Concept explainers
Effectiveness of a New Drug. As part of the U.S. Food and Drug Administration’s approval process, a new rheumatoid arthritis drug was compared to a placebo. The randomized, double-blind study with 482 patients showed that 41% of those given the new drug had a decrease in symptoms, while 19% of those given the placebo experienced improvement (Western Journal of Medicine).
a. Which patients were in the treatment group and the control group?
b. Do the results appear to offer evidence that the new drug was effective? Why or why not?
c. Do the results appear to indicate that a placebo effect was present in these trials? Explain.
d. If you were on the panel deciding whether to approve the new drug, how would you vote based on this study? Explain your reasoning.
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- What is an experiment?arrow_forwardWhat is meant by the sample space of an experiment?arrow_forwardThe District of Columbia Opportunity Scholarship Program was created by Congress to provide tuition vouchers to low-income parents who want their child to attend a private school. In 2012–2014, a treatment group of 995 students were randomly selected to receive a tuition voucher, while a control group of 776 students did not receive vouchers. One year later, the students were given a standardized reading test. The average score of the students in the treatment group was 601.78 with a standard deviation of 52.65; the average score of the control group was 605.78 with a standard deviation of 55.73. At the level of significance alpha = 0.01, do we have enough evidence to conclude that the average reading score of students who receive a tuition voucher to attend private school is lower than the average reading score of students who do not receive a tuition voucher?arrow_forward
- What is the distinguishing feature of a case-control study such as this? An epidemiologist performed a case-control study examining whether tobacco use was associated with oral cancer. The investigator recruited a random sample of 75 adults with oral cancer and 72 adults without oral cancer. Participants were interviewed and asked about their history of tobacco use. O Exposure status was assessed, and then the participants were followed up over time to see who developed the outcome. O The exposure and outcome were measured at the same time, so temporality cannot be established. O Participants were selected based on disease status, and then exposure status was assessed from the past. O The investigator randomized participants into exposure groups and then followed them to see who developed the outcome.arrow_forwardWhirling disease is a deadly disease that affects trout in Montana riversIn a follow-up to a 2006 study conducted by the Montana Department of FishWildlife and Parks (FWP)researchers sought to determine if the proportion of trout afflicted by whirling disease in the Gallatin river differs between rainbow trout and brown trout. To test this theory, researchers collected a representative sample of 527 rainbow trout and 459 brown trout. Of the 527 rainbow trout collected, 120 had developed whirling disease; of the 459 brown trout collected, 74 had developed whirling disease Calculate the relative risk of whirling disease for rainbow trout compared to brown trout in this sample.arrow_forwardPrenatal vitamins and Autism. Researchers studying the link between prenatal vitamin use and autism surveyed the mothers of a random sample of children aged 24 - 60 months with autism and conducted another separate random sample for children with typical development. The table below shows the number of mothers in each group who did and did not use prenatal vitamins during the three months before pregnancy.arrow_forward
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