Two separate investigators have conducted cohort studies to calculate the risk of lymphoma in rheumatoid arthritis patients taking anti-TNF alpha medications. They each followed patients with rheumatoid arthritis for a number of years and tracked the number of patients who were diagnosed with lymphoma. The results of the two studies are summarized in the table. Number of patients Follow-up period Number of new cases of lymphoma Study 1 3000 10 years 30 Study 2 300 30 years 9 Based on these results, which of the following statements about the risk of lymphoma is most accurate?
AThe risk is higher in study 1, with an incidence rate of 30 cases per 10 person-years
BThe risks are equivalent, with a prevalence of 39 cases per 3300 persons
CThe risks are equivalent, with an incidence rate of 1 case per 1000 person-years
DThe risk is higher in study 1, with a prevalence of 30 cases per 3000 patients
EThe risk is higher in study 2, with a cumulative incidence of 9 cases per 300 patients
A 25-year-old man with a genetic disorder presents for genetic counseling because he is concerned about the risk that any children he has will have the same disease as himself. Specifically, since childhood he has had difficulty breathing requiring bronchodilators, inhaled corticosteroids, and chest physiotherapy. He has also had diarrhea and malabsorption requiring enzyme replacement therapy. If his wife comes from a population where 1 in 10,000 people are affected by this same disorder, which of the following best represents the likelihood a child would be affected as well?
A0.01%
B2%
C0.5%
D1%
E50%
A researcher is designing an experiment to examine the toxicity of a new chemotherapeutic agent in mice. She splits the mice into 2 groups, one of which she exposes to daily injections of the drug for 1 week. The other group is not exposed to any intervention. Both groups are otherwise raised in the same conditions with the same diet. One month later, she sacrifices the mice to check for dilated cardiomyopathy. In total, 52 mice were exposed to the drug, and 50 were not exposed. Out of the exposed group, 13 were found to have dilated cardiomyopathy on necropsy. In the unexposed group, 1 mouse was found to have dilated cardiomyopathy. Which of the following is the relative risk of developing cardiomyopathy with this drug?
A12.5
B25.0
C13.7
D16.3
E23.0
+ 7 more in the PDF
Browse all chapters