Standardization of clinical investigators for studies of restorative materials.

In preparation for internordic studies of the clinical performance of selected restorative materials, 11 clinicians from Denmark, Finland, Norway and Sweden were selected to participate in two clinical training sessions. The first of these sessions consisted of lectures on clinical research methodology, the content of a research protocol and specific description of the criteria to be used for clinical evaluation of Color Match, Cavo Surface Margin Discoloration, Anatomic Form, Margin Adaptation, and Caries. Demonstrations were also given in the clinical evaluation procedures. Using a rotation system at both the training sessions each participant alternatively served as patient recorder and examiner. The participants examined and rated a larger number of restorations independently in teams of two. The results of the performed examinations showed the overall agreement between all pairs to exceed 85%. The results of this study indicate that after a short introductory course, scientifically non-experienced senior clinicians can be trained to use the described system at a comparatively high overall level of precision.