Evaluation of the effect of interexaminer reliability in clinical trials of dental caries prevention.

Data from a 3-yr clinical trial were used to assess reliability of two dentists who, without standardizing techniques, independently examined 286 continuous participants. Only 13.1 of 128 tooth surfaces (third molars excluded) showed a change in caries status during the trial by one or both examiners' findings. Although there was poor agreement between the examiners (46.5%) on these changes, they agreed very closely on measuring the cariostatic effects in the various treatment groups because the disagreements were random and were similar among groups.