These initial ideas are unlikely to be based on any preconceived ideas about what is going on. Formulate Hypotheses and Make Predictions. Once we have gained some idea about the system we are interested in, we should attempt to make our ideas about that system more explicit and generate hypotheses. Science is often not viewed as a creative process, yet scientists who are unable to formulate a range of feasible hypotheses will make little progress. Design an Appropriate Experiment.
Experimental design is crucial.
At the end of the experiment, we would look for differences between the levels of disease in the two groups. It is this difference which we could then attribute to the drug. Where possible, steps must be taken to overcome this bias, e.g. blind tests. It is usually necessary to ensure that data points are independent from each other. Thus, lots of measurements taken from a single subject would not be independent of each other.