Table 2 Key theoretical frameworks that guided the development of the CGI

Socioecological model of child mental health

Mental health is the result of complex, dynamic interactions between processes occurring across levels of the socioecology and across time [69,70,71,72,73,74,75], including past trauma and ongoing adversity.

Research into the determinants of child mental health in CHEs provides robust support for a socioecological model of child mental health [10]. Phase 1 findings highlighted the importance of parent and community factors on child mental health outcomes.

The developing child must experience regular, repeated, and enduring interactions that influence healthy growth and development [64] which the CGI targets through parent-child interactions.

Complex trauma

Complex trauma (multiple, chronic, prolonged, severe) adversely impacts all domains of child development (physical, cognitive, emotional, behavioural, interpersonal, psychological) [76,77,78].

CHEs increase the risk of a child being exposed to multiple, chronic, prolonged and severe trauma [76, 79, 80]. Phase 1 findings described children in CHE as frequently exposed to chronic, multiple, prolonged and severe trauma.

Therapeutic approaches that support children and parents that have experienced complex trauma are prioritised (psychoeducation, self- and co-regulation skills, enhancing the attachment relationship).

Transdiagnostic approach

The relevance and validity of a diagnostic approach [81, 82] is questionable in cross-cultural, humanitarian settings [42]. Alternatively, the transdiagnostic approach, posits that similar aetiological and maintenance processes underlie many mental health disorders [83].

This approach holds promise for use in CHEs, and recent intervention protocols developed for CHEs (e.g., World Health Organisation’s Problem Management Plus) utilise this framework [84–86]. Phase 1 findings described a range of difficulties across children in CHEs that fit better with a transdiagnostic approach reflecting universal underlying psychological processes rather than culturally influenced symptoms and diagnoses.

Potential underlying transdiagnostic processes (e.g., disruption to the attachment relationship; dysregulation of arousal, affect, and behaviour) are common in children presenting to MSF [87] and are targeted in the CGI for potential benefit across a range of presenting difficulties.