Statistical significance and clinical significance
- Statistical significance is the likelihood that results obtained were not due to chance.
- Tests of significance estimate the probability that the results are reproduceable.
- Data which does not reach statistical significance are too weak to reach any conclusion.
- Just because a result achieves a p-value of 0.05, that does not make it important.
- Statistical significance says nothing about effect size - miniscule effects can creep in under a p-value of 0.05.
- Clinical significance is the practical importance of a treatment effect.
- Clinical significance implies that the difference between treatments in effectiveness is clinically important, and it is possible that clinical practice will change if such a difference is seen.
- Statistical significance is used to to inform clinical significance.