Validity and reliability of a newly developed quality of life questionnaire for patients with chronic oral mucosal diseases

Introduction: The aims of this study were to test the validity and reliability of a newly developed discipline-specific questionnaire, the Chronic Oral Mucosal Diseases Questionnaire (COMDQ), to measure quality of life in patients with chronic oral mucosal conditions. Materials and methods: Two patient samples were recruited for the purposes of this study. First, a random sample of 160 patients attending the Oral Medicine Unit of Cork University Dental School and Hospital with the following chronic oral mucosal conditions, recurrent aphthous stomatitis, oral lichen planus, the more common vesiculobullous conditions (mucous membrane pemphigoid and pemphigus vulgaris) and orofacial granulomatosis. Second, the COMDQ was randomly distributed to a sample of 100 patients without a chronic oral mucosal condition. Convergent and discriminative validity and internal consistency of the newly developed questionnaire were assessed. Results: This study has demonstrated that the newly developed questionnaire has good convergent validity with Pearson correlation coefficient of 0.819 with Oral Health Impact Profile-14 and 0.883 with Visual Analogue Scale for pain scores. The discriminative validity was also good with statistically significant differences between patients with chronic oral mucosal conditions and without chronic oral mucosal conditions. The new instrument has also demonstrated excellent reliability with Cronbach's alpha of 0.929. Conclusions: In conclusion, this study has demonstrated that the COMDQ is a valid and reliable measure to assess quality of life in patients with chronic oral mucosal diseases and therefore will be a valuable instrument in the management of these conditions.