A study examined the effect of garlic on blood cholesterol levels. A total of 192 subjects with starting low-density lipoprotein (LDL) cholesterol ("bad cholesterol") levels between 130 and 190 mg/dl were randomly assigned to one of four treatments for six months: raw garlic eaten daily, a powdered garlic supplement taken daily (Garlicin brand), an aged-garlic extract taken daily (Kyolic brand), or a placebo pill taken daily. The study found no significant or clinical differences in blood cholesterol levels between the four groups at the end of the study.
What are the explanatory and response variables, respectively?

Question

Quizplus · Accepted Answer

The explanatory variable is the treatment type (raw garlic, powdered garlic supplement, aged-garlic extract, or placebo), and the response variable is the cholesterol level, which the study aimed to measure the effect on.

A Study Examined the Effect of Garlic on Blood Cholesterol