The concept comes from Judith Herman, in 1992, and was formally included in ICD-11 in 2018. What differs from classic PTSD is not severity but the duration and nature of exposure: childhood abuse, prolonged domestic violence, captivity — repeated situations with no exit, usually caused by someone you depended on.
The ICD-11 diagnosis requires the PTSD criteria plus three further disturbances, together called “disturbances in self-organisation”: emotional dysregulation (intense reactions that are hard to settle, or the opposite — numbness), negative self-concept (persistent shame, a sense of being fundamentally flawed) and relational difficulties (avoiding closeness, or unstable relationships).
Why the distinction matters: a treatment focused solely on the traumatic memory is often too much, too soon, for someone whose regulatory capacity has been eroded over years. Complex-trauma protocols work in phases — first stabilisation and regulation skills, only then memory processing, then reintegration.
Recovery is possible, but on a different time horizon. Anyone expecting twelve sessions for twenty years of exposure is set up for disappointment.