Evaluating patient-perceived control of atopic dermatitis: design, validation, and scoring of the Atopic Dermatitis Control Tool (ADCT)

Figures & data

Table 1. Final pilot ADCT (ADCT v1) – concepts and response scales.

ADCT v1: Six concepts in the overarching measurement of “AD control”	Anchors of the 5-point response scales
1. Overall severity of symptoms	None ↔ Very severe
2. Frequency of intense episodes of itching	Not at all ↔ Every day
3. Intensity of bother	Not at all ↔ Extremely
4. Frequency of sleep impact	No nights ↔ Every night
5. Intensity of daily activities impact	Not at all ↔ Extremely
6. Intensity of mood or emotions impact	Not at all ↔ Extremely

Table 2. Demographic and clinical characteristics of stage 3 survey participants.

Characteristic	Total (N = 270)
Age (years), mean (SD)	45.53 (16.3)
Median, min to max	45.5, 18–75
Sex, n (%)
Male	60 (22.2)
Female	210 (77.8)
Race/ethnicity, n (%)
White	198 (73.3)
Black/African American	31 (11.5)
Asian	20 (7.4)
Hispanic or Latino	9 (3.3)
Other	12 (4.4)
Highest education level, n (%)
Less than high school	2 (0.7)
High school diploma or equivalent (GED)	48 (17.8)
Some college (or Associate’s degree)	88 (32.6)
College degree (Bachelor’s degree)	77 (28.5)
Some graduate school	14 (5.2)
Professional or advanced degree (e.g. master’s, doctoral)	41 (15.2)
Prefer not to answer	0 (0.0)
How would you rate your eczema? n (%)
Clear	12 (4.4)
Mild	78 (28.9)
Moderate	90 (33.3)
Severe	90 (33.3)
Age of first AD symptoms, n (%)
Younger than 15	113 (41.9)
15–29 years	67 (24.8)
30–49 years	46 (17.0)
50 and older	37 (13.7)
I don’t remember	7 (2.6)
Age diagnosed with AD, n (%)
Younger than 15	92 (34.1)
15–29 years	72 (26.7)
30–49 years	53 (19.6)
50 and older	49 (18.1)
I don’t remember	4 (1.5)

Abbreviations. AD, atopic dermatitis; SD, standard deviation.

Table 3. ADCT total construct validity correlations (N = 270).

	Correlation Coefficient (r) on ADCT Total Score
PRO measure item/domain
POEM
Total score	0.82*
Pruritus NRS
Peak	0.76*
Average	0.79*
DLQI^a
Total	0.82*
Symptoms and feelings	0.83*
Daily activities	0.76*
Leisure	0.72*
Work and school	0.59*
Personal relationships	0.57*
Treatment	0.64*
Skindex-16
Symptoms	0.83*
Emotions	0.79*
Functioning	0.80*
Work or do what you enjoy	0.79*
AD control PGA	0.65*

Abbreviations. AD, atopic dermatitis; ADCT, Atopic Dermatitis Control Tool; DLQI, Dermatology Life Quality Index; NRS, numeric rating scale; PGA, Patient Global Assessment; POEM, Patient-Oriented Eczema Measure.

Note: Spearman correlations were calculated.

* p < .01.

a The sample size is 270 for correlations between the ADCT total and DLQI items with the exception that DLQI Item 7a (“[if no] Problem at work or studying”) has n = 170 due to the skip pattern.

ADCT total is the sum of items 1 through 6 (original scale).

Table 4. ADCT total discriminating ability.

	ADCT total
	N	Mean (SD)	p Value
POEM severity subgroups
None or mild	62	4.18 (2.93)
Moderate	99	9.71 (4.82)
Severe or very severe	109	16.34 (4.77)
ANOVA		Mean difference (95% CI)
None or mild vs. moderate		–5.53 (–6.87, –4.19)	<.0001
None or mild vs. severe or very severe		–12.16 (–13.48, –10.84)	<.0001
Moderate vs. severe or very severe		–6.63 (–7.94, –5.32)	<.0001
Patient-reported AD severity (item S9)
Clear	12	2.08 (1.93)
Mild	78	5.91 (3.75)
Moderate	90	11.02 (4.78)
Severe	90	16.92 (4.89)
ANOVA		Mean difference (95% CI)
Clear vs. mild		–3.83 (–6.03, –1.63)	.0009
Clear vs. moderate		–8.94 (–11.72, –6.16)	<.0001
Clear vs. severe		–14.84 (–17.68, –12.00)	<.0001
Mild vs. moderate		–5.11 (–6.44, –3.79)	<.0001
Mild vs. severe		–11.01 (–12.36, –9.67)	<.0001
Moderate vs. severe		–5.90 (–7.32, –4.48)	<.0001
AD control PGA
Not at all controlled	36	17.97 (4.52)
A little controlled	94	13.02 (4.97)
Moderately controlled	77	11.19 (5.56)
Mostly controlled	54	4.78 (4.21)
Completely controlled	9	1.11 (1.17)
ANOVA		Mean difference (95% CI)
Not at all controlled vs. a little controlled		4.95 (3.07, 6.83)	<.0001
Not at all controlled vs. moderately controlled		6.78 (4.68, 8.88)	<.0001
Not at all controlled vs. mostly controlled		13.19 (11.34, 15.05)	<.0001
Not at all controlled vs. completely controlled		16.86 (13.77, 19.95)	<.0001
A little controlled vs. moderately controlled		1.83 (0.24, 3.42)	.0247
A little controlled vs. mostly controlled		8.24 (6.65, 9.83)	<.0001
A little controlled vs. completely controlled		11.91 (8.60, 15.22)	<.0001
Moderately controlled vs. mostly controlled		6.42 (4.64, 8.19)	<.0001
Moderately controlled vs. completely controlled		10.08 (6.37, 13.80)	<.0001
Mostly controlled vs. completely controlled		3.67 (0.83, 6.51)	.0122
WCW
Yes	13	2.69 (1.38)
No	179	12.44 (6.00)
ANOVA		Mean difference (95% CI)
Yes vs. no		–9.74 (–13.04, –6.45)	<.0001

Abbreviations. AD, atopic dermatitis; ADCT, Atopic Dermatitis Control Tool; ANOVA; analysis of variance; PGA, Patient Global Assessment; POEM, Patient-Oriented Eczema Measure; WCWs, well-controlled weeks.

Table 5. ADCT thresholds based on response patterns: predicting PGA “not in control” subgroup.

Predicting PGA “Not in control”^a
ADCT response “Not in control”	True positive	True negative	False positive	False negative	Sensitivity	Specificity	AUC
Six-item pattern (primary) Item 1 = Moderate OR Item 2 = 3–4 days OR Item 3 = Moderately OR Item 4 = 1 or 2 nights OR Item 5 = Moderate OR Item 6 = Moderate	199	43	20	8	0.96	0.68	0.82
Four-item pattern (alternate) Item 1 = Moderate OR Item 2 = 3–4 days OR Item 3 = Moderately OR Item 4 = 1 or 2 nights	199	43	20	8	0.96	0.68	0.82

Abbreviations. ADCT, Atopic Dermatitis Control Tool; AUC, area under the curve; PGA, Patient Global Assessment.

ADCT cut-off values were selected based on the maximum sensitivity and specificity. The sensitivity is defined as the probability that the ADCT threshold will classify the participant as positive when the participant was not in control based on the PGA (i.e. true positive rate). The specificity is defined as the probability that the ADCT threshold will classify the participant as negative when the participant was in control based on the PGA (i.e. true negative rate).

a Results are from a logistic model predicting the probability of PGA not in control from each response pattern, where not in control included response categories “not at all controlled,” “a little controlled,” and “moderately controlled.”