Look at the evidence
Evidence is central to science
Evidence is what science is all about. It’s all well and good having an idea about how the world works, but you need something to back it up. The scientiﬁc method allows researchers to test their ideas through investigations.
First, you need a question. This normally comes after some initial observations that suggest something interesting is happening or from a problem you want to solve. You can construct a hypothesis that could explain what you’ve seen and carry out an experiment to test it, then analyse the data and draw conclusions. The overall quality of any study depends on making sure each step is done properly.
Not all evidence gathered using the scientiﬁc method is the same. Quantitative data are measurable (eg length or height), and because they are numerical they can be analysed statistically. Qualitative data are descriptive (eg hair colour). Analysing qualitative data is more difficult and interpretations can be subject to personal opinion.