ACR Meeting Abstracts

ACR Meeting Abstracts

Abstract Number: 2706

Discriminant Validity and Reliability of World Scleroderma Foundation (WSF) Definition of Skin Ulcers in Systemic Sclerosis

Yossra A Suliman1, Cosimo Bruni2, Sindhu Johnson3, Suzanne Kafaja4, Emanuela Praino5, Dinesh Khanna6, Yannick Allanore7, Murray Baron8, Jonathan Grotts9, Thomas Krieg10, Ariane L. Herrick11, Christopher P. Denton12, Marco Matucci-Cerinic13 and Daniel E. Furst14, 1Rheumatology and Rehabilitation dept., Rheumatology and Rehabilitation dept. Assiut university hospital, Assiut Egypt, Assiut, Egypt, 2Department of Experimental and Clinical Medicine, Division of Rheumatology, University of Florence, Firenze, Italy, 3Toronto Scleroderma Program, Toronto Western Hospital, Mount Sinai Hospital, University of Toronto, Toronto, ON, Canada, 4David Geffen School of Medicine, UCLA, Los Angeles, CA, 5DIM, Rheumatology Unit - D.E.T.O. - University of Bari (ITALY), Bari, Italy, 6Division of Rheumatology, Department of Internal Medicine, University of Michigan Scleroderma Program, University of Michigan, Ann Arbor, MI, 7Service de Rhumatologie A, Hôpital Cochin, Paris, France, 8Rheumatology, Jewish General Hospital, Montreal, QC, Canada, 9Biostatistics, University of California Los Angeles, Los Angeles, CA, 10Universität zu Köln, Köln, Germany, 11Centre for Musculoskeletal Research, Division of Musculoskeletal and Dermatological Sciences, The University of Manchester, Manchester, United Kingdom, 12UCL Division of Medicine, Royal Free Campus, London, United Kingdom, 13Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy, 14Medicine, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, CA

Meeting: 2018 ACR/ARHP Annual Meeting

Keywords:

Session Information

Date: Tuesday, October 23, 2018

Title: Systemic Sclerosis and Related Disorders – Clinical Poster III

Session Type: ACR Poster Session C

Session Time: 9:00AM-11:00AM

Background/Purpose:

To date, there is lack of a uniform definition of systemic sclerosis related skin ulcer (SSc-skin ulcer) for use in clinical trials. Our group previously published a consensus driven definition of SSc-skin ulcer under the patronage of WSF(1) . The definition was based on a systematic literature review followed by a nominal group technique to establish consensus among SSc experts. Face validity and feasibility were demonstrated. However, further validation of the WSF skin ulcer definition is needed.

Aim: to establish the sensitivity and specificity of the proposed WSF clinical definition of SSc-skin ulcers and evaluate Its reliability among investigators. 

Step I: To determine the ability to discriminate between SSc-Skin ulcers, SSc non-ulcer lesions and non SSc lesions. 

Step II: To examine the inter-rater and Intra-rater reliability of the WSF definition among investigators.

Methods:

Four hundred images {200 SSc skin lesions (ulcers and non-ulcers), 200 non-SSc skin lesions} were evaluated by two highly qualified SSc experts and their scoring were considered the gold standard scores. 

Step I: 10 investigators with different levels of expertise in SSc were included to utilize the definition in discrimination between SSc-skin ulcers from other lesions (SSc non-ulcers and non-SSc lesions) as compared to gold standard. Each investigator scored 40 images.

 Step II: A total of 45 images were sent to each of the 10 investigators. Twenty (20) images per investigator evaluated in step I, were examined again for intra-investigator reliability.  Twenty-five (25) images (the same images examined across the 10 investigators) were used to examine inter-investigator reliability. 

Results:

Step I:  

–For discriminating SSc-skin ulcers from SSc non-ulcer lesions: sensitivity was 78% and specificity was 94 %

-For discriminating SSc-ulcers from non SSc– ulcer lesions: sensitivity was 78% and specificity was 100%

 Step II:

Intra-rater reliability using ICC was 0.99, with kappa agreement of 0.89 (excellent)

Inter-rater reliability using Fleiss Kappa was 0.346 (only fair, given a range of 0-1.0). 

Discusssion:

 As is the case for mRSS, repeated training sessions prior to starting a clinical trial may decrease variability among investigators .

Conclusion: Discrimination among a group of rheumatologists with varying SSc experience for differentiating between SS-ulcers, SSc-non-ulcers and non-SSc lesions was very good(sensitivity) to excellent (specificity)

As for other clinical SSc measures  (e.g. mRSS), it will be necessary in clinical trials to have the same investigator examining a given patient over time, as inter-rater reliability is not sufficient.

Ref:

Y Suliman et al., Defining Skin Ulcers in Systemic Sclerosis: Systematic Literature Review and Proposed World Scleroderma Foundation (WSF) Definition. JSRD Vol 2, Issue 2.

World Scleroderma Foundation(WSF) skin ulcer definition:

1.    Loss of epidermal covering with a break in the basement membrane (which separates dermis from the epidermis). It appears clinically as visible blood vessels, fibrin, granulation tissue and/or underlying deeper structures (e.g. muscle, ligament, fat), or as it would appear on debridement.

2.    This excludes: Scar, Abrasion, Incision, Laceration, Fissure, Infected ulcer, ulcer with underlying calcinosis, and gangrenous ulcers
Disclosure: Y. A. Suliman, None; C. Bruni, None; S. Johnson, Roche, Bayer, Boehringer, BMS, NIH, Merck, 9; S. Kafaja, None; E. Praino, None; D. Khanna, Eicos Sciences, 1,Pfizer, Inc., 2,Horizon, 2,BMS, 2,Actelion, 5,Bayer, 5,Bayer, 2,Corbus, 5,Cytori, 5,EMD Serono, 5,Genentech, Inc., 5,Sanofi-Aventis, 5,GSK, 5,Boehringer Ingelheim, 5; Y. Allanore, Actelion, Boehringer, Roche, Sanofi, Inventiva, Medac, Bayer, BMS, Pfizer, 2, 5; M. Baron, None; J. Grotts, None; T. Krieg, actelion, 2, 8; A. L. Herrick, Actelion, 2,Medical Research Council (MRC), 2; C. P. Denton, Roche, Actelion, GlaxoSmithKline, Sanofi-Aventis, Inventiva, SCL Behring, Boehringer-Ingelheim, Bayer., 5; M. Matucci-Cerinic, None; D. E. Furst, None.

To cite this abstract in AMA style:

Suliman YA, Bruni C, Johnson S, Kafaja S, Praino E, Khanna D, Allanore Y, Baron M, Grotts J, Krieg T, Herrick AL, Denton CP, Matucci-Cerinic M, Furst DE. Discriminant Validity and Reliability of World Scleroderma Foundation (WSF) Definition of Skin Ulcers in Systemic Sclerosis [abstract]. Arthritis Rheumatol. 2018; 70 (suppl 9). https://acrabstracts.org/abstract/discriminant-validity-and-reliability-of-world-scleroderma-foundation-wsf-definition-of-skin-ulcers-in-systemic-sclerosis/. Accessed .

« Back to 2018 ACR/ARHP Annual Meeting

ACR Meeting Abstracts - https://acrabstracts.org/abstract/discriminant-validity-and-reliability-of-world-scleroderma-foundation-wsf-definition-of-skin-ulcers-in-systemic-sclerosis/