Smoking is considered one of principal causes of preventable diseases, disability, and death all over the world [1]. Tobacco contributed to 8 million deaths globally in 2017. Approximately, 80% of these deaths occur in low and middle-income countries [2]. According to the World Health Organization (WHO, 2022), 1.3 billion adults worldwide smoke tobacco, accounting for 22.3% of the global population. 36.7% of the world’s men and 7.8% of the world’s women smoke tobacco. Although the trend of tobacco smoking is decreasing all over the world, it is still increasing in most countries of the Eastern Mediterranean Region [3]. It was reported that 60% of smokers worldwide want or intend to quit. Many of them believe in electronic cigarettes (e-cigarettes) as an efficient method to quit smoking. Nevertheless, there is no strong evidence until now about the role of e-cigarettes in helping to quit smoking, as most people use them with one or more tobacco products [4].

There are many types of smoking products used worldwide by smokers. These types include cigars, pipe smoking, hookah, and e-cigarettes. Currently, there is conflicting evidence comparing those products and their effects on health in terms of mortality and morbidity rates [5]. E-cigarettes consist of a battery, an electrical heater, and an aerosolized liquid for the user to inhale [6]. There are many types of e-cigarettes in use, such as vapes, e-hookahs, vape pens, tank systems, and mods. These types of e-cigarettes are also known as Electronic Nicotine Delivery Systems (ENDS). These ENDS include varying amounts of nicotine and harmful emissions [4].

Most adolescents believe that e-cigarettes, regardless of their flavor, are less harmful than tobacco. However, around one in five adolescents were unsure whether e-cigarettes contain nicotine [7]. Till recently, there is still no solid evidence that e-cigarettes are safer than tobacco cigarettes or whether e-cigarettes help in smoking cessation [8]. Most adolescents declared that they became motivated to use e-cigarettes because of their peer influence. They also believed that e-cigarettes are less harmful than usual tobacco cigarette smoking. However, they also admitted that e-cigarette is not risk-free [9]. There are many risk factors associated with the increased susceptibility to use e-cigarettes among adolescents. Such factors include family influence, substance use, sensation seeking, transition to high school, and exposure to social media [10, 11].

As many adolescents perceive that e-cigarettes are safer than tobacco cigarettes and help in quitting smoking, their prevalence has increased. For example, a repeated cross-sectional online survey was conducted in the United States, Canada, and England between 2017 and 2019 to assess changes in the prevalence of using e-cigarettes among adolescents. Results of the survey revealed that the prevalence increased within all three countries (i.e., from 2.2% to 6.7% in the United States; 1.8% to 5.7% in Canada, and 1.5% to 2.7% in England) [12]. Furthermore, a cross-sectional study was conducted in Italy using the Global Youth Tobacco Survey (GYTS) among male and female adolescents aged between 13 and 15 years. The prevalence of tobacco smoking and e-cigarette smoking was estimated for the years of 2010, 2014, and 2018. The results showed that the prevalence of dual users increased from 20.7% in 2010 to 27.9% in 2018. While current smokers were around 20%, current e-cigarette smokers remarkably increased from 0% in 2010 to 7.4% in 2014, and further increased to 17.5% in 2018. In addition, the current exclusive e-cigarette smokers reported around a 3-fold significant increase from 2.9% in 2014 to 8.2% in 2018 [13].

In the same context but in the Arab world, a cross-sectional study was conducted in Saudi Arabia to assess the prevalence of e-cigarettes compared to tobacco cigarettes. A self-administered online questionnaire was distributed to 3000 students in different medical colleges at three different universities. A sample of 1007 students completed the electronic survey. The results revealed that 14.1% of the participants were tobacco cigarette users and 27.7% were e-cigarette users. Also, 42.7% of e-cigarette users used it as an alternative to quitting smoking [14]. In Jordan, a cross-sectional study targeted 1819 medical students to assess the prevalence and perceptions of e-cigarettes through a self-administered questionnaire. The results showed that most medical students (86%) were aware of the use of e-cigarettes and they reported that their use is less harmful and helpful in quitting smoking. Besides, 9.5% of all students (29% of all smoker students) were using e-cigarettes combined with another type of smoking [15].

In order to change the behavior of adolescents toward e-cigarettes, their level of knowledge and attitudes toward them should be assessed. For this purpose, a cross-sectional study was conducted in the USA among 69 adolescents aged between 14 and 18 years. The result showed that 47% of adolescents were ever-users of e-cigarettes. Compared to never-users, e-cigarette ever-users were significantly less likely to believe that e-cigarettes may lead to adverse health consequences and to believe that e-cigarette use may lead to addiction. Furthermore, participants who had smoked tobacco cigarettes ever were four times more likely to ever use e-cigarettes (p < 0.05) [16]. On the other hand, a series of focus group sessions with youths aged 12–17 years in Canada were formulated to assess their knowledge and perception toward e-cigarettes. The result revealed that most of the adolescents were willing to use e-cigarettes under their peer influence. They also perceived e-cigarettes as less harmful and easier to access and use than tobacco cigarettes [9].

In Jordan, the reported rates of e-cigarette smoking have noticeably increased [15]. Therefore, this study was conducted to assess the knowledge and attitudes of Jordanian adolescent students (15–19 years) toward e-cigarette smoking.

The study aims to answer the following research questions:

1. What are the levels of knowledge and attitudes of Jordanian adolescent students (15–19 years) toward e-cigarette smoking?

2. Is there a significant difference between Jordanian adolescent students who smoke (tobacco or e-cigarettes) and those who do not smoke regarding knowledge and attitude toward e-cigarettes?

Around 750 eligible students from the 10^th to 12^th class in the assigned governorates were available at the time of data collection. Around six hundred questionnaires were distributed. Five hundred questionnaires were returned for those who agreed to participate. There were no missing data as the online questionnaire was designed to reject the incomplete submission. There were no missing data as the Ages of the participants ranged between 15 and 19 years (mean = 16.76, SD = 1.17). Most of the participants were in governmental schools (n=440, 88%) and 12^th graders (n = 259; 51.8%). The level of education for mothers and fathers was reported to be more than high school by 45% of the students. Also, 56.6% of the students reported that the monthly income of their families was less than 500 Jordanian Dinar (JD) as shown in Table 1.

Regarding the smoking status of the participants, results revealed that 43% of the participants tried tobacco smoking and 35% tried e-cigarettes. Also, 14% of the participants were current tobacco smokers, while 7.6% were current e-cigarette users. Among those who smoked e-cigarettes, 4.0% used e-cigarettes for less than one year and 4.4% used e-cigarettes less than five times a day as shown in Table 2.

This study aimed to assess the knowledge of Jordanian adolescent students about e-cigarette smoking. The results revealed an adequate overall knowledge score about e-cigarettes. For example, over 95% of the study participants heard about e-cigarettes. The sources of e-cigarettes’ knowledge varied as well. This finding was congruent with the related research findings of Jordanian studies. Results of related studies in Jordan showed that 75% to 85% of college students heard and knew about e-cigarettes [15, 20]. In terms of sources of knowledge about e-cigarettes, studies carried out in different countries revealed that adolescents knew about e-cigarettes from friends and family [21, 22]. Social media and the internet were also influential in advertising e-cigarettes and it was evident in similar studies [19, 21, 22]. The feasibility of the internet and social media for adolescents in different cities and villages played an important role in advertising e-cigarettes in a way that may exceed the contribution of family and friends in this regard. Besides, social media and internet have unlimited boundaries in influencing adolescents’ knowledge and even attitudes because there are no rules governing the content that is shared and disseminated on these platforms.

In the current study, over 60% of the participants reported that they did not know about the various ingredients and chemicals or the different levels of nicotine present in e-cigarettes. These results are in correspondence with the studies carried out in Karachi and India, which revealed that 56% and 62% of adolescents were not aware of the composition of e-cigarettes, respectively [19, 23]. Lack of knowledge regarding the ingredients of e-cigarettes symbolizes the nature of adolescents who pay attention to the context rather than the core of issues. In other words, adolescents are taken by the behavior of e-cigarette smoking as they may feel mature and find their identity through smoking. In the meantime, they do not pay the least amount of attention to the core of that behavior in terms of identifying the ingredients of e-cigarettes and the subsequent risks associated with e-cigarette smoking. The influence of social media and advertising also fosters this point wherein adolescents may imitate idols they follow on social media without paying attention to the details behind those selected behaviors.

This study also aimed to assess the attitudes of Jordanian adolescent students toward e-cigarette smoking. The results revealed an overall positive attitudes score among the study participants. Over half of the participants agreed that using e-cigarettes is cleaner than tobacco smoking. In this regard, Gorukanti et al. (2017) indicated in their study in the USA that approximately 44% of participants believed that e-cigarettes are cleaner and safer than smoking cigarettes [24]. In addition, a study among some adults in Jordan showed that around one-third of the participants who were current e-cigarette users reported that it is a safer alternative to tobacco smoking [21]. Our study also showed that the majority of the participants (over 60%) agreed that raising taxes on e-cigarettes is a good idea and that they should be regulated by government agencies. If e-cigarettes are more expensive, they are less likely to be used by teenagers. This finding may represent a positive attitude for our participants. Their belief that raising taxes would be a good idea may reflect their intention to quit smoking, as raising prices and taxes would trigger it. Gorukanti et al. (2017) also found that almost 76% of adolescents believed raising e-cigarette and cigarette taxes was a good idea. Over 60% agreed that the age of buying e-cigarettes and cigarettes should be raised, and if they were more expensive, teenagers would be less likely to use them [24]. Based on the current and previous evidence, it is essential to involve government agencies to regulate the use of e-cigarettes, especially at work, schools, and public places, and raise taxes that may reduce the affordability of e-cigarettes among teenagers and young adults.

Our study results revealed that over 60% of the participants agreed that using e-cigarettes helps people to quit smoking tobacco cigarettes. Similarly, the results of previous studies in Saudi Arabia and Pakistan showed that over 40% of the participants used e-cigarettes as a method to quit tobacco smoking [14, 19]. Using e-cigarettes to quit smoking was justified by the findings of another cross-sectional study conducted among Jordanian medical students. Results of the study showed that smokers and non-smokers perceived e-cigarettes as less harmful than tobacco cigarettes and helpful in quitting smoking [15]. However, this finding should be stressed through smoking cessation interventions where proper and healthy ways to quit smoking are addressed in a scientific and logical way.

It was revealed in the current study that over 40% of the participants tried tobacco smoking and over 30% tried e-cigarettes. However, only 14% of the participants reported being current tobacco smokers and 7.6% reported being current e-cigarette users. Various prevalence rates of tobacco and e-cigarette smoking were revealed by participants of different studies. A study conducted in seven countries in Europe revealed that about 34% of adolescents had tried e-cigarettes and 37% had tried tobacco cigarettes. While 4% reported weekly use of e-cigarettes, 7% reported weekly tobacco smoking [25]. In contrast, a cross-sectional study among Saudi college students revealed that 14.1% were tobacco cigarette smokers, while 27.7% were e-cigarette users (Qanash et al., 2019). Also, a study in Jordan among medical students showed that around 10% of all the participants reported using e-cigarettes combined with another type of smoking [15]. The variation in prevalence rates of smoking in these studies might be due to the different cultures and socio-economic statuses in the different regions in addition to the differences between college and school students in terms of age and intellect.

This study aimed to identify differences in adolescents’ knowledge and attitudes based on their use and non-use of e-cigarettes. The results of our study showed that the students who reported using tobacco smoking and e-cigarettes had a significantly higher mean score of knowledge, but a lower mean score of attitudes compared to students who did not report using tobacco and e-cigarettes smoking. In this regard, a cross-sectional study in Pakistan among post-graduate medical trainees showed that there was a significant correlation between being a current smoker and possessing a higher amount of knowledge regarding e-cigarettes [26]. However, our results contradicted the ones found by Chudech and Janmaimool (2021) in Thailand wherein they found that the university students who were using e-cigarettes reported less knowledge, but a higher positive attitude toward e-cigarettes than those who were not using them. This contradiction might be due to the reason that university students are more mature than school students and have enough knowledge about the harmful effects of e-cigarettes. Thereafter, they are less likely to use e-cigarettes [27]. These results denote the importance of initiating health education for adolescents regarding all types of smoking early on in schools to enhance their knowledge and attitudes; a strategy that may reduce the chances of being a smoker during adulthood.

This study was among the first to assess the knowledge and attitude of adolescents in schools toward e-cigarettes. The results suggest that participants have an adequate overall level of knowledge and a positive attitude toward e-cigarettes. However, there is still a need for regular health promotion programs targeting school students. Nurses, teachers, health care providers, parents, and policymakers should work together to increase the awareness and knowledge of adolescents about the components of e-cigarettes, their harmful effects, addiction properties, and how to quit all types of smoking.