TY - JOUR T1 - “Trends in worldwide asthma prevalence” JF - European Respiratory Journal JO - Eur Respir J DO - 10.1183/13993003.02094-2020 SP - 2002094 AU - M. Innes Asher AU - Luis García-Marcos AU - Neil E. Pearce AU - David P. Strachan Y1 - 2020/01/01 UR - http://erj.ersjournals.com/content/early/2020/09/17/13993003.02094-2020.abstract N2 - This review of trends in worldwide asthma prevalence starts with defining how asthma prevalence s measured in populations and how it is analysed. Four population studies of asthma across at least two regions are described: European Community Respiratory Health Survey (ECRHS), The International Study of Wheezing in Infants (EISL), The International Study of Asthma and Allergies in Childhood (ISAAC) and the World Health Survey (WHS). Two of these (ISAAC and WHS) covered all the regions of the world; each using its own standardised questionnaire-based methodology with cross-sectional study design, suitable for large populations. EISL (2005 and-2012) and ISAAC (1996–1997 and 2002–2003) have undertaken a second cross sectional population survey from which trends are available: EISL in three centres in two countries; ISAAC 106 centres in 56 countries (13–14 year olds) and 66 centres in 37 countries (6–7 year olds). Key results from these studies are presented. Unfortunately, there is no new worldwide new data outside of EISL since 2003. Global Burden of Disease estimates of asthma prevalence have varied greatly. Recent reliable worldwide data on asthma prevalence and trends is needed; the Global Asthma Network Phase I will provide this in 2021.FootnotesThis manuscript has recently been accepted for publication in the European Respiratory Journal. It is published here in its accepted form prior to copyediting and typesetting by our production team. After these production processes are complete and the authors have approved the resulting proofs, the article will move to the latest issue of the ERJ online. Please open or download the PDF to view this article.Conflict of interest: Dr. ASHER has nothing to disclose.Conflict of interest: Dr. Garcia-Marcos has nothing to disclose.Conflict of interest: Dr. Pearce has nothing to disclose.Conflict of interest: Dr. Strachan has nothing to disclose. ER -