Evidence-based psychiatry is a method of studying and treating disorders in mental health that is based in empirical knowledge and evidence rather than folk remedies and intuition. There are many different practices in all fields, including psychiatry, that are done primarily because "that's the way it has always been done" and not because they are necessarily helpful practices. Practitioners of evidence-based psychiatry seek to cut out these practices and use only those that are supported by empirical evidence. This also involves making sure that empirical data is widely available both to psychiatrists and to patients. Evidence-based and other types of psychiatry, and even other fields of medicine, are sometimes studied through meta-analysis by sociologists and philosophers of science.
An important aspect of evidence-based psychiatry that allows practitioners to assess the effectiveness of various techniques and to connect specific results to particular techniques is taking rigorous, detailed records. This involves detailing all techniques used, providing quantitative data regarding time and all medication used, and monitoring all changes in patient condition with great detail. This method is in opposition to methods of record keeping that are merely anecdotal and that lack any quantitative rigor. Any speculation or changes in practice in evidence-based psychiatry should be firmly based in quantitative observation, not drawn from speculations based on anecdotal or poorly-recorded evidence.
Even in evidence-based psychiatry, the judgment of the individual psychiatrist is very important, as similar symptoms may arise from very different disorders. Only through understanding the subtleties of the patient's condition can the practitioner make effective judgments about the best treatment options. Psychiatric practices that take all aspects of the individual patient into consideration, including sex, age, and background, fall into the category of "personalized medicine." Altering treatment methods based on the individual, even if it means treating two people differently for the same condition, does not mean abandoning evidence-based psychiatry. The psychiatrist must take a variety of factors into consideration before treating a patient — the important part is actually taking those factors into consideration and not acting purely on intuition.
Sociologists and philosophers of science often study the best methods of psychiatric practice through meta-analysis of a variety of different treatment styles. In general, one practitioner, whether he practices medicine in a highly traditional manner or based on rigorous adherence to evidence, will have some successes and some failures. As such, one cannot judge from just one practice whether or not evidence-based psychiatry or some other method is the most effective. Meta-analysis seeks to examine many different practices and, from the information gathered, to determine which method is more effective. Analysis of many different practices allows researchers to draw conclusions that would be impossible from analyzing just one.