DLQI — Dermatology Life Quality Index Calculator

About

The Dermatology Life Quality Index (DLQI) was developed by Finlay and Khan in 1994 at the University of Wales College of Medicine. It is a 10-item self-administered questionnaire covering 6 domains: symptoms and feelings (items 1-2), daily activities (items 3-4), leisure (items 5-6), work and school (item 7), personal relationships (items 8-9), and treatment (item 10). Each item is scored 0-3 (0=not at all, 1=a little, 2=a lot, 3=very much), with a maximum total score of 30. Higher scores indicate greater impairment of quality of life. The DLQI has excellent psychometric properties including test-retest reliability (r=0.99), internal consistency (Cronbach alpha 0.83-0.92), and construct validity demonstrated through correlations with disease severity measures and other quality of life instruments. The DLQI has been validated in over 55 languages and in more than 40 different skin diseases including psoriasis, atopic dermatitis, acne, vitiligo, hidradenitis suppurativa, rosacea, and skin cancer. The DLQI is recommended by the European Academy of Dermatology and Venereology (EADV), the International Psoriasis Council, and the Harmonising Outcome Measures for Eczema (HOME) initiative as the core outcome measure for quality of life in dermatology clinical trials.

Formula

DLQI Total Score = Sum of all 10 item scores (0-3 each). Range: 0-30. Higher scores indicate greater quality of life impairment.

The DLQI total score is calculated by summing the responses to all 10 questions. Each question is scored 0 (not at all), 1 (a little), 2 (a lot), or 3 (very much). The minimum total score is 0 (no impairment of quality of life) and the maximum is 30 (extremely large impairment). If a question is left unanswered (not relevant), it is scored as 0. The DLQI can be analyzed as a total score or by domain: Symptoms and Feelings (items 1-2, max 6), Daily Activities (items 3-4, max 6), Leisure (items 5-6, max 6), Work/School (item 7, max 3), Personal Relationships (items 8-9, max 6), and Treatment (item 10, max 3). The DLQI is categorized into 5 bands: 0-1 no effect on quality of life, 2-5 small effect, 6-10 moderate effect, 11-20 very large effect, and 21-30 extremely large effect. The minimal clinically important difference (MCID) for DLQI varies by condition: psoriasis 3-5 points, atopic dermatitis 4-6 points, acne 3-5 points.

Score Interpretation

The Dermatology Life Quality Index (DLQI) is the most widely used dermatology-specific quality of life instrument in clinical practice and research worldwide. Its clinical significance is supported by over 25 years of validation across more than 40 skin diseases and 55 languages. The DLQI demonstrates excellent psychometric properties including test-retest reliability (r=0.99), internal consistency (Cronbach alpha 0.83-0.92), and construct validity with disease severity measures such as PASI for psoriasis (r=0.42-0.64), SCORAD for atopic dermatitis (r=0.52-0.65), and the acne-specific quality of life instruments. The DLQI is highly responsive to clinical change and is the most commonly used quality of life outcome measure in dermatology clinical trials. The DLQI has been adopted by major regulatory agencies including the FDA and EMA as a patient-reported outcome measure in dermatology drug development. The DLQI is the core outcome measure for quality of life in psoriasis (recommended by the International Psoriasis Council and GRAPPA), atopic dermatitis (recommended by the HOME initiative and EADV), acne, hidradenitis suppurativa, and vitiligo. The MCID for DLQI varies by condition: 3-5 points for psoriasis, 4-6 points for atopic dermatitis, and 3-5 points for acne. The DLQI has also been used to establish treatment response criteria: DLQI 0-1 is considered "treatment goal" for biologic therapy in psoriasis, and a reduction of >=5 points is considered a meaningful response in most conditions. Population norms are available from European general population studies with mean DLQI scores of 0.5-1.5 in healthy individuals.

Reference Ranges