Smoking during pregnancy is often mentioned as a cause of bi…
Smoking during pregnancy is often mentioned as a cause of birth defects, such as cleft lip. However, not all babies born to mothers who smoked during pregnancy develop cleft lip. Use the sufficient cause framework to explain why not all babies born to mothers who smoked during pregnancy develop cleft lip. Make sure to include the terms component cause and sufficient cause in your answer (max. 6 points).
Read DetailsSuppose a team of researchers investigated the association b…
Suppose a team of researchers investigated the association between obesity and gallstones using a prospective cohort study design. The researchers were concerned about confounding by high cholesterol diet, so they performed a few different analyses in which they attempted to minimize confounding. The results of their analyses are reported in Table 1. Table 1. Unadjusted, stratified, and Mantel-Haenszel effect estimates from the hypothetical study on obesity and gallstones. Unadjusted Estimates Estimates for the subsample with a low cholesterol diet Estimates for the subsample with a high cholesterol diet Mantel-Haenszel estimates Odds ratio 3.24 3.01 2.83 2.92 Risk difference 0.20 0.17 0.17 0.17 Based on the information in Table 1 report the following information: Was it appropriate to estimate an odds ratio using Mantel-Haenszel methods (yes/no)? (2 points) Explain why this is/is not appropriate (2 points). Was it appropriate to estimate a risk difference using Mantel-Haenszel methods (yes/no)? (2 points) Explain why this is/is not appropriate (2 points).
Read DetailsA team of researchers conducted a prospective cohort study t…
A team of researchers conducted a prospective cohort study to determine if children who were exposed to secondhand smoke at home are more likely to develop asthma compared to children who were not exposed to secondhand smoke at home. The researchers computed a risk ratio of 1.52 with a standard error of 0.17. As the next step, the researchers want to estimate a 95% confidence interval for the risk ratio using the following formula: ??? ± 1.96 * 0.17. What value should the researchers use in place of ??? in the formula?
Read DetailsA team of researchers conducted a prospective cohort study t…
A team of researchers conducted a prospective cohort study to determine if children who are born to mothers who took folic acid during pregnancy are less likely to develop leukemia. The average age at which childhood leukemia is diagnosed is about 2 years old. To ensure that leukemia is detectable in the children included in the study, the researchers decided to follow mothers and their children from pregnancy until the age of 3. What period did the researchers consider when determining the length of follow-up?
Read Details