Veterans Administration Cooperative Studies Project No. 147. Part II: A new assessment system for rating metal-ceramic crowns.

The rating system developed for this study combined ordinal and numerical scoring. The method involved the following: defining the critical criteria, defining the ordinal rating criteria for the assignment, assigning numerical scores for each individual criterion and totalling the scores for each restoration, adding an adjustment number, and scaling the results to the 0-to-10 range and rounding off to the nearest tenth. When tested on sample data gathered at the 12-month followup appointment, the new system elicited a finer discrimination of differences in the quality of the restorations. Although the system fully meets the needs of the specific project, it should not be considered an answer to the needs of all clinical investigations. It should be viewed as a different approach in the development of an acceptable clinical rating system.