Epidemiological research studies address questions like, “If 1,000 people with type 2 diabetes were randomly allocated to four groups of 250 people that each received either no treatment (or a placebo), drug A, drug B, or drug C for ten years, how would it impact survival rates, and what, if any, complications and side effects would there be?” If the trial is conducted properly – it is large enough; people are allocated in a truly random way; and “blind” assessments of the outcomes are conducted – the results should be reliable.