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Concern has been raised regarding the use of simethicone, a de‐foaming agent, during endoscopic procedures. Following reports of simethicone residue in endoscope channels despite high level disinfection, an endoscope manufacturer recommended that it not be used due to concerns of biofilm formation and a possible increased risk of microorganism transmission. However, a detailed mucosal assessment is essential in performing high‐standard endoscopic procedures. This is impaired by bubbles within the gastrointestinal lumen. The Gastroenterological Society of Australia's Infection Control in Endoscopy Guidelines (ICEG) Committee conducted a literature search utilizing the MEDLINE database. Further references were sourced from published paper bibliographies. Following a review of the available evidence, and drawing on extensive clinical experience, the multidisciplinary ICEG committee considered the risks and benefits of simethicone use in formulating four recommendations. Published reports have documented residual liquid or crystalline simethicone in endoscope channels after high level disinfection. There are no data confirming that simethicone can be cleared from channels by brushing. Multiple series report benefits of simethicone use during gastroscopy and colonoscopy in improving mucosal assessment, adenoma detection rate, and reducing procedure time. There are no published reports of adverse events related specifically to the use of simethicone, delivered either orally or via any endoscope channel. An assessment of the risks and benefits supports the continued use of simethicone during endoscopic procedures. Strict adherence to instrument reprocessing protocols is essential.  相似文献   
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Discrete choice experiments (DCEs) are frequently used in health economics to measure preferences for nonmarket goods. Best–worst discrete choice experiment (BWDCE) has been proposed as a variant of the traditional “pick the best” approach. BWDCE, where participants choose the best and worst options, is argued to generate more precise preference estimates because of the additional information collected. However, the validity of the approach relies on two necessary conditions: (a) best and worst decisions provide similar information about preferences and (b) asking individuals to answer more than one choice question per task does not reduce data quality. Whether these conditions hold in empirical applications remains under researched. This is the first study to compare participants' choices across three experimental conditions: (a) BEST choices only, (b) WORST choices only, and (c) BEST and WORST choices (BWDCE). We find responses to worst choices are noisier. Implied preferences from the best only and worst only choices are qualitatively different, leading to different WTP values. Responses to BWDCE tasks have lower consistency, and respondents are more likely to use simplifying decision heuristics. We urge caution in using BWDCE as an alternative to the traditional “pick the best” DCE.  相似文献   
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Objectives: Black Caribbeans in the United States have been the victims of major discrimination (e.g. unfairly fired, denied a promotion, denied housing). What is not known is the degree to which they also experience more routine forms of everyday discrimination such as receiving poor restaurant service, being perceived as dishonest, and being followed in stores. This paper investigates the distribution and correlates of everyday discrimination among a national sample of black Caribbeans in the U.S.

Design: This analysis used the black Caribbean sub-sample (n?=?1,621) of the National Survey of American Life. Demographic and immigration status correlates of ten items from the Everyday Discrimination Scale were investigated: being treated with less courtesy, treated with less respect, receiving poor restaurant service, being perceived as not smart, being perceived as dishonest, being perceived as not as good as others, and being feared, insulted, harassed, or followed in stores.

Results: Roughly one out of ten black Caribbeans reported that, on a weekly basis, they were treated with less courtesy and other people acted as if they were better than them, were afraid of them, and as if they were not as smart. Everyday discrimination was more frequent for black Caribbeans who were male, never married, divorced/separated, earned higher incomes, and who were second or third generation immigrants. Black Caribbeans attributed the majority of the discrimination they experienced to their race.

Conclusion: To our knowledge, this is the first study to provide an in-depth investigation of everyday discrimination among the black Caribbean population. It provides the frequency, types and correlates of everyday discrimination reported by black Caribbeans in the United States. Understanding the frequency and types of discrimination is important because of the documented negative impacts of everyday discrimination on physical and mental health.  相似文献   

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