Читать книгу Evidence in Medicine - Iain K. Crombie - Страница 23

The effectiveness of a treatment is assessed by comparing the health status of those in the intervention and control groups at the end of the trial. In many clinical settings the effect of treatment could be measured by several different outcomes. For example, in cancer trials possible outcomes would include the average survival time, disease‐free survival or quality of life. Commonly, one outcome measure is designated the primary outcome, with the other outcomes being termed secondary measures. (This is to prevent researchers from analysing many different outcomes, then highlighting the one which looks best.) Selecting the primary outcome involves difficult choices, but it greatly simplifies the interpretation of the results.