They do this to make sure that the results will be valid and reliable. They observe what happens and record the results. Often, they repeat the same test several times to ensure reliable results. To collect and review data, tools such as computers, calculators, charts, and graphs, are used. Just as in a court case, it is proven evidence that counts.
Scientists look for likely explanations by studying patterns and relationships within the evidence.
Sometimes, the evidence available is not clear or can be interpreted in other ways. If this is so, scientists look for different ways of explaining the evidence. This may lead to a new idea or question to investigate. Other scientists may then try to repeat the investigation to validate the results. Accurate measurement with suitable units is very important for both collecting and analyzing data.