The aim of this study is to investigate the validity, reliability, and responsiveness of the Cognitive Exercise Therapy Approach-Biopsychosocial Questionnaire (BETY-BQ) in individuals with temporomandibular disorder. The following are alternative hypotheses of the study: * BETY-BQ has significant convergence with the Patient Health Questionnaire-9 measuring depression. * BETY-BQ has significant convergence with the Patient Health Questionnaire-15 measuring physical symptoms. * BETY-BQ has significant convergence with the Generalized Anxiety Disorder-7 measuring anxiety. * BETY-BQ has significant convergence with the Short Form-36 measuring quality of life. * BETY-BQ has significant convergence with the Craniomandibular Pain and Disability Inventory measuring disability. * BETY-BQ has significant convergence with the Mandibular Function Impairment Questionnaire measuring function. * BETY-BQ has significant stability. * BETY-BQ has significant internal consistency.