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The Validated Investigator Global Assessment for Atopic Dermatitis (vIGA-AD): The development and reliability testing of a novel clinical outcome measurement instrument for the severity of atopic dermatitis.

Journal of the American Academy of Dermatology

Authors: Eric Simpson, Robert Bissonnette, Lawrence F Eichenfield, Emma Guttman-Yassky, Brett King, Jonathan I Silverberg, Lisa A Beck, Thomas Bieber, Kristian Reich, Kenji Kabashima, Marieke Seyger, Elaine Siegfried, Georg Stingl, Steven R Feldman, Alan Menter, Peter van de Kerkhof, Gil Yosipovitch, Carle Paul, Philippe Martel, Ariane Dubost-Brama, John Armstrong, Rajeev Chavda, Steve Frey, Yolandi Joubert, Marina Milutinovic, Anne Parneix, Henrique D Teixeira, Chen-Yen Lin, Luna Sun, Paul Klekotka, Brian Nickoloff, Yves Dutronc, Lotus Mallbris, Jonathan M Janes, Amy M DeLozier, Fabio P Nunes, Amy S Paller

BACKGROUND: An Investigator Global Assessment (IGA) is recommended by health agencies for drug registration in atopic dermatitis (AD). Current IGA scales lack standardization.

OBJECTIVES: To develop an IGA scale, training module, and clinical certification examination for use in AD trials; establish content validity; and assess reliability.

METHODS: Expert dermatologists participated in the development of the validated IGA for AD (vIGA-AD). Reliability (interrater and intrarater) was assessed by 2 web-based surveys. Clinical certification for investigators consisted of a training module and examination.

RESULTS: Expert consensus was achieved around a 5-point IGA scale including morphologic descriptions, and content validity was established. Survey 1 showed strong interrater reliability (Kendall's coefficient of concordance W [Kendall's W], 0.809; intraclass correlation [ICC], 0.817) and excellent agreement (weighted kappa, 0.857). Survey 2, completed 5 months after training of dermatologists, showed improvements in scale reliability (Kendall's W, 0.819; ICC, 0.852; weighted kappa, 0.889). In this study, 627 investigators completed vIGA-AD training and certification.

LIMITATIONS: Ratings were assessed on photographs.

CONCLUSION: A validated IGA scale and training module were developed with the intent of harmonizing assessment of disease severity in AD trials. Strong reliability and excellent agreement between assessments were observed.

Copyright © 2020. Published by Elsevier Inc.

PMID: 32344071

Participating cluster members