confounding factors
Last reviewed 01/2018
Confounding factors may be described as the association of a disease and a study factor with a third variable causing a spurious difference between cases and controls.
Consider:-
A (confounder) <-------------------> C (dependent)<-------------------> B (independent)
Thus the association of A and B is secondary, resulting from them both being related to the confounding variable.
To overcome confounding, matching is carried out.