8. We are now examining the relationship between smoking and stroke. We suspect that the relationship between smoking and stroke may be different in older women (>70) compared to younger women (<=70). Examining the table below calculate the Mantel-Haenszel estimate of the RR. Next perform the test for a common relative risk across all strata. What do you conclude from this test? Lastly provide the log of the risk of stroke for smokers and non-smokers in younger and older women. Looking at these four risks what type of interaction is present?

	Younger women (<=70)	Older women (>70)
smoking	Stroke	Controls	Total	Stroke	Controls	Total
Yes	70	2065	2135	7	48	55
No	50	3459	3509	9	37	46
Total	120	5524	5644	16	85	101