When we have to adopt intervention design rather than descriptive? is there any need to conduct descriptive studies these days? and, how much are the chances to find journal to publish descriptive sutdy?
Descriptive studies are still essential in areas which we know little about. However, in my opinion, it is about time we stopped describing the situation in many areas, and started intervening. For example, I do not think we need any more studies to demonstrate that poorer people have poorer health. If journals are becoming reluctant to publish the results of descriptive studies, in many instances, it is probably a good thing.
It depends on the specific area that the researcher wants to find answers about. In relatively unexplored areas of research, sometimes descriptive analyses can be useful. Also, often a descriptive analysis can be useful as a first step before someone undergoes an inferential analysis.