In a clinical trial, 780 participants suffering from high blood pressure were ra
ID: 3072650 • Letter: I
Question
In a clinical trial, 780 participants suffering from high blood pressure were randomly assigned to one of three groups. Over a one-month period, the first group received a low dosage of an experimental drug, the second group received a high dosage of the drug, and the third group received a placebo. The diastolic blood pressure of each participant was measured at the beginning and at the end of the period and the change in blood pressure was recorded. Identify the experimental units a.(2 points) What are the units? b. 3 points) List all the variables. c. (2 points) Which variables are quantitative? Which ones are qualitative (categorical)? d. (3 points) Does the study employ random sampling or random assignment? (circle one) random sampling random assignment e. (2 points) Is this an observational study or an experiment? f (3 points) Can the results of the study be generalized to the population at large?Explanation / Answer
Solution: a. What are the units?
Answer: 780 participants in the experiment are the units.
b. List all the variables.
Answer: The variables in the study are:
c. Which variables are quantitative? Which ones are qualitative?
Answer: Diastolic blood pressure and change in blood pressure are quantitative variables. The dose of drug is qualitative (categorical) variable.
d. Does the study employ random sampling or random assignment?
Answer: Random assignment
e. Is this an observational study or an experiment?
Answer: Experimental study
f. Can the results of the study be generalized to the population at large?
Answer: No, the results of the study can not be generalized to the population at large because the experimental units of the study have high blood pressure and we can not use their results for the people who have either normal blood pressure or low blood pressure.