Inter‐ and Intrarater Reliability of the Hurley Staging for Hidradenitis Suppurativa

Abstract

Background

Hidradenitis suppurativa (HS) is a chronic, inflammatory and recurrent skin disease. Different staging instruments have been suggested, but none has achieved universal acceptance. Despite the fact that the Hurley staging is one of the most widely applied HS disease severity staging instruments, it has not been validated.

Objective

To determine the inter‐ and intrarater reliability of the Hurley staging.

Methods

Fifteen raters (5 plastic surgeons, 5 general surgeons and 5 dermatologists) independently staged 30 photos of HS patients according to the Hurley staging at T1 and T2. Reliability was assessed using kappa statistics and multivariable logistic regressions were used to determine independent risk factors for photos with discordant staging.

Results

Interrater reliability was moderate for the three stages of HS (κ = 0·59; 95% CI, 0·48‐0·70). It was moderate for Hurley stage I (κ = 0·45; 95% CI, 0·32‐0·55) and stage II (κ = 0·51; 95% CI, 0·31‐0·71), and it was almost perfect for stage III (κ = 0·81; 95% CI, 0·62‐1·00). The intrarater reliability was substantial for all stages and all raters (κ = 0·65; 95% CI, 0·58‐0·72). For stage I it was moderate (κ = 0·50; 95% CI, 0·38‐0·62), for stage II it was substantial (κ = 0·62; 95% CI, 0·51‐0·73) and for stage III it was almost perfect (κ = 0·82; 95% CI, 0·77‐0·87). Hurley stage II and III were less likely to result in discordant staging compared to Hurley stage I (OR 0·47, 95% CI 0·29‐0·77 and OR 0·21, 95% CI 0·12‐0·38 respectively). The mean time spent on staging a photo was 14 seconds.

Conclusions

The Hurley staging is reliable for rapid severity assessment of HS, with a moderate interrater and substantial intrarater reliability for all stages. It is best for assessing Hurley stage III, which is an indication for surgery.

This article is protected by copyright. All rights reserved.

http://bit.ly/2Ajsz4n