CBT-I Versus CBT-I+ACT for Youths With Insomnia and Anxiety

Inclusion Criteria: Youth who meet the following criteria would be eligible for taking part in this trial: i. Chinese youth aged 15-24 years old, ii. Presence of insomnia problems as defined by insomnia severity index (ISI) using cut-off of 9, which has been locally validated cut off for detecting clinical insomnia), iii. Presence of anxiety features as defined by General Anxiety Disorder-7 (GAD-7) using cut-off of 10 for detecting clinical anxiety, iv. Ability to listen, speak, and read Chinese and Cantonese, and v. Written informed consent of participation into the study is given by youth and his/her parent's if under 18 years old; In addition, individual assent will also be obtained for subjects under age 18 years old vi. Possession of smartphone Exclusion Criteria: A youth would be excluded from the study if meeting one or more of the following criteria: i. A clinical diagnosis of psychosis, schizophrenia, bipolar disorders, or intellectual disability ii. Having a diagnosed sleep disorder (e.g. delayed sleep phase and narcolepsy) that may potentially contribute to the disruption of sleep quantity and quality as determined by validated Diagnostic Interview for Sleep Patterns and Disorders (DISP) iii. Having a clinically significant suicidality (presence of suicidal ideation with a plan or an attempt) as assessed by The Structured Clinical Interview (SCID) iv. Currently receiving psychological treatment and/or pharmacological treatment for insomnia or anxiety disorder.