If a single intervention comparison (study) shows that it has a good or bad effect it does not mean that is the final answer.
A single estimate of interventions rarely provides conclusive evidence and results are often available from other studies of the same interventions. These other studies may have different results or may help to provide more reliable and precise estimates of the effects.
BEWARE: The results of single estimates of effects can be misleading. Consider all of the relevant fair estimates.
REMEMBER: Think about whether there are other studies that compare the same intervention or a systematic review of all the relevant studies.