Predictors of disability in adolescents and young adults with acquired brain injury after the acute phase.

Aim: To develop and validate a prediction model for disability among young patients with acquired brain injury (ABI) after the acute phase.Methods: Within a nationwide cohort of 446 15-30-year-old ABI-patients, we predicted disability in terms of Glasgow Outcome Scale - Extended (GOS-E) <7 12 months after baseline assessment in outpatient neurorehabilitation clinics. We studied 22 potential predictors covering demographic and medical factors, clinical tests, and self-reported fatigue and alcohol/drug consumption. The model was developed using multivariable logistic regression analysis and validated by 5-fold cross-validation and geographical validation. The model's performance was assessed by receiver operating characteristic curves and calibration plots.Results: Baseline assessment took place a median of 12 months post-ABI. Low GOS-E (range 1-8 (best)) and Functional Independence Measure (range 18-126 (best)) along with high mental fatigue (range 4-20 (worst)) predicted disability. The model showed high validity and performance with an area under the curve of 0.82 (95% confidence interval (CI) 0.77, 0.87) in the cross-validation and 0.81 (95% CI 0.73, 0.88) in the geographical validation.Conclusion: We developed and validated a parsimonious model which effectively predicted disability. The model may be useful to guide decision-making in outpatient neurorehabilitation clinics treating young patients with ABI.