Abstract: 【Abstract】 Objective To verify the validity of the atopic dermatitis control tool（ADCT） in assessing disease control in patients with atopic dermatitis（AD）. Methods Based on a cross - sectional study, demographic data, comorbidities and information on disease assessment - related scales such as the ADCT, the pruritus numerical rating scale （NRS）, the patient-oriented eczema measure （POEM）, and the dermatological life quality index （DLQI） were collected from patients with AD at Tianjin Medical University General Hospital from June 2021 to March 2023. The reliability and validity of the ADCT were assessed using these data. The discrimination power of the ADCT total score was evaluated by comparing the differences in the mean ADCT total scores among adjacent POEM/DLQI subgroups based on POEM/DLQI response classifications （POEM: clear or almost absent, mild, moderate, severe, very severe; DLQI: no effect, mild effect, moderate effect, serious effect, very serious effect）. According to the ADCT scores, the AD patients were divided into an uncontrolled AD group （ADCT scores ≥ 7 points） and a controlled AD group （ADCT scores < 7 points）. Differences between the above two groups were analyzed in terms of ADCT item scores, mean pruritus NRS scores, POEM total scores, DLQI total scores, and DLQI dimension scores to evaluate the validity of the ADCT in assessing AD disease control. Results A total of 338 patients with AD were included, comprising 170 （50.30%） males and 168 （49.70%） females, and they were aged 17 to 89 （41.36 ± 17.63） years. Reliability analysis showed that the Cronbach′s α coefficient and split-half reliability coefficient of the ADCT were 0.886 and 0.878 respectively （both > 0.70）, and the test- retest reliability coefficient was 0.977 （> 0.70, P < 0.001）. Content validity analysis showed that the Pearson correlation coefficients between the ADCT item scores and the ADCT total score ranged from 0.753 to 0.852 （all P < 0.001）; confirmatory factor analysis revealed that the Chi-square to degree of freedom ratio （χ2/df） was 2.896 （< 5）, the Tucker-Lewis index was 0.976 （> 0.9）, the comparative fit index was 0.991 （> 0.9）, the standardized root mean square residual was 0.026 （< 0.08）, and the root-mean-square error of approximation was 0.075 （< 0.08）; convergent validity analysis showed that the standardized factor loadings of all observed variables ranged from 0.689 to 0.905 （all > 0.500）, combined reliability coefficient was 0.896 （> 0.700）, and the average extracted variance value was 0.591 （> 0.500）; criterion validity analysis showed that the correlation coefficients of the ADCT total score with other patient - reported outcome measures （the mean pruritus NRS scores, peak pruritus NRS scores, POEM total scores, and DLQI total scores） and DLQI dimension scores ranged from 0.649 to 0.730 and from 0.303 to 0.647, respectively（all P < 0.001）. Analysis of the discrimination power of the ADCT total score showed significant differences in the mean ADCT total scores among adjacent POEM/DLQI subgroups （all P ≤ 0.001）. The uncontrolled AD group （287 cases） showed significantly increased ADCT item scores, mean pruritus NRS score, POEM total score, DLQI total score, and DLQI dimension scores compared with the controlled AD group （51 cases, all P＜0.001）. Conclusion The ADCT exhibited good reliability, validity and discriminability based on the cross-sectional study, and can efficiently and reliably assess disease control in AD patients.

Key words: Dermatitis, atopic, Atopic dermatitis control tool, Reliability, Validity, Disease control, Validation