A psychological programme to improve low mood in adolescence

INTERVENTION: Eligible participants will be randomised by the Kings Clinical Trials Unit (KCTU). Participants will be randomised using block randomisation via a web interface. Randomly varying block sizes will reduce the predictability of the sequence. There will be two arms and allocation will be 1:1. Both interventions will be delivered via individual therapy sessions and consist of three to four sessions, delivered by a clinical psychologist. Sessions will last up to a maximum of 90 minutes, with the possibility of young people taking breaks during the session if needed. ‘Imagery‐based cognitive behavioural intervention’ (ICBI): The intervention will combine components of (A) imagery rescripting to reduce the distress associated with negative images and build positive future images and (B) memory specificity training to increase specificity and access to memories. ICBI will follow a treatment manual and will be accompanied by a therapy workbook. ‘Non‐directive supportive therapy’ (NDST): NDST will involve planned delivery of individual sessions with an empathic, concerned professional for emotional support and discussion of participant‐initiated options for addressing problems. This intervention is designed to control for factors that, other than active components of therapy, could contribute to change such as the passage of time and non‐specific aspects of therapy (e.g. speaking to an empathic therapist). NDST will follow treatment guidelines. CONDITION: Depression ; Mental and Behavioural Disorders ; Depression PRIMARY OUTCOME: Feasibility outcome:; Feasibility and acceptability of the intervention is assessed by recording numbers of eligible participants, recruitment rate, retention rate outcome measure completion rate, data completeness, incidence of unexpected adverse events, data on adherence/compliance, and feedback questionnaires. SECONDARY OUTCOME: Principal clinical outcome; Depression is measured using the Mood and Feelings Questionnaire (MFQ; long version) pre‐therapy, post‐therapy and 3‐month follow‐up. (The short version of the MFQ will also be administered at each intervention session.) ; ; Other measures ; 1. Anxiety is measured using the Screen for Child Anxiety Related Disorders pre‐therapy, post‐therapy and 3‐month follow‐up; 2. Symptoms of post‐traumatic stress are measured using the Revised Impact of Event Scale: child version pre‐therapy, post‐therapy and 3‐month follow‐up; 3. Response style is measured using the Children’s Response Style Questionnaire pre‐therapy, post‐therapy and 3‐month follow‐up ; 4. Self‐esteem is measured using the Rosenberg Self‐Esteem Scale pre‐therapy, post‐therapy and 3‐month follow‐up; 5. Self‐Concept Clarity is measured using the Self‐Concept Clarity scale pre‐therapy, post‐therapy and 3‐month follow‐up; 6. Mental Imagery for future events is measured using the Prospective Imagery Task pre‐therapy, post‐therapy and 3‐month follow‐up; 7. Memory specificity is measured using the Autobiographical Memory Task pre‐therapy, post‐therapy and 3‐month follow‐up; 8. Daily mood is measured for seven days using daily mood ratings pre‐therapy and post‐therapy; 9. Emotional response (subjective ratings and heart rate variability) to autobiographical memories is measured using a positive memory recall task pre‐therapy and post‐therapy INCLUSION CRITERIA: 1. Aged 16‐18 2. Informed consent 3. Willing and able to engage in psychological therapy and complete assessments 4. Scoring above clinical cut‐off on Mood and Feelings Questionnaire (MFQ clinical cut‐off = 20).