In a trial where the value of a biological response, such as change in lung function, is the primary endpoint, the data would often be continuous in nature, and thus comparison could be made via the means of the different arms or groups in the trial. However, another researcher may choose to analyse the time to the mortality event. When a mortality rate is the endpoint, data is often of a binary nature, and thus the data take the form of proportions. The primary outcome chosen will also decide the type of data that will be analysed at the end of the study. Guidance on the issue of estimands can illustrate how this issue can be more complex than expected. For example, where there are multiple endpoints to measure, or where we want to make a composite measure of the outcome to make conclusions about the study question. Often this is simple to define but in some cases it can be more complex. In an oncology trial, that might be the mortality rate in the treatment group and the control group or in an educational study it might be the measurement of grades or the attendance. This is the endpoint we will measure in order to make a conclusion about the study question. The next thing you’ll ask, having established your main study question(s), is what is the primary outcome (or primary outcomes) in the study. What is the primary outcome of the study? For example, in an oncology trial, we may want to see if the new treatment reduces mortality, or in a classroom intervention we may be interested in seeing if the intervention improves grades.Įstablishing the study question is vital as it has knock-on effects on all the other assumptions and choices discussed below that will be made when planning the study. It is vital at an early stage we establish “what do we want this study to tell us?”. The study questions inform what conclusions can be made at the end of the study. It must be established what the study question, or questions are.
0 Comments
Leave a Reply. |