The relative risk of 1 indicates that: (A) There is no cause effect relationship, (B) Effect may be due to type 1 error, (C) Strong correlation, (D) Effect may be due to type 2 error
Answer is A. Relative risk is the ratio of the incidence of the disease (or death) among exposed and the incidence among non-exposed. A relative risk of 1 means the incidence in exposed and non-exposed is same. So there is no relation between disease and cause (exposure). Park, pg: 79