The phrase "to detect an effect" means to identify or notice the result or consequence of something happening or being done. It refers to recognizing the impact that an action, event, or condition has had on a situation. Full definition
However, she notes, her team's tests only could detect an effect on bee growth if it had been large. (sciencenewsforstudents.org)
Thus, we developed longer versions for smaller studies in which this might serve as a primary outcome measure - providing the highest precision and power for detecting effects. (couples-research.com)
It's also an appropriate design for studies with small sample sizes that may not have the desired power for the statistical analysis to detect an effect when there is one. (tribaleval.org)