title: How to Establish and Follow up a Large Prospective Cohort Study in the 21st Century--Lessons from UK COSMOS.
abstract: Large-scale prospective cohort studies are invaluable in epidemiology, but they are increasingly difficult and costly to establish and follow-up. More efficient methods for recruitment, data collection and follow-up are essential if such studies are to remain feasible with limited public and research funds. Here, we discuss how these challenges were addressed in the UK COSMOS cohort study where fixed budget and limited time frame necessitated new approaches to consent and recruitment between 2009-2012. Web-based e-consent and data collection should be considered in large scale observational studies, as they offer a streamlined experience which benefits both participants and researchers and save costs. Commercial providers of register and marketing data, smartphones, apps, email, social media, and the internet offer innovative possibilities for identifying, recruiting and following up cohorts. Using examples from UK COSMOS, this article sets out the dos and don'ts for today's cohort studies and provides a guide on how best to take advantage of new technologies and innovative methods to simplify logistics and minimise costs. Thus a more streamlined experience to the benefit of both research participants and researchers becomes achievable.
authors.affiliation: MRC-PHE Centre for Environment and Health, Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, St Mary's Campus, London, United Kingdom.
authors.forename: Mireille B
authors.initials: MB
authors.lastname: Toledano
authors.affiliation: MRC-PHE Centre for Environment and Health, Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, St Mary's Campus, London, United Kingdom.
authors.forename: Rachel B
authors.initials: RB
authors.lastname: Smith
authors.affiliation: MRC-PHE Centre for Environment and Health, Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, St Mary's Campus, London, United Kingdom.
authors.forename: James P
authors.initials: JP
authors.lastname: Brook
authors.affiliation: MRC-PHE Centre for Environment and Health, Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, St Mary's Campus, London, United Kingdom.
authors.forename: Margaret
authors.initials: M
authors.lastname: Douglass
authors.affiliation: MRC-PHE Centre for Environment and Health, Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, St Mary's Campus, London, United Kingdom.
authors.forename: Paul
authors.initials: P
authors.lastname: Elliott
mesh_terms: D015331:Cohort Studies; D034742:Electronic Mail; D005500:Follow-Up Studies; D006801:Humans; D020407:Internet; D064887:Observational Studies as Topic; D018579:Patient Selection; D011446:Prospective Studies; D012107:Research Design