Using data from Cochrane reviews, we developed two economic models:

• For adults, we assessed cognitive behavioural therapy (CBT) added to standard care.
• For young people, we looked at dialectical behaviour therapy for adolescents (DBT-A) versus standard care.

What did we find?

• CBT for adults appeared cost-effective: it provided meaningful benefits at reasonable cost levels for the NHS.
• DBT-A for children and young people, however, did not show good value for money, with very high costs compared to the health benefits.

Why does this matter?

• Self-harm is a serious health concern, often leading to repeated episodes and high healthcare costs. In a study I co-authored, we explored whether certain psychological therapies offer good value for money in preventing repeat self-harm.
• In times of limited resources, understanding which interventions offer the best health gains per pound spent can help shape better services for people who self-harm. Our findings suggest that CBT could be a good investment for adult services, while more evidence is needed regarding DBT-A for young people.
• CBT for adults who self-harm likely offers good value for money, while DBT-A for young people currently does not. Economic evidence supports using CBT in adult services, but further research is essential for youth interventions.

Study Design

• Two model-based cost-utility analyses assessed the cost-effectiveness of cognitive behavioural therapy (CBT)-informed psychological therapy for adults and dialectical behaviour therapy for adolescents (DBT-A) for children and young people (CYP) who have self-harmed.
• The models supported updates to National Institute for Health and Care Excellence (NICE) guidance.

Model Structure

• Two hybrid decision-analytical models were developed using a decision-tree followed by a three-state Markov model over a five-year time horizon.
• These models simulated health outcomes and resource use following hospital presentation for self-harm.

Interventions and Comparators

• For adults, CBT-informed psychological therapy plus treatment as usual (TAU) was compared to TAU alone.
• For CYP, DBT-A was compared to enhanced TAU, reflecting current UK practice.

Data Sources

Effectiveness estimates were sourced from Cochrane meta-analyses. Clinical inputs, including baseline risks, transition probabilities, and mortality, were derived from large UK cohort studies and expert opinion. Utility values for calculating quality-adjusted life years (QALYs) were drawn from EQ-5D data.

Analysis

Intervention costs included therapist time and healthcare resources. Analyses adhered to NICE’s reference case, discounting costs and QALYs at 3.5% annually. Probabilistic and sensitivity analyses assessed uncertainty. Expert validation confirmed model robustness. Cost-effectiveness was evaluated using NICE thresholds.