Abstract
BACKGROUND: Self-reported measures of periodontitis developed for use in population surveillance are increasingly used in causal research. Numerous studies evaluate the validity of these measures against clinical parameters of periodontitis, yet few include validation parameters outside of multivariable models. Individual item validity is necessary to adequately inform use of these measures in causal research. METHODS: We used data from the National Health and Nutrition Examination Survey 2011-2014 in which dentate participants completed full-mouth periodontal examinations (N = 6966). We evaluated six self-report questionnaire items related to periodontal disease status against periodontitis case definitions developed by the Centers for Disease Control and Prevention and American Academy of Periodontology (CDC-AAP). We estimated the sensitivity and specificity of individual items using severe and moderate-to-severe periodontitis classifications. We additionally combined items to evaluate the validity of joint measures. RESULTS: Sensitivity was highest when measures were evaluated against severe periodontitis. Self-rated oral health of fair/poor demonstrated the highest sensitivity for severe (0.60) and moderate-to-severe periodontitis (0.48). Specificity was highest when evaluated against moderate-to-severe periodontitis, with self-reported history of tooth mobility as the most specific measure (0.87 for severe disease; 0.92 for moderate-to-severe) followed by a history of bone loss (0.88 for severe; 0.91 for moderate-to-severe). Combining questions generally improved specificity at the expense of sensitivity. CONCLUSIONS: Our findings related to item-specific validity and the associated clinical profiles facilitate needed considerations for the use of self-reported measures of periodontitis in causal research. Additionally, item-specific validity can be used to inform assessments of misclassification bias within such investigations.