Why Should We Make Multiple Trials of an Experiment?

How Multiple Trials Are Conducted

• There are several ways that multiple trials can be conducted. One method is to repeat the same exact experiment several times. All conditions would be replicated with the expectation of achieving very similar results. Another way to conduct multiple trials is to vary one condition in every experiment. Doing so helps researchers understand what effect that specific variable has on the outcome of the experiment.

Testing for Reproducibility

• When conducting multiple trials, scientists are testing for the reproducibility of the experiment, or how well the same results can be achieved every time. The results of an experiment that can be produced by different researchers in other laboratories are more likely to be trusted and validated by the scientific community. For this reason, when documenting the experiment it is important to be as detailed and accurate as possible in explaining the methods and materials used.

If the Results Are Not Reproducible

• If multiple trials have been conducted and the results have shown to include a significant amount of variability, it likely points to a mistake being made by the researchers or to some element of the experiment that has not been controlled. Researchers will have to pinpoint the reason for the different results and conduct further trials to confirm their suspicion. Sometimes important discoveries have been made when searching for the reasons of a lack of reproducibility.

After the Multiple Trials

• After multiple trials have been conducted and similar results have been achieved, the researchers can choose to accept or reject their hypothesis. After analyzing their results and perhaps coming up with a scientific theory, scientists might choose to expand the experiment to test other variables or components. The previous experiment can yield further questions and reasons for investigation, and then the process is repeated. Proving reproducibility with multiple trials allows researchers to have the confidence to build on the former experiment.