Treatment for HIV-1 In a 2018 study reported in The Lancet, Molina et al. reported on a study for treatment of patients with HIV-1. The study was a randomized, controlled, double-blind study that compared the effectiveness of ritonavir-boosted darunavir (rbd), the drug currently used to treat HIV-1, with dorovirine, a newly developed drug. Of the 382 subjects taking ritonavir-boosted darunavir, 306 achieved a positive result. Of the 382 subjects taking dorovirine, 321 achieved a positive outcome. See page 430 for guidance.
a. Find the sample percentage of subjects who achieved a positive outcome in each group.
b. Perform a hypothesis test to test whether the proportion of patients who achieve a positive outcome with the current treatment (ritonavir-boosted darunavir) is different from the proportion of patients who achieve a positive outcome with the new treatment (dorovirine). Use a significance level of
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- A 2017 article in The New England Journal of Medicine details the results of a randomized clinical trial designed to evaluate the efficacy of a rotavirus gastroenteritis vaccine designed for infants. As per the authors: “Each year, rotavirus gastroenteritis is responsible for about 37% of deaths from diarrhea among children younger than 5 years of age worldwide, with a disproportionate effect in sub-Saharan Africa. We conducted a randomized, placebo-controlled trial in Niger to evaluate the efficacy of a live, oral bovine rotavirus pentavalent vaccine (BRV-PV, Serum Institute of India) to prevent severe rotavirus gastroenteritis. Healthy infants received three doses of the vaccine or placebo at 6, 10, and 14 weeks of age. Episodes of rotavirus gastroenteritis were assessed through active and passive surveillance.” The following Kaplan-Meier curves show the time to a diagnosis of rotavirus gastroenteritis separately for the vaccine and placebo samples. Infants were followed for up to 60…arrow_forwardAn investigator reviewed the medical records of 200 children seen for care at Boston Medical Center in the past year who were between the ages 8-12 and identified 40 with asthma. He also identified 40 children of the same ages who were free of asthma. Each child and their family were interviewed to assess whether there might be an association between certain environmental factors such as exposure to second hand smoke. This study is an example of a: randomized controlled trial case-control study cohort study crossover trialarrow_forwardAn investigator reviewed the medical records of 200 children seen for care at Boston Medical Center in the past year who were between the ages 8 and 12 and identified 40 children with asthma. He also identified 40 children of the same ages who were free of asthma. Each child and their family were interviewed to assess whether there might be an association between certain environmental factors such as exposure to second-hand smoke. This study is an example of a: Case-Control Study Crossover Trial Cohort Study Randomized Control Trialarrow_forward
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- Hepatitis B and Pancreatic Cancer. The article “Study Links Hepatitis B and Cancer of Pancreas” by D. Grady, appeared in the September 29, 2008 issue of the NewYork Times. It reported that, for the first time, a study showed that people with pancreatic cancer are more likely than those without the disease to have been infected with the hepatitis B virus. The study by M. Hassan et al., titled “Association Between Hepatitis B Virus and Pancreatic Cancer” (Journal of Clinical Oncology, Vol. 26, No. 28, pp. 4557–4562) compared 476 people who had pancreatic cancer with 879 healthy control subjects. All were tested to see whether they had ever been infected with the viruses that cause hepatitis B or hepatitis C. The results were that no connection was found to hepatitis C, but the cancer patients were twice as likely as the healthy subjects to have had hepatitis B. The researchers noted, however, that “. . . while the study showed an association, it did not prove cause and effect. More work…arrow_forwardIn randomized, double-blind clinical trials of a new vaccine, infants were randomly divided into two groups. Subjects in group 1 received the new vaccine while subjects in group 2 received a control vaccine. After the second dose, 129 of 674 subjects in the experimental group (group 1) experienced drowsiness as a side effect. After the second dose, 86 of 555 of the subjects in the control group (group 2) experienced drowsiness as a side effect. Does the evidence suggest that a higher proportion of subjects in group 1 experienced drowsiness as a side effect than subjects in group 2 at the a = 0.10 level of significance? Verify the model requirements. Select all that apply. O A. The samples are independent. O B. The sample size is more than 5% of the population size for each sample. O c. The data come from a population that is normally distributed. O D. The samples are dependent. O E. The sample size is less than 5% of the population size for each sample. OF. n,Pi (1-ê) 2 10 and nz2…arrow_forwardIn randomized, double-blind clinical trials of a new vaccine, infants were randomly divided into two groups. Subjects in group 1 received the new vaccine while subjects in group 2 received a control vaccine. After the second dose, 129 of 674 subjects in the experimental group (group 1) experienced drowsiness as a side effect. After the second dose, 86 of 555 of the subjects in the control group (group 2) experienced drowsiness as a side effect. Does the evidence suggest that a higher proportion of subjects in group 1 experienced drowsiness as a side effect than subjects in group 2 at the a = 0.10 level of significance? Verify the model requirements. Select all that apply. YA. The samples are independent. O B. The sample size is more than 5% of the population size for each sample. O c. The data come from a population that is normally distributed. O D. The samples are dependent. YE. The sample size is less than 5% of the population size for each sample. nội (1-P1) 2 10 and nz2 (1- P2) 2…arrow_forward