Abstract
The aim of this research was to identify personal and environmental factors influencing individual susceptibility to motion sickness during road transport. A questionnaire survey of 3256 coach travellers was conducted. Information on passenger characteristics, travel regularity, activity during travel, use of antimotion sickness drugs and self-reported motion sickness susceptibility were collected over 56 private hire coach journeys. Details of the travel environment (visibility, temperature and seating) were also recorded. The relationship of these variables with passenger illness and more specific symptoms of motion sickness are examined. Overall, 28.4% of passengers reported feeling ill, 12.8% reported nausea and 1.7% reported vomiting during coach travel. Travel sickness decreased with increasing passenger age and greater travel experience. Females were more likely to report feeling ill during coach travel than males by a ratio of four to three. Poor forward visibility was found to increase sickness. Passenger illness occurrence was approximately three times higher for passengers with no view of the road ahead (mean, 34.6%) compared to passengers who could see the road ahead extremely well (mean, 12.7%). No relationships were found between the occurrence of travel sickness and temperature or time of travel. Differences in the pattern of sickness responses exhibited by coach travellers suggest: (1) habituation through greater travel regularity may occur independently of reductions in travel sickness that occur with age; (2) females are more affected by poor forward visibility than males; and (3) the incidence of travel sickness could be significantly reduced by improving the external visibility afforded to passengers.