Application of the Delphi technique to derive a TMD taxonomy

Objectives: There is a lack of consensus on how many temporomandibular disorders (TMD) exist. The Delphi technique can be used to derive a TMD taxonomic system.

Methods: The Delphi technique is a process of reaching a consensus by the solicitation and comparison of the anonymous views of experts resulting in the “collective judgment of a group of experts on the given topic” (Brender et al. 2000). Using this method, a panel of experts independently rates options in a given subject and the process is repeated, with the participants apprised of the outcome of each reiteration, until there is a consensus. For this study, the expert panel was composed of 14 TMD clinicians at the University of Minnesota who were e-mailed a list of 47 potential disorders and were asked “How important to you are the following diagnoses in a TMD classification system on an 11-point rating scale from 0 “completely unimportant” to 10 “extremely important?” In addition, the panelists could suggest additional disorders to be included in the next Delphi round. Three Delphi rounds achieved a consensus among the panelists defined a priori by a Cronbach's alpha of ³0.90 which characterized the panelists ratings' homogeneity. Disorders with a ³9 median on the 0-10 scale from the final round were included in the taxonomic system.

Results: The panelist provided 3 additional disorders. Of the 50 disorders rated, 15 reached a median rating of 10 and 10 additional disorders had a rating of 9. Myalgia/Myofascial Pain, Arthralgia, Disc displacement/Internal derangement without Reduction with Limited Opening, and Dislocation were the disorders with the highest agreement.

Conclusion: The Delphi technique is a promising approach to be included in future TMD taxonomic projects involving a more diverse group of TMD experts with clinical and research backgrounds.