The development and validation of a psychological questionnaire for patients undergoing orthognathic treatment.

OBJECTIVES: To develop a questionnaire to assess the psychosocial aspects which orthognathic patients considered important regarding their dento-facial deformity. SETTING AND SAMPLE POPULATION: A multicentre, prospective, questionnaire development and validation study based in the UK. MATERIAL AND METHODS: Questionnaire development involved item (question) selection through literature review, consultation and feedback from a questionnaire development group and semi-structured interviews. A 'final' questionnaire was tested on a cross-sectional sample of 110 pre-operative and 74 post-operative orthognathic patients and a longitudinal sample of 23 orthognathic patients. Validity was tested using Rasch analysis. RESULTS: Reliability for the Hospital Anxiety and Depression Scale (HADS) section was unsatisfactory (ICC = 0.232-0.829, Cronbach alpha = 0.625-0.670), but for the well- being (ICC = 0.857, Cronbach alpha = 0.827-0.895) and expectations (ICC = 0.861, Cronbach alpha = 0.804-0.882) sections were satisfactory. The well-being section was the only section found to be valid for the pre-and post-operative samples. Responsiveness was satisfactory for the well-being scale (p = 0.001). CONCLUSIONS: A new condition-specific orthognathic questionnaire has been developed which has been shown to be reliable, valid and responsive for the well-being scale. The HADS, as tested by Rasch analysis, was found not to be valid for this orthognathic population.