A New Scale for Assessing the Severity of Uncomplicated Diaper Dermatitis in Infants: Development and Validation

One methodologic challenge in conducting research relating to diaper dermatitis (DD) is the absence of a reliable, objective, validated scale for assessing severity. The aim of this study was to develop and validate such a scale.

Scale development was based on experience of DD assessment and clinical and photographic data collected during the early stages of a randomized controlled trial of two DD treatments. The severity score is the sum of scores of four domains: severity of erythema and irritation, area with any DD, papules or pustules, and open skin. Possible scores range from 0 (clear skin) to 6 (extensive DD including intense erythema, papules or pustules, and open skin with damage to the dermis). Assessors used the scale to attribute severity scores using high-definition photographs of infants and babies with DD. Interrater reliability (IRR), internal consistency, and test-retest reliability were considered using intraclass correlation coefficients (ICCs), Cronbach's α, and Cohen κ statistics.

IRR was very good between assessors familiar with the scale (ICC = 0.949, p < 0.001) and between assessors unfamiliar with the scale (ICC = 0.850, p < 0.001). Test-retest reliability at 2 weeks was good (κ = 0.603, p < 0.001). Cronbach's α for internal consistency was 0.702. Collation of photographs according to severity score revealed a visible continuum of DD severity, suggesting good construct validity.

The newly developed scale appears to be easy to use, reliable, and effective in detecting increasing or lessening DD severity.