Planning and practice of clinical research: Basic principles and errors as exemplified by Russian diabetology (A lecture)

In one of the previous publications, the main indicators of the quality of diabetes care in our country have already been analyzed. One of the main (if not the main) reasons for its unsatisfactory quality, in our opinion, is inconsistency of theory and practice with the modern world scientific and clinical level of diabetology. A number of provisions of domestic diabetology are still based on the approaches of the 50-70s. For some recommendations, it is generally impossible to find scientific justifications in either foreign or domestic literature. They are transmitted orally from endocrinologists of the older generation to the young, like legends, without being scientifically proven. The only justification for them is the statement this is our school or this is how practice shows. Any approaches are really tested by practice. That is why unsatisfactory indicators of compensation and acute complications and disability for diabetes mellitus indicate significant shortcomings in domestic diabetology. When an endocrinologist says that he repeatedly had to note, for example, the appearance of acetonuria in patients with insulin-dependent diabetes mellitus after a fatty meal, or the ophthalmologist discovers a positive dynamics of the state of the retina while taking angioprotectors, these facts in themselves, observations, even numerous ones, do not prove the existence of a causal relationship between the two phenomena. Even the ancients said: "After this - does not mean therefore." Due to the selectivity of attention and memory, the opposite cases, which are no less (in our example, the absence of acetonuria after a fatty meal or the preservation of hemorrhages, despite the many months of taking angioprotectors), prefer to not notice. That is why it seems appropriate to discuss strictly defined principles and rules of evidence-based scientific and clinical research existing in the world practice. The main objective of this article is to help scientists avoid methodological errors in research, learn how to plan them correctly, and practical doctors to critically and thoughtfully understand the publications of medical journals. Programs of medical faculties of many countries include special courses on the formation of a critical type of medical thinking and the ability to reasoned analysis (the course medical logic, decision analysis, critical analysis of the postulates of medicine, etc.), which also address research planning problems. For clarity, this publication will focus on clinical trials conducted with the participation of patients and with the goal, as a rule, of studying the effectiveness of a treatment method or an individual drug, the characteristics of the course of the disease under certain conditions, etc.