Question

In: Math

1.A researcher is investigating the effect of a new drug to lower anxiety. The drug was...

1.A researcher is investigating the effect of a new drug to lower anxiety. The drug was shown to be safe in humans, and the researcher wants to test what dosage of the drug is needed. He assigned twenty participants with clinical anxiety disorder to four treatment groups, then gave each the treatment regimen for four weeks. At the end of the trial, the participants took an anxiety test. The scores, corrected for initial anxiety score, are reported in the table below. Lower scores indicate lower anxiety levels. Analyze the data to determine if there is any difference in anxiety scores between the groups, and if there is a difference, determine and explain which treatment is most effective

CONTROL PLACEBO LOW DOSE MODERATE DOSE
35 36 17 16
40 28 13 10
38 34 27 3
28 22 21 12
33 25 29 6
  1. What kind of statistical test will you be performing?
  2. Will you need to test for equal variance? If so, what are your results and how does that influence the next steps in your analysis?
  3. What are your null and alternative hypotheses?
  4. Discuss the results of your analysis. Will you accept or reject your null hypothesis? Why? What can you specifically say about the data?

Solutions

Expert Solution

We can see the mean anxiety score of Moderate dose treatment is less as compared to other treatments. Hence the treatment Moderate dose is most effective.


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