The result established from a control condition when no manipulation of the IV occurs is called what?

• A. Baseline measure
• B. Reactivity effects
• C. Non-equivalent groups
• D. Placebo group

Answer: (A)

Baseline measurement is the starting value recorded before any manipulation of the independent variable. It serves as the reference point against which any effect of the intervention is judged. In a control condition where nothing is changed, the observed outcome reflects this pre-manipulation state—the baseline. By comparing later measurements to this baseline, you can determine whether the independent variable produced a change. For example, measuring attention before any sleep manipulation lets you see how performance differs after the manipulation. The other terms describe different ideas: reactivity effects are changes caused by the act of being measured, non-equivalent groups refer to a design flaw with incomparable groups, and a placebo group is a control that receives an inert treatment rather than simply no manipulation.