All research is done within the framework of a discipline. First, a discipline defines what sort of questions can be asked. For example, if you are looking at an organic chemical in medical research, your questions would be ones about its effect on health rather than whether it dyes fabric a nice colour or can be used in cooking. Next, previous studies tell you what is already known. Thus your task becomes either replicating a previous study or thinking about how to frame your questions to obtain new information. For example, if several studies have proven a drug safe and effective for adult men, it might be better to study its effect on women or children.