# PREDICTING EFFECT AND EVALUATING COST-EFFECTIVENESS OF A FAMILY INTERVENTION AFTER ACQUIRED BRAIN OR SPINAL CORD INJURY: A RANDOMIZED CONTROLLED TRIAL

## TL;DR

This study evaluated a family intervention for people with brain or spinal cord injuries and found it to be potentially cost-effective, with little influence from factors like injury type or delivery format.

## Contribution

The study introduces a novel evaluation of a family intervention's cost-effectiveness and predictors of treatment response in acquired brain or spinal cord injury recovery.

## Key findings

- Injury type, time since injury, delivery format, and participant role had negligible to small effects on treatment response.
- The intervention had an incremental cost of €798.16 and a high probability of being cost-effective at a €300 willingness-to-pay threshold.
- The Mental Component Summary improved by 5.64 points at 2 months' follow-up.

## Abstract

To predict treatment response of a family intervention and investigate its cost- effectiveness from a healthcare payer perspective.

Explorative predictor analyses and trial-based economic evaluation.

Participants (n=157) were enrolled 4 months to 2 years after discharge from a specialized neurorehabilitation unit.

Injury type, time since injury, delivery format, and relationship (individual with injury vs family member) were explored as predictors of effect using linear mixed-effect regression. Cost-effectiveness was analysed from a healthcare payer perspective, with incremental cost based on delivery. Incremental health effect was reported for measures on mental health and anxiety and depression symptoms.

The 4 predictors had negligible to small effects on the treatment response. Incremental cost for the family intervention was estimated at €798.16 (CI: €700.9; €895.5). Incremental health effect was estimated at 5.64 (CI: 2.71, 8.56) points on the Mental Component Summary at 2 months’ follow-up. At a willingness-to-pay threshold of €300, the probability of the intervention being cost-effective was 99.8% for the Mental Component Summary.

The predictors showed no or little effect on the treatment response, and the cost-effectiveness analysis showed the probabilities of the intervention being cost-effective from a health payer perspective.

Acquired brain or spinal cord injuries present significant challenges not only for the affected individual but also for their family. This study evaluated a manualized family intervention consisting of 8 sessions facilitated by neuropsychologists, in which the entire family participated. The aim was to identify factors that might explain variability in treatment outcomes and to assess the cost-effectiveness of the intervention. A total of 157 participants were included: 73 individuals with an injury and 84 family members. Injury type, time since injury, delivery format, and participant role (injured individual vs family member) had little to no influence on the intervention outcomes. Moreover, the intervention demonstrated a high probability of being cost-effective, taking into account both the direct costs of the intervention and indirect costs related to participants’ time and transportation.