Users’ Guides to the Medical Literature
Encyclopedia
The Users’ Guides to the Medical Literature is a series of articles originally published in the Journal of the American Medical Association
, now rewritten and compiled in a textbook format. The guides provide practical, clinician-friendly advice on all aspects of evidence-based medicine
.
including Dr. David Sackett
prepared a series of articles to assist clinicians interpreting clinical research. These articles, introducing the term "critical appraisal", appeared in the Canadian Medical Association Journal
beginning in 1981 and were immensely popular.
In 1990 Dr. Gordon Guyatt
introduced the term "evidence-based medicine" to describe a paradigm shift in medical practice that stressed the role of rigorous, systematic evidence from clinical research in conjunction with patients’ values and preferences in clinical decision-making. A group of academic physicians subsequently formed the first international Evidence-based Medicine Working Group and published an article expanding on the concept of evidence-based medicine.
The Evidence-based Medicine Working Group decided to build on the popular series in the Canadian Medical Association Journal by creating a more practical approach to applying the medical literature
to clinical practice. Championed by Dr. Drummond Rennie, an editor of the Journal of the American Medical Association, the result was the Users' Guides. The guides originally consisted of 25 topics, covered in a series of 32 articles published in the Journal of the American Medical Association between 1993 and 2000, describing approaches to different types of medical questions and the study designs that may answer them.
The complete list is as follows:
Barratt, A. et al., 1999. Users’ Guides to the Medical Literature: XVII. How to Use Guidelines and Recommendations About Screening. JAMA, 281(21), pp.2029-2034. Available at: http://jama.ama-assn.org/cgi/doi/10.1001/jama.281.21.2029
Bucher, H.C. et al., 1999. Users’ Guides to the Medical Literature: XIX. Applying Clinical Trial Results; A. How to Use an Article Measuring the Effect of an Intervention on Surrogate End Points. JAMA, 282(8), pp.771-778. Available at: http://jama.ama-assn.org/cgi/doi/10.1001/jama.282.8.771.
Dans, A.L. et al., 1998. Users’ Guides to the Medical Literature: XIV. How to Decide on the Applicability of Clinical Trial Results to Your Patient. JAMA, 279(7), pp.545-549. Available at: http://jama.ama-assn.org/cgi/doi/10.1001/jama.279.7.545
Drummond, M.F. et al., 1997. Users’ guides to the medical literature. XIII. How to use an article on economic analysis of clinical practice. A. Are the results of the study valid? Evidence-Based Medicine Working Group. JAMA, 277(19), pp.1552-1557. Available at: http://jama.ama-assn.org.
GH, G. et al., 1995. Users’ guides to the medical literature, IX: a method for grading health care recommendations. JAMA, 274, pp.1800-1804.
Giacomini, M.K. & Cook, D.J., 2000. Users’ Guides to the Medical Literature: XXIII. Qualitative Research in Health Care A. Are the Results of the Study Valid? JAMA, 284(3), pp.357-362. Available at: http://jama.ama-assn.org/cgi/doi/10.1001/jama.284.3.357
Giacomini, M.K. & Cook, D.J., 2000. Users’ Guides to the Medical Literature: XXIII. Qualitative Research in Health Care B. What Are the Results and How Do They Help Me Care for My Patients? JAMA, 284(4), pp.478-482. Available at: http://jama.ama-assn.org/cgi/doi/10.1001/jama.284.4.478.
Guyatt, G., Sackett, D. & Cook, D., 1993. Users’ guides to the medical literature, II: how to use an article about therapy or prevention, A: are the results of the study valid? JAMA, 270, pp.2598-2601.
Guyatt, G., Sackett, D. & Cook, D., 1994. Users’ guides to the medical literature, II: how to use an article about therapy or prevention, B: what were the results and will they help me in caring for my patients? JAMA, 271, pp.59-63.
Guyatt, G.H. & Rennie, D., 1993. Users’ guides to the medical literature. JAMA, 270(17), pp.2096-2097. Available at: http://jama.ama-assn.org.
Guyatt, G.H. et al., 2000. Users’ Guides to the Medical Literature: XXV. Evidence-Based Medicine: Principles for Applying the Users' Guides to Patient Care. JAMA, 284(10), pp.1290-1296. Available at: http://jama.ama-assn.org/cgi/doi/10.1001/jama.284.10.1290.
Guyatt, G.H. et al., 1997. Users’ guides to the medical literature. XII. How to use articles about health-related quality of life. Evidence-Based Medicine Working Group. JAMA, 277(15), pp.1232-1237. Available at: http://jama.ama-assn.org.
Guyatt, G.H. et al., 1999. Users’ Guides to the Medical Literature: XVI. How to Use a Treatment Recommendation. JAMA, 281(19), pp.1836-1843. Available at: http://jama.ama-assn.org/cgi/doi/10.1001/jama.281.19.1836
Hayward, R.S. et al., 1995. Users’ guides to the medical literature. VIII. How to use clinical practice guidelines. A. Are the recommendations valid? The Evidence-Based Medicine Working Group. JAMA, 274(7), pp.570-574. Available at: http://jama.ama-assn.org.
Hunt, D.L., Jaeschke, R.Z. & McKibbon, K.A., 2000. Users’ Guides to the Medical Literature: XXI. Using Electronic Health Information Resources in Evidence-Based Practice. JAMA, 283(14), pp.1875-1879. Available at: http://jama.ama-assn.org/cgi/doi/10.1001/jama.283.14.1875
Jaeschke, R.Z., Guyatt, G.H. & Sackett, D.L., 1994. Users’ guides to the medical literature. III. How to use an article about a diagnostic test. A. Are the results of the study valid? Evidence-Based Medicine Working Group. JAMA, 271(5), pp.389-391. Available at: http://jama.ama-assn.org.
Jaeschke, R.Z., Guyatt, G.H. & Sackett, D.L., 1994. Users’ guides to the medical literature. III. How to use an article about a diagnostic test. B. What are the results and will they help me in caring for my patients? The Evidence-Based Medicine Working Group. JAMA, 271(9), pp.703-707. Available at: http://jama.ama-assn.org.
Laupacis, A et al., 1994. Users’ guides to the medical literature. V. How to use an article about prognosis. Evidence-Based Medicine Working Group. JAMA, 272(3), pp.234-237. Available at: http://jama.ama-assn.org.
Levine, M. et al., 1994. Users’ guides to the medical literature. IV. How to use an article about harm. Evidence-Based Medicine Working Group. JAMA, 271(20), pp.1615-1619. Available at: http://jama.ama-assn.org.
McAlister, F.A. et al., 1999. Users’ Guides to the Medical Literature: XIX. Applying Clinical Trial Results; B. Guidelines for Determining Whether a Drug Is Exerting (More Than) a Class Effect. JAMA, 282(14), pp.1371-1377. Available at: http://jama.ama-assn.org/cgi/doi/10.1001/jama.282.14.1371
McAlister, F.A. et al., 2000. Users’ Guides to the Medical Literature: XX. Integrating Research Evidence With the Care of the Individual Patient. JAMA, 283(21), pp.2829-2836. Available at: http://jama.ama-assn.org/cgi/doi/10.1001/jama.283.21.2829
McGinn, T.G. et al., 2000. Users’ Guides to the Medical Literature: XXII: How to Use Articles About Clinical Decision Rules. JAMA, 284(1), pp.79-84. Available at: http://jama.ama-assn.org/cgi/doi/10.1001/jama.284.1.79
Naylor, C.D. & Guyatt, G.H., 1996. Users’ guides to the medical literature. X. How to use an article reporting variations in the outcomes of health services. The Evidence-Based Medicine Working Group. JAMA, 275(7), pp.554-558. Available at: http://jama.ama-assn.org.
Naylor, C.D. & Guyatt, G.H., 1996. Users’ guides to the medical literature. XI. How to use an article about a clinical utilization review. Evidence-Based Medicine Working Group. JAMA, 275(18), pp.1435-1439. Available at: http://jama.ama-assn.org.
Oxman, A.D., Cook, D.J. & Guyatt, G.H., 1994. Users’ guides to the medical literature. VI. How to use an overview. Evidence-Based Medicine Working Group. JAMA, 272(17), pp.1367-1371. Available at: http://jama.ama-assn.org.
O’Brien, B.J. et al., 1997. Users’ guides to the medical literature. XIII. How to use an article on economic analysis of clinical practice. B. What are the results and will they help me in caring for my patients? Evidence-Based Medicine Working Group. JAMA, 277(22), pp.1802-1806. Available at: http://jama.ama-assn.org.
Randolph, A.G. et al., 1999. Users’ Guides to the Medical Literature: XVIII. How to Use an Article Evaluating the Clinical Impact of a Computer-Based Clinical Decision Support System. JAMA, 282(1), pp.67-74. Available at: http://jama.ama-assn.org/cgi/doi/10.1001/jama.282.1.67
Richardson, W.S. & Detsky, A.S., 1995. Users’ guides to the medical literature. VII. How to use a clinical decision analysis. A. Are the results of the study valid? Evidence-Based Medicine Working Group. JAMA, 273(16), pp.1292-1295. Available at: http://jama.ama-assn.org.
Richardson, W.S. & Detsky, A.S., 1995. Users’ guides to the medical literature. VII. How to use a clinical decision analysis. B. What are the results and will they help me in caring for my patients? Evidence Based Medicine Working Group. JAMA, 273(20), pp.1610-1613. Available at: http://jama.ama-assn.org.
Richardson, W.S. et al., 1999. Users’ Guides to the Medical Literature: XV. How to Use an Article About Disease Probability for Differential Diagnosis. JAMA, 281(13), pp.1214-1219. Available at: http://jama.ama-assn.org/cgi/doi/10.1001/jama.281.13.1214
Richardson, W.S. et al., 2000. Users’ Guides to the Medical Literature: XXIV. How to Use an Article on the Clinical Manifestations of Disease. JAMA, 284(7), pp.869-875. Available at: http://jama.ama-assn.org/cgi/doi/10.1001/jama.284.7.869
Wilson, M.C. et al., 1995. Users’ guides to the Medical Literature. VIII. How to use clinical practice guidelines. B. what are the recommendations and will they help you in caring for your patients? The Evidence-Based Medicine Working Group. JAMA, 274(20), pp.1630-1632. Available at: http://jama.ama-assn.org.
The books teach a systematic approach to reading and applying the medical literature to individual patient care. It focuses on three questions: 1. Whether new information is likely to be true, 2. What the information says about patient care, and 3. How the information can be used. To demonstrate the clinical relevance of the suggested approach, each section begins with a practical clinical scenario. The chapter is then structured around identifying the best available evidence and applying the three key questions to the evidence, in the context of the clinical scenario. Each chapter concludes with a resolution of the scenario.
Most of the book chapters are based on specific types of clinical questions, including questions of therapy, harm, diagnosis, and prognosis. Other chapters deal with general skills that are important for all clinical questions, such as “Finding the Evidence”, “Summarizing the Evidence”, and “Moving From Evidence to Action”. This highly structured format allows readers to quickly locate the information they need to incorporate EBM into their practice. While readers will enjoy reading the book from cover to cover, they need not do so – the Users’ Guides functions equally well as a reference book to be called upon as needed.
The Users’ Guides is also available in Web-based formats for clinicians who prefer electronic material. The website includes a large number of additional aids for the practice of EBM.
Readers of the British Medical Journal have ranked evidence-based medicine as one of the ten most important medical breakthroughs of the twentieth century. Clinicians who wish to understand the medical literature and use it effectively in solving patient problems must have a firm understanding of the principles of EBM. The Essentials Users’ Guides provides the optimal introduction to familiarize clinicians with the tools needed to practice EBM.
Journal of the American Medical Association
The Journal of the American Medical Association is a weekly, peer-reviewed, medical journal, published by the American Medical Association. Beginning in July 2011, the editor in chief will be Howard C. Bauchner, vice chairman of pediatrics at Boston University’s School of Medicine, replacing ...
, now rewritten and compiled in a textbook format. The guides provide practical, clinician-friendly advice on all aspects of evidence-based medicine
Evidence-based medicine
Evidence-based medicine or evidence-based practice aims to apply the best available evidence gained from the scientific method to clinical decision making. It seeks to assess the strength of evidence of the risks and benefits of treatments and diagnostic tests...
.
As articles
During the late 1970s a group of clinical epidemiologists at McMaster UniversityMcMaster University
McMaster University is a public research university whose main campus is located in Hamilton, Ontario, Canada. The main campus is located on of land in the residential neighbourhood of Westdale, adjacent to Hamilton's Royal Botanical Gardens...
including Dr. David Sackett
David Sackett
David Lawrence Sackett, OC, FRSC is a Canadian medical doctor and a pioneer in evidence-based medicine. He founded the first department of clinical epidemiology in Canada at McMaster University, and the Oxford Centre for Evidence-Based Medicine...
prepared a series of articles to assist clinicians interpreting clinical research. These articles, introducing the term "critical appraisal", appeared in the Canadian Medical Association Journal
Canadian Medical Association Journal
The Canadian Medical Association Journal is a general medical journal that is published biweekly by the Canadian Medical Association . It covers research and ideas aimed at improving health for people in Canada and globally. CMAJ publishes original clinical research, analyses and reviews, news,...
beginning in 1981 and were immensely popular.
In 1990 Dr. Gordon Guyatt
Gordon Guyatt
Gordon Henry Guyatt is a physician and Professor of Clinical Epidemiology & Biostatistics at McMaster University in Hamilton, Ontario. He is known for his work on evidence-based medicine, a term that first appeared in a paper he published. He has published over 450 peer-reviewed articles in...
introduced the term "evidence-based medicine" to describe a paradigm shift in medical practice that stressed the role of rigorous, systematic evidence from clinical research in conjunction with patients’ values and preferences in clinical decision-making. A group of academic physicians subsequently formed the first international Evidence-based Medicine Working Group and published an article expanding on the concept of evidence-based medicine.
The Evidence-based Medicine Working Group decided to build on the popular series in the Canadian Medical Association Journal by creating a more practical approach to applying the medical literature
Medical literature
Medical literature refers to articles in journals and texts in books devoted to the field of medicine.Contemporary and historic views regarding diagnosis, prognosis and treatment of medical conditions have been documented for thousands of years. The Edwin Smith papyrus is the first known medical...
to clinical practice. Championed by Dr. Drummond Rennie, an editor of the Journal of the American Medical Association, the result was the Users' Guides. The guides originally consisted of 25 topics, covered in a series of 32 articles published in the Journal of the American Medical Association between 1993 and 2000, describing approaches to different types of medical questions and the study designs that may answer them.
The complete list is as follows:
Barratt, A. et al., 1999. Users’ Guides to the Medical Literature: XVII. How to Use Guidelines and Recommendations About Screening. JAMA, 281(21), pp.2029-2034. Available at: http://jama.ama-assn.org/cgi/doi/10.1001/jama.281.21.2029
Bucher, H.C. et al., 1999. Users’ Guides to the Medical Literature: XIX. Applying Clinical Trial Results; A. How to Use an Article Measuring the Effect of an Intervention on Surrogate End Points. JAMA, 282(8), pp.771-778. Available at: http://jama.ama-assn.org/cgi/doi/10.1001/jama.282.8.771.
Dans, A.L. et al., 1998. Users’ Guides to the Medical Literature: XIV. How to Decide on the Applicability of Clinical Trial Results to Your Patient. JAMA, 279(7), pp.545-549. Available at: http://jama.ama-assn.org/cgi/doi/10.1001/jama.279.7.545
Drummond, M.F. et al., 1997. Users’ guides to the medical literature. XIII. How to use an article on economic analysis of clinical practice. A. Are the results of the study valid? Evidence-Based Medicine Working Group. JAMA, 277(19), pp.1552-1557. Available at: http://jama.ama-assn.org.
GH, G. et al., 1995. Users’ guides to the medical literature, IX: a method for grading health care recommendations. JAMA, 274, pp.1800-1804.
Giacomini, M.K. & Cook, D.J., 2000. Users’ Guides to the Medical Literature: XXIII. Qualitative Research in Health Care A. Are the Results of the Study Valid? JAMA, 284(3), pp.357-362. Available at: http://jama.ama-assn.org/cgi/doi/10.1001/jama.284.3.357
Giacomini, M.K. & Cook, D.J., 2000. Users’ Guides to the Medical Literature: XXIII. Qualitative Research in Health Care B. What Are the Results and How Do They Help Me Care for My Patients? JAMA, 284(4), pp.478-482. Available at: http://jama.ama-assn.org/cgi/doi/10.1001/jama.284.4.478.
Guyatt, G., Sackett, D. & Cook, D., 1993. Users’ guides to the medical literature, II: how to use an article about therapy or prevention, A: are the results of the study valid? JAMA, 270, pp.2598-2601.
Guyatt, G., Sackett, D. & Cook, D., 1994. Users’ guides to the medical literature, II: how to use an article about therapy or prevention, B: what were the results and will they help me in caring for my patients? JAMA, 271, pp.59-63.
Guyatt, G.H. & Rennie, D., 1993. Users’ guides to the medical literature. JAMA, 270(17), pp.2096-2097. Available at: http://jama.ama-assn.org.
Guyatt, G.H. et al., 2000. Users’ Guides to the Medical Literature: XXV. Evidence-Based Medicine: Principles for Applying the Users' Guides to Patient Care. JAMA, 284(10), pp.1290-1296. Available at: http://jama.ama-assn.org/cgi/doi/10.1001/jama.284.10.1290.
Guyatt, G.H. et al., 1997. Users’ guides to the medical literature. XII. How to use articles about health-related quality of life. Evidence-Based Medicine Working Group. JAMA, 277(15), pp.1232-1237. Available at: http://jama.ama-assn.org.
Guyatt, G.H. et al., 1999. Users’ Guides to the Medical Literature: XVI. How to Use a Treatment Recommendation. JAMA, 281(19), pp.1836-1843. Available at: http://jama.ama-assn.org/cgi/doi/10.1001/jama.281.19.1836
Hayward, R.S. et al., 1995. Users’ guides to the medical literature. VIII. How to use clinical practice guidelines. A. Are the recommendations valid? The Evidence-Based Medicine Working Group. JAMA, 274(7), pp.570-574. Available at: http://jama.ama-assn.org.
Hunt, D.L., Jaeschke, R.Z. & McKibbon, K.A., 2000. Users’ Guides to the Medical Literature: XXI. Using Electronic Health Information Resources in Evidence-Based Practice. JAMA, 283(14), pp.1875-1879. Available at: http://jama.ama-assn.org/cgi/doi/10.1001/jama.283.14.1875
Jaeschke, R.Z., Guyatt, G.H. & Sackett, D.L., 1994. Users’ guides to the medical literature. III. How to use an article about a diagnostic test. A. Are the results of the study valid? Evidence-Based Medicine Working Group. JAMA, 271(5), pp.389-391. Available at: http://jama.ama-assn.org.
Jaeschke, R.Z., Guyatt, G.H. & Sackett, D.L., 1994. Users’ guides to the medical literature. III. How to use an article about a diagnostic test. B. What are the results and will they help me in caring for my patients? The Evidence-Based Medicine Working Group. JAMA, 271(9), pp.703-707. Available at: http://jama.ama-assn.org.
Laupacis, A et al., 1994. Users’ guides to the medical literature. V. How to use an article about prognosis. Evidence-Based Medicine Working Group. JAMA, 272(3), pp.234-237. Available at: http://jama.ama-assn.org.
Levine, M. et al., 1994. Users’ guides to the medical literature. IV. How to use an article about harm. Evidence-Based Medicine Working Group. JAMA, 271(20), pp.1615-1619. Available at: http://jama.ama-assn.org.
McAlister, F.A. et al., 1999. Users’ Guides to the Medical Literature: XIX. Applying Clinical Trial Results; B. Guidelines for Determining Whether a Drug Is Exerting (More Than) a Class Effect. JAMA, 282(14), pp.1371-1377. Available at: http://jama.ama-assn.org/cgi/doi/10.1001/jama.282.14.1371
McAlister, F.A. et al., 2000. Users’ Guides to the Medical Literature: XX. Integrating Research Evidence With the Care of the Individual Patient. JAMA, 283(21), pp.2829-2836. Available at: http://jama.ama-assn.org/cgi/doi/10.1001/jama.283.21.2829
McGinn, T.G. et al., 2000. Users’ Guides to the Medical Literature: XXII: How to Use Articles About Clinical Decision Rules. JAMA, 284(1), pp.79-84. Available at: http://jama.ama-assn.org/cgi/doi/10.1001/jama.284.1.79
Naylor, C.D. & Guyatt, G.H., 1996. Users’ guides to the medical literature. X. How to use an article reporting variations in the outcomes of health services. The Evidence-Based Medicine Working Group. JAMA, 275(7), pp.554-558. Available at: http://jama.ama-assn.org.
Naylor, C.D. & Guyatt, G.H., 1996. Users’ guides to the medical literature. XI. How to use an article about a clinical utilization review. Evidence-Based Medicine Working Group. JAMA, 275(18), pp.1435-1439. Available at: http://jama.ama-assn.org.
Oxman, A.D., Cook, D.J. & Guyatt, G.H., 1994. Users’ guides to the medical literature. VI. How to use an overview. Evidence-Based Medicine Working Group. JAMA, 272(17), pp.1367-1371. Available at: http://jama.ama-assn.org.
O’Brien, B.J. et al., 1997. Users’ guides to the medical literature. XIII. How to use an article on economic analysis of clinical practice. B. What are the results and will they help me in caring for my patients? Evidence-Based Medicine Working Group. JAMA, 277(22), pp.1802-1806. Available at: http://jama.ama-assn.org.
Randolph, A.G. et al., 1999. Users’ Guides to the Medical Literature: XVIII. How to Use an Article Evaluating the Clinical Impact of a Computer-Based Clinical Decision Support System. JAMA, 282(1), pp.67-74. Available at: http://jama.ama-assn.org/cgi/doi/10.1001/jama.282.1.67
Richardson, W.S. & Detsky, A.S., 1995. Users’ guides to the medical literature. VII. How to use a clinical decision analysis. A. Are the results of the study valid? Evidence-Based Medicine Working Group. JAMA, 273(16), pp.1292-1295. Available at: http://jama.ama-assn.org.
Richardson, W.S. & Detsky, A.S., 1995. Users’ guides to the medical literature. VII. How to use a clinical decision analysis. B. What are the results and will they help me in caring for my patients? Evidence Based Medicine Working Group. JAMA, 273(20), pp.1610-1613. Available at: http://jama.ama-assn.org.
Richardson, W.S. et al., 1999. Users’ Guides to the Medical Literature: XV. How to Use an Article About Disease Probability for Differential Diagnosis. JAMA, 281(13), pp.1214-1219. Available at: http://jama.ama-assn.org/cgi/doi/10.1001/jama.281.13.1214
Richardson, W.S. et al., 2000. Users’ Guides to the Medical Literature: XXIV. How to Use an Article on the Clinical Manifestations of Disease. JAMA, 284(7), pp.869-875. Available at: http://jama.ama-assn.org/cgi/doi/10.1001/jama.284.7.869
Wilson, M.C. et al., 1995. Users’ guides to the Medical Literature. VIII. How to use clinical practice guidelines. B. what are the recommendations and will they help you in caring for your patients? The Evidence-Based Medicine Working Group. JAMA, 274(20), pp.1630-1632. Available at: http://jama.ama-assn.org.
As books
Dr. Guyatt and Dr. Rennie edited the articles and compiled them to form a book titled Users' Guides to the Medical Literature: A Manual for Evidence-Based Clinical Practice. The Users' Guides now come in two book versions. The Essentials introduces the concepts of evidence-based medicine (EBM), with which every practicing clinician should be familiar. The Manual provides a comprehensive, in-depth exploration of the EBM concepts for clinicians seeking a deeper understanding of EBM, or for those who wish to role-model and teach EBM.The books teach a systematic approach to reading and applying the medical literature to individual patient care. It focuses on three questions: 1. Whether new information is likely to be true, 2. What the information says about patient care, and 3. How the information can be used. To demonstrate the clinical relevance of the suggested approach, each section begins with a practical clinical scenario. The chapter is then structured around identifying the best available evidence and applying the three key questions to the evidence, in the context of the clinical scenario. Each chapter concludes with a resolution of the scenario.
Most of the book chapters are based on specific types of clinical questions, including questions of therapy, harm, diagnosis, and prognosis. Other chapters deal with general skills that are important for all clinical questions, such as “Finding the Evidence”, “Summarizing the Evidence”, and “Moving From Evidence to Action”. This highly structured format allows readers to quickly locate the information they need to incorporate EBM into their practice. While readers will enjoy reading the book from cover to cover, they need not do so – the Users’ Guides functions equally well as a reference book to be called upon as needed.
The Users’ Guides is also available in Web-based formats for clinicians who prefer electronic material. The website includes a large number of additional aids for the practice of EBM.
Readers of the British Medical Journal have ranked evidence-based medicine as one of the ten most important medical breakthroughs of the twentieth century. Clinicians who wish to understand the medical literature and use it effectively in solving patient problems must have a firm understanding of the principles of EBM. The Essentials Users’ Guides provides the optimal introduction to familiarize clinicians with the tools needed to practice EBM.