Article Text

Impact of expanding smoke-free policies beyond enclosed public places and workplaces on children’s tobacco smoke exposure and respiratory health: protocol for a systematic review and meta-analysis
  1. Márta K Radó1,2,
  2. Famke JM Mölenberg2,
  3. Aziz Sheikh3,4,
  4. Christopher Millett5,
  5. Wichor M Bramer6,
  6. Alex Burdorf2,
  7. Frank J van Lenthe2,
  8. Jasper V Been1,2
  1. 1Department of Paediatrics, Erasmus MC - Sophia Children's Hospital, University Medical Centre Rotterdam, Rotterdam, Netherlands
  2. 2Department of Public Health, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, Netherlands
  3. 3Usher Institute, The University of Edinburgh, Edinburgh, United Kingdom
  4. 4Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
  5. 5Public Health Policy Evaluation Unit, School of Public Health, Imperial College London, London, United Kingdom
  6. 6Medical Library, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, Netherlands
  1. Correspondence to Dr Jasper V Been; j.been{at}


Introduction Tobacco smoke exposure (TSE) has considerable adverse respiratory health impact among children. Smoke-free policies covering enclosed public places are known to reduce child TSE and benefit child health. An increasing number of jurisdictions are now expanding smoke-free policies to also cover outdoor areas and/or (semi)private spaces (indoor and/or outdoor). We aim to systematically review the evidence on the impact of these ‘novel smoke-free policies’ on children’s TSE and respiratory health.

Methods and analysis 13 electronic databases will be searched by two independent reviewers for eligible studies. We will consult experts from the field and hand-search references and citations to identify additional published and unpublished studies. Study designs recommended by the Cochrane Effective Practice and Organisation of Care (EPOC) group are eligible, without restrictions on the observational period, publication date or language. Our primary outcomes are: self-reported or parental-reported TSE in places covered by the policy; unplanned hospital attendance for wheezing/asthma and unplanned hospital attendance for respiratory infections. We will assess risk of bias of individual studies following the EPOC or Risk Of Bias In Non-randomised Studies of Interventions tool, as appropriate. We will conduct separate random effects meta-analyses for smoke-free policies covering (1) indoor private places, (2) indoor semiprivate places, (3) outdoor (semi)private places and (4) outdoor public places. We will assess whether the policies were associated with changes in TSE in other locations (eg, displacement). Subgroup analyses will be conducted based on country income classification (ie, high, middle or low income) and by socioeconomic status. Sensitivity analyses will be undertaken via broadening our study design eligibility criteria (ie, including non-EPOC designs) or via excluding studies with a high risk of bias. This review will inform policymakers regarding the implementation of extended smoke-free policies to safeguard children’s health.

Ethics and dissemination Ethical approval is not required. Findings will be disseminated to academics and the general public.

PROSPERO registration number CRD42020190563.

  • health policy
  • child protection
  • community child health
  • public health
  • respiratory infections

This is an open access article distributed in accordance with the Creative Commons Attribution 4.0 Unported (CC BY 4.0) license, which permits others to copy, redistribute, remix, transform and build upon this work for any purpose, provided the original work is properly cited, a link to the licence is given, and indication of whether changes were made. See:

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  • Twitter @MartaRado, @FamkeMolenberg, @JasperBeen

  • Contributors JVB secured funding for this work. All authors contributed to the conceptualisation of the review and developed the methods. MR, FM and JVB drafted the manuscript and AS, CM, WMB, AB and FJVL provided feedback on manuscript drafts. JVB and WMB developed the search strategy. All authors approved the manuscript.

  • Funding This study is funded by a project grant from the Dutch Heart Foundation, Lung Foundation Netherlands, Dutch Cancer Society, Dutch Diabetes Research Foundation and the Netherlands Thrombosis Foundation. The Public Health Policy Evaluation Unit at Imperial College London is grateful for the support of the NIHR School of Public Health Research.

  • Competing interests None declared.

  • Patient and public involvement Patients and/or the public were not involved in the design, or conduct, or reporting, or dissemination plans of this research.

  • Patient consent for publication Not required.

  • Provenance and peer review Not commissioned; externally peer reviewed.

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