Development of a disease-specific version of the EQ-5D-5L for use in patients suffering from psoriasis: lessons learned from a feasibility study in the UK.

OBJECTIVES: The EuroQol five-dimensional (EQ-5D) questionnaire is a generic measure widely used for the assessment of health status. Research has suggested that it may be insensitive to the burdens associated with particular conditions. This study was designed to explore the feasibility of developing and valuing a disease-specific "bolt-on" version of the EQ-5D questionnaire for use in psoriasis. METHODS: A series of steps were undertaken to develop, test, and evaluate dimensions for a psoriasis-specific version of the EQ-5D questionnaire (hereafter referred to as the EQ-PSO questionnaire). Candidate dimensions were explored through a review of published literature, in-depth qualitative interviews with patients, and consultation with a clinical expert. A psychometric validation exercise was then undertaken to establish how well dimensions functioned. Two dimensions were selected for inclusion in a draft measure alongside the existing EQ-5D questionnaire dimensions: "skin irritation" and "self-confidence." Last, a time trade-off valuation exercise was conducted with 300 members of the UK general public to derive utilities for health states described by the measure. RESULTS: The psychometric analyses indicated that the two new candidate dimensions captured additional variance over and above the existing five dimensions. Data from the valuation exercise were analyzed by using different models. A collapsed random effects model was put forward as a parsimonious and accurate approach. Based on this model, estimated utilities ranged from 0.98 ± 0.02 for state "1111111" to 0.03 ± 0.29 for state "5555555." CONCLUSIONS: This study has developed the EQ-PSO questionnaire to support future psoriasis research and has informed the development of future bolt-on versions of the EQ-5D questionnaire.

Mapping Temperature Heterogeneities during Catalytic CO2 Methanation with Operando Luminescence Thermometry.

Controlling and understanding reaction temperature variations in catalytic processes are crucial for assessing the performance of a catalyst material. Local temperature measurements are challenging, however. Luminescence thermometry is a promising remote-sensing tool, but it is cross-sensitive to the optical properties of a sample and other external parameters. In this work, we measure spatial variations in the local temperature on the micrometer length scale during carbon dioxide (CO2) methanation over a TiO2-supported Ni catalyst and link them to variations in catalytic performance. We extract local temperatures from the temperature-dependent emission of Y2O3:Nd3+ particles, which are mixed with the CO2 methanation catalyst. Scanning, where a near-infrared laser locally excites the emitting Nd3+ ions, produces a temperature map with a micrometer pixel size. We first designed the Y2O3:Nd3+ particles for optimal temperature precision and characterized cross-sensitivity of the measured signal to parameters other than temperature, such as light absorption by the blackened sample due to coke deposition at elevated temperatures. Introducing reaction gases causes a local temperature increase of the catalyst of on average 6-25 K, increasing with the reactor set temperature in the range of 550-640 K. Pixel-to-pixel variations in the temperature increase show a standard deviation of up to 1.5 K, which are attributed to local variations in the catalytic reaction rate. Mapping and understanding such temperature variations are crucial for the optimization of overall catalyst performance on the nano- and macroscopic scale.

Disability adjusted life years and minimal disease: application of a preference-based relevance criterion to rank enteric pathogens.

BACKGROUND: Burden of disease estimates, which combine mortality and morbidity into a single measure, are used increasingly for priority setting in disease control, prevention and surveillance. However, because there is no clear exclusion criterion for highly prevalent minimal disease in burden of disease studies its application may be restricted. The aim of this study was to apply a newly developed relevance criterion based on preferences of a population panel, and to compare burden of disease estimates of five foodborne pathogens calculated with and without application of this criterion. METHODS: Preferences for twenty health states associated with foodborne disease were obtained from a population panel (n = 107) with the Visual Analogue Scale and the Time Trade-off (TTO) technique. The TTO preferences were used to derive the relevance criterion: if at least 50% of a panel of judges is willing to trade-off time in order to be restored to full health the health state is regarded as relevant, i.e. TTO median is greater than 0. Subsequently, the burden of disease of each of the five foodborne pathogens was calculated both with and without the relevance criterion. RESULTS: The panel ranked the health states consistently. Of the twenty health states, three did not meet the preference-based relevance criterion. Application of the relevance criterion reduced the burden of disease estimate of all five foodborne pathogens. The reduction was especially significant for norovirus and rotavirus, decreasing with 94% and 78% respectively. CONCLUSION: Individual preferences elicited with the TTO from a population panel can be used to empirically derive a relevance criterion for burden of disease estimates. Application of this preference-based relevance criterion results in considerable changes in ranking of foodborne pathogens.

Validity and reliability of the HeartQoL questionnaire in a large sample of stable coronary patients: The EUROASPIRE IV Study of the European Society of Cardiology.

BACKGROUND: The aim of this study was to investigate the validity and reliability of the HeartQoL instrument in a population of stable coronary patients. DESIGN: Analyses are based on the cross-sectional EUROASPIRE IV (EUROpean Action on Secondary and Primary prevention through Intervention to Reduce Events) survey. METHODS: Patients with a diagnosis of coronary heart disease were examined and interviewed 6 months to 3 years after their coronary event. During the interview patients were asked to fill out the HeartQoL health-related quality of life questionnaire as well as the EQ-5D and the hospital anxiety and depression scale questionnaire. Psychometric analyses assessing the reliability and validity of the HeartQoL instrument were performed. RESULTS: A total of 7449 patients completed the HeartQoL instrument. Cronbach's alpha indicated excellent internal consistency for the global HeartQoL scale (α = 0.92) and the physical subscale (α = 0.91) and good internal consistency for the emotional subscale (α = 0.87). Factor analysis confirmed the two-dimensional construct although mixed results were found regarding the model fit. Discriminative validity analysis confirmed better HeartQoL results in men, younger patients and higher educated persons. Likewise, convergent validity was confirmed with moderate to strong correlations among hypothesised constructs. CONCLUSION: Overall, psychometric analyses of the HeartQoL instrument in a population of patients with stable coronary heart disease showed good reliability and validity both at the European as well as the country-specific level. However, further research should focus on the responsiveness of the HeartQoL, the possible ceiling effect of the emotional subscale, construct validity and the minimal clinically important difference.

Preliminary evidence for an automatic link between sex and power among men who molest children.

Understanding critical motivational processes of sexual offenders may ultimately provide important clues to more effective treatments. Implicit, automatic cognitive processes have received minimal attention; however, a lexical decision experiment revealed automatic links between the concepts of power and sex among participants who self-reported attraction to sexual aggression. The current study replicates this experiment with a group of male child molesters and forensic and analogue controls. Subliminally presented sex words elicited a facilitation effect for power words among child molesters only; that is, sex to power associations were evident, as well as a trend for the reverse. These results provide preliminary evidence for an automatic sex-power association in child molesters and may point to a crucial pathological link in the cognitive schemata of sex offenders. As well, the current study suggests that paradigms from cognitive psychology may contribute to multimodal (risk) assessment of sexual offenders.

Introducing the composite time trade-off: a test of feasibility and face validity.

INTRODUCTION: This study was designed to test the feasibility and face validity of the composite time trade-off (composite TTO), a new approach to TTO allowing for a more consistent elicitation of negative health state values. METHODS: The new instrument combines a conventional TTO to elicit values for states regarded better than dead and a lead-time TTO for states worse than dead. RESULTS: A total of 121 participants completed the composite TTO for ten EQ-5D-5L health states. Mean values ranged from -0.104 for health state 53555 to 0.946 for 21111. The instructions were clear to 98 % of the respondents, and 95 % found the task easy to understand, indicating feasibility. Further, the average number of steps taken in the iteration procedure to achieve the point of indifference in the TTO and the average duration of each task were indicative of a deliberate cognitive process. CONCLUSION: Face validity was confirmed by the high mean values for the mild health states (>0.90) and low mean values for the severe states (<0.42). In conclusion, this study demonstrates the feasibility and face validity of the composite TTO in a face-to-face standardized computer-assisted interview setting.