National Counselor Exam (NCE)

What characterizes a confounded study?

1. It uses a control group for comparison

2. It has clear independent and dependent variables

3. It contains undesirable variables that can affect the results

4. It relies exclusively on observational data

The correct answer is: It contains undesirable variables that can affect the results

A confounded study is characterized by the presence of undesirable variables that can impact the results, leading to ambiguity in interpreting the relationship between the independent and dependent variables. When confounding variables are present, they can obscure the true effect of the independent variable by introducing alternative explanations for observed outcomes. This makes it difficult to ascertain whether the changes in the dependent variable are genuinely due to the independent variable or influenced by these extraneous factors. Clear definitions of independent and dependent variables or the presence of a control group can contribute to a well-designed study, but these characteristics alone do not suffice to eliminate the issues posed by confounding variables. Reliance on observational data, while valuable, also does not inherently lead to confounding; it is the failure to control for additional variables that primarily causes the confounding effect. Therefore, the accurate representation of a confounded study is that it contains these undesirable variables that can distort the results.