Supporting adolescents with self-harm: a brief psychological intervention to reduce self-harm in adolescence

Current primary outcome measure as of 11/07/2025:
Self-reported episodes of self-harm within the past month, assessed 6 months post-randomisation. This is a count outcome based on summing the number of episodes of self-harm reported from a single item (“How many times in the past month?”) across the three behavioural domains (suicide attempt, self-harmed without intent to end life, self-harm with ambiguous intent) from the modified version of the Short Form of the Self Injurious Thoughts and Behaviour Interview (SITBI, Nock et al., 2007).

Previous primary outcome measure:
Number of self-harm episodes during the past month measured using a modified version of the Self-Injurious Thoughts and Behaviours Interview Short Form at baseline and 6 months

Current secondary outcome measures as of 11/07/2025:
1. Depressive symptoms, measured by the short version of the Moods and Feelings Questionnaire (MFQ) at baseline and 6 months
2. Anxiety symptoms measured by the Generalised Anxiety Disorder Assessment (GAD-7) at baseline and 6 months
3. Repeat ED attendance due to self-harm: identified in ED medical records, measured by count at baseline and 6 months
4. Death by suicide, i.e., cause of death is intentional self-harm or undetermined intent, identified in NHS records, captured at 6 months
5. School attendance, obtained from the Client Service Receipt Inventory (CSRI), obtained at baseline and 6 months
6. General wellbeing measured by the Warwick-Edinburgh Mental Wellbeing 14-item scale at baseline and 6 months
7. Three separate domains of self-harm behaviour assessed by the modified SITBI Short Form: number of reported episodes of self-harm with suicidal intent, self-harm without suicidal intent, and self-harm where intent is ambiguous, in the past month, at baseline and 6 months
8. Three separate domains of self-harm related suicidal ideation assessed by the SITBI Short Form: number of reported episodes of suicidal ideation, suicide plans, and thoughts of non-suicidal self-injury in the past month, measured at baseline and 6 months
9. Dichotomized self-harm (any self-harm in the past month) assessed by the SITBI short form, at baseline and 6 months
10. Number of young person reported self-harm episodes obtained every two weeks for the duration of 6-month follow-up via text message survey where provided
11. Parent/carer self-reported health-related quality of life assessed by the ED-5D-5L at baseline and 6 months
12. Children’s self-reported health-related quality of life data collected using Child Health Utility 9D (or CHU9D) at baseline and 6 months

Other variables:
1. Experiences of care in the ED assessed by a version of the Negative Effects Questionnaire, developed for a similar trial in adults, the ASSURED trial, captured at baseline
2. Parental/carer involvement in care received as part of the Intervention or Treatment as Usual (binary variable), captured as part of a bespoke form designed specifically for the SASH trial

Other data that will be extracted from records:
1. Co-occurring mental disorders
2. Young people and carer participants' sociodemographic and clinical baseline data from medical records will be complemented with interviews.

Resource use will also be assessed:
1. Resources to train SASH Practitioners and resources involved in delivering SASH and TAU will be collected using two Health Economics Inventory forms designed for the SASH trial
2. Health and social care service use and school support services use by young people will be assessed using the CSRI
3. Productivity loss and family resource use due to the mental health difficulties of young people will be assessed using the CSRI


Previous secondary outcome measures:
1. Depression measured by the short version of the Moods and Feelings Questionnaire (MFQ) at baseline and 6 months
2. Anxiety measured by the Generalised Anxiety Disorder Assessment (GAD-7) at baseline and 6 months
3. Repeat ED attendance due to self-harm: identified in ED medical records, measured by count at baseline and 6 months
4. Death by suicide, i.e., cause of death is intentional self-harm or undetermined intent: NHS /local authority/coroner records, captured at 6 months
5. School attendance, obtained from the adolescent’s school, measured by count at baseline and 6 months
6. General wellbeing measured by the Warwick-Edinburgh Mental Wellbeing 14-item scale at baseline and 6 months
7. Experiences of care in A&E measured by the adapted Negative Effects Questionnaire (NEQ) at baseline
8. Separate dimensions of self-harm measured by the Self-Injurious Thoughts and Behaviors Interview (SITBI) Short Form): Number of reported episodes, in the past month, of the below, measured at baseline and 6 months:
8.1. Self-injury without suicidal intent
8.2. Suicide attempts
8.3. Self-injury with unclear or ambiguous intent
9. Dichotomized self-harm (any self-harm in the last month) measured by the SITBI Short Form at baseline and 6 months
10. Additional dimensions of self-harm measured by the SITBI Short Form: Number of reported episodes, in the last month, of the below, measured at 6 months:
10.1. Suicidal ideation
10.2. Suicide plan
10.3. Thoughts of non-suicidal self-injury
11. Number of self-harm episodes reported via text message survey (Ecological Momentary Assessment) every 2 weeks

Resource use:
1. Health and quality-adjusted life-years (QALYs) measured and calculated using the Child Health Utility 9D (CHUD9) at baseline and 6 months
2. Cost of health and social care services use for children measured by the Client Service Receipt Inventory adapted for young people, collected by either the young person or parent/guardian (if applicable) according to participant preference, measured at baseline and 6 months
3. Costs of productivity lost and out-of-pocket service for guardians measured by the Client Service Receipt Inventory at baseline and 6 months

Parent-reported data:
1. Guardians’ self-reported health-related quality of life measured using EQ-5D-5L at baseline and 6 months
2. Cost of health and social care services use for children as measured by Client Service Receipt as detailed above, at baseline and 6 months