The quote is taken from a scientific paper published in the New England Journal of Medicine, and is referenced from quite a large number of web sites, so I assume it is seen as an important paper. Bear with me here as I am trying to explain something. Would it be fair to suggest that a layman might take it to mean that the real relative risk must have a 95% chance of falling inside the interval, or that the speaker is 95% sure that the two things are linked, or that the claim that exposure to environmental smoke causes coronary heart disease is 95% likely to be right, or some such? 125.255.16.233