A mHealth intervention (mTB-Tobacco) for smoking cessation in people with drug-sensitive pulmonary tuberculosis: protocol for an adaptive design, clusterrandomised controlled trial (Quit4TB)

Introduction: People with tuberculosis (TB) who continue to smoke are more likely to have poor health outcomes than those who quit. Established smoking cessation approaches such as mHealth may help TB patients quit smoking. This paper summarises the methodology proposed to assess the effectiveness and cost-effectiveness of mTB-Tobacco (an mHealth intervention) in helping TB patients stop smoking and have improved health outcomes. Methods and analysis: A two-arm, parallel, open-label, multi-centre, cluster randomised, two-stage adaptive design trial is proposed to first evaluate the superiority of mTB-Tobacco, compared with usual care and then the non-inferiority of mTB-tobacco compared with face-to-face behaviour support. Study settings include TB treatment centres in Bangladesh and Pakistan. The study population includes adult patients, newly diagnosed (within four weeks) with pulmonary TB disease, daily smokers, willing to quit, and have access to mobile phones. The primary outcome includes biochemically verified continuous smoking abstinence assessed at 6 months per Russell Standard. A generalised linear mixed-effects model will be used to assess the impact of mTB-Tobacco intervention on continuous outcomes, incorporating fixed effects for the intervention, random effects for clusters, and relevant covariates. Cost-effectiveness analysis will be done to estimate the cost per quitter and cost per QALY gained, calculate the incremental cost-effectiveness ratios (ICER) to establish the value for money for mTB-Tobacco. Ethics and dissemination This trial will be conducted in compliance with ICH-GCP guidelines and the Declaration of Helsinki. The study has been approved by the ethics committees of the University of Edinburgh Medical School Research Ethics Committee (EMREC) of UK, the Bangladesh Medical Research Council (BMRC) and the National Bioethics Committee (PMRC) of Pakistan. Funding: The study is funded by the National Institute of Health Research (NIHR) UK under a research award named NIHR Global Health Research Unit on Respiratory Health (RESPIRE) (Award ID: NIHR132826)