TTO). However, in order to use these ordinal methods to produce health state values for use in cost-effectiveness analysis using cost per quality adjusted life year (QALY) analysis, these values must be anchored on the full health-dead scale. The paper reports on two feasibility studies that use two approaches to anchor health state utility values derived from discrete choice data on the full health-dead scale: normalising using (1) the TTO value of the worst state and (2) the coefficient on the 'dead' dummy variable. Health state utility values obtained using rank and discrete choice data are compared to more commonly used TTO utility values for two condition-specific preference-based measures; asthma and overactive bladder. Ordinal methods were found to offer a promising alternative to conventional cardinal methods of standard gamble and TTO. There remains a large and important research agenda to address.

Visual field examination with fixed stimuli was first realized in manual static profile perimetry. The transition from a linear stimulus alignment along a profile section towards a two-dimensional arrangement introduced the era of static grid perimetry. Application of computer technology nowadays allows automation and standardization of this procedure, which enables the examiner to select the necessary visual field area, the adequate grid, and the optimal strategy for an estimation of differential luminance sensitivity. Furthermore, the computer independently takes over the recording, visualization, and processing of the perimetric procedure. This contribution discusses conventional static visual field examinations since these are widely used, easily accessible, well established for practical application, and standardized. This paper (part 4) explicitly focuses on the correct interpretation of automated static strategies of visual field examinations. Furthermore the classification and scoring of visual field defects as well as quality control, progression analysis, and perimetry in childhood are addressed. This manuscript is based on three preceding parts, which were published in previous issues of this journal [27, 28, 29].

This paper describes the use of urological laparoscopy in borderline patients, focussing on geriatric patients and those with renal failure. Laparoscopy must not only be feasible but also at least as effective concerning operative and postoperative parameters when compared to standard open surgery. For laparoscopic nephrectomy most of these factors have tested positive. However, only a few papers have been published concerning borderline patients. In some cases the pneumoperitoneum may not be suitable for borderline patients and open operative techniques are preferred. Apart from this, the current literature supports the effectiveness of laparoscopy even when certain risk factors are present. Especially borderline patients can benefit from the laparoscopic approach for nephrectomy. Although data are scarce concerning other laparoscopic procedures in borderline patients, the results of laparoscopic nephrectomy should probably apply to other laparoscopic procedures.