Background:
Nurses can positively influence in tobacco prevention and treatment. It is during undergraduate-years when students should acquire knowledge, and skills in smoking cessation; however, nursing students' knowledge has not been yet assessed in Catalonia. Therefore, the objective of our study was to analyse the smoking prevalence of nursing students and the determinants, consumption pattern, training received and knowledge in tobacco control.

Methods:
Multicentre prevalence study by self-completion questionnaire, directed to all students enrolled in the 15 nursing schools in Catalonia during 2015-16. The 57.2% of the students participated in our study (N=4,381). The questionnaire included questions about tobacco use, training and knowledge on smoking cessation. Logistic regression models (OR and 95%CI) were used to assess the association within tobacco consumption and the independent variables (age and studying year).

Results:
The participation by nursing schools was heterogeneous, varying from 35.4% to 81.9%. The 83.2% of the sample were women. The 31.2% of the students smoked. Differences in prevalences were only found by schools (22.4-41.5%;p< 0.01). Most students received training on tobacco consumption: smoking risks (80.6%) and secondhand smoke (86.3%), but not on treatment (32.4%). The 98.1% knew that smoking was an addiction and the 98.4% that secondhand smoke was unhealthy. Being smoker was related to an older age (OR=1.25;CI:1.05-1.49 from 20 to 21 years old; OR=1.82;CI:1.54-2.16 in ≥22 years old), higher level of self-reported knowledge (OR=1.31,CI:1.11-1.55) and with a lower evaluated knowledge (OR=0.81,CI:0.67-0.97).

Conclusions:
The smoking prevalence among nursing students in Catalonia is high and increases with age, without differences by sex. Although students affirmed having received training on tobacco consumption during its degree, their level of knowledge is low for treatment. Smokers have overestimated their training since they had lower evaluated knowledge. It would be recommendable to impart training that qualifies nursing students to help smokers to quit.