Effectiveness of a School-Based 'Tobacco Free' Intervention on Adolescents' Knowledge and Exposure to Second Hand Tobacco Smoke - A Multiphase Study.

Background: There is no safe level of exposure to second hand tobacco smoke (SHS). The World Health Organization has stressed that 100% smoke-free environments are the only effective way to protect the population from the harmful effects of exposure to SHS.

Design: A multiphase study with a descriptive cross-sectional questionnaire phase 1  and a phase 2 cluster randomized controlled trial (RCT), conceptualized to determine the effectiveness of a school-based 'tobacco free' health education intervention on adolescents' knowledge and attitude towards SHS.

Methods: Baseline assessment will include a questionnaire followed by estimation of salivary cotinine levels. The experimental arm will receive the 'tobacco free' intervention, which includes 40 min health education session delivered once a week for 3 consecutive weeks. Participants will also be given 'take home brochures' every week containing messages on the effects of tobacco and how to make their homes smoke-free. The sample of 250 participants, for the Phase 2 RCT, with salivary cotinine levels of > 0.1 ng/mL will be selected from the participants of the Phase 1 study. The effect of the intervention will be quantitatively assessed by estimating the salivary cotinine levels after the intervention. Participants in the control arm will receive conventional standard health education once.

Conclusion: This research will help in assessing if there is any change in the salivary cotinine levels and the knowledge, attitude and behaviour scores after the health educational intervention and help in developing an effective school-based 'tobacco free' intervention program which could be incorporated into the school curriculum. This study has received the Public Health Research Initiative (PHRI) Research Grant of Rs. 18,99,205 and is registered with the Clinical Trial Registry of India (CTRI) with number CTRI/2018/09/015706 (Registered on 13/09/2018). Ethical approval has been obtained from The Institutional Ethics Committee (No.17021 dated 13 march 2017).