A local research firm often uses newspaper advertisements to invite individuals to volunteer for various experiments the firm is planning to conduct.One such study was to determine if a newly formulated cream had any beneficial effect on individuals suffering with psoriasis.Psoriasis sufferers were invited to participate in a study with volunteers to be given either the new cream or a placebo in the form of a cream with the similar appearance and feel as the new cream.What conclusions can be drawn from such studies involving volunteers?
A)Because there is bias associated with the selection of subjects,nothing can be concluded.
B)In such a study there is great potential for the presence of confounding or lurking variables,so little information can be gained.
C)If one believes the subjects form a representative sample from the population,useful information will be gained from such studies.
D)Because there is no control over the selection of subjects,little will be learned from such studies.
E)Useful information will be gained from studies such as this provided that the individuals who volunteer are randomly assigned to either receive the experimental treatment or the placebo.

Question

Quizplus · Accepted Answer

While there is potential for bias in subject selection, if the individuals who volunteer are randomly assigned to either receive the experimental treatment or the placebo, useful information can be gained from such a study. This helps to control for potential lurking or confounding variables and increases the likelihood that any observed differences between the two groups are due to the treatment being tested. However, it should be noted that the generalizability of the study results may be limited to the population from which the sample was drawn.

A Local Research Firm Often Uses Newspaper Advertisements to Invite