title: Letter to the editor: authors' response.
authors.affiliation: Department of Statistics and Operations Research, Oral Sciences Research Group, School of Medicine and Dentistry, University of Santiago de Compostela, Santiago de Compostela, Spain.
authors.forename: Maria Angeles
authors.initials: MA
authors.lastname: Casares-De-Cal
authors.forename: Inmaculada
authors.initials: I
authors.lastname: Tomás
mesh_terms: D005260:Female; D006801:Humans; D008297:Male; D010510:Periodontal Diseases / Q000145:classification*; D010512:Periodontal Index