Intervention plans in the two youth social services
| Phase | Intervention | MYSS | MYSS-IU |
| Immediate phase (0–4 hours) | Physical security of victims and first aid by the staff present | ✓ | ✓ |
| Psychological first aid | By the staff present and by the IS | By the staff present | |
| Session of individual or group verbalisation | ✓ | ||
| Inform the hierarchy | ✓ | Evaluation of the need for a coordinating committee or postvention by the management | |
| Postimmediate phase (4–72 hours) | Assessment of the state and needs of the victims and witnesses by the IS | ✓ | ✓ |
| Inform the HSO | And of all at-risk workers by the IS | By the IS | |
| Offer different external options of support | ✓ | ✓ | |
| Offer internal support (peer support) | For the peer support cohort only | ||
| Solicit a specialist in postvention if necessary by the HSO | ✓ | ||
| Support in administrative and justice procedures | By the HSO | By the IS | |
| Vigilance and re-evaluation of the needs if necessary | ✓ | ✓ | |
| Application of administrative measures if necessary (two paid sick days) | ✓ | ||
| Midterm phase (72 hours and more) | Use of an external assistance resource if necessary (employee assistance programmes) | ✓ | ✓ |
| Participation in individual meetings of victims conducted by a peer support member | For the peer support cohort only | ||
| Coordination of maintenance and reintegration strategies for employment by the HSO in collaboration with the IS | ✓ | ||
| Vigilance, re-evaluation of the needs and offer additional support by the IS | ✓ | ||
| Arrangement of the working conditions and support to return to work if necessary by the IS | ✓ | ||
| Postevent analysis | By the IS and the HSO | By the IS |
HSO, Heath and Security Office; IS, immediate superior; MYSS, Monteregie Youth Social Services; MYSS-UI, Montreal Youth Social Services-University Institute.