Introduction Previous studies have shown that Early Service Leavers (ESL) are at increased risk of adverse socio-economic outcomes such as unemployment, homelessness and crime, as well as poor mental health. The Scottish Veterans Health Study enabled exploration of long-term health outcomes in relation to length of service. This paper presents a comparison of the health of ESL with both longer-serving veterans and with non-veterans, and explores implications for transition.

Methods Retrospective cohort study of 57,000 veterans and 173,000 people with no record of service, born between 1945 and 1985 who were resident in Scotland, matched for age, sex and geographical region, and stratified by length of service for veterans, followed up for up to 30 years. Health outcomes were compared using survival analysis methodology (Cox proportional hazards).

Results The veteran cohort included 14,000 ESL, of whom 6,000 failed to complete initial training. People who were older at recruitment were more likely to become ESL. ESL were at higher risk of smoking-related disease than either longer-serving veterans or non-veterans. For alcohol-related outcomes, the risk was only increased in ESL who completed training. ESL were not at increased risk of drug misuse. The highest risk of PTSD was in ESL who did not complete training, whilst veterans with the longest service were at lower risk than non-veterans.

Conclusion The Scottish Veterans Health Study has confirmed the poorer health outcomes of ESL reported in earlier studies. It is unlikely that military service is causal, and it is more likely that it represents a selection effect. The early weeks of training may act as a filter for those who are unsuited to military service, resulting in a ‘less healthy leaver effect’ which mirrors the ‘healthy worker effect’ in longer-serving people. Ensuring that ESL transition into new employment may help to minimise adverse outcomes.