Validity of a self-reported periodontal disease measure

Objectives: The purpose of this study was to determine the validity of a self-reported periodontal disease measure for use in the Health Professionals Follow-up Study. Methods: Participating dentists responded to the question ''Have you had periodontal disease with bone loss?'' Radiographs obtained from 140 participants were evaluated for bone loss at 32 posterior sites and used as the standard. A site was positive if it had bone loss 12 mm and/or complete loss of crestal lamina dura. To avoid falsely classifying participants as positive, three blinded examiners independently evaluated each participant's radiographs. An a priori decision rule was used to classify a participant positive if all examiners independently assessed the same two or more sites positive. Results: The validity of the self-reported measure was good among dentists, with positive and negative predictive values of 0.76 and 0.74, respectively. Among nondentists, the self-reported measure showed discriminately power by confirming associations with known risk factors such as age and smoking. Conclusions: Dentists have a good perception of their periodontal status, and there is reasonable consensus among dentists regarding the threshold for defining periodontal disease. Self-reported measures might have potential for use in studies of other populations with substantial cost reduction, and deserve further evaluation.