There are many other examples of gabs in the knowledge in the maritime health and safety area, just to mention some of them:

Incidence rates of occupational injuries,

Prevalence of occupational diseases, 

Noise levels on ships

Prevalence of hearing loss,

Risk of injuries due to fatigue, also from jet-lag,

Risk of exposure to toxic chemicals,

HIV risk in seafarers from high risk areas

Malaria and many other research questions …