A recent case control study exploring the relationship between high physical activity (PA) and breast cancer reports a crude OR of 0.51. When stratified for menopausal status, the OR for pre-menopausal women is 0.46 and the OR for post-menopausal women is 0.9?Is effect modification present?

Group of answer choices

Yes, the stratum specific ORs are different from the crude and each other.

No, the crude OR is different from the stratum specific OR, but stratum specific are not different from each other.

Yes, the stratum specific ORs are all the same.

No, the stratum specific ORs are different from the crude and each other.