One hundred sixty people who suffer from painful diabetic neuropathy have volunteered to participate in a study. Eighty are selected at random and are given the drug gabapentin, which (although originally intended to prevent epileptic seizures) has properties that may make it useful to alleviate neuropathy. The remaining participants are given a placebo. A neurologist evaluates the symptoms of all volunteers after two months to determine if there has been substantial improvement in the severity of the symptoms. Does the use of volunteers make this study invalid?
A)Yes, because of volunteer bias.
B)Yes, because there is no way to determine the effect of the drug on people that do not have symptoms of neuropathy.
C)No, because the subjects are randomly assigned to treatment groups.
D)No, because blocking was used.

Question

Quizplus · Accepted Answer

Random assignment to treatment groups helps to reduce bias and make the study valid, even when using volunteers. The use of a placebo group also helps establish the effectiveness of the drug being tested. Option B is not relevant to the question as it asks about the validity of the study dealing with the effects of gabapentin on painful diabetic neuropathy. Option D is not mentioned in the question, so it cannot be determined if blocking was used or not. Option A is incorrect because although volunteer bias is a potential issue, it can be addressed by randomly assigning participants to treatment groups.

One Hundred Sixty People Who Suffer from Painful Diabetic Neuropathy