Development of a patient-reported outcomes and experience measure for Orthognathic surgery: validation of the Northwick Park Orthognathic Questionnaire (NOQ).

Abstract Orthognathic surgery aims to correct dentoskeletal and facial discrepancies. The expected benefits are functional, cosmetic, and psychological. In a previous publication, this group assessed the determinants of patient satisfaction to formulate the Northwick Park Orthognathic Questionnaire (NOQ). The aim of the present study was to validate this questionnaire. A total of 118 postoperative patients prospectively completed the NOQ, 30 of whom completed the questionnaire a second time. The mean completion rate was 87.6 ± 10%. Response reproducibility was high: 92% of patients gave identical responses (range 81–100%). The intra-class correlation coefficient (ICC) was 0.96 (0.96 ± 0.072). Average test–retest scores for each domain were as follows (range in parenthesis): reasons for treatment 93% (60–100%), preoperative experience 96% (81–100%), preparation for surgery 95% (81–100%), inpatient experience 89% (55–100%), post-discharge experience 83% (55–100%), benefits of treatment 92% (71–100%), overall patient education 91% (62–100%). Internal validity using Cronbach’s alpha was 0.72 (standard deviation 0.23, range 0.5–1). The results confirm the consistency of responses and the reliability of the information collected with the NOQ. The NOQ is a novel questionnaire and a valid metric to quantify a patient’s perception of their experience. Its adoption may aid in making targeted improvements to patient care.