Basic principles of conducting clinical studies for the evaluation of disease outcomes. Advice for clinicians

This article describes the main methodological approaches to conducting studies related to the evaluation of disease outcomes, including patient survival. It explains the key concepts used in survival analysis. The main stages of planning and conducting a study are considered, as well as the sources of common errors that arise during this process. The article presents the main characteristics of statistical methods used in the analysis of disease outcomes and their clinical interpretation. The primary methods of prognosis based on survival analysis results are reviewed. The role of various types of clinical studies in the evaluation of disease outcomes is discussed. Typical errors occurring in the interpretation of studies assessing disease outcomes are analyzed.