A clinical trial is run to investigate the effectiveness of an experimental drugin reducing preterm delivery to a drug considered standard care and toplacebo. Pregnant women are enrolled and randomly assigned to receive eitherthe experimental drug, the standard drug or placebo. Women are followedthrough delivery and classified as delivering preterm (< 37 weeks) or not. Thedata are shown below. Is there a statistically significant difference in theproportions of women delivering preterm among the three treatment groups?Run the test at a 5% level of significance. Give each of the following1) the appropriate null and alternative hypotheses; 2)the appropriate test; 3) the decision rule; 4) the calculation of the teststatistic; and 5) your conclusion including a comparison to alpha or thecritical value.Preterm DeliveryTotalYesNoExperimental DrugStandard DrugPlaceboTotal33403245131817353783120

For the given data, the chi-square test for association is appropriate.Null Hypothesis:H0: There is…

Answered: A clinical trial is run to investigate…

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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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…
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Rogers, Farlow, and colleagues (1998) conducted an experiment to investigate whether donepezil improved cognitive function in patients with mild to moderate Alzheimer’s disease (AD). A total of 1,775 patients were randomly assigned to treatment with either donepezil or a placebo (a look-alike pill with no pharmacological effect). Cognitive function, as measured by the Alzheimer’s Disease Assessment Scale (ADAS-cog), was significantly improved in patients taking donepezil compared with the placebo group at weeks 12, 18, and 24. [Source: Rogers, S. L., Farlow, M. R., Doody, R. S., et al. (1998). A 24-week, double-blind, placebo controlled trial of donepezil in patients with Alzheimer’s disease. Neurology, 50, 136–145.] In this experiment, the independent variable is , and the dependent variable is . The individuals who are in the control condition are typically referred to as the control group. Here, the control group consists of . is a construct that is being tested in this…
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