State how the control will be treated differently from the experimental group. What 2 factors might be studied in both group?
The drug usually used to treat high blood pressure do not affect blood vessels in the lungs. Bosentan is a new drug being studied as treatment for high blood pressure in the lungs. In an experiment, patients treated with bosentan showed an improvement in the distance they could walk without fatigue within 12 weeks.
In a well designed experiment it is important that the experimental group be controlled in such a way as to insure that a single variable be modified and that the resulting changes due to those modifications can be observed accurately. The variable which the researcher wishes to alter is the "independent variable" and the one which is changed do to those modifications is the "dependent variable."
To make sure that the only thing which is causing changes in the dependent variable is changes in the independent variable, it is important to have a control group. The control group is identical to the experimental group in every way with the exception that the independent variable will not be modified. This allows the researcher to compare any changes in the experimental group to the control group to verify that the changes were caused by the experiment and not by other factors.
In the sited experiment it is apparent that the researcher is studying the effects of the drug on lung function by monitoring reductions in stress from walking. The control group should be as close to the experimental group as possible in every way including health conditions and distance walked with the exception of using the drug. The experimental group would be given a regular repeated dosage and the control would not be given the drug.
One of the two factors which could be studied in both groups would be the patient's blood pressure as it could be reduced by either the drug, the walking, or a combination of both. The second factor would be the ease of walking as walking could get easier due to increased fitness because of walking every day, the drug, or a combination of the both.