Health trajectories of international humanitarian aid workers: growth mixture modelling findings from a prospective cohort study.

Most iHAWs stayed healthy during their assignment; a stable 'ill health' trajectory was identified for most health indicators. Sense of coherence is an important mechanism for understanding the health of all iHAWs in the different health trajectories, including the 'healthy' profile. These findings give new possibilities to develop activities to prevent worsening health and help strengthen iHAWs' ability to remain healthy under stress.