Nigerian Journal of Clinical Practice

ORIGINAL ARTICLE
Year
: 2022  |  Volume : 25  |  Issue : 7  |  Page : 979--986

Predictors of Shisha Use among Medical and Dental Students in Ibadan, Nigeria


OF Fagbule1, EO Cadmus2,  
1 Department of Periodontology and Community Dentistry, College of Medicine, University of Ibadan, and University College Hospital, Nigeria
2 Department of Community Medicine, College of Medicine, University of Ibadan, Nigeria

Correspondence Address:
Dr. O F Fagbule
Department of Periodontology and Community Dentistry, University College Hospital, Ibadan
Nigeria

Abstract

Background: Shisha is a form of smoked tobacco product. Medical trainees are potential stakeholders in providing accurate information about shisha and discouraging its use. However, few studies have targeted medical trainees to provide much-needed information for policymaking and planning of programs. Aim: To determine the prevalence and predictors of shisha use among medical and dental students in Ibadan, Nigeria. Subjects and Methods: A cross-sectional study was conducted among medical and dental students (n = 252) of the University of Ibadan, selected using the stratified random sampling technique. The Global Health Profession Students Survey (GHPSS) questionnaire was used to obtain information about socio-demographics, shisha and other tobacco use, and knowledge and attitude towards shisha use. The data were analyzed using Statistical Package for the Social Sciences (SPSS) version 25. Continuous data were presented using mean and standard deviation, whereas categorical variables were reported as proportions. The association between the outcome variable (shisha use) and independent variables (sociodemographic characteristics, having friends who use shisha) was measured using Pearson's Chi-square test, and factors significant (P < 0.05) were entered into the multivariable logistic regression model. Result: The mean age (± SD) was 21.7 (± 3.1) years. Over half [136 (54%)] were males, and most [199 (79%)] were medical students. About 28 (11%) were not aware of shisha, whereas 22 (8.7%) reported they had ever used shisha. The mean knowledge score was 5.6 ± 4.7, and 76 (33.9%) supported shisha use. Positive predictors of shisha use included the male gender [OR: 6.4 (95% CI: 1.76–23.10)] and having a friend who uses shisha [OR: 28.2 (95% CI: 5.49–144.23)]. Conclusion: The prevalence of shisha use among medical and dental students in Ibadan is unacceptably high, although low compared to other countries in similar resource settings. Surprisingly, the students had poor knowledge about shisha, and over a third supported its use, especially males who were more prone to use it. There is a need to design targeted health promotion and education for the students, especially males.



How to cite this article:
Fagbule O F, Cadmus E O. Predictors of Shisha Use among Medical and Dental Students in Ibadan, Nigeria.Niger J Clin Pract 2022;25:979-986


How to cite this URL:
Fagbule O F, Cadmus E O. Predictors of Shisha Use among Medical and Dental Students in Ibadan, Nigeria. Niger J Clin Pract [serial online] 2022 [cited 2022 Aug 8 ];25:979-986
Available from: https://www.njcponline.com/text.asp?2022/25/7/979/351468


Full Text



 Introduction



Shisha is a form of smoked tobacco, with similar constituents and health risks as other tobacco products. Shisha use has widespread acceptance and is quickly becoming a growing public health concern.[1],[2] Globally, over 100 million people use shisha daily, second only to cigarette smoking as the most common form of tobacco use.[3] Some of the reasons shisha use is fast gaining acceptance across the world include the erroneous belief of reduced harm,[4],[5],[6] peer pressure,[2] media influence, particularly advertisements and movies,[7] availability, affordability, and the unique innovation of the shisha smoking device.[7],[8]

Other factors include the supposed ability of shisha to alleviate social and academic stress,[9],[10],[11],[12],[13] pleasure-seeking,[14] boredom, and lack of shisha-specific policies and regulations.[13],[15] Of all the reasons, the notion that shisha is less harmful seems to be the most common reason responsible for its growing use.[16],[17],[18],[19] Shisha has also been reported to have better acceptance and use over cigarette smoking among medical students.[20] Medical and dental students undergo academic, emotional, and psychological stress[2],[21],[22] due to the broad curriculum and frequent examinations. Stress has also been a risk factor for shisha use among medical trainees.[23],[24],[25]

Medical professionals and trainees are expected to play critical roles in tobacco control. To do this effectively, they must know all forms of tobacco use and their effects. Also, students in the clinical space are expected to maintain a negative attitude towards the habit and be willing to offer tobacco cessation programs to their patients. However, research shows that tobacco use among health care professionals limits their interest in interventions with smokers and their involvement in tobacco control.[26]

Reports from studies conducted in other countries among medical personnel and trainees show that shisha use was high among doctors and dentists generally,[4],[27] especially interns, residents,[4] and medical students.[2],[16],[17],[20],[23],[28],[29] For instance, the reported prevalence of shisha use among health sciences students in Cape Town, South Africa, was 66% for ever-users, and 18% were current users.[29] However, recent reports have indicated an upsurge in shisha use in Nigeria. Very little is known about shisha's use among medical students in the country.[30],[31],[32] To effectively combat the upsurge of shisha use in Nigeria and prepare medical and dental trainees as stakeholders in tobacco control, it is essential to know their shisha use status and the associated factors.

Hence, this study aimed to assess the prevalence of shisha use among medical and dental students in Ibadan and determine the predictors of the habit thereof.

 Subjects and Methods



Study population

This study was conducted among medical and dental students in a tertiary institution in southwestern Nigeria. The study included all medical and dental undergraduate students from 200 level to 600 level. The ethical approval was obtained from the University of Ibadan and University College Hospital Ethical Review Committee on the 6th of February 2019 (UI/EC/18/0515).

The data were collected with the aid of a semi-structured self-administered questionnaire. The data were collected over 2 months from February 2019 to April 2019. Students in the preclinical classes (200 level and 300 level) are located on the main campus of the University of Ibadan (UI), whereas the clinical students (400 level – 600 level) reside and have their training in the University College Hospital (UCH), Ibadan. Both UI and UCH are in Ibadan, the capital city of Oyo State.

Study design

This was a cross-sectional study designed to assess the prevalence and predictors of shisha use among medical and dental students in Ibadan, Nigeria. A minimum sample size of 227 was initially calculated using the standard formula for the estimation of sample size for descriptive studies,[33] and using a reported prevalence of shisha use (18%) among health sciences students from Cape Town, South Africa.[29] However, after adjusting for a possible nonresponse rate of 10%, the sample size was adjusted to a minimum of 252 students.

Sampling method

A stratified random sampling technique was used to select the study participants. The study population was stratified based on their study (Medicine and Dentistry) and course level (200 L, 300 L, 400 L, 500 L, and 600 L). Proportional allocation was used to determine the number of students to be selected from each stratum. The sampling fractions for the different classes were 0.21, 0.22, 0.21, 0.20, and 0.15 for the 200 L, 300 L, 400 L, 500 L, and 600 L, respectively. The ratio of medical students to dental students was also maintained while selecting the study participants in all the class levels. According to level and course, a list of the students was obtained, and the study participants were subsequently selected using the computer-generated random number method.

Inclusion criteria: All 200 level to 600 level medical and dental students at the College of Medicine, University of Ibadan, were included in the study.

Exclusion criteria: Medical and dental students who were not in Ibadan during the period of data collection were excluded.

Study instrument

Self-administered, semi-structured questionnaires were used for this survey. The questionnaire was adapted from the Global Health Professional Students' Survey (GHPSS)[34] and a review of the literature.[17],[23],[35],[36] The questionnaire comprised the following sections, which measured: sociodemographic characteristics, shisha and other tobacco use, and knowledge and attitude towards shisha use.

Study measures

The prevalence of shisha use was assessed using a “Yes” or “No” response to the question “Have you ever tried or experimented with shisha, even one or two puffs?”. Likewise, the prevalence of tobacco use was determined based on the response to the question, “Have you ever tried or experimented with cigarette smoking, even one or two puffs?” Current cigarette smoking was assessed with the question ”During the past 30 days (one month), on how many days did you smoke a cigarette?” Respondents that indicated 1 or more days were grouped as current cigarette smokers. Also, their use of other tobacco products was assessed with the question, “Have you ever used other tobacco products other than cigarettes?” The respondents' awareness of shisha was assessed by asking if they have heard or seen shisha before. Those who chose “no” were categorized as “unaware.” Respondents unaware of shisha use were not asked further questions about their knowledge and attitude towards shisha use. Questions assessing participants' knowledge of shisha were broadly under three main domains: knowledge about shisha content (seven items), knowledge of the health effects of shisha smoking (eight items), and two other questions on knowledge about the regulation of shisha in Nigeria. The options were “Yes,” “No,” and “I don't know.” The correct answers were given a score of 1, whereas incorrect answers and “I don't know” were awarded a 0 score. A total knowledge score was created, which is the sum of all the questions, thus giving 17. Using the mean knowledge score as the benchmark, the respondents were subsequently divided into two groups – “good knowledge” vs “poor knowledge.”

Attitude towards shisha was assessed using 18 questions, and the responses were on Likert scale (Strongly agree, agree, neither agree nor disagree, disagree, and strongly disagree). “Strongly agree” and “agree” were grouped as “agreed,” whereas “disagree” and “strongly disagree” were grouped as “disagreed” and “neither agree nor disagree” as “unsure.” Based on the responses, those who chose positive responses were given a score of 1, whereas 0 was given for negative responses. The mean score was then used to categorize the respondents into having a positive or negative attitude.

Socio-demographic variables included age, gender (male, female), marital status (single, married), course stage (preclinical and clinical), and course of study (medicine and dentistry).

Statistical analysis

The data were analyzed using the Statistical Package for the Social Sciences (SPSS) version 25.0. Descriptive statistics were performed using frequencies and proportions, mean scores, and standard deviation computed. Factors associated with shisha use were measured using Pearson's Chi-square test at a level of significance set at P < 0.05. Furthermore, multivariable logistic regression modeling was performed using variables that were independently associated at P < 0.10 with ever-shisha use.

Ethical considerations

Ethical approval was obtained from the University of Ibadan and University College Hospital (UI/UCH) Ethics Review Committee (UI/EC/18/0515), and permission was obtained from the Provost's office. In addition, written informed consent was obtained from the respondents. The anonymity of the study respondents, as well as the confidentiality of the data, was maintained.

 Results



Two hundred and sixty-seven eligible participants were approached, and 255 responded, giving a response rate of 95.5%. However, three of the questionnaires were not filled appropriately, with a significant number of missing responses. These were removed, leaving a total of 252 participants whose data were analyzed.

Socio-demographic characteristics of the respondents

The mean age (± SD) of the respondents was 21.7 (± 3.1) years. About two-thirds (69.4%) of the respondents were aged between 20 and 24 years old, over half were males (54%), and over three-quarters (79%) were studying medicine [Table 1].{Table 1}

Knowledge attitude and awareness of shisha

A total of 224 (88.9%) respondents had heard (aware) of shisha, and the three most common sources of information were via the television (52.7%), friends (42.4%), and radio (30.8%) [Figure 1].{Figure 1}

[Table 2] shows that among the 224 respondents who had heard about shisha, the mean (± SD) knowledge score was 5.6 (± 4.65) out of 17. Overall, 58.0% of the study participants had below the mean score for this population and categorized as having poor knowledge about shisha contents and effects. Less than half (42.9%) of the respondents knew that shisha contains tobacco, and only 32.7% knew that shisha use is linked to cancer. The majority (85.3%) of the respondents either disagreed or were unsure that the liquid in shisha could be replaced with alcohol.{Table 2}

[Table 3] shows that, overall, one out of every three students supported the use of shisha. About one-quarter did not believe that shisha use is bad, and it is not good for their health. Less than half of the respondents disagreed that “shisha use is safe because the smoke is filtered through water.” Generally, over 80% of the students thought that health professionals should routinely advise people to avoid using shisha and acquire shisha-specific cessation training. Over half (51.8%) of the respondents believed that shisha use is more socially acceptable than cigarettes, and the majority (71.0%) of the respondents believed that shisha is preferred over a cigarette as a form of tobacco use. Three-quarters (75.9%) believed shisha should not be sold to adolescents, 63.4% wanted a complete ban on advertisement, and 79.9% wanted the same laws applied to cigarette smoking and shisha use.{Table 3}

Shisha use

Twenty-two (8.7%) respondents had used shisha, out of which 15 (63.6%) were initiated by their friends. Most of the respondents, [19 (70.4%)]usually smoked in the club [Figure 2]. Sixty-nine (31.4%) and 17 (7.7%) respondents had a close friend and family member, respectively, who used shisha [Table 4].{Figure 2}{Table 4}

Factors associated with shisha use

[Table 5] shows that a higher proportion of males [18 (13.2%)] reported shisha use compared to females [4 (3.4%)], and this difference in proportions was statistically significant (P < 0.05). Likewise, a higher proportion of respondents who had friends [20 (29.0%)] and families [6 (35.3%)] who used shisha reported shisha use (P < 0.05). A statistically significantly higher proportion of respondents who had smoked cigarettes [15 (71.4%)] reported shisha use compared to nonsmokers [7 (3.0%)] (P < 0.05). Following multivariate logistic regression analysis, factors predictive of shisha use among the respondents were being a male [OR: 6.4 (95%CI: 1.76-–23.10)] and having a friend who smokedshisha [OR: 28.2 (95%CI: 5.49–144.23)] [Table 6].{Table 5}{Table 6}

 Discussion



This study found that awareness of shisha use and knowledge about its contents and health effects was suboptimal. The proportion of the students who had used shisha is relatively low compared to the report from similar studies done in other parts of the world – South Africa with 66.0%,[29] Canada with 39.9%,[17] Pakistan with 22.8%,[28] 19.3%,[16] and 14%.[2] A possible reason for this lower prevalence is that tobacco use is generally relatively lower in Nigeria compared to some other low- and middle-income countries (LMICs).[37] Interestingly, the respondents who had smoked cigarettes were more likely to report shisha use than noncigarette smokers. This affirms studies that have shown an association between cigarette smoking and other forms of tobacco, such as shisha.[38]

Also, unlike the males, a higher percentage of females had attempted using shisha compared to cigarettes. This corroborates findings from other studies that a higher proportion of females than males prefer shisha use over cigarette smoking.[16],[20],[28],[39],[40] Likewise, the age of first shisha use ranged from 15 to 25 years old, similar to a study in Pakistan with 18–24 years.[16] This finding implies that, on average, uptake of shisha use among this population is more of a recent occurrence, as their mean age was 21.7 (± 3.1) years. This is understandable considering that shisha use is also new in the country.

Similar to previous research, predictors of shisha use were the male gender[16],[20],[28],[41] and having friends who use shisha.[28],[42] Thus, these must be considered when planning tobacco control interventions among this group.

Overall, the level of knowledge of the study participants was very low. This is of concern because medical and dental students often serve as a source of health information to other students in the university. Considering that shisha use is quite new in Nigeria with numerous conflicting information about its health effects, medical and dental students are in an excellent position to provide the needed clarifications on these and other shisha-related questions to their peers. Hence, they should have adequate knowledge about it themselves.

The attitude towards a particular behavior is a strong indication of the likelihood of engaging or rejecting such behavior.[42],[43] Considering that shisha smoking is an unhealthy habit with associated health consequences, it would be expected that those who would play key roles in this regard should have an attitude that rejects shisha use and supports its regulation. This study, however, showed that one out of every three medical and dental students supported shisha use, and one in every four believed that shisha use is safe. The result from this study is also in tandem with the notion that compared to cigarette smoking, shisha use is more accepted among females,[44] with the majority (51.8%) in this study agreeing with the statement in the questionnaire that females are more comfortable to use shisha compared to cigarettes.

This study is not without its limitations being a cross-sectional study design, causality cannot be inferred. However, as we did not set out to find out causality but associated factors, we do not think this is a problem. Furthermore, the information provided was self-reported and prone to under-reporting, especially among those who may be engaged in the habit of smoking and who do not want others to know about it. In a bid to minimize possible under-reporting, the respondents were assured that their responses were anonymous and cannot be traced back to them. Lastly, some of the information requested was about events that may have occurred in the past and is prone to recall bias. Although considering that initiating shisha use would be a unique experience to any of the respondents, it is not likely that they would have any problem recalling such an event.

 Conclusion



The prevalence of shisha use among medical and dental students in Ibadan is relatively low compared to other LMICs. However, their knowledge about shisha was sub-optimal, and a third of the students supported shisha use. There is a need to educate the students about shisha use. The result of the study will contribute to the development of tobacco (shisha) control measures, stimulate further research, and increase the consciousness of the participants as well as other medical and dental students about shisha and its health effects.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form, the patients have given their consent for their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References

1Maziak W, Ward KD, Afifi Soweid RA, Eissenberg T. Tobacco smoking using a waterpipe: A re-emerging strain in a global epidemic. Tob Control 2004;13:327-33.
2Kumar A, Baig S, Ansari S, Rizvi N, Sharif H, Beg AE, et al. Comparison of Shisha smoking behavior among medical and pharmacy students. J Behav Brain Sci 2016;6:269–79.
3Ward KD, Hammal F, VanderWeg MW, Eissenberg T, Asfar T, Rastam S, et al. Are waterpipe users interested in quitting? Nicotine Tob Res 2005;7:149–56.
4Kumar A, Ghazal S, Malik M, Rizvi N, Ismail S. Knowledge attitudes and practices of shisha smoking among medical practitioners in Karachi, Pakistan. J Smok Cessat 2013;10:44–9.
5Jawaid A, Zafar AM, Rehman TU, Nazir MR, Ghafoor ZA, Afzal O, et al. Knowledge, attitudes and practice of university students regarding waterpipe smoking in Pakistan. Int J Tuberc Lung Dis 2008;12:1077–84.
6Morton J, Song Y, Fouad H, El Awa F, El Naga RA, Zhao L, et al. Cross-country comparison of waterpipe use: Nationally representative data from 13 low and middle-income countries from the Global Adult Tobacco Survey (GATS). Tob Control 2014;23:419–27.
7Nakkash RT, Khalil J, Afifi RA. The rise in narghile (shisha, hookah) waterpipe tobacco smoking: A qualitative study of perceptions of smokers and non smokers. BMC Public Health 2011;11:315.
8Akl EA, Jawad M, Lam WY, Co CN, Obeid R, Irani J. Motives, beliefs and attitudes towards waterpipe tobacco smoking: A systematic review. Harm Reduct J 2013;10:12.
9Fevrier B, Nabors L, Vidourek RA, King KA. Hookah use among college students: Recent use, knowledge of health risks, attitude and reasons for use. J Community Health 2018;43:1037-43.
10Asfar T, Ward KD, Eissenberg T, Maziak W. Comparison of patterns of use, beliefs, and attitudes related to waterpipe between beginning and established smokers. BMC Public Health 2005;5:19.
11Momenabadi V, Hossein Kaveh PhD M, Hashemi SY, Borhaninejad VR. Factors affecting hookah smoking trend in the society: A review article. Addict Health 2016;8:123–35.
12Jallow IK, Britton J, Langley T. Prevalence and determinants of tobacco use among young people in the Gambia. BMJ Glob Health 2017;2:e000482. doi: 10.1136/bmjgh-2017-000482.
13Faseru B, Barengo NC, Sandström HP, Omokhodion F. Smoking behavior and perception of risk among medical students in Ibadan, Nigeria. Prev Control 2006;2:103–9.
14Mohammed FA, Kanmodi KK, Fagbule OF, Adesina MA, Njideka NJ, Sadiq HA. Shisha smokers' desire to quit shisha smoking habit: Findings from a Nigerian pilot survey. Glob Psychiatry 2019;2:37-41.
15Maziak W, Taleb ZB, Bahelah R, Islam F, Jaber R, Auf R, et al. The global epidemiology of waterpipe smoking. Tob Control 2015;24:i3–12. doi: 10.1136/tobaccocontrol-2014-051903.
16Haroon M, Munir A, Mahmud W, Hyder O. Knowledge, attitude, and practice of water-pipe smoking among medical students in Rawalpindi, Pakistan. J Pak Med Assoc 2014;64:155–8.
17Vanderhoek AJ, Hammal F, Chappell A, Wild TC, Raupach T, Finegan BA. Future physicians and tobacco: An online survey of the habits, beliefs and knowledge base of medical students at a Canadian University. Tob Induc Dis 2013;11:1–9.
18Sutfin EL, McCoy TP, Reboussin BA, Wagoner KG, Spangler J, Wolfson M. Prevalence and correlates of waterpipe tobacco smoking by college students in North Carolina. Drug Alcohol Depend 2011;115:131–6.
19Kanmodi KK, Mohammed FA, Nwafor NJ, Fagbule OF, Adesina MA, Aliyu BM, et al. Poor knowledge of the harmful effects of Shisha among shisha smokers: Findings from a preliminary survey in Northwest Nigeria. Med Univ 2019;2:49–56.
20Almerie MQ, Matar HE, Salam M, Morad A, Abdulaal M, Koudsi A, et al. Cigarettes and waterpipe smoking among medical students in Syria: A cross-sectional study. Int J Tuberc Lung Dis 2008;12:1085–91.
21Al-Bitar ZB, Sonbol HN, Al-Omari IK. Reasons for choosing dentistry as a career by Arab dental students. Eur J Dent Educ 2008;12:247–51.
22Waqas A, Khan S, Sharif W, Khalid U, Ali A. Association of academic stress with sleeping difficulties in medical students of a Pakistani medical school: A cross sectional survey. PeerJ 2015;3:e840. doi: 10.7717/peerj. 840.
23Al-naggar RA, Bobryshev YV. Shisha smoking and associated factors among medical students in Malaysia. Asian Pacific J Cancer Prev 2012;13:5627–32.
24Kumar A, Mahmud M, Hussain N, Nabi Z, Shah B, Rizvi N. Knowledge and behaviour of physicians and surgeons regarding Shisha smoking. Br J Med Med Res 2016;13:1–12.
25Shah M, Hasan S, Malik S, Sreeramareddy CT. Perceived stress, sources and severity of stress among medical undergraduates in a Pakistani medical school. BMC Med Educ 2010;10:2.
26Sarna L, Bialous SA, Sinha K, Yang Q, Wewers ME. Are health care providers still smoking? Data from the 2003 and 2006/2007 tobacco use supplement-current population surveys. Nicotine Tob Res 2010;12:1167–71.
27Abdulateef DS, Ali AJ, Abdulateef DS, Mohesh MIG. Smoking knowledge, attitude, and practices among health care professionals from Sulaymaniyah City/Iraq. Tob Use Insights 2016;9:1–6.
28Khan N, Ahmed SM, Khalid MM, Siddiqui SH, Merchant AA. Effect of gender and age on the knowledge, attitude and practice regarding hepatitis B and C and vaccination status of hepatitis B among medical students of Karachi, Pakistan. J Pak Med Assoc 2010;60:107–12.
29van der Merwe N, Banoobhai T, Gqweta A, Gwala A, Masiea T, Misra M, et al. Hookah pipe smoking among health sciences students. South African Med J 2013;103:847–9.
30Alabi CT, Bulama M. The emergence of Shisha in Kaduna. Daily Trust [Internet]. Available from: https://www.dailytrust.com.ng/sunday/index.php/feature/14407-the-emergence-of-shisha-in-kaduna [Last accessed on 2013 Sep 22].
31Ololade O. The Shisha Pandemic. The Nation, Nigeria [Internet]. 2017. Available from: http://thenationonlineng.net/the-shisha-pandemic/ [Last accessed on 2018 Apr 02].
32Abraham EA, Egbe CO, Ayo-Yusuf OA. News media coverage of shisha in Nigeria from 2014 to 2018. Tob Induc Dis. 2019;17:33. doi:10.18332/tid/106139.
33Kish L. Survey Sampling. New York, NY John Wiley sons. 1965;78-94.
34WHO, CDC. Global Health Professionals Survey (GHPS). World Health Organization; 2006. p. 1-8.
35Maziak W, Ward KD, Afifi Soweid RA, Eissenberg T. Standardizing questionnaire items for the assessment of waterpipe tobacco use in epidemiological studies. Public Health. 2005;119:400-4.
36Ehizele A, Ojehanon P, Umoh A, Azodo C, Akhionbare O, Adeghe H. Prevalence of tobacco use among dental patients and their knowledge of its health effects. Niger J Clin Pract. 2012;15:270-5. doi:10.4103/1119-3077.100619.
37Mamudu H, Malau M, Osaghae I, Erameh A, Okeke A, Buhari O. Africa Tobacco Industry Monitoring (ATIM) Country Report: Nigeria. Ayo-Yusuf O, Chirawu P, editors. Pretoria; 2020.
38Majeed BA, Sterling KL, Weaver SR, Pechacek TF, Eriksen MP. Prevalence and harm perceptions of hookah smoking among U.S. adults, 2014–2015. Addict Behav. 2017;69:78-86.
39Khalaf Abed H. Shisha Habit among Medical Students at College of Medicine and College of Dentistry-Baghdad University. J Heal Educ Res Dev [Internet]. 2017;05. doi:10.4172/2380-5439.1000239.
40Samet JM, Yoon S-Y. Gender, Women, and the Tobacco Epidemic. Geneva: World Health Organization; 2010.1-253.
41Shuja S, Hussain A, Malik S, Rizwan T, Amin M, Choudhry Z. Perceptions Of Health Professional Students Regarding Waterpipe Smoking And Its Effects On Oral Health. J Ayub Med Coll Abbottabad. 2018;30:90-3.
42Omotehinwa OJ, Japheths O, Damascene IJ, Habtu M. Shisha use among students in a private university in Kigali city, Rwanda: prevalence and associated factors. BMC Public Health. 2018;18:713. doi:10.1186/s12889-018-5596-1.
43Aryal UR, Petzold M, Krettek A. Perceived risks and benefits of cigarette smoking among Nepalese adolescents: a population-based cross-sectional study. BMC Public Health. 2013;13:187. doi:10.1186/1471-2458-13-187
44Maziak W, Rastam S, Eissenberg T, Asfar T, Hammal F, Bachir ME, et al. Gender and smoking status-based analysis of views regarding waterpipe and cigarette smoking in Aleppo, Syria. Prev Med (Baltim). 2004;38:479-84.