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. This study would be double-blind if:
A)neither drug had any identifying marks on it.
B)neither the volunteers nor the neurologist were allowed to see each other during the session in which the neurologist evaluated the severity of the symptoms.
C)neither the volunteers nor the neurologist knew which subjects had received the drug and which had received the placebo.
D)All of the answer options are correct.

Question

Quizplus · Accepted Answer

A study would be double-blind if neither the volunteers nor the neurologist knew which subjects had received the drug and which had received the placebo. Option A is not relevant as the presence of identifying marks does not affect blinding. Option B is not correct as physical separation does not necessarily guarantee blinding. Option D includes all options, but not all of them are correct (option A and B are not correct).

One Hundred Sixty People Who Suffer from Painful Diabetic Neuropathy