Online ride-hailing refers to the business activities of providing non-cruise booking taxi service based on a service platform that integrates information of supply and demand relying on Internet technology[1]. Compared with the traditional taxi, it has the advantages of high efficiency, good experience, convenience, low price, and so on. Online ride-hailing services are growing rapidly in many countries. Currently, DiDi, Uber, Grab, Lyft and other ride-hailing platforms have covered thousands of cities and built a global network. In China, Didi Chuxing, as the largest mobile travel platform, provided over 7.43 billion mobile trips to 450 million passengers in more than 400 cities during 2017[2]. As an emerging travel mode, online ride-hailing plays an increasingly important role in people's daily travel, the user volume of which has reached 362 million in China by March 2020[3].
Through a large number of sample surveys in China, it was found that the occupational group of taxi drivers generally has a high smoking rate [4–6]. In addition to causing various malignant tumors, respiratory system, cardiovascular and cerebrovascular system, and other systemic diseases, smoking in a narrow and closed carriage will also endanger the health of passengers and the safety during driving[7]. In 2011, the Detailed Rules for the Implementation of the Regulations on the Administration of Sanitation at Public Places issued by the Ministry of Health of the People's Republic of China stipulated for the first time the contents of smoking control in public transport. According to our statistics, at present, 90% of provincial administrative regions in China have issued policies and regulations banning smoking in public transport. However, the definition of public transport varies from city to city, and only a few provinces, such as Beijing and Sichuan province, have listed taxis as non-smoking public transportation vehicles now. Due to short appearance up to now, the positioning of online ride-hailing vehicles is still unclear, which makes it a blind spot for anti-smoking management. Moreover, according to previous research results, high rates of smoking can lead to low compliance of tobacco regulations, coupled with incomplete national policies on smoking control in online ride-hailing vehicles, so second-hand smoke exposure in the cars is inevitable. It is necessary to research the smoking status and related factors of the occupational group of ride-hailing drivers, but there is still a lack of relevant studies.
Research at home and abroad have recognized that the influencing factors of adult smoking includes gender[8–11], marital status[12, 13], educational level[14], economic level[15], social networks[16, 17], health status[18, 19], mental illness[20–22], alcohol/drug abuse and dependence[23–26], race/ethnicity[27] work pressure[28, 29], and so on. Moreover, Hu et al.[30] and Li et al.[31] pointed out that the effect of skipping breakfast, short sleep duration, and whether to participate in recreational activities and physical exercises regularly on the smoking behavior of rural residents was significant. There are specific influencing factors among a certain population. For example, it was studied that job-related stressors impacted the increase of smoking intensity and nicotine dependence of American military personnel[32]; the smoking behavior of spouses had an effect on the smoking during pregnancy of women [33]; shift work affected the smoking of manufacturing workers [34]. At present, there are limited researches on the factors influencing drivers' smoking. Norman GJ et al.[35] and Josh Martin et al.[36] reported that households and regions with low economic level were associated with lower smoke exposure rate in cars, whereas households and regions with high economic levels were associated with higher smoke exposure rates in cars. Jain NB et al.[37] showed that job title, education level, residential area, scale and location of truck transport terminals were determinants of smoking among truck transport drivers. Ozoh OB et al.[38] studied the prevalence and related factors of smoking among commercial long-distance drivers in Lagos, Nigeria, and found that smoking friends, freight driving and low educational level had a great impact on current smoking. To sum up, the factors influencing smoking in drivers, such as demographic and socioeconomic characteristics, have a lot in common with those in adults. Besides, the occupational characteristics of drivers themselves can also affect their smoking behavior.
Based on the above results of the literature research, we designed the survey questions for online ride-hailing drivers. With the development of online ride-hailing, it provides a convenient way to conduct large scale online survey. Therefore, by the platform of ride-hailing drivers, we carried out a large sample survey covering the vast majority of areas where ride-hailing services have been provided (31 provincial-level administrative regions), that could provide a comprehensive perspective on the smoking problems of ride-hailing drivers, and do help to learn different socio-economic and working characteristics that affected the smoking status of drivers. Most importantly, the risk factors for smoking behavior based on the large random sample study was able to provide real-world evidence for international tobacco control researchers.