A 15-item short-form version of the 45-item Childhood Atopic Dermatitis Impact Scale (CADIS) is a reliable measure of quality of life in children with atopic dermatitis and their parents, study findings published in the Journal of the European Academy of Dermatology and Venereology suggests.
Parents or primary caregivers of 300 young children in the United States completed the 45-item CADIS, which included 2 dimensions with 5 domains. This included child dimensions of symptoms and activity limitation/behavior and parent dimensions of family/social function, sleep, and emotions. Scores for each item ranged from 0 points (response of “never”) to 4 points (response of “all the time”). Total scores on the CADIS ranged from 0 to 180 points.
A total of 41 parents were asked to complete the CADIS again after 48 hours to examine the test-retest reliability. An exploratory factor analysis was performed on the CADIS, and researchers chose the most representative items to create a short-form version of the instrument. Also, the researchers conducted a confirmatory factor analysis to support the a priori factor structure of the form.
A focus group that included patients, parents, clinicians, methodologists, and industry delegates assessed content validity of the form. Finally, the study investigators examined internal consistency, 48-hour test-retest reliability, construct validity, and responsiveness of a short-form version of the CADIS.
Approximately 90% (n=270) of the 300 enrolled families completed the CADIS and socio-demographic items at baseline. The instrument was completed by 34 of the 41 families after 48 hours for the test-retest reliability assessment. The investigators identified 14 items that fulfilled ≥1 of the proposed criteria for the short-form version of the CADIS. These included 5 items in the symptoms domain, 4 items in the family and social function domain, and 5 items in the emotions domain. An item that related to the child’s sleep was included to improve content validity.
According to confirmatory factor analyses, the instrument demonstrated good model fit. The total scale and the 3 domains in the 15-item short-form (CADIS-SF15) demonstrated good internal consistency and test-retest reliability. Researchers observed correlation with the Severity Scoring of Atopic Dermatitis index as well as subjective measures of pruritus and sleep loss. In addition, the researchers reported significant differences in the total score and all domain scores in the “improving” condition from baseline to 4-week follow-up (P <.001).
A potential limitation of the study was the lack of validation of the short-form CADIS in languages other than English.
The study authors suggest that further research should “focus on testing a shorter recall period since past criticism of CADIS includes that the 4-week recall period was long.”
Disclosure: Several study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.
Gabes M, Chamlin SL, Lai JS, et al. Development of a validated short-form of the Childhood Atopic Dermatitis Impact Scale, the CADIS-SF15 [published online March 16, 2020]. J Eur Acad Dermatol Venereol. doi: 10.1111/jdv.16362