Standards for reporting chronic periodontitis prevalence and severity in epidemiologic studies: Proposed standards from the Joint EU/USA Periodontal Epidemiology Working Group

Periodontal diseases are common and their prevalence varies in different populations. However, prevalence estimates are influenced by the methodology used, including measurement techniques, case definitions, and periodontal examination protocols, as well as differences in oral health status. As a consequence, comparisons between populations are severely hampered and inferences regarding the global variation in prevalence can hardly be drawn. To overcome these limitations, the authors suggest standardized principles for the reporting of the prevalence and severity of periodontal diseases in future epidemiological studies. These principles include the comprehensive reporting of the study design, the recording protocol, and specific subject-related and oral data. Further, a range of periodontal data should be reported in the total population and within specific age groups. Periodontal data include the prevalence and extent of clinical attachment loss (CAL) and probing depth (PD) on site and tooth level according to specific thresholds, mean CAL/PD, the CDC/AAP case definition, and bleeding on probing. Consistent implementation of these standards in future studies will ensure improved reporting quality, permit meaningful comparisons of the prevalence of periodontal diseases across populations, and provide better insights into the determinants of such variation.