The clinical significance of new therapies for the management of periodontal disease.

With the approval of interventions or treatments for periodontal disease based on results of large clinical trials, it is often difficult for the clinician to determine whether the statistical results obtained from these studies are clinically significant and whether these interventions or treatments will thus be effective in their individual patients. In this article, a series of measures of clinical significance are derived from the literature, and a 2-step approach is suggested for determining clinical significance. First, the reliability of the data as a function of the reliability of the measurement tool(s) is calculated, and then clinical significance is put into the context of effect size. By using these estimators, clinicians can determine, for example, whether administration of an experimental local medication plus scaling and root planing provides a clinically significant outcome, which can assist them in deciding which interventions are most effective for their patients.