Do you see an elephant or just its trunk?The need of learning Modern Epidemiologic Methods: An introduction

There is famous story wherein several blind men were asked what is the elephant is like. While one of them said it is like a pillar, another man said “snake” and each talked of it differently as they felt it. 1 In epidemiology, many of the hypotheses being evaluated in the interpretation of studies can be seen as auxiliary hypothesis in the sense that each blind person is feeling the elephant and describing individual experience. Particularly, each observation is independent of the presence, absence or direction of any causal connection between the study exposure and the disease. Much of the interpretation of epidemiological studies amounts to the testing of such auxiliary explanations for observed associations. 2