Question

1. A case-control study of the relationship between high-fat diet and diabetes was performed. The results of the study are shown below, stratified by gender.

	Men High Fat Diet	Men Low Fat Diet	Women High Fat Diet	Women Low Fat Diet
Diabetes	1410	1600	980	558
No Diabetes	2080	1120	1160	900

1. Calculate and interpret the crude odds ratio for the association between high-fat diet and diabetes in this study?
2. Calculate and interpret the odds ratio among men for the association between high-fat diet and diabetes in this study?
3. Calculate and interpret the odds ratio among women for the association between high-fat diet and diabetes in this study?
4. Based on your findings, which measure of association should you report? Explain your response.
5. 1. The odds ratio among women only
   2. The separate stratum-specific odds ratios
   3. The odds ratio after adjustment for gender
   4. The crude odds ratio

Answer 1

	Men High Fat Diet	Men Low Fat Diet	Women High Fat Diet	Women Low Fat Diet
Diabetes	1410	1600	980	558
No Diabetes	2080	1120	1160	900

a)

high fat and diabetes

Total fat and total diabetes

odd ratio = (1410+980) * (1120+900) / (2080+1160) *(1600+558)

=0.6904

< 1

so, high fat diet is riskier

b)

for men

odd ratio = 1410*1120    / (2080*1600)

= 0.4745

< 1

c)

for women

odd ratio =(980*900) /(558*1160)

=1.3626

>1

for women high fat diet is relevent as compared to low fat diet

d)

in case of women,

odd ratio is greater than 1, it implies that high fat diet has more non diabetic

so it prevalance to low fat diet . so should be reported