- 20.1: Epidemiology
- Just because A is often associated with B, does not prove that A causes B. How can one establish that A causes B? In the laboratory you could set up a controlled experiment treating one group of animals with A and having a second control group without A but otherwise treated the same (thus avoiding confounding variables). Such experimentation is rarely possible (or ethical) in humans so we must turn to the methods and criteria of epidemiology.
- 20.2: Types of Clinical Studies
- Researchers in human (and veterinary) medicine are always on the lookout for new drugs, medical procedures, and life-style changes that will improve their ability to bring better health to patients. For each one, they must establish whether it truly represents an improvement from what was used before.
- 20.3: Scientific Methods
- There is nothing mysterious or even particularly unusual about the things that scientists do. There are many ways to work on scientific problems. They all require common sense. Beyond that, they all display certain features that are especially - but not uniquely - characteristic of science.
Thumbnail: Original map by John Snow showing the clusters of cholera cases in the London epidemic of 1854. (Public Domain).