A comparison of motion sickness prevalence between seafarers and non-seafarers onboard naval platforms.

BACKGROUND Motion sickness may crucially affect the operational performance of soldiers at sea and this differs between individuals and environments. OBJECTIVES To report on the prevalence and understand the risk factors for motion sickness among Singaporean sailors (seafarers) and attached army servicemen (non-seafarers) onboard naval platforms. METHODOLOGY Cross sectional study using self-administered survey of 503 personnel over the monsoon period from January to April 2001. RESULTS The prevalence of motion sickness was distinctly higher in the army (59.2%) personnel compared with the navy (38.3%) over a series of sea states. The most common symptoms were headache, nausea and dizziness. The Motion Sickness Susceptibility Questionnaire was used to score susceptibility and appeared to correlate better among non-seafarers rather than seafarers. The discomfort experienced in one's environment was perceived to contribute towards onset and smoking appeared to be protective against motion sickness. Regular sailing appears to be an important factor in minimising motion sickness. CONCLUSION While we understand motion sickness to be a continuum of physiological responses to the whole body vibration, it is especially apparent among the non-seafarers. Seafarers by themselves will become less susceptible with regular sailing and they are also more cognizant of the modalities available to alleviate symptoms.