title: Strategies used for measuring long-term control in atopic dermatitis trials: A systematic review.
abstract: Atopic dermatitis (AD) is a chronic inflammatory skin disease. There are no standardized methods for capturing long-term control of AD.
  
  
  
  We sought to identify how long-term control has been captured in published randomized controlled trials (RCTs). Results will initiate consensus discussions on how best to measure long-term control in the core outcome set for AD.
  
  
  
  We conducted a systematic review of RCTs of AD treatments published between 2000 and 2013, with a follow-up period of 3 months or longer, at least 1 outcome measure recorded at 3 or more time points, full article available, and published in English.
  
  
  
  In all, 101 of 353 RCTs were eligible. Methods to capture long-term control included: repeated measurement of AD outcomes (92 RCTs; 91%), use of AD medication (29 RCTs; 28.7%), and AD flares/remissions (26 RCTs; 25.7%). Repeated measurements of AD outcomes were typically collected 3 to 5 times during a trial, but analysis methods often failed to make best use of the data. Time to first flare was most commonly used for trials including flare data (21/52). Medication use was recorded based on quantity, potency, and frequency of application.
  
  
  
  We included RCT data only.
  
  
  
  This review illustrates the difficulties in measuring long-term control, and points to the need for improved harmonization of outcomes.
authors: Center of Evidence-based Dermatology, University of Nottingham, Nottingham, United Kingdom; Department of Dermatology, Centre Hospitalier Universitaire (CHU) de Nantes, Nantes, France.
authors: Sebastien
authors: S
authors: Barbarot
authors: Center of Evidence-based Dermatology, University of Nottingham, Nottingham, United Kingdom.
authors: Natasha K
authors: NK
authors: Rogers
authors: Department of Dermatology, University of California, San Francisco, California.
authors: Katrina
authors: K
authors: Abuabara
authors: Department of Dermatology, Centre Hospitalier Universitaire (CHU) de Nantes, Nantes, France.
authors: Helene
authors: H
authors: Aubert
authors: Center of Evidence-based Dermatology, University of Nottingham, Nottingham, United Kingdom.
authors: Joanne
authors: J
authors: Chalmers
authors: Population-based Dermatology Research Unit, St John's Institute of Dermatology, Guy's and St Thomas' National Health Service Foundation Trust and King's College London, London, United Kingdom.
authors: Carsten
authors: C
authors: Flohr
authors: Department of Dermatology, Oregon Health and Science University, Portland, Oregon.
authors: Jon
authors: J
authors: Hanifin
authors: Study Center Italian Group for Epidemiologic Research in Dermatology and Department of Dermatology, Azienda Ospedaliera Papa Giovanni XXIII, Bergamo, Italy.
authors: Luigi
authors: L
authors: Naldi
authors: Departments of Dermatology and Biostatistics and Epidemiology, University of Pennsylvania, Perelman School of Medicine, Philadelphia, Pennsylvania.
authors: David J
authors: DJ
authors: Margolis
authors: Dermatology, Paul Sabatier University and Hôpital Larrey, Toulouse, France.
authors: Carle
authors: C
authors: Paul
authors: School of Social and Community Medicine, University of Bristol, Bristol, United Kingdom.
authors: Matthew J
authors: MJ
authors: Ridd
authors: Department of Dermatology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
authors: Marie-Louise Anna
authors: MA
authors: Schuttelaar
authors: Department of Dermatology, Oregon Health and Science University, Portland, Oregon.
authors: Eric
authors: E
authors: Simpson
authors: Dermatology, Paul Sabatier University and Hôpital Larrey, Toulouse, France.
authors: Marie
authors: M
authors: Tauber
authors: Department of Dermatology, University of Tartu, Tartu, Estonia.
authors: Annika
authors: A
authors: Volke
authors: Department of Dermatology, Venereology, and Allergy, University Hospital Schleswig-Holstein, Campus Kiel, Kiel, Germany.
authors: Stephan
authors: S
authors: Weidinger
authors: Center of Evidence-based Dermatology, University of Nottingham, Nottingham, United Kingdom.
authors: Sally R
authors: SR
authors: Wilkes
authors: Department of Dermatology and Allergy, Ludwig-Maximilian University Munich, Munich, Germany.
authors: Andreas
authors: A
authors: Wollenberg
authors: Center of Evidence-based Dermatology, University of Nottingham, Nottingham, United Kingdom. Electronic address: kim.thomas@nottingham.ac.uk.
authors: Kim S
authors: KS
authors: Thomas
mesh_terms: D016206:Databases, Bibliographic; D003876:Dermatitis, Atopic / Q000188:drug therapy*; D003879:Dermatologic Agents / Q000627:therapeutic use*; D018450:Disease Progression; D006801:Humans; D016032:Randomized Controlled Trials as Topic / Q000379:methods* / Q000592:standards; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D003879:Dermatologic Agents
keywords: atopic dermatitis; atopic eczema; flares; long-term control; outcome measures; randomized controlled trials; systematic review