The questionnaire was initially prepared by a retrospective selection of suitable items reviewed in current literature on the subject of periodontal risk factors and indicators. Research was conducted using PubMed, whereby only articles written in English were included. Systematic reviews and randomised, controlled studies were preferred. Based on this 16 questions were developed. The individual response options were assigned point values extending from zero to eight, based on their assumed degree of influence on the periodontal disease. To determine the correct wording and phrasing the questionnaire was given as a pretest to 20 patients not included in the study.