The methods of paired comparisons and direct ranking were applied to the study of the relative severity of three dental problems and nine problems concerning general health, material affairs, and psychologic well-being. Subjects (n = 51) were men and women, psychology freshmen. Direct ranking and paired comparison resulted in highly comparable overall orderings of the 12 problems. It appeared that all subjects were consistent in their comparative pairwise choices. Agreement between judges was statistically significant also, but the results indicated large individual differences. Subjects judge the severity of the three dental problems to be less than the severity of the other problems. There were no significant differences between the judged severity of the three dental problems among themselves. In the discussion several possibilities for future research are mentioned.

The importance of dental problems in comparison with general health problems and psychological problems was judged by 642 adolescents. The methods used were paired comparison and direct ranking of nine stimuli. Adolescents were quite consistent in their choices. The agreement within the group was statistically significant. Adolescents judged dental problems as less important than general health problems and as more important than psychological problems. The correlation between the methods of paired comparison and direct ranking was high. The results were compared retrospectively with findings from a study of 51 older subjects. Adolescents and adults did not differ much from each other except for the ordering of the nine problems. Adults ranked dental problems as the least important.

The relative severeness of toothache and two non-dental symptoms (headache, stomach complaints) was judged by men and women (n = 47). Each symptom was specified for two frequencies of occurrence (from time to time and regular) and two levels of intensity (minor and heavy). The methods used were paired comparisons and direct ranking of the 12 (3 X 2 X 2) verbal stimuli. Subjects were highly consistent in their pairwise choices. Agreement between judges was also highly significant. The overall ordering of the severity of the stimuli showed a perfect correspondence between the two methods. 'Heavy regular headache', 'heavy regular stomach complaints', and 'heavy regular toothache' were the three symptoms judged most severe. Headache, stomach complaints and toothache, specified as low on frequency and intensity, were judged least severe. Log-linear model fitting showed that the influence of intensity on the preference of a symptom is independent of the frequency of occurrence, and vice versa.

Almost 5 million Dutch National Health Service members visit the dentist half-yearly in order to keep their so-called "dental fitness certificate" valid. The methods of paired comparisons and direct ranking were used to study the relative importance of eight oral conditions for a fit dentition: plaque, calculus, gingivitis, a pocket, a cavity, a root/radicle, a fistula and an extraction diastema. The assessments were made by a sample of Dutch general practitioners under contract to the National Health Service (n = 49). Each dentist was consistent in his comparative pairwise choices. Although agreement between the dentists was statistically significant, the low coefficient indicated individual differences between the dentists. The average rank orders of the eight oral conditions obtained from the dentists as a group by means of the two methods were highly comparable. To obtain dental fitness the dentists judged the treatment of a fistula and gingivitis more important than the treatment of plaque, calculus and cavities, and least important, the three conditions: root/radicles, pockets and extraction diastema. This average rank order indicates a shift in the concept of "dentally fit" as stated in the requirements, dating back to 1960, for granting a dental fitness certificate.