I was wondering - what's the relationship between chi square and odds ratio? To me it makes sense that these two values are fixed- i.e., if one value changes, the other will. Is it possible to observe the same odds ratio in two different tests with different sample sizes but get a different chi square value? I can't imagine it would, because getting more samples will result in different values being used in the cells for the calculation of the OR...

Many thanks if anyone can help