Author: Erwin B. Montgomery (Jr.)
Publisher:
ISBN: 0190912928
Category : Education
Languages : en
Pages : 297
Book Description
Modern medicine is one of humankind's greatest achievements.Yet today, frequent medical errors and irreproducibility in biomedical research suggest that tremendous challenges beset it. Understanding these challenges and trying to remedy them have driven considerable and thoughtful critical analyses, but the apparent intransigence of these problems suggests a different perspective is needed. Now more than ever, when we see options and opportunities for healthcare expanding while resources are diminishing, it is extremely important that healthcare professionals practice medicine wisely. In Medical Reasoning, neurologist Erwin B. Montgomery, Jr. offers a new and vital perspective. He begins with the idea that the need for certainty in medical decision-making has been the primary driving force in medical reasoning. Doctors must routinely confront countless manifestations of symptoms, diseases, or behaviors in their patients. Therefore, either there are as many different "diseases" as there are patients or some economical set of principles and facts can be combined to explain each patient's disease. The response to this epistemic conundrum has driven medicine throughout history: the challenge is to discover principles and facts and then to develop means to apply them to each unique patient in a manner that provides certainty. This book studies the nature of medical decision making systematically and rigorously in both an analytic and historical context, addressing medicine's unique need for certainty in the face of the enormous variety of diseases and in the manifestations of the same disease in different patients. The book also examines how the social, legal, and economic circumstances in which medical decision-making occurs greatly influence the nature of medical reasoning. Medical Reasoning is essential for those at the intersection of healthcare and philosophy.
Medical Reasoning
Author: Erwin B. Montgomery (Jr.)
Publisher:
ISBN: 0190912928
Category : Education
Languages : en
Pages : 297
Book Description
Modern medicine is one of humankind's greatest achievements.Yet today, frequent medical errors and irreproducibility in biomedical research suggest that tremendous challenges beset it. Understanding these challenges and trying to remedy them have driven considerable and thoughtful critical analyses, but the apparent intransigence of these problems suggests a different perspective is needed. Now more than ever, when we see options and opportunities for healthcare expanding while resources are diminishing, it is extremely important that healthcare professionals practice medicine wisely. In Medical Reasoning, neurologist Erwin B. Montgomery, Jr. offers a new and vital perspective. He begins with the idea that the need for certainty in medical decision-making has been the primary driving force in medical reasoning. Doctors must routinely confront countless manifestations of symptoms, diseases, or behaviors in their patients. Therefore, either there are as many different "diseases" as there are patients or some economical set of principles and facts can be combined to explain each patient's disease. The response to this epistemic conundrum has driven medicine throughout history: the challenge is to discover principles and facts and then to develop means to apply them to each unique patient in a manner that provides certainty. This book studies the nature of medical decision making systematically and rigorously in both an analytic and historical context, addressing medicine's unique need for certainty in the face of the enormous variety of diseases and in the manifestations of the same disease in different patients. The book also examines how the social, legal, and economic circumstances in which medical decision-making occurs greatly influence the nature of medical reasoning. Medical Reasoning is essential for those at the intersection of healthcare and philosophy.
Publisher:
ISBN: 0190912928
Category : Education
Languages : en
Pages : 297
Book Description
Modern medicine is one of humankind's greatest achievements.Yet today, frequent medical errors and irreproducibility in biomedical research suggest that tremendous challenges beset it. Understanding these challenges and trying to remedy them have driven considerable and thoughtful critical analyses, but the apparent intransigence of these problems suggests a different perspective is needed. Now more than ever, when we see options and opportunities for healthcare expanding while resources are diminishing, it is extremely important that healthcare professionals practice medicine wisely. In Medical Reasoning, neurologist Erwin B. Montgomery, Jr. offers a new and vital perspective. He begins with the idea that the need for certainty in medical decision-making has been the primary driving force in medical reasoning. Doctors must routinely confront countless manifestations of symptoms, diseases, or behaviors in their patients. Therefore, either there are as many different "diseases" as there are patients or some economical set of principles and facts can be combined to explain each patient's disease. The response to this epistemic conundrum has driven medicine throughout history: the challenge is to discover principles and facts and then to develop means to apply them to each unique patient in a manner that provides certainty. This book studies the nature of medical decision making systematically and rigorously in both an analytic and historical context, addressing medicine's unique need for certainty in the face of the enormous variety of diseases and in the manifestations of the same disease in different patients. The book also examines how the social, legal, and economic circumstances in which medical decision-making occurs greatly influence the nature of medical reasoning. Medical Reasoning is essential for those at the intersection of healthcare and philosophy.
Medical Problem Solving
Author: Arthur Shirle Elstein
Publisher:
ISBN:
Category : Medical
Languages : en
Pages : 360
Book Description
Publisher:
ISBN:
Category : Medical
Languages : en
Pages : 360
Book Description
Stochastic Medical Reasoning And Environmental Health Exposure
Author: George Christakos
Publisher: World Scientific
ISBN: 1908977515
Category : Science
Languages : en
Pages : 356
Book Description
The validity of certain critical reasoning steps carried out during or on the sidelines of the environmental science, public health survey, medical experiment, population risk assessment, or disease space-time mapping under conditions of in situ uncertainty and space-time heterogeneity, is often not given sufficient attention and may even be out of the investigator's line of thought. For example, the technical complexity of an environmental exposure experiment may overshadow the logical assumptions made when moving from one phase of the experiment to the next, or the study of population risk assessment may focus on analytical and computational matters, whereas methodological and cultural factors are neglected.This book helps health investigators structure their thinking so that they avoid logical mistakes and argument pitfalls, and also gain new insights about reality, improve their awareness of the environment and context within which one's thinking takes place.
Publisher: World Scientific
ISBN: 1908977515
Category : Science
Languages : en
Pages : 356
Book Description
The validity of certain critical reasoning steps carried out during or on the sidelines of the environmental science, public health survey, medical experiment, population risk assessment, or disease space-time mapping under conditions of in situ uncertainty and space-time heterogeneity, is often not given sufficient attention and may even be out of the investigator's line of thought. For example, the technical complexity of an environmental exposure experiment may overshadow the logical assumptions made when moving from one phase of the experiment to the next, or the study of population risk assessment may focus on analytical and computational matters, whereas methodological and cultural factors are neglected.This book helps health investigators structure their thinking so that they avoid logical mistakes and argument pitfalls, and also gain new insights about reality, improve their awareness of the environment and context within which one's thinking takes place.
Comparative Approaches to Medical Reasoning
Author: Maurice E. Cohen
Publisher: World Scientific
ISBN: 9789810221621
Category : Medical
Languages : en
Pages : 338
Book Description
This book focuses on approaches to computer-assisted medical decision-making. A unique feature of the book is that a specific problem in medical decision-making has been selected from the literature, with each contributed chapter presenting a different approach to the solution of the same problem. Theoretical foundations for each approach are provided, followed by practical application. Techniques include knowledge-based reasoning, neural network models, hybrid systems, reasoning with uncertainty, and fuzzy logic, among others. The goal is to supply the reader with a variety of theoretical techniques whose practical implementation can be clearly understood through the example. Using a single, concrete example to illustrate different theoretical approaches allows various techniques to be easily contrasted and permits the reader to determine which aspects are pertinent to specific types of applications. Although the methods are illustrated in a medical problem, they have wide applicability in numerous areas of decision-making.
Publisher: World Scientific
ISBN: 9789810221621
Category : Medical
Languages : en
Pages : 338
Book Description
This book focuses on approaches to computer-assisted medical decision-making. A unique feature of the book is that a specific problem in medical decision-making has been selected from the literature, with each contributed chapter presenting a different approach to the solution of the same problem. Theoretical foundations for each approach are provided, followed by practical application. Techniques include knowledge-based reasoning, neural network models, hybrid systems, reasoning with uncertainty, and fuzzy logic, among others. The goal is to supply the reader with a variety of theoretical techniques whose practical implementation can be clearly understood through the example. Using a single, concrete example to illustrate different theoretical approaches allows various techniques to be easily contrasted and permits the reader to determine which aspects are pertinent to specific types of applications. Although the methods are illustrated in a medical problem, they have wide applicability in numerous areas of decision-making.
Medical Decision Making
Author: Harold C. Sox
Publisher: John Wiley & Sons
ISBN: 1118341562
Category : Medical
Languages : en
Pages : 330
Book Description
Medical Decision Making provides clinicians with a powerful framework for helping patients make decisions that increase the likelihood that they will have the outcomes that are most consistent with their preferences. This new edition provides a thorough understanding of the key decision making infrastructure of clinical practice and explains the principles of medical decision making both for individual patients and the wider health care arena. It shows how to make the best clinical decisions based on the available evidence and how to use clinical guidelines and decision support systems in electronic medical records to shape practice guidelines and policies. Medical Decision Making is a valuable resource for all experienced and learning clinicians who wish to fully understand and apply decision modelling, enhance their practice and improve patient outcomes. “There is little doubt that in the future many clinical analyses will be based on the methods described in Medical Decision Making, and the book provides a basis for a critical appraisal of such policies.” - Jerome P. Kassirer M.D., Distinguished Professor, Tufts University School of Medicine, US and Visiting Professor, Stanford Medical School, US
Publisher: John Wiley & Sons
ISBN: 1118341562
Category : Medical
Languages : en
Pages : 330
Book Description
Medical Decision Making provides clinicians with a powerful framework for helping patients make decisions that increase the likelihood that they will have the outcomes that are most consistent with their preferences. This new edition provides a thorough understanding of the key decision making infrastructure of clinical practice and explains the principles of medical decision making both for individual patients and the wider health care arena. It shows how to make the best clinical decisions based on the available evidence and how to use clinical guidelines and decision support systems in electronic medical records to shape practice guidelines and policies. Medical Decision Making is a valuable resource for all experienced and learning clinicians who wish to fully understand and apply decision modelling, enhance their practice and improve patient outcomes. “There is little doubt that in the future many clinical analyses will be based on the methods described in Medical Decision Making, and the book provides a basis for a critical appraisal of such policies.” - Jerome P. Kassirer M.D., Distinguished Professor, Tufts University School of Medicine, US and Visiting Professor, Stanford Medical School, US
Teaching Clinical Reasoning
Author: Robert L. Trowbridge
Publisher: American College
ISBN: 9781938921056
Category : Clinical medicine
Languages : en
Pages : 270
Book Description
Chapter topics include: Clinical Reasoning and Diagnostic Error Theoretical Concepts to Consider in Providing Clinical Reasoning Instruction Developing a Curriculum in Clinical Reasoning Educational Approaches to Common Cognitive Errors General Teaching Techniques Assessment of Clinical Reasoning Faculty Development and Dissemination Lifelong Learning in Clinical Reasoning Remediation of Clinical Reasoning Novel Approaches and Future Directions Teaching Clinical Reasoning: Where do we go from here?
Publisher: American College
ISBN: 9781938921056
Category : Clinical medicine
Languages : en
Pages : 270
Book Description
Chapter topics include: Clinical Reasoning and Diagnostic Error Theoretical Concepts to Consider in Providing Clinical Reasoning Instruction Developing a Curriculum in Clinical Reasoning Educational Approaches to Common Cognitive Errors General Teaching Techniques Assessment of Clinical Reasoning Faculty Development and Dissemination Lifelong Learning in Clinical Reasoning Remediation of Clinical Reasoning Novel Approaches and Future Directions Teaching Clinical Reasoning: Where do we go from here?
Handbook of Research on Critical Thinking and Teacher Education Pedagogy
Author: Robinson, Sandra P.A.
Publisher: IGI Global
ISBN: 1522578307
Category : Education
Languages : en
Pages : 476
Book Description
Critical thinking is an essential skill for learners and teachers alike. Therefore, it is essential that educators be given practical strategies for improving their critical thinking skills as well as methods to effectively provide critical thinking skills to their students. The Handbook of Research on Critical Thinking and Teacher Education Pedagogy examines and explains how new strategies, methods, and techniques in critical thinking can be applied to classroom practice and professional development to improve teaching and learning in teacher education and make critical thinking a tangible objective in instruction. This critical scholarly publication helps to shift and advance the debate on how critical thinking should be taught and offers insights into the significance of critical thinking and its effective integration as a cornerstone of the educational system. Highlighting topics such as early childhood education, curriculum, and STEM education, this book is designed for teachers/instructors, instructional designers, education professionals, administrators, policymakers, researchers, and academicians.
Publisher: IGI Global
ISBN: 1522578307
Category : Education
Languages : en
Pages : 476
Book Description
Critical thinking is an essential skill for learners and teachers alike. Therefore, it is essential that educators be given practical strategies for improving their critical thinking skills as well as methods to effectively provide critical thinking skills to their students. The Handbook of Research on Critical Thinking and Teacher Education Pedagogy examines and explains how new strategies, methods, and techniques in critical thinking can be applied to classroom practice and professional development to improve teaching and learning in teacher education and make critical thinking a tangible objective in instruction. This critical scholarly publication helps to shift and advance the debate on how critical thinking should be taught and offers insights into the significance of critical thinking and its effective integration as a cornerstone of the educational system. Highlighting topics such as early childhood education, curriculum, and STEM education, this book is designed for teachers/instructors, instructional designers, education professionals, administrators, policymakers, researchers, and academicians.
Improving Diagnosis in Health Care
Author: National Academies of Sciences, Engineering, and Medicine
Publisher: National Academies Press
ISBN: 0309377722
Category : Medical
Languages : en
Pages : 473
Book Description
Getting the right diagnosis is a key aspect of health care - it provides an explanation of a patient's health problem and informs subsequent health care decisions. The diagnostic process is a complex, collaborative activity that involves clinical reasoning and information gathering to determine a patient's health problem. According to Improving Diagnosis in Health Care, diagnostic errors-inaccurate or delayed diagnoses-persist throughout all settings of care and continue to harm an unacceptable number of patients. It is likely that most people will experience at least one diagnostic error in their lifetime, sometimes with devastating consequences. Diagnostic errors may cause harm to patients by preventing or delaying appropriate treatment, providing unnecessary or harmful treatment, or resulting in psychological or financial repercussions. The committee concluded that improving the diagnostic process is not only possible, but also represents a moral, professional, and public health imperative. Improving Diagnosis in Health Care, a continuation of the landmark Institute of Medicine reports To Err Is Human (2000) and Crossing the Quality Chasm (2001), finds that diagnosis-and, in particular, the occurrence of diagnostic errorsâ€"has been largely unappreciated in efforts to improve the quality and safety of health care. Without a dedicated focus on improving diagnosis, diagnostic errors will likely worsen as the delivery of health care and the diagnostic process continue to increase in complexity. Just as the diagnostic process is a collaborative activity, improving diagnosis will require collaboration and a widespread commitment to change among health care professionals, health care organizations, patients and their families, researchers, and policy makers. The recommendations of Improving Diagnosis in Health Care contribute to the growing momentum for change in this crucial area of health care quality and safety.
Publisher: National Academies Press
ISBN: 0309377722
Category : Medical
Languages : en
Pages : 473
Book Description
Getting the right diagnosis is a key aspect of health care - it provides an explanation of a patient's health problem and informs subsequent health care decisions. The diagnostic process is a complex, collaborative activity that involves clinical reasoning and information gathering to determine a patient's health problem. According to Improving Diagnosis in Health Care, diagnostic errors-inaccurate or delayed diagnoses-persist throughout all settings of care and continue to harm an unacceptable number of patients. It is likely that most people will experience at least one diagnostic error in their lifetime, sometimes with devastating consequences. Diagnostic errors may cause harm to patients by preventing or delaying appropriate treatment, providing unnecessary or harmful treatment, or resulting in psychological or financial repercussions. The committee concluded that improving the diagnostic process is not only possible, but also represents a moral, professional, and public health imperative. Improving Diagnosis in Health Care, a continuation of the landmark Institute of Medicine reports To Err Is Human (2000) and Crossing the Quality Chasm (2001), finds that diagnosis-and, in particular, the occurrence of diagnostic errorsâ€"has been largely unappreciated in efforts to improve the quality and safety of health care. Without a dedicated focus on improving diagnosis, diagnostic errors will likely worsen as the delivery of health care and the diagnostic process continue to increase in complexity. Just as the diagnostic process is a collaborative activity, improving diagnosis will require collaboration and a widespread commitment to change among health care professionals, health care organizations, patients and their families, researchers, and policy makers. The recommendations of Improving Diagnosis in Health Care contribute to the growing momentum for change in this crucial area of health care quality and safety.
Clinical Inertia
Author: Gérard Reach
Publisher: Springer
ISBN: 3319098829
Category : Medical
Languages : en
Pages : 161
Book Description
Clinical practice guidelines were initially developed within the context of evidence-based medicine with the goal of putting medical research findings into practice. However, physicians do not always follow them, even when they seem to apply to the particular patient they have to treat. This phenomenon, known as clinical inertia, represents a significant obstacle to the efficiency of care and a major public health problem, the extent of which is demonstrated in this book. An analysis of its causes shows that it stems from a discrepancy between the objective, essentially statistical nature of evidence-based medicine on the one hand and the physician’s own complex, subjective view (referred to here as “medical reason”) on the other. This book proposes a critique of medical reason that may help to reconcile the principles of evidence-based medicine and individual practice. The author is a diabetologist and Professor of Endocrinology, Diabetology and Metabolic Diseases at Paris 13 University. He has authored several books, including one to be published by Springer (Philosophy and Medicine series) under the title: The Mental Mechanisms of Patient Adherence to Long Term Therapies, Mind and Care. , Diabetology and Metabolic Diseases at the Paris 13-University. He has also published Pourquoi Se soigne-t-on, Enquête sur la rationalité morale de l’observance (2007), Clinique de l’Observance, L’Exemple des diabètes (2006), and Une théorie du soin, Souci et amour face à la maladie (2010). An English adaptation of the first book is published by Springer (Philosophy and Medicine) under the title: The Mental Mechanisms of Patient Adherence to Long Term Therapies, Mind and Care.
Publisher: Springer
ISBN: 3319098829
Category : Medical
Languages : en
Pages : 161
Book Description
Clinical practice guidelines were initially developed within the context of evidence-based medicine with the goal of putting medical research findings into practice. However, physicians do not always follow them, even when they seem to apply to the particular patient they have to treat. This phenomenon, known as clinical inertia, represents a significant obstacle to the efficiency of care and a major public health problem, the extent of which is demonstrated in this book. An analysis of its causes shows that it stems from a discrepancy between the objective, essentially statistical nature of evidence-based medicine on the one hand and the physician’s own complex, subjective view (referred to here as “medical reason”) on the other. This book proposes a critique of medical reason that may help to reconcile the principles of evidence-based medicine and individual practice. The author is a diabetologist and Professor of Endocrinology, Diabetology and Metabolic Diseases at Paris 13 University. He has authored several books, including one to be published by Springer (Philosophy and Medicine series) under the title: The Mental Mechanisms of Patient Adherence to Long Term Therapies, Mind and Care. , Diabetology and Metabolic Diseases at the Paris 13-University. He has also published Pourquoi Se soigne-t-on, Enquête sur la rationalité morale de l’observance (2007), Clinique de l’Observance, L’Exemple des diabètes (2006), and Une théorie du soin, Souci et amour face à la maladie (2010). An English adaptation of the first book is published by Springer (Philosophy and Medicine) under the title: The Mental Mechanisms of Patient Adherence to Long Term Therapies, Mind and Care.
The Rational Clinical Examination: Evidence-Based Clinical Diagnosis
Author: David L. Simel
Publisher: McGraw Hill Professional
ISBN: 0071590315
Category : Medical
Languages : en
Pages : 940
Book Description
The ultimate guide to the evidence-based clinical encounter "This book is an excellent source of supported evidence that provides useful and clinically relevant information for the busy practitioner, student, resident, or educator who wants to hone skills of physical diagnosis. It provides a tool to improve patient care by using the history and physical examination items that have the most reliability and efficiency."--Annals of Internal Medicine "The evidence-based examination techniques put forth by Rational Clinical Examination is the sort that can be brought to bear on a daily basis – to save time, increase confidence in medical decisions, and help decrease unnecessary testing for conditions that do not require absolute diagnostic certainty. In the end, the whole of this book is greater than its parts and can serve as a worthy companion to a traditional manual of physical examination."--Baylor University Medical Center (BUMC)Proceedings 5 STAR DOODY'S REVIEW! "Physical diagnosis has been taught to every medical student but this evidence-based approach now shows us why, presenting one of medicine's most basic tenets in a new and challenging light. The format is extraordinary, taking previously published material and updating the pertinent evidence since the initial publication, affirming or questioning or refining the conclusions drawn from the data. "This is a book for everyone who has studied medicine and found themselves doubting what they have been taught over the years, not that they have been deluded, but that medical traditions have been unquestionably believed because there was no evidence to believe otherwise. The authors have uncovered the truth. "This extraordinary, one-of-a-kind book is a valuable addition to every medical library."--Doody's Review Service Completely updated with new literature analyses, here is a uniquely practical, clinically relevant approach to the use of evidence in the content of physical examination. Going far beyond the scope of traditional physical examination texts, this invaluable resource compiles and presents the evidence-based meanings of signs, symptoms, and results from physical examination maneuvers and other diagnostic studies. Page after page, you'll find a focus on actual clinical questions and presentations, making it an incomparably practical resource that you'll turn to again and again. Importantly, the high-yield content of The Rational Clinical Examination is significantly expanded and updated from the original JAMA articles, much of it published here for the first time. It all adds up to a definitive, ready-to-use clinical exam sourcebook that no student or clinician should be without. FEATURES Packed with updated, new, and previously unpublished information from the original JAMA articles Standardized template for every issue covered, including: Case Presentation; Why the Issue Is Clinically Important; Research and Statistical Methods Used to Find the Evidence Presented; The Sensitivity and Specificity of Each Key Result; Resolution of the Case Presentation; and the Clinical Bottom Line Completely updated with all-new literature searches and appraisals supplementing each chapter Full-color format with dynamic clinical illustrations and images Real-world focus on a specific clinical question in each chapter, reflecting the way clinicians approach the practice of evidence-based medicine More than 50 complete chapters on common and challenging clinical questions and patient presentations Also available: JAMAevidence.com, a new interactive database for the best practice of evidence based medicine
Publisher: McGraw Hill Professional
ISBN: 0071590315
Category : Medical
Languages : en
Pages : 940
Book Description
The ultimate guide to the evidence-based clinical encounter "This book is an excellent source of supported evidence that provides useful and clinically relevant information for the busy practitioner, student, resident, or educator who wants to hone skills of physical diagnosis. It provides a tool to improve patient care by using the history and physical examination items that have the most reliability and efficiency."--Annals of Internal Medicine "The evidence-based examination techniques put forth by Rational Clinical Examination is the sort that can be brought to bear on a daily basis – to save time, increase confidence in medical decisions, and help decrease unnecessary testing for conditions that do not require absolute diagnostic certainty. In the end, the whole of this book is greater than its parts and can serve as a worthy companion to a traditional manual of physical examination."--Baylor University Medical Center (BUMC)Proceedings 5 STAR DOODY'S REVIEW! "Physical diagnosis has been taught to every medical student but this evidence-based approach now shows us why, presenting one of medicine's most basic tenets in a new and challenging light. The format is extraordinary, taking previously published material and updating the pertinent evidence since the initial publication, affirming or questioning or refining the conclusions drawn from the data. "This is a book for everyone who has studied medicine and found themselves doubting what they have been taught over the years, not that they have been deluded, but that medical traditions have been unquestionably believed because there was no evidence to believe otherwise. The authors have uncovered the truth. "This extraordinary, one-of-a-kind book is a valuable addition to every medical library."--Doody's Review Service Completely updated with new literature analyses, here is a uniquely practical, clinically relevant approach to the use of evidence in the content of physical examination. Going far beyond the scope of traditional physical examination texts, this invaluable resource compiles and presents the evidence-based meanings of signs, symptoms, and results from physical examination maneuvers and other diagnostic studies. Page after page, you'll find a focus on actual clinical questions and presentations, making it an incomparably practical resource that you'll turn to again and again. Importantly, the high-yield content of The Rational Clinical Examination is significantly expanded and updated from the original JAMA articles, much of it published here for the first time. It all adds up to a definitive, ready-to-use clinical exam sourcebook that no student or clinician should be without. FEATURES Packed with updated, new, and previously unpublished information from the original JAMA articles Standardized template for every issue covered, including: Case Presentation; Why the Issue Is Clinically Important; Research and Statistical Methods Used to Find the Evidence Presented; The Sensitivity and Specificity of Each Key Result; Resolution of the Case Presentation; and the Clinical Bottom Line Completely updated with all-new literature searches and appraisals supplementing each chapter Full-color format with dynamic clinical illustrations and images Real-world focus on a specific clinical question in each chapter, reflecting the way clinicians approach the practice of evidence-based medicine More than 50 complete chapters on common and challenging clinical questions and patient presentations Also available: JAMAevidence.com, a new interactive database for the best practice of evidence based medicine