Adjunctive Bright Light Therapy in Adolescents With Depression and Eveningness

Inclusion Criteria: 1. Chinese, aged 12-19 years old; 2. Written informed assent/consent of participation into the study is given by the participant and his/her parent or guardian (for those aged under 18), respectively; 3. Having a DSM-5 diagnosis of unipolar non-seasonal depression as confirmed by the Chinese version of the Kiddie-Schedule for Affective Disorders and Schizophrenia (K-SADS) psychiatric interview, DSM-5 Seasonal specifier, AND having a score on Children's Depression Rating Scale (CDRS-R) at least 40; 4. Being classified as evening chronotype according to the score on the reduced Horne-Östberg Morning-Eveningness Questionnaire (rMEQ), i.e. \<12. Exclusion Criteria: 1. A current diagnosis of substance abuse or dependence; a current or past history of manic or hypomanic episode, schizophrenia spectrum disorders, organic mental disorders, or intellectual disabilities; 2. Having a clinically significant suicidality (presence of suicidal ideation with a plan or an attempt) as assessed by K-SADS; 3. Having been enrolled in any other clinical trial investigational products within one month at the entry of the study; 4. Initiation of or change in antidepressant medication within past 4 weeks; 5. Having been or is currently receiving any structured psychotherapy; 6. With hearing or speech deficit; 7. Night shift worker; 8. Trans-meridian flight across at least two time zones in the past 3 months and during the study; 9. Presence of an eye disease, e.g., retinal blindness, severe cataract, glaucoma.