Bias and Confounding
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The Status Quo Bias and Decisions to Withdraw Life-Sustaining Treatment
HUMANITIES | MEDICINE AND SOCIETY The status quo bias and decisions to withdraw life-sustaining treatment n Cite as: CMAJ 2018 March 5;190:E265-7. doi: 10.1503/cmaj.171005 t’s not uncommon for physicians and impasse. One factor that hasn’t been host of psychological phenomena that surrogate decision-makers to disagree studied yet is the role that cognitive cause people to make irrational deci- about life-sustaining treatment for biases might play in surrogate decision- sions, referred to as “cognitive biases.” Iincapacitated patients. Several studies making regarding withdrawal of life- One cognitive bias that is particularly show physicians perceive that nonbenefi- sustaining treatment. Understanding the worth exploring in the context of surrogate cial treatment is provided quite frequently role that these biases might play may decisions regarding life-sustaining treat- in their intensive care units. Palda and col- help improve communication between ment is the status quo bias. This bias, a leagues,1 for example, found that 87% of clinicians and surrogates when these con- decision-maker’s preference for the cur- physicians believed that futile treatment flicts arise. rent state of affairs,3 has been shown to had been provided in their ICU within the influence decision-making in a wide array previous year. (The authors in this study Status quo bias of contexts. For example, it has been cited equated “futile” with “nonbeneficial,” The classic model of human decision- as a mechanism to explain patient inertia defined as a treatment “that offers no rea- making is the rational choice or “rational (why patients have difficulty changing sonable hope of recovery or improvement, actor” model, the view that human beings their behaviour to improve their health), or because the patient is permanently will choose the option that has the best low organ-donation rates, low retirement- unable to experience any benefit.”) chance of satisfying their preferences. -
(HCW) Surveys in Humanitarian Contexts in Lmics
Analytics for Operations working group GUIDANCE BRIEF Guidance for Health Care Worker (HCW) Surveys in humanitarian contexts in LMICs Developed by the Analytics for Operations Working Group to support those working with communities and healthcare workers in humanitarian and emergency contexts. This document has been developed for response actors working in humanitarian contexts who seek rapid approaches to gathering evidence about the experience of healthcare workers, and the communities of which they are a part. Understanding healthcare worker experience is critical to inform and guide humanitarian programming and effective strategies to promote IPC, identify psychosocial support needs. This evidence also informs humanitarian programming that interacts with HCWs and facilities such as nutrition, health reinforcement, communication, SGBV and gender. In low- and middle-income countries (LMIC), healthcare workers (HCW) are often faced with limited resources, equipment, performance support and even formal training to provide the life-saving work expected of them. In humanitarian contexts1, where human resources are also scarce, HCWs may comprise formally trained doctors, nurses, pharmacists, dentists, allied health professionals etc. as well as community members who perform formal health worker related duties with little or no trainingi. These HCWs frequently work in contexts of multiple public health crises, including COVID-19. Their work will be affected by availability of resources (limited supplies, materials), behaviour and emotion (fear), flows of (mis)information (e.g. understanding of expected infection prevention and control (IPC) measures) or services (healthcare policies, services and use). Multiple factors can therefore impact patients, HCWs and their families, not only in terms of risk of exposure to COVID-19, but secondary health, socio-economic and psycho-social risks, as well as constraints that interrupt or hinder healthcare provision such as physical distancing practices. -
APPLICATION of the TAGUCHI METHOD to SENSITIVITY ANALYSIS of a MIDDLE- EAR FINITE-ELEMENT MODEL Li Qi1, Chadia S
APPLICATION OF THE TAGUCHI METHOD TO SENSITIVITY ANALYSIS OF A MIDDLE- EAR FINITE-ELEMENT MODEL Li Qi1, Chadia S. Mikhael1 and W. Robert J. Funnell1, 2 1 Department of BioMedical Engineering 2 Department of Otolaryngology McGill University Montréal, QC, Canada H3A 2B4 ABSTRACT difference in the model output due to the change in the input variable is referred to as the sensitivity. The Sensitivity analysis of a model is the investigation relative importance of parameters is judged based on of how outputs vary with changes of input parameters, the magnitude of the calculated sensitivity. The OFAT in order to identify the relative importance of method does not, however, take into account the parameters and to help in optimization of the model. possibility of interactions among parameters. Such The one-factor-at-a-time (OFAT) method has been interactions mean that the model sensitivity to one widely used for sensitivity analysis of middle-ear parameter can change depending on the values of models. The results of OFAT, however, are unreliable other parameters. if there are significant interactions among parameters. Alternatively, the full-factorial method permits the This paper incorporates the Taguchi method into the analysis of parameter interactions, but generally sensitivity analysis of a middle-ear finite-element requires a very large number of simulations. This can model. Two outputs, tympanic-membrane volume be impractical when individual simulations are time- displacement and stapes footplate displacement, are consuming. A more practical approach is the Taguchi measured. Nine input parameters and four possible method, which is commonly used in industry. It interactions are investigated for two model outputs. -
How Differences Between Online and Offline Interaction Influence Social
Available online at www.sciencedirect.com ScienceDirect Two social lives: How differences between online and offline interaction influence social outcomes 1 2 Alicea Lieberman and Juliana Schroeder For hundreds of thousands of years, humans only Facebook users,75% ofwhom report checking the platform communicated in person, but in just the past fifty years they daily [2]. Among teenagers, 95% report using smartphones have started also communicating online. Today, people and 45%reportbeingonline‘constantly’[2].Thisshiftfrom communicate more online than offline. What does this shift offline to online socializing has meaningful and measurable mean for human social life? We identify four structural consequences for every aspect of human interaction, from differences between online (versus offline) interaction: (1) fewer how people form impressions of one another, to how they nonverbal cues, (2) greater anonymity, (3) more opportunity to treat each other, to the breadth and depth of their connec- form new social ties and bolster weak ties, and (4) wider tion. The current article proposes a new framework to dissemination of information. Each of these differences identify, understand, and study these consequences, underlies systematic psychological and behavioral highlighting promising avenues for future research. consequences. Online and offline lives often intersect; we thus further review how online engagement can (1) disrupt or (2) Structural differences between online and enhance offline interaction. This work provides a useful offline interaction -
Journal of Clinical Trails Market Analysis Advances in Clinical Research and Clinical Trials 2020
Journal of Clinical Trails Market Analysis Advances in Clinical Research and Clinical Trials 2020 Raymond Chong The research report on Global Clinical Trials Market 2019 Other prominent players in the value chain include Mednet keenly analyzes significant features of the industry. The Solutions, Arisglobal, eClinForce Inc., DZS Software Solutions, DSG, analysis servers market size, latest trends, drivers, threats, Inc., Guger Technologies Inc., ICON, Plc., ChemWare Inc., and opportunities, as well as key market segments. It is based on iWeb Technologies Limited. past data and present market needs. Also, involve distinct business approaches accepted by the decision makers. Those intensify growth and make a remarkable stand in the industry. The Clinical Trials market will grow with a significant CAGR between 2019 to 2028. The report segregates the complete market on the basis of key players, geographical areas, and segments. Increasing demand for new medical equipments and medicines among end users, coupled with growing investment for research and development activities for development of effective medicines are major factors driving growth of the global clinical trials market. In addition, increasing number of individuals suffering from chronic diseases as well as changing The clinical trials market is projected to arrive at USD 1.76 conditions and nature of certain types of chronic diseases is billion by 2025, from USD 1.04 billion in 2017 growing at a another factor anticipated to support growth of the global CAGR of 6.7 percent from 2018 to 2025. An upcoming clinical trials market to significant extent. market report contains data for historic year 2016, and the base year of calculation is 2017. -
ARIADNE (Axion Resonant Interaction Detection Experiment): an NMR-Based Axion Search, Snowmass LOI
ARIADNE (Axion Resonant InterAction Detection Experiment): an NMR-based Axion Search, Snowmass LOI Andrew A. Geraci,∗ Aharon Kapitulnik, William Snow, Joshua C. Long, Chen-Yu Liu, Yannis Semertzidis, Yun Shin, and Asimina Arvanitaki (Dated: August 31, 2020) The Axion Resonant InterAction Detection Experiment (ARIADNE) is a collaborative effort to search for the QCD axion using techniques based on nuclear magnetic resonance. In the experiment, axions or axion-like particles would mediate short-range spin-dependent interactions between a laser-polarized 3He gas and a rotating (unpolarized) tungsten source mass, acting as a tiny, fictitious magnetic field. The experiment has the potential to probe deep within the theoretically interesting regime for the QCD axion in the mass range of 0.1- 10 meV, independently of cosmological assumptions. In this SNOWMASS LOI, we briefly describe this technique which covers a wide range of axion masses as well as discuss future prospects for improvements. Taken together with other existing and planned axion experi- ments, ARIADNE has the potential to completely explore the allowed parameter space for the QCD axion. A well-motivated example of a light mass pseudoscalar boson that can mediate new interactions or a “fifth-force” is the axion. The axion is a hypothetical particle that arises as a consequence of the Peccei-Quinn (PQ) mechanism to solve the strong CP problem of quantum chromodynamics (QCD)[1]. Axions have also been well motivated as a dark matter candidatedue to their \invisible" nature[2]. Axions can couple to fundamental fermions through a scalar vertex and a pseudoscalar vertex with very weak coupling strength. -
Removing Hidden Confounding by Experimental Grounding
Removing Hidden Confounding by Experimental Grounding Nathan Kallus Aahlad Manas Puli Uri Shalit Cornell University and Cornell Tech New York University Technion New York, NY New York, NY Haifa, Israel [email protected] [email protected] [email protected] Abstract Observational data is increasingly used as a means for making individual-level causal predictions and intervention recommendations. The foremost challenge of causal inference from observational data is hidden confounding, whose presence cannot be tested in data and can invalidate any causal conclusion. Experimental data does not suffer from confounding but is usually limited in both scope and scale. We introduce a novel method of using limited experimental data to correct the hidden confounding in causal effect models trained on larger observational data, even if the observational data does not fully overlap with the experimental data. Our method makes strictly weaker assumptions than existing approaches, and we prove conditions under which it yields a consistent estimator. We demonstrate our method’s efficacy using real-world data from a large educational experiment. 1 Introduction In domains such as healthcare, education, and marketing there is growing interest in using observa- tional data to draw causal conclusions about individual-level effects; for example, using electronic healthcare records to determine which patients should get what treatments, using school records to optimize educational policy interventions, or using past advertising campaign data to refine targeting and maximize lift. Observational datasets, due to their often very large number of samples and exhaustive scope (many measured covariates) in comparison to experimental datasets, offer a unique opportunity to uncover fine-grained effects that may apply to many target populations. -
Working Memory, Cognitive Miserliness and Logic As Predictors of Performance on the Cognitive Reflection Test
Working Memory, Cognitive Miserliness and Logic as Predictors of Performance on the Cognitive Reflection Test Edward J. N. Stupple ([email protected]) Centre for Psychological Research, University of Derby Kedleston Road, Derby. DE22 1GB Maggie Gale ([email protected]) Centre for Psychological Research, University of Derby Kedleston Road, Derby. DE22 1GB Christopher R. Richmond ([email protected]) Centre for Psychological Research, University of Derby Kedleston Road, Derby. DE22 1GB Abstract Most participants respond that the answer is 10 cents; however, a slower and more analytic approach to the The Cognitive Reflection Test (CRT) was devised to measure problem reveals the correct answer to be 5 cents. the inhibition of heuristic responses to favour analytic ones. The CRT has been a spectacular success, attracting more Toplak, West and Stanovich (2011) demonstrated that the than 100 citations in 2012 alone (Scopus). This may be in CRT was a powerful predictor of heuristics and biases task part due to the ease of administration; with only three items performance - proposing it as a metric of the cognitive miserliness central to dual process theories of thinking. This and no requirement for expensive equipment, the practical thesis was examined using reasoning response-times, advantages are considerable. There have, moreover, been normative responses from two reasoning tasks and working numerous correlates of the CRT demonstrated, from a wide memory capacity (WMC) to predict individual differences in range of tasks in the heuristics and biases literature (Toplak performance on the CRT. These data offered limited support et al., 2011) to risk aversion and SAT scores (Frederick, for the view of miserliness as the primary factor in the CRT. -
Guidance for Health Care Worker (HCW) Surveys in Humanitarian
Analytics for Operations & COVID-19 Research Roadmap Social Science working groups GUIDANCE BRIEF Guidance for Health Care Worker (HCW) Surveys in humanitarian contexts in LMICs Developed by the Analytics for Operations & COVID-19 Research Roadmap Social Science working groups to support those working with communities and healthcare workers in humanitarian and emergency contexts. This document has been developed for response actors working in humanitarian contexts who seek rapid approaches to gathering evidence about the experience of healthcare workers, and the communities of which they are a part. Understanding healthcare worker experience is critical to inform and guide humanitarian programming and effective strategies to promote IPC, identify psychosocial support needs. This evidence also informs humanitarian programming that interacts with HCWs and facilities such as nutrition, health reinforcement, communication, SGBV and gender. In low- and middle-income countries (LMIC), healthcare workers (HCW) are often faced with limited resources, equipment, performance support and even formal training to provide the life-saving work expected of them. In humanitarian contexts1, where human resources are also scarce, HCWs may comprise formally trained doctors, nurses, pharmacists, dentists, allied health professionals etc. as well as community members who perform formal health worker related duties with little or no trainingi. These HCWs frequently work in contexts of multiple public health crises, including COVID-19. Their work will be affected -
Using a Study on Arsenic Ingestion and Bladder Cancer As an Example How-Ran Guo1,2,3
Guo BMC Public Health 2011, 11:820 http://www.biomedcentral.com/1471-2458/11/820 RESEARCHARTICLE Open Access Age adjustment in ecological studies: using a study on arsenic ingestion and bladder cancer as an example How-Ran Guo1,2,3 Abstract Background: Despite its limitations, ecological study design is widely applied in epidemiology. In most cases, adjustment for age is necessary, but different methods may lead to different conclusions. To compare three methods of age adjustment, a study on the associations between arsenic in drinking water and incidence of bladder cancer in 243 townships in Taiwan was used as an example. Methods: A total of 3068 cases of bladder cancer, including 2276 men and 792 women, were identified during a ten-year study period in the study townships. Three methods were applied to analyze the same data set on the ten-year study period. The first (Direct Method) applied direct standardization to obtain standardized incidence rate and then used it as the dependent variable in the regression analysis. The second (Indirect Method) applied indirect standardization to obtain standardized incidence ratio and then used it as the dependent variable in the regression analysis instead. The third (Variable Method) used proportions of residents in different age groups as a part of the independent variables in the multiple regression models. Results: All three methods showed a statistically significant positive association between arsenic exposure above 0.64 mg/L and incidence of bladder cancer in men and women, but different results were observed for the other exposure categories. In addition, the risk estimates obtained by different methods for the same exposure category were all different. -
Sensitivity and Specificity. Wikipedia. Last Modified on 16 November 2013
Sensitivity and specificity - Wikipedia, the free encyclopedia Create account Log in Article Talk Read Edit View Sensitivity and specificity From Wikipedia, the free encyclopedia Main page Contents Sensitivity and specificity are statistical measures of the performance of a binary classification test, also known in statistics as Featured content classification function. Sensitivity (also called the true positive rate, or the recall rate in some fields) measures the proportion of Current events actual positives which are correctly identified as such (e.g. the percentage of sick people who are correctly identified as having Random article the condition). Specificity measures the proportion of negatives which are correctly identified as such (e.g. the percentage of Donate to Wikipedia healthy people who are correctly identified as not having the condition, sometimes called the true negative rate). These two measures are closely related to the concepts of type I and type II errors. A perfect predictor would be described as 100% Interaction sensitive (i.e. predicting all people from the sick group as sick) and 100% specific (i.e. not predicting anyone from the healthy Help group as sick); however, theoretically any predictor will possess a minimum error bound known as the Bayes error rate. About Wikipedia For any test, there is usually a trade-off between the measures. For example: in an airport security setting in which one is testing Community portal for potential threats to safety, scanners may be set to trigger on low-risk items like belt buckles and keys (low specificity), in Recent changes order to reduce the risk of missing objects that do pose a threat to the aircraft and those aboard (high sensitivity). -
Confounding Bias, Part I
ERIC NOTEBOOK SERIES Second Edition Confounding Bias, Part I Confounding is one type of Second Edition Authors: Confounding is also a form a systematic error that can occur in bias. Confounding is a bias because it Lorraine K. Alexander, DrPH epidemiologic studies. Other types of can result in a distortion in the systematic error such as information measure of association between an Brettania Lopes, MPH bias or selection bias are discussed exposure and health outcome. in other ERIC notebook issues. Kristen Ricchetti-Masterson, MSPH Confounding may be present in any Confounding is an important concept Karin B. Yeatts, PhD, MS study design (i.e., cohort, case-control, in epidemiology, because, if present, observational, ecological), primarily it can cause an over- or under- because it's not a result of the study estimate of the observed association design. However, of all study designs, between exposure and health ecological studies are the most outcome. The distortion introduced susceptible to confounding, because it by a confounding factor can be large, is more difficult to control for and it can even change the apparent confounders at the aggregate level of direction of an effect. However, data. In all other cases, as long as unlike selection and information there are available data on potential bias, it can be adjusted for in the confounders, they can be adjusted for analysis. during analysis. What is confounding? Confounding should be of concern Confounding is the distortion of the under the following conditions: association between an exposure 1. Evaluating an exposure-health and health outcome by an outcome association.