Abstract
Evidence-based medicine has become a magical term in human medicine, and is now the basis of each medical teaching program. Veterinary medicine follows hesitantly, but there is no doubt that logics instead of intuition will also become standard in veterinary medicine. Recently the first veterinary book on the subject has emerged meant for students and veterinarians and called ‘Handbook of Evidence-based Veterinary Medicine’ (Blackwell, 2003, ISBN 1-4051-0890-8). Evidence-based medicine has been defined for veterinary medicine by the authors as ‘the use of current best evidence in making clinical decisions’. The book has been written for veterinary surgeons in non-specialist, or non-referral practice. However, it has been written so well and provides so much directly applicable information about how to organise and use the ever-increasing stream of information that it is may also be recommended for reading by specialists.
The evidence-based way of making clinical decisions is opposed to the intuitive way, which is largely based on own experience, and often uses anecdotal information, common sense, pathophysiological assumptions, and uncontrolled external information. Evidence-based medicine uses mathematical analysis, and objective information as basis for choosing the best possible option for clinical decisions such as the choice of the most appropriate diagnostic test, the best treatment, prediction of success of intervention, expenses of a chosen strategy, and so on.
The book has been subdivided into a number of sections each dealing with a specific aspect of evidence-based veterinary medicine. First it is emphasised that a clinical problem should be rephrased and translated into logical questions (turning information needs into questions) in order to be able to unravel what one actually knows and which precise additional information is needed to answer the question, or solve the problem. Well-formulated questions are also the basis for searching in databases for the required evidence. The possible sources of information (journals, textbooks, and internet) are discussed with their advantages and drawbacks. There is also a list and short description of all useful internet databases for veterinarians. The next section (searching for evidence) explains how to use these databases efficiently to find available information or evidence. The use of Boolean logistic to define logical search questions which provide the information searched for as exactly as possible is clearly described and many examples for use in important databases such as Pubmed are given. In ‘Appraising the evidence’ the important statistical concepts are explained which are needed to judge the quality and relevance of the information found in the search action described before. Tools are given to judge the validity of published studies and the importance of the results so that the reader knows how to appraise the evidence as basis for making a decision. The chapter ‘Diagnosis’ describes the logical steps in the diagnostic process in which initial observations (history, physical examination) are weighed, turned into relevant differential diagnoses, leading to recognition of the additional information needed to differentiate between differential diagnosis. In one or more rounds of gaining and weighing information the final diagnosis is then selected. This is the way a diagnosis is made using the ‘problem-oriented approach’ which is taught in many veterinary schools in the USA and Europe. The chapter gives several strategies which can be used in this hypothetico-deductive way of reasoning. Computer assisted problem solving using programs as available on the internet sites of Provides (problem oriented veterinary information and decision system), Consultant, and others is dealt with. The final chapter is about decision analysis, and the use of models and economic parameters. Mathematical models are for example used to help in analysing and predicting infection dynamics in populations. The application of these models is mainly in production animal medicine, but decision analysis can also be applied on individual cases.
This book is very well written. It is easy to read, does not contain many complex formulas, but still succeeds to explain all essential statistical backgrounds necessary to understand how evidence-based veterinary medicine works. The way of thinking described in this handbook should be the basis for every day's veterinary medicine in practice and veterinary teaching. The book is highly recommended for reading. But above all, this book should be an integral part of teaching veterinary students. It may be hard to change the working methods and way of thinking of the long-settled veterinarians, but when students are made familiar with evidence-based veterinary medicine and apply it under all circumstances in their education, they will become better veterinarians. It will prepare them better to use the quickly expanding world of biomedical information. The skills of evidence-based veterinary medicine will help academic teachers to educate graduates who appreciate that lifelong, self-directed and problem-based learning is the key to high quality veterinary medicine in an ever-changing world.