Below you will find some examples of study designs, please select the correct design for each example. The relation between total fiber intake and colon cancer was studied in 35492 male participants. Fiber intake was measured via food frequency questionnaires at the beginning of the study in 1988 and every two years thereafter prior to an endoscopic procedure to assess colon cancer. Between 1988 and 2006, 2099 colon cancer cases occurred. Occurrence of colon cancer was 39% higher in people with the lowest fiber intake as compared with people with the highest fiber intake. The study suggests that low intakes of fiber in men is associated with an increased risk of colon cancer. The study design is a:
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- We evaluated the associations between serum omega-3 and omega-6 poly-unsaturated fatty acid levels and colon cancer risk in a study conducted between 1997 and 2002. We included 363 cases of colon cancer and 498 disease-free controls. Serum omega-3 poly-unsaturated fatty acid levels were inversely associated with colon cancer risk. Subjects in the upper 33% of serum omega-3 poly-unsaturated fatty acids had a 33% lower risk of colon cancer as compared with subjects in the lower 33% of serum omega-3 poly-unsaturated fatty acids. In contrast, the risk of colon cancer was increased by omega-6 poly-unsaturated fatty acids by 68%. This is the first study that simultaneously finds an inverse association of serum omega-3 poly-unsaturated fatty acids and a positive association of omega-6 poly-unsaturated fatty acids with colon cancer. The study design is a:
- In the present study, we examined expression of PGE2 subtypes EP1, EP2, EP3, and EP4 in normal colon mucosa and colon cancers, and assessed the _____ of EP3 to colon cancer.
- Dietary intervention might reduce risk to colon cancer, which is not included A: Reduce the amount of fat and red meat in your diet B: Increase your intake of fruits and vegetables C: Take natural vitamins D: Keep on alcohol consumption
- A. None of the evidence on dietary protein and specific health outcomes can be classified as “conclusive”</p></p><p><p>B. The relation between protein intake and cancer mortality and cancer diseases can be classified as “probable”</p></p>
- The striking example in The Journal of the American Medical Association aims to prove ________. A: the five years following surgery is dangerous in that there is much likelihood to have recurrence. B: surgical removal is not reliable because it could not eliminate all cancer cells of colon cancer. C: The Journal of the American Medical Association often reports the latest discovery in science. D: Western diet, in some uncertain way, excites the growth of cancer cells after the surgery.