Results are clinically significant when they make enough difference to you and your patient to justify changing your way of doing things. For example, a drug which is found in a megatrial of 50,000 adults with acute asthma to increase FEV1 by only 0.5% ( P value.0001) has failed this test of significance.
The extent to which the results of a study will be important, useful, and applicable in the treatment of patients.
Change in a subject's clinical condition regarded as important whether or not due to the test article. Some statistically significant changes (in blood tests, for example) have no clinical significance. The criterion or criteria for clinical significance should be stated in the protocol.
a conclusion that an intervention has an effect that is of practical meaning to patients and health care providers. Even though an intervention is found to have a statistically significant effect, this effect might not be clinically significant. In a trial with a large number of patients, a small difference between treatment and control groups may be statistically significant but clinically unimportant. In a trial with few patients, an important clinical difference may be observed that does not achieve statistical significance. (A larger trial may be needed to confirm that this is a statistically significant difference.)
A statistically significant result does not necessarily imply that it is useful in a clinical setting (does the treatment reduce a patients' blood pressure by a worthwhile amount? Does it help the patient?). Clinical significance is a matter of judgement taking into account the clinical importance and applicability of the results.
Getting statistical significance is not necessarily the end of the story. In a clinical trial you would also want to see clinical significance, which is not always present. In clinical terms, the statistically significant difference may be so small as to be irrelevant. Note that we may see clinical significance in a sample, but we cannot conclude that this is a real effect in the population unless we also have statistical significance.
The statement that something is clinically important.