You will be presented with a collection of medical randomized controlled trial (RCT) reports addressing a shared clinical question -- for instance, the efficacy of a medical intervention on a disease or condition. Given the titles and abstracts of these reports, your task is to generate the conclusion of the systematic review article synthesizing the key findings. Your conclusion should be a few sentences long. In your response, include only the conclusion and no other text. The RCT reports are below.



Title 1:
Acute impact of active and passive electronic cigarette smoking on serum cotinine and lung function
Abstract 1:
Abstract Context : Electronic cigarettes ( e-cigarettes ) are becoming increasingly popular yet their effects on health remain unknown . Objective : To conduct the first comprehensive and st and ardized assessment of the acute impact of active and passive e-cigarette smoking on serum cotinine and lung function , as compared to active and passive tobacco cigarette smoking . Material s and methods : Fifteen smokers ( ≥15 cigarettes/day ; seven females ; eight males ) and 15 never-smokers ( seven females ; eight males ) completed this repeated- measures controlled study . Smokers underwent a control session , an active tobacco cigarette ( their favorite br and ) smoking session and an active e-cigarette smoking session .  Never-smokers underwent a control session , a passive tobacco cigarette smoking session and a passive e-cigarette smoking session . Serum cotinine , lung function , exhaled carbon monoxide and nitric oxide were assessed . The level of significance was set at p ≤ 0.001 to adjust for multiple comparisons . Results : e-Cigarettes and tobacco cigarettes generated similar ( p > 0.001 ) effects on serum cotinine levels after active ( 60.6 ± 34.3 versus 61.3 ± 36.6 ng/ml ) and passive ( 2.4 ± 0.9 versus 2.6 ± 0.6 ng/ml ) smoking . Neither a brief session of active e-cigarette smoking ( indicative : 3 % reduction in FEV1/FVC ) nor a 1 h passive e-cigarette smoking ( indicative : 2.3 % reduction in FEV1/FVC ) significantly affected the lung function ( p > 0.001 ) . In contrast , active ( indicative : 7.2 % reduction in FEV1/FVC ; p < 0.001 ) but not passive ( indicative : 3.4 % reduction in FEV1/FVC ; p = 0.005 ) tobacco cigarette smoking undermined lung function . Conclusion : Regarding short-term usage , the studied e-cigarettes generate smaller changes in lung function but similar nicotinergic impact to tobacco cigarettes . Future research should target the health effects of long-term e-cigarette usage , including the effects of nicotine dosage


Title 2:
Alternative tobacco product use and smoking cessation among homeless youth in los angeles county.
Abstract 2:
INTRODUCTION Approximately 70 % of homeless youth smoke cigarettes , but their use of alternative tobacco products ( ATPs ) is unknown . This paper reports on ATP use among past-month smokers in Los Angeles County , including whether it differs by demographic characteristics , homelessness severity , past-year quit attempts , and readiness to quit smoking . Given the growing popularity of e-cigarettes , we also report on perceptions of harm and reasons for using this product . METHODS We surveyed 292 unaccompanied homeless youth who were r and omly sample d from street sites . Participants had smoked at least 100 cigarettes during their lifetime and 1 cigarette during the past month . RESULTS Seventy-two percent of youth reported past-month ATP use ( e-cigarettes = 51 % ; little cigars/cigarillos = 46 % ; hookah = 31 % ; other smokeless tobacco product = 24 % ; chewing tobacco/moist snuff = 19 % ) . Current ATP use was unrelated to most demographic characteristics or having a past-year quit attempt . However , youth who planned to quit smoking in the next 30 days were significantly less likely to report current use of hookahs , other smokeless tobacco products , or e-cigarettes . Among lifetime e-cigarette users , the most common reasons for use included not having to go outside to smoke ( 38 % ) and being able to deal with situations or places where they can not smoke ( 36 % ) ; it was less common to report using e-cigarettes to quit smoking ( 17%-18 % ) . DISCUSSION Dual use of ATPs among homeless youth smokers is common and is more likely among those who have no immediate plans to quit smoking . Effective and easily disseminable strategies for reducing all forms of tobacco use among homeless youth are urgently needed
This literature review reported that the usage of these  e-cigarettes  was high among this population and recorded a wide variety of reasons for using e-cigarettes .
Reducing tobacco use , considering e-cigarette as less harmful , less addictive , for pleasure and peer influence , lower cost and curiosity were the most commonly reported reasons .