An international survey on the incidence and modulating factors of carsickness

•46% of car passengers report some level of carsickness in the past five years.•Including childhood experiences, this rate increases to 59%.•The highest incidence was reported in China, the lowest in Germany.•Incidence differs consistently by age and gender (female > male; young > old).•Main modulating factors are driving dynamics, visual activities, low air quality. About two in three people have experienced carsickness at some point in their life (Reason & Brand, 1975). Little is known about current numbers of sufferers, cultural differences, or which modulating factors are being perceived as most relevant. Therefore, given a global increase of interest in carsickness driven by the development of automated vehicles, this survey intended to assess the status quo of carsickness in different parts of the world. We conducted an online survey with N = 4,479 participants in Brazil, China, Germany, UK and USA. 46% of participants indicated they had experienced some degree of carsickness in the past five years as a passenger in a car. When including childhood experiences, this rate increased to 59%, comparable to the 1975 findings by Reason and Brand. The highest and lowest incidence of carsickness was reported in China and Germany, respectively. In all countries, men and older participants reported a lower incidence of carsickness as compared to females and younger participants. The main modulating factors were found to be driving dynamics, visual activities, and low air quality. This study showed that carsickness still affects about 2/3 of passengers and discusses how its occurrence relates to in-transit activities and other modes of transport. The research provides a sound basis to further study how carsickness develops and to investigate countermeasures to potentially reduce it.