What can be potentially compromised if controls are not used in an experiment?

The validity of the results is a crucial aspect of any experiment, and if controls are not implemented, it can lead to numerous issues. Controls are essential for establishing a baseline or reference point against which the experimental outcomes can be measured. Without these controls, it's challenging to determine whether the observed effects in the experiment are due to the independent variable being tested or if they result from other external factors, known as confounding variables.

For instance, if you're testing a new drug, controls such as a placebo group are necessary to ensure that any observed effects on the participants can be attributed specifically to the drug rather than psychological factors or natural variation over time. If the results are compromised due to a lack of controls, they may not be generalizable or reproducible, thereby undermining the integrity of the findings.

While timing of the experiment, resources required, and participants' understanding are important factors, they do not directly impact the legitimacy of the data collected. The primary concern with omitting controls relates directly to the accuracy and reliability of the conclusions drawn from the experiment.