Does insecure attachment affect treatment outcome in young persons with post-concussion symptoms? A secondary analysis of the GAIN trial

• Insecure attachment may negatively affect symptom reporting and disability in illness. • Research on insecure attachment and treatment outcome after a concussion is lacking. • We explored if insecure attachment impact intervention for post-concussion symptoms. • Overall the evidence for insecure attachment to affect treatment outcome was weak. • Patients with fearful attachment could be a subgroup with less favourable outcome.