Final answer:
The baseline in an experimental study provides a comparison for progress to evaluate the effectiveness of a treatment approach.
Step-by-step explanation:
The baseline in an experimental study serves as a comparison for progress in order to evaluate the effectiveness of a treatment approach. When comparing an experimental group to a control group, the baseline helps researchers determine if there are any meaningful changes resulting from the treatment. For example, in drug trials, the baseline indicates the state of health before the intervention, and subsequent measurements are compared to this initial data point to assess the drug's efficacy. Proper experimental design, incorporating control groups who may receive a placebo treatment, ensures that any observed differences in outcomes are likely due to the treatment and not other factors. Ethical considerations prevent harmful or deceptive practices, and statistical significance is sought to ensure that the results of the study are not simply due to chance.