Validation of the Atopic Dermatitis Control Tool (ADCT©) using a longitudinal survey of biologic-treated patients with atopic dermatitis

Table 2 Cronbach’s α for internal consistency reliability of ADCT

	Baseline (n = 1010)	Month 1 (n = 538)	Month 2 (n = 458)	Month 3 (n = 372)	Month 6 (n = 206)
Overall internal consistency	0.90	0.93	0.94	0.94	0.95
Item-to-total correlation
Overall severity of AD symptoms	0.74	0.79	0.81	0.81	0.84
Days with intense episodes of itching	0.68	0.76	0.79	0.81	0.79
Intensity of bothersomeness	0.81	0.85	0.89	0.89	0.88
Problem with sleep	0.68	0.75	0.73	0.78	0.83
Impact on daily activities	0.76	0.82	0.82	0.84	0.82
Impact on mood or emotions	0.71	0.79	0.82	0.84	0.86

ISSN: 1471-5945