Development and validation of temporomandibular joint ankylosis quality of life questionnaire

The patient-reported outcome measures are endorsed for better evaluation of disease impact and treatment outcomes. Temporomandibular joint (TMJ) ankylosis has been observed to adversely impact the quality of life (QoL) of the patients, affecting both the physical and psychosocial aspects of their lives. The study was conducted to develop and validate a TMJ ankylosis specific QoL questionnaire (TMJAQoL). It had two phases. Phase 1 was associated with the development of the questionnaire while phase 2 examined its psychometric properties and validated the instrument. In phase 1, a 65 item pool was generated and was eventually reduced to a 37 item pool after sequential evaluation by two expert groups. The 37 item draft was subjected to item reduction by the impact method, resulting in a 12 item draft divided into 4 domains, which formed the TMJAQoL questionnaire. In phase 2, the TMJAQoL was completed by 51 TMJ ankylosis patients and was found to have optimum validity, reliability and internal consistency. 44 of these patients completed the TMJAQoL again after the surgery. A significant change in mean cumulative TMJAQoL scores (pre-op = 14.10, post op = 4.05, p = .001) was found after the surgery. This change was significantly correlated to the improvement in the maximal incisal opening and the right and left lateral movements (r > .30). Amongst the TMJAQoL domains, significant improvement was seen in functional limitation (p = .026), psychological well being (p = .017) and social wellbeing domains (p = .038). Overall, improved QoL was observed after the TMJ surgery. The TMJAQoL demonstrated optimum psychometric properties and promises to be an effective QoL instrument for the TMJ ankylosis patients.