Cardiff University developed a family of quality-of-life questionnaires that measure how skin disease affects patients and the people around them. They are used in routine clinics, research and clinical trials worldwide. This guide summarises each one: who it is for, how it is scored and how to get it.
The short answer
The Dermatology Life Quality Index (DLQI) is the best known. It is a 10-question measure for adults aged 16 and over, scored 0 to 30, available in more than 140 languages and used in 454 randomised controlled trials across 69 diseases. Children have the CDLQI (ages 4 to 16), infants with eczema the IDQOL, and family members the FDLQI and DFI. The CADI and PDI are specific to acne and psoriasis.
Table of Contents
The questionnaires at a glance
| Questionnaire | For | Questions | Score | Recall |
|---|---|---|---|---|
| Dermatology Life Quality Index (DLQI) | Adults aged 16 and over | 10 | 0-30 | Last 7 days |
| Children's Dermatology Life Quality Index (CDLQI) | Age 4 to 16 (up to 15 years 11 months) | 10 | 0-30 | Last 7 days |
| Family Dermatology Life Quality Index (FDLQI) | Adult family members or partners (16+) of patients of any age with any skin disease | not stated | 0-30 | One month |
| Infants' Dermatitis Quality of Life Index (IDQOL) | Infants with atopic dermatitis under 4 years (up to 3 years 11 months) | not stated | 0-30 | One week |
| Cardiff Acne Disability Index (CADI) | Teenagers and young adults with acne | 5 | 0-15 | Last month |
| Dermatitis Family Impact Questionnaire (DFI) | Adults (16+) with a child up to 15 years 11 months with atopic dermatitis | 10 | 0 | One week |
| Psoriasis Disability Index (PDI) | Adults aged 16 and over | 15 | 0-45 | Four weeks (flag: Cardiff page summary says one week, scoring section says four weeks) |
Cardiff’s full series also includes the Teenager’s Quality of Life (T-QoL), the Psoriasis Family Index (PFI-14), the Family Reported Outcome Measure (FROM-16) for family members across all medical specialities, and the Major Life Changing Decision Profile (MLCDP).
Using them in clinic, study or trial
All of the questionnaires, in any language, can be used by patients and clinicians for routine clinical care without a licence or charge. Students need a free licence requested by their supervisor. Other uses need a licence before the questionnaire is given: Cardiff charges £18 per patient in the UK and $26 elsewhere, while the CADI and PDI need a licence but no fee.
The questionnaires must be used exactly as written. Respondents complete them unaided, score numbers are never printed next to the answers, and one unanswered question is allowed but two or more make the questionnaire invalid. Electronic versions need Cardiff’s permission.
Frequently asked questions
What is the most widely used dermatology quality of life questionnaire?
Which questionnaire should I use for a child?
How do I measure the impact on a patient's family?
Do I need a licence?