the changing socio - demographic and epidemiological transition in developing countries has brought non - communicable diseases ( ncds ) to the forefront of health care delivery system . research in the past two decades has shown a number of risk factors operating in multiple ways to be major contributing factors for the emergence of ncds . tobacco use is widely recognized as the single most preventable cause of premature death due to these ncds . the role of smoking in the development of lung cancer , chronic obstructive pulmonary disease , and cardiovascular diseases has been established since the middle of the last century . world health organization estimates that nearly 5.4 million deaths can be attributed to tobacco usage every year . furthermore , nearly three - fourths of these deaths will be occurring in low- and middle - income countries of the world . thus , tobacco use has become one of the major challenges to public health today . tobacco use is typically woven into everyday life , and can be physiologically , psychologically , and socially reinforcing . many factors , including media depictions and cultural and societal acceptance of tobacco use , combined with tobacco 's addictive capacity , are making tobacco usage more prevalent . children in schools are in a period of transition between adolescence and adulthood , where behavior is influenced by accelerated changes affecting biological , emotional , cognitive , and social functions . unhealthy behaviors developed at this stage may be malleable or consolidated into lifetime patterns . moreover , adolescents and young adults of colleges and schools are often targeted by the tobacco industry for marketing . the risk factors for initiation of smoking in young adults or adolescents are as follows : 
 low socioeconomic statussmoking by parents or guardians and/or lack of parental support or involvementuse and approval of tobacco by peers and siblingsa perception that tobacco use is the normlow academic achievementlow self - esteem or self - imagelack of skills to resist influences promoting tobacco useexposure to smoking in moviesaccessibility , availability , and costaggressive behavior . low socioeconomic status smoking by parents or guardians and/or lack of parental support or involvement use and approval of tobacco by peers and siblings a perception that tobacco use is the norm low academic achievement low self - esteem or self - image lack of skills to resist influences promoting tobacco use exposure to smoking in movies accessibility , availability , and cost tobacco behavior among youth is an extremely complex area in india . use of smokeless tobacco , like gutkha ( an inexpensive chewing tobacco ) , is most popular among youth , followed by cigarette and bidi smoking ( a hand - rolled , filter - less cigarette ) . therefore , the present study was conducted to assess the knowledge , attitude , and behavior determinants of tobacco usage among high school students ( 1315 years ) in bangalore . the present cross - sectional study was conducted in bangalore over a period of 3 weeks in the month of september 2012 . bangalore is the third most populous city in india and the 18 most populous city in the world . the population of bangalore was estimated to be 9,621,551 in 2011 . the educational authority in bangalore the present study area belongs to bangalore north , which comprises both the urban and peri - urban population . in yelahanka , a total of 159 schools are present , from which 12 schools were selected using simple random technique . the study population comprised high school students aged 1315 years ( 8 , 9 , and 10 standard ) from yelahanka , bangalore . a pilot study was conducted on a sample of 100 school - going children selected from one high school . this was done to determine the feasibility of the study , the applicability and accuracy of the questionnaire , and to determine the amount of time required for interview . the sample size determination was carried out using the formula , where z = 95% confidence interval ( ci ) = 1.96 e = 4.5% = 0.045 ( standard error ) after conducting the pilot study , the confidence interval ( ci ) was set at 95% with a margin error of 4.5% . on the basis of the pilot survey , the sample size was fixed at 500 . the ethical clearance was obtained from the institutional review board ( irb ) of krishnadevaraya college of dental sciences and hospital , bangalore . the required official permission to select and collect the relevant data from selected subjects was solicited and obtained from the principals of the respective schools . informed consent was obtained from parents / guardians of subjects after explaining the purpose of the study . the study subjects were interviewed using a structured , pretested , close- and open - ended questionnaire . the participants were interviewed about their experience with tobacco smoking and environmental exposure to tobacco , perception of tobacco smoking , exposure to tobacco advertising in the media , whether they were taught in school about the harmful effects of tobacco use and smoking , attempts to stop smoking , and attitudes toward cessation of smoking . considering the sensitivity of the topic , the school authorities were requested not to be present in the class during the procedure of filling the questionnaire . interviews were scheduled during the working hours of the school to ensure the presence of the children . on an average , 2030 subjects were interviewed each day . the data were entered into the computer ( microsoft office , excel ) and were subjected to statistical analysis using the statistical package spss version 13 . preliminary descriptive analysis was used to assess the distribution of responses of all the study variables , and the association between dependent and explanatory variables was assessed using  test ( chi - square test ) . the data were entered into the computer ( microsoft office , excel ) and were subjected to statistical analysis using the statistical package spss version 13 . preliminary descriptive analysis was used to assess the distribution of responses of all the study variables , and the association between dependent and explanatory variables was assessed using  test ( chi - square test ) . the study population consisted of a total of 500 school - going children of whom 151 ( 30.2% ) , 182 ( 36.4% ) , and 167 ( 33.4% ) were aged 13 , 14 , and 15 years , respectively . among them , 281 ( 56.2% ) were males and 219 ( 43.8% ) were females . majority of the study population [ 94.4% ( 472 ) ] believed that smoking is definitely harmful to our health , of which 30.51% ( 144 ) , 36.02% ( 170 ) , and 33.47% ( 158 ) were 13 , 14 , and 15 year olds , respectively . very less number of participants [ 4.2% ( 21 ) ] believed that smoking is not harmful to health . almost in 60.8% ( 304 ) of the study population , family members have discussed about the harmful effects of smoking . a large percentage of the study population ( 46.4% ) thought that smoking does not help either in gaining or losing weight . however , an equal percentage of ( 44% ) of the study participants believed that smoking helps in losing weight . 90.8% ( 454 ) of the study population agreed that passive smoking is injurious to health ; very less number of participants thought it will not have any harmful effect ( 2.4% ) . sixty - one percent ( 305 ) of the students reported having been taught in school about the harmful effects of smoking , whereas 39% were not taught about the harmful effects of smoking . also , 67% of the participants informed that they had no chapter on the ill effects of smoking in their syllabus [ table 1 ] . smoking - related knowledge among different age groups when the study participants were asked about their attitude toward starting the smoking habit , most of them had negative attitude ( 96.6% ) . almost 82.8% ( 414 ) of the study population had displayed strong attitude toward banning smoking at all the public places , compared to 10.4% of the participants who were not in favor of banning smoking in public places . over 40.2% ( 201 ) of the study participants were of the opinion that smoking does not help in social acceptance into friend circle , and most of them ( 36.82% ) were aged 14 years , whereas , 20.8% of the population believed that smoking helps in social acceptance into friend circle . also , 96.8% of the study population , which was predominated by 14 year olds ( 35.95% ) , was not ready to accept cigarette from their best friend . among the study population , 83.8% ( 419 ) thought a man who smokes lacks confidence and only 10.4% thought a man who smokes is cool . similarly , 82.2% participants thought a woman who smokes lacks confidence and only 11.8% of the population thought a woman who smokes is cool [ table 2 ] . smoking - related attitude among different age groups out of the total study population , only 0.3% ( 15 ) participants were smokers . when asked about quitting the smoking habit , 14 year olds showed more interest as compared to others , but their efforts to quit the habit were very less . the smokers received more information about quitting the habit from doctors [ table 3 ] . this study comprehensively assesses the knowledge , attitude , and behavioral determinants of tobacco use among the high school students of yelahanka , bangalore . adolescence is a critical time in one 's life , and the habits and behavior formed during these years can have a long - lasting impact on the health of the individual . the knowledge , attitude , and behavioral determinants of tobacco use among the youth are important both to assess tobacco as a risk factor and to establish control measures for prevention of these diseases . results revealed 94.4% of the study subjects had knowledge about the harmful effects of smoking . showed a comparatively lesser knowledge of harmful effects of smoking of 84.6% , 71% , 84.5% , 72.3% , and 71.7% , respectively . this conflict of results could be due to a greater consciousness of the health consequences of addiction among the study participants . about 40.2% of the study participants thought that smoking does not help in socializing , which is almost similar to the findings of saji et al . in contrast , the study by mpabulungi et al . showed that smokers had more friends than those who did not smoke ( 35.6% ) . most of the study participants had negative perceptions about smokers , which was that they lacked confidence . their negative attitude toward smoking might be due to observance of local customs in which smoking is not considered an acceptable behavior . about 46.4% of the study subjects thought that smoking does not help in gaining or losing weight . in contrast , the study conducted by mpabulungi et al . reported that 67.4% of the study participants thought that smoking makes one lose weight . this finding suggests that an approach that increases knowledge is needed with particular emphasis on the short- and long - term effects of smoking . about 90.8% ( 454 ) of the study population agreed that passive smoking is injurious to health . around 82.8% supported ban on smoking in public places ( such as hotels , taxis , schools , markets , and playgrounds ) . a large percentage reported being taught about the ill effects of smoking in school ( 61.0% ) and by family members ( 60.8% ) . therefore , family and school teachers are primarily responsible for imparting knowledge regarding smoking , and these findings are similar to those of a study conducted by tsering et al . a majority of the users reported that they had not tried to stop smoking , which is in accordance with the report of multani et al . in contrast , studies by tsering et al . , fida et al . , and mpabulungi et al therefore , motivation on the part of family , friends , and close ones could help them to come out of this . there is a need to follow - up this age group to determine the trends of tobacco use , in order to adjust targeted tobacco prevention strategies . in contrast , the study conducted by mpabulungi et al . reported that higher percentage of cigarette users ( 77.9% ) expressed their desire to quit the habit . however , a study by gopikrishna et al . reported a lesser percentage ( 34% ) of the study participants expressing their desire to quit smoking . firstly , the findings of the present study can not be generalized to the entire population , as it is conducted on a small sample . secondly , the surveys usually do not reveal the real behavior of the respondents , as people tend to answer more according to the social norm than according to the actual situation , i.e. social desirability bias . lastly , as with any cross - sectional data , causality can not be inferred from the observed associations in the current study . they had a negative attitude toward smoking . however , less than 1% of the study population had the habit of cigarette smoking at this young age . the study provides useful insights into the factors to be considered in planning adolescent anti - smoking programs in this and similar settings . school - based awareness programs followed by cessation initiatives utilizing peer pressure should be carried out , so that the students can resist pressure to tobacco use . such smoking prevention programs may focus on modifying the attitudes toward smoking and providing a cigarette - free environment in and around the school campus .
background : the epidemic of tobacco use is one of the greatest threats to global health today . 
 tobacco attributable deaths in india currently range from 800,000 to 900,000 per year . 
 adolescents are among the most vulnerable group to start tobacco use . 
 information on tobacco use among the youth is necessary to establish control measures against it.objectives:to assess the knowledge , attitude , and behavioral determinants of tobacco use among high school students ( age1315 years ) in bangalore.materials and method : a cross - sectional study was conducted over a period of 3 weeks in the month of september 2012 . 
 a structured , pretested questionnaire was administered randomly to 500 high school students in bangalore to assess the knowledge , attitude , and behavioral determinants of tobacco use.results:majority of the study population [ 94.4% ( 472/500 ) ] believed that smoking is definitely harmful to our health . 
 also , 39.0% of the participants of age 13 years believed that smoking does not help in socializing and 92.2% of study subjects had negative attitude toward starting the habit . 
 most of them ( 83.9% ) had a negative perception about smokers that they lack confidence 
 . however , less than 1% of the study population had a habit of smoking at this young age.conclusion:awareness of the harmful effects of smoking was high among the study population . 
 the study provides insight into the factors to consider while planning adolescent anti - smoking programs in this and similar settings .