# Cost-effectiveness and cost-utility of a therapist-guided online intervention provided soon after trauma: Results from a randomized controlled trial

## TL;DR

A therapist-guided online therapy called CIPE, given soon after trauma, reduces stress symptoms and is cost-effective for society.

## Contribution

CIPE is a new early digital intervention that shows strong cost-effectiveness and sustained benefits for trauma survivors.

## Key findings

- CIPE reduced post-traumatic stress symptoms at 3- and 7-week follow-ups.
- CIPE had a 95% probability of being cost-effective at €939–1181 per additional responder.
- Effects of CIPE were sustained at a 12-month follow-up.

## Abstract

This study evaluated the cost-effectiveness and cost-utility of a therapist-guided, internet-delivered early intervention for trauma. Exposure to traumatic events is common and can lead to substantial psychological distress, functional impairment, and societal costs. Early psychological interventions have the potential to mitigate these effects. We developed Condensed Internet-delivered Prolonged Exposure (CIPE), a digital intervention delivered within two months of trauma exposure. In a randomized controlled trial (N = 102), CIPE was more effective than a waiting-list control in reducing post-traumatic stress symptoms at post-intervention (3 weeks) and at a prespecified 7-week follow-up while the waiting-list control remained intact (prior to crossover). In this study, we evaluated CIPE from a societal cost perspective, aggregating direct medical costs (healthcare contacts, medication) and indirect costs (sick leave, reduced productivity, domestic loss) with equal weight in total cost calculations using a self-report questionnaire. Cost-effectiveness was assessed using responder status (≥10-point symptom reduction) and subthreshold symptom status on the PTSD Checklist for DSM-5. Cost-utility was assessed using quality-adjusted life years (QALYs) from the EQ-5D. Incremental cost-effectiveness ratios (ICERs) were estimated using bootstrapped regression analyses and visualized in cost-effectiveness planes and acceptability curves. CIPE showed a 95 % probability of being cost-effective at a willingness-to-pay threshold of €939–1181 per additional responder or subthreshold case. The corresponding cost per QALY gained was €2929–3636. Effects were sustained at 12-month follow-up. These findings suggest that therapist-guided digital exposure therapy delivered soon after trauma can reduce symptoms at a relatively low cost to society. Future research should examine CIPE's long-term economic impact and potential for broader implementation.

•CIPE is a 3-week, therapist-guided digital intervention soon after trauma that reduced posttraumatic stress symptoms at 3- and 7-week follow-ups•CIPE showed a 95% probability of being cost-effective versus a waiting-list control.•One QALY gained with CIPE costs €2929 to €3636 from a societal perspective.•Effects were sustained at 12 months, supporting early integration into mental health care.

CIPE is a 3-week, therapist-guided digital intervention soon after trauma that reduced posttraumatic stress symptoms at 3- and 7-week follow-ups

CIPE showed a 95% probability of being cost-effective versus a waiting-list control.

One QALY gained with CIPE costs €2929 to €3636 from a societal perspective.

Effects were sustained at 12 months, supporting early integration into mental health care.