The effect of patient‐associated factors on the reproducibility of the mouth bleeding score

Patient effects on the reproducibility of dichotomous measures of bleeding tendency after probing were investigated. Large variations in this reproducibility were observed between patients. Therefore the accuracy of the mouth bleeding score, a gingival index system, also depended on the type of patient. To illustrate the effects on the prediction intervals of the mouth bleeding score, the patients were divided into two groups using cluster analysis. The prediction intervals of the mouth bleeding scores determined for each group differed considerably from one another. Categorizing patients by the average probing depth and the average chance of bleeding, measured over all sites within a patient, provided a statistical evaluation of differences between successive mouth bleeding scores while considering the effect of the patient.