***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Among adolescents who experimented with cigarettes , trying e-cigarettes was associated with 1.8 times higher odds of progression to established cigarette smoking in a national prospect i ve cohort . BACKGROUND : It has been shown that never-smoking adolescents who try electronic cigarettes ( e-cigarettes )  are at increased risk of subsequent conventional cigarette smoking . We evaluated associations between e-cigarette use and progression to established smoking among adolescents who had already tried cigarettes . METHODS : Among participants ( age 12–17 years ) in the nationally representative Population Assessment of Tobacco and Health survey who had smoked a cigarette ( ≥1 puff ) but not yet smoked 100 cigarettes ( N = 1295 ) , we examined 3 outcomes at 1-year follow-up as a function of baseline e-cigarette use : ( 1 ) having smoked ≥100 cigarettes ( established smoking ) , ( 2 ) smoking during the past 30 days , and ( 3 ) both having smoked ≥100 cigarettes and past 30-day smoking ( current established smoking ) . Survey-weighted multivariable logistic regression models were fitted to obtain odds ratios ( ORs ) and 95 % confidence intervals ( CIs ) adjusted for smoking risk factors . RESULTS : Versus e-cigarette never use , having ever used e-cigarettes was positively associated with progression to established cigarette smoking ( 19.3 % vs 9.7 % ) , past 30-day smoking ( 38.8 % vs 26.6 % ) , and current established smoking ( 15.6 % vs 7.1 % ) . In adjusted models , e-cigarette ever use positively predicted current established smoking ( OR : 1.80 ; 95 % CI : 1.04–3.12 ) but did not reach statistical significance ( α = .05 ) for established smoking ( OR : 1.57 ; 95 % CI : 0.99–2.49 ) and past 30-day smoking ( OR : 1.32 ; 95 % CI : 0.99–1.76 ) . CONCLUSIONS : Among adolescent cigarette experimenters , using e-cigarettes was positively and independently associated with progression to current established smoking , suggesting that e-cigarettes do not divert from , and may encourage , cigarette smoking in this population UNLABELLED RATIONALE , AIMS & OBJECTIVE : Tools for the assessment of the quality of research studies tend to be specific to a particular research design ( e.g. r and omized controlled trials , or qualitative interviews ) . This makes it difficult to assess the quality of a body of research that addresses the same or a similar research question but using different approaches . The aim of this paper is to describe the development and preliminary evaluation of a  quality assessment tool that can be applied to a method ologically diverse set of research articles . METHODS The  16-item quality assessment tool ( QATSDD )  was assessed to determine its reliability and validity when used by health services research ers in the disciplines of psychology , sociology and nursing . Qualitative feedback was also gathered from mixed- methods health research ers regarding the comprehension , content , perceived value and usability of the tool . RESULTS Reference to existing widely used quality assessment tools and experts in systematic review confirmed that the components of the tool represented the construct of ' good research technique ' being assessed . Face validity was subsequently established through feedback from a sample of nine health research ers .  Inter-rater reliability was established through substantial agreement between three review ers when applying the tool to a set of three research papers ( κ = 71.5 % ) , and good to substantial agreement between their scores at time 1 and after a 6-week interval at time 2 confirmed test-retest reliability . CONCLUSIONS The QATSDD shows good reliability and validity for use in the quality assessment of a diversity of studies , and may be an extremely useful tool for review ers to st and ardize and increase the rigour of their assessment s in review s of the published papers which include qualitative and quantitative work Objectives : The objectives of this study were to assess the general public views and familiarity toward  electronic cigarette ( e-cigarette )  in Kuantan , Malaysia . Methodology : A total of 277 Kuantan people were involved in this study . The question naire was distributed at r and om in shops , businesses , and public places in Kuantan . Statistical analysis was performed using SPSS ( version 17.0 ) . Results : From 400 participants , a total number of 277 ( 160 , 57.7 % men and 117 , 42.4 % women ) respondents completed the question naire . The mean age was 26.89 ± 9.8 years old . The majority of the study participants were male ( 57.7 % ) , Malay ( 83.8 % ) , Muslims ( 83.8 % ) , singles ( 69 % ) , and employed ( 75.8 % ) , with about 83 ( 29.9 % ) of the respondents were smokers . The prevalence of e-cigarettes smokers was found to be only 1.4 % ( n = 4 ) . About one-third of the respondents ( n = 72 , 26 % ) have tried e-cigarette before . Job status was significantly associated with smoking e-cigarette among the population ( P = 0.02 ) . Main factors for a person to start e-cigarette smoking were curiosity ( 37.5 % ) and cheaper price ( 40.8 % ) . Majority of respondents agreed that e-cigarette would not affect health as normal cigarette , and that variety of flavors contribute to better enjoyment ( 51.6 % and 66.7 % , respectively ) . Conclusion : The results of the current study demonstrate that the prevalence of e-cigarettes smoking and its popularity , familiarity , and knowledge are still insufficient among Kuantan population . Further studies should be done to tackle this problem before it getting worse Objective E-cigarette use has rapidly increased . Recent studies define prevalence using a variety of measures ; competing definitions challenge cross- study comparison . We sought to underst and patterns of use by investigating the number of days out of the past 30 days when adults had used e-cigarettes .  Design We used the 2014 Minnesota Adult Tobacco Survey , a r and om digit dial population survey ( n=9304 adults ) . Questions included ever using e-cigarettes , number of days used in the past 30 days and reasons for use . Smoking status was determined by combustible cigarette use . Histograms of e-cigarette use were visually inspected for current , former and never smokers with any 30-day e-cigarette use . Different definitions of current use were compared . Results Use ≤5 days in the past 30 days demarcated a cluster of infrequent users at the low end of the distribution . Among those with use in the past 30 days , infrequent users were the majorities of current ( 59 % ) and never smokers ( 89.5 % ) , but fewer than half of former smokers ( 43.2 % ) . Infrequent users were more likely to cite curiosity and less likely to cite quitting/cutting down other tobacco use as reasons for use . Conclusions Defining adult prevalence as any use in the past 30 days may include experimenters unlikely to continue use , and is of question able utility for population surveillance of public health trends over time . Defining prevalence as > 5 days excludes those infrequent users PURPOSE Electronic cigarettes ( e-cigarettes ) are a new type of device that delivers vaporized nicotine without the tobacco combustion of regular cigarettes . We sought to underst and awareness of and willingness to try e-cigarettes among adolescent males , a group that is at risk for smoking initiation and may use e-cigarettes as a " gateway " to smoking . METHODS A national sample of 11 - 19-year-old males ( n = 228 ) completed an online survey in November 2011 . We recruited participants through their parents , who were members of a panel of U.S. households constructed using r and om-digit dialing and addressed-based sampling . RESULTS Only two participants ( < 1 % ) had previously tried e-cigarettes . Among those who had not tried e-cigarettes , most ( 67 % ) had heard of them . Awareness was higher among older and non-Hispanic adolescents . Nearly 1 in 5 ( 18 % ) participants were willing to try either a plain or flavored e-cigarette , but willingness to try plain versus flavored varieties did not differ . Smokers were more willing to try any e-cigarette than nonsmokers ( 74 % vs. 13 % ; OR 10.25 , 95 % CI 2.88 , 36.46 ) . Nonsmokers who had more negative beliefs about the typical smoker were less willing to try e-cigarettes ( OR .58 , 95 % CI .43 , .79 ) . CONCLUSIONS Most adolescent males were aware of  e-cigarettes  , and a substantial minority were willing to try them . Given that even experimentation with e-cigarettes could lead to nicotine dependence and subsequent use of other tobacco products , regulatory and behavioral interventions are needed to prevent " gateway " use by adolescent nonsmokers . Campaigns promoting negative images of smokers or FDA bans on sales to youth may help deter use Background More US adolescents use e-cigarettes than smoke cigarettes . Research suggests flavoured e-cigarettes appeal to youth , but little is known about perceptions of and reasons for attraction to specific flavours . Methods A national sample of adolescents ( n=1125 ) ages 13–17 participated in a phone survey from November 2014 to June 2015 . We r and omly assigned adolescents to respond to survey items about 1 of 5 e-cigarette flavours ( tobacco , alcohol , menthol , c and y or fruit ) and used regression analysis to examine the impact of flavour on interest in trying e-cigarettes and harm beliefs . Results Adolescents were more likely to report interest in trying an e-cigarette offered by a friend if it were flavoured like menthol ( OR=4.00 , 95 % CI 1.46 to 10.97 ) , c and y ( OR=4.53 , 95 % CI 1.67 to 12.31 ) or fruit ( OR=6.49 , 95 % CI 2.48 to 17.01 ) compared with tobacco . Adolescents believed that fruit-flavoured e-cigarettes were less harmful to health than tobacco-flavoured e-cigarettes ( p<0.05 ) . Perceived harm mediated the relationship between some flavours and interest in trying e-cigarettes . A minority of adolescents believed that e-cigarettes did not have nicotine ( 14.6 % ) or did not know whether they had nicotine ( 3.6 % ) ; these beliefs did not vary by flavour . Discussion C and y-flavoured , fruit-flavoured and menthol-flavoured e-cigarettes appeal to adolescents more than tobacco-flavoured or alcohol-flavoured e-cigarettes . This appeal is only partially explained by beliefs about reduced harm . Given adolescents ' interest in trying e-cigarettes with certain flavours , policymakers should consider restricting advertisements promoting flavoured products in media that reach large numbers of young people . Future research should examine other reasons for the appeal of individual flavours , such as novelty and perceived luxury Background The potential of electronic nicotine delivery systems ( ENDS ) to reduce the cardiovascular and other disease risks of smoking is of great interest . While many smokers report using ENDS for cessation , their impact under real-world use patterns and conditions on adult smokers ’ quitting behavior is uncertain . The objective of this study was to generate more recent and comprehensive evidence on the effect of “ real world ” ENDS use on the population quit rates of adult smokers while taking account of frequency and duration of use , device type , e-liquid flavor , and reasons for use . Methods and findings We conducted a population -based , prospect i ve cohort study of a r and om probability sample of 1284 U.S. adult smokers recruited in August/September 2015 and re-contacted one-year later ( September 2016 ) from GfK ’s KnowledgePanel , a national , probability-based web-panel design ed to be representative of non-institutionalized U.S. adults . Among the 1081 baseline smokers who remained members of KnowledgePanel , 858 completed the follow-up survey . The primary outcome was smoking abstinence for at least 30 days prior to follow-up . Secondary outcomes were making a quit attempt during the 12-month study period and number of cigarettes smoked per day at follow-up . The adjusted odds of quitting smoking were lower for those that used ENDS at baseline ( 9.4 % , 95 % CI = 5.22%-16.38 % ; AOR = 0.30 , 95 % CI = 0.13–0.72 ) compared to smokers who did not use at ENDS ( 18.9 % , 95 % CI = 14.24%-24.68 % ) . Smokers who used ENDS daily at some point during the study period were also less likely to quit smoking than nonusers ( AOR = 0.17 ; 95 % CI = 0.04–0.82 ) . Limited ability to draw causal inferences from the observational design and a lack 
    Output:
    
This review provides summary data on the role of non-menthol flavours in e-cigarette perceptions and use .
Consistent evidence shows that flavours attract both youth and adults to use e-cigarettes .
Given the clear findings that such flavours increase product appeal , willingness to try and initiation among youth , banning non-menthol flavours in e-cigarettes may reduce youth e-cigarette use .