Combining Rasch and cluster analysis: a novel method for developing rheumatoid arthritis states for use in valuation studies

Purpose: Health states that describe an investigated condition are a crucial component of valuation studies. The health states need to be distinct, comprehensible, and data-driven. The objective of this study was to describe a novel application of Rasch and cluster analyses in the development of three rheumatoid arthritis health states. Methods: The Stanford Health Assessment Questionnaire (HAQ) was subjected to Rasch analysis to select the items that best represent disability. K-means cluster analysis produced health states with the levels of the selected items. The pain and discomfort domain from the EuroQol-5D was incorporated at the final stage. Results: The results demonstrate a methodology for reducing a dataset containing individual disease-specific scores to generate health states. The four selected HAQ items were bending down, climbing steps, lifting a cup to your mouth, and standing up from a chair. Conclusions: Overall, the combined use of Rasch and cluster analysis has proved to be an effective technique for identifying the most important items and levels for the construction of health states

Combining Rasch and cluster analysis: a novel method for developing rheumatoid arthritis states for use in valuation studies

Purpose: Health states that describe an investigated condition are a crucial component of valuation studies. The health states need to be distinct, comprehensible, and data-driven. The objective of this study was to describe a novel application of Rasch and cluster analyses in the development of three rheumatoid arthritis health states. Methods: The Stanford Health Assessment Questionnaire (HAQ) was subjected to Rasch analysis to select the items that best represent disability. K-means cluster analysis produced health states with the levels of the selected items. The pain and discomfort domain from the EuroQol-5D was incorporated at the final stage. Results: The results demonstrate a methodology for reducing a dataset containing individual disease-specific scores to generate health states. The four selected HAQ items were bending down, climbing steps, lifting a cup to your mouth, and standing up from a chair. Conclusions: Overall, the combined use of Rasch and cluster analysis has proved to be an effective technique for identifying the most important items and levels for the construction of health states.health state; Rasch analysis; cluster analysis; quality of life; rheumatoid arthritis

A qualitative study exploring the general population's perception of rheumatoid arthritis after being informed about disease adaptation

Purpose: This study aimed to gain an understanding of what factors induce individuals to alter their opinions about a health condition after being informed about disease adaptation and being given time to reflect and deliberate on this information. Rheumatoid arthritis (RA) states are used as an illustration. Methods: Semi-structured interviews were conducted with 12 members of the general population. They completed two time trade-off exercises for three RA states and underwent an adaptation exercise (AE) which consisted of listening to recordings of patients discussing how they adapted to RA. Also included was a structured discussion to encourage the participant to reflect on how the patients have adapted. Participants were shown their own health state values, as well as patient values. Findings: After being informed about disease adaptation and reflecting on the information, participants were more likely to consider adaptation and alter their opinions of RA if they were able to empathise with the patients in the AE. This enabled individuals to feel that they could cope by reflecting on their experience of RA in family and friends, by drawing on others for support if they had RA, and by having a positive attitude towards life. Conclusions: The results demonstrate that there is a range of reasons for which people change their perceptions about RA; this requires further exploration

A qualitative study exploring the general population’s perception of rheumatoid arthritis after being informed about disease adaptation

Purpose: This study aimed to gain an understanding of what factors induce individuals to alter their opinions about a health condition after being informed about disease adaptation and being given time to reflect and deliberate on this information. Rheumatoid arthritis (RA) states are used as an illustration. Methods: Semi-structured interviews were conducted with 12 members of the general population. They completed two time trade-off exercises for three RA states and underwent an adaptation exercise (AE) which consisted of listening to recordings of patients discussing how they adapted to RA. Also included was a structured discussion to encourage the participant to reflect on how the patients have adapted. Participants were shown their own health state values, as well as patient values. Findings: After being informed about disease adaptation and reflecting on the information, participants were more likely to consider adaptation and alter their opinions of RA if they were able to empathise with the patients in the AE. This enabled individuals to feel that they could cope by reflecting on their experience of RA in family and friends, by drawing on others for support if they had RA, and by having a positive attitude towards life. Conclusions: The results demonstrate that there is a range of reasons for which people change their perceptions about RA; this requires further exploration.health state valuation; qualitative research; quality of life; disease adaptation

A qualitative study exploring the general population's perception of rheumatoid arthritis after being informed about disease adaptation

Purpose: This study aimed to gain an understanding of what factors induce individuals to alter their opinions about a health condition after being informed about disease adaptation and being given time to reflect and deliberate on this information. Rheumatoid arthritis (RA) states are used as an illustration. Methods: Semi-structured interviews were conducted with 12 members of the general population. They completed two time trade-off exercises for three RA states and underwent an adaptation exercise (AE) which consisted of listening to recordings of patients discussing how they adapted to RA. Also included was a structured discussion to encourage the participant to reflect on how the patients have adapted. Participants were shown their own health state values, as well as patient values. Findings: After being informed about disease adaptation and reflecting on the information, participants were more likely to consider adaptation and alter their opinions of RA if they were able to empathise with the patients in the AE. This enabled individuals to feel that they could cope by reflecting on their experience of RA in family and friends, by drawing on others for support if they had RA, and by having a positive attitude towards life. Conclusions: The results demonstrate that there is a range of reasons for which people change their perceptions about RA; this requires further exploration

Effects of motion on jet exhaust noise from aircraft

The various problems involved in the evaluation of the jet noise field prevailing between an observer on the ground and an aircraft in flight in a typical takeoff or landing approach pattern were studied. Areas examined include: (1) literature survey and preliminary investigation, (2) propagation effects, (3) source alteration effects, and (4) investigation of verification techniques. Sixteen problem areas were identified and studied. Six follow-up programs were recommended for further work. The results and the proposed follow-on programs provide a practical general technique for predicting flyover jet noise for conventional jet nozzles

Reflecteren en onderwijs: een taxonomie

Het onderscheid tussen reflecteren, denken, leren, en leren reflecteren is onduidelijk. Er zijn allerlei vormen van reflecteren. Het is moeilijk deze te ontwikkelen. Het probleem is dat onderwijsdoelen met betrekking tot reflecteren in termen van studentengedrag ontbreken. Daarom is een taxonomie van reflecteren ontwikkeld naar analogie van de taxonomie van Bloom. Hierdoor wordt duidelijker wat eenvoudige, en dus gemakkelijke, vormen van reflecteren zijn, en wat moeilijke. Onderwijsdoelen kunnen zo effectiever worden bepaald. Reflectieve opdrachten kunnen beter worden gericht op de gekozen onderwijsdoelen. Het begrip reflectie en de taxonomie van Bloom zijn geanalyseerd, om deze taxonomie te kunnen toepassen op reflecteren. Hierbij werd geabstraheerd van doel, inhoud, context, hulpmiddelen, en moment van reflecteren. Reflecteren wordt in dit artikel geoperationaliseerd als het beantwoorden van reflectieve vragen. Het resultaat is een taxonomie van reflectie. Het karakteristieke van reflectie dat naar voren komt is dat steeds twee gedachtes worden vergeleken

Temperature-dependent Fermi surface evolution in heavy fermion CeIrIn5

In Cerium-based heavy electron materials, the 4f electron's magnetic moments bind to the itinerant quasiparticles to form composite heavy quasiparticles at low temperature. The volume of the Fermi surfacein the Brillouin zone incorporates the moments to produce a "large FS" due to the Luttinger theorem. When the 4f electrons are localized free moments, a "small FS" is induced since it contains only broad bands of conduction spd electrons. We have addressed theoretically the evolution of the heavy fermion FS as a function of temperature, using a first principles dynamical mean-field theory (DMFT) approach combined with density functional theory (DFT+DMFT). We focus on the archetypical heavy electrons in CeIrIn5, which is believed to be near a quantum critical point. Upon cooling, both the quantum oscillation frequencies and cyclotron masses show logarithmic scaling behavior (~ ln(T_0/T)) with different characteristic temperatures T_0 = 130 and 50 K, respectively. The resistivity coherence peak observed at T ~ 50 K is the result of the competition between the binding of incoherent 4f electrons to the spd conduction electrons at Fermi level and the formation of coherent 4f electrons.Comment: 5 pages main article,3 figures for the main article, 2 page Supplementary information, 2 figures for the Supplementary information. Supplementary movie 1 and 2 are provided on the webpage(http://www-ph.postech.ac.kr/~win/supple.html