Validation of a Questionnaire Based on Self-reported Periodontal Health Among Adolescents in Santiago, Chile

Objectives: Conventional clinical periodontal examination is used as gold standard during epidemiological studies on periodontal disease; however, its implementation is complex and expensive. Nowadays, self-reported questionnaires have been proposed as an effective method when implemented in epidemiological studies, due mainly to its simplicity. This study was aimed to validate a self-reported periodontal health questionnaire to be applied in adolescents belonging to Santiago, Chile, in order to propose their use for obtaining periodontal epidemiological data.
Methods: First we establishing the content validity of the questionnaire which included questions related to self-reported periodontal health, was applied in 178 adolescents (aged 12-18 years-old) to estimate the reliability of the instrument according to its internal consistency and temporal stability. Then calibrated dentists performed a periodontal examination (n=139), using the basic periodontal examination with gingival index registration. The predictive validity of need for simple periodontal treatment (NSPT=code 3) and gingivitis (G) was assessed using logistic regression by sensitivity (SS), specificity (SP) and area under the ROC-curve (ROC).
Results: A Cronbach's alpha of 0.73 and kappa-index of 0.41 to 0.76 was obtained. 5.7% of the tested individuals were healthy (code 0). From diseased people, 7.9% required NSTP and 58.8% were G. The model predictive for NSTP, with a ROC-curve=0.85 (100% SP), included: gingival bleeding during brushing, adjusted for gender, type of educational establishment, orthodontic treatment, and frequency of dental control. The predictive model for gingivitis included all of the analyzed variables.

Conclusions: The variable “presence of bleeding during brushing” was a good predictor for assessing the diagnosis either G or NSTP, suggesting their usefulness in epidemiological studies.