Our series of dermatology quality of life questionnaires can be used for clinical, research, commercial or non-commercial use.
Our quality of life questionnaires
For specific information, including the recall period, how to score them, and to download them, please select the relevant questionnaire:
- Psoriasis Disability Index (PDI)
- Cardiff Acne Disability Index (CADI)
- Infants' Dermatitis Quality of Life Index (IDQOL)
Measures for family members
- Family Dermatology Life Quality Index (FDLQI)
- Dermatitis Family Impact Questionnaire (DFI)
- Psoriasis Family Index (PFI-14)
How they can be used
You can use the questionnaires in a range of settings, from routine clinical purposes to research studies.
Depending on who you are and what you're intending to use them for, you may have to apply for a licence, as well as pay a fee.
All of our Quality of Life questionnaires, in any language, may be used by individual patients in order to help their communication with their physicians.
The questionnaires may also be used for routine clinical purposes by clinicians to assist the consultation, evaluation and decision-making process. You can also use them to retrospectively analyse or publish questionnaire data that was collected as part of routine clinical care of your patients,
In these cases, you don't need to apply for a licence to use the questionnaires, and there is no charge. You can just download them from their respective pages.
Assisting with decision-making
Our Quality of Life questionnaires can help inform decision-making. Often a doctor does not have a good insight into the impact that a skin disease has on an individual patient.
If the doctor knew that a patient was experiencing a large impact, then the doctor may alter their management, perhaps being more aggressive with therapy, and in the primary care setting, considering referral to a specialist dermatologist.
Salek S, Roberts A, Finlay AY. The practical reality of using a patient reported outcome measure in a routine dermatology clinic. Dermatology 2007; 215: 315-319.
Katugampola RP, Hongbo Y, Finlay AY. Clinical management decisions are related to the impact of psoriasis on patient-rated quality of life. Br J Dermatol 2005; 152: 1256-1262.
Atwan A, Piguet V, Finlay AY, Francis NA, Ingram JR. Dermatology Life Quality Index (DLQI) as a psoriasis referral triage tool. Br J Dermatol. 2017 Oct;177(4):e136-e137.
If you'd like to use the questionnaires for anything other than routine clinical purposes, then you'll first need to apply for a licence before you can administer them.
Free, non-commercial licences
This is for clinical or academic research studies/projects that:
- are not funded by for-profit organisations, such as a pharmaceutical company
- are funded by national grant bodies, such as the National Institutes of Health (NIH), Medical Research Council, for example
- are carried out by undergraduate and postgraduate students (provided that the project is not externally funded).
This licence is free.
This is defined as any use that is conducted by a for-profit organisation, including pharmaceutical companies. This may include research, marketing or promotional work.
This licence is charged per patient at £14 for the UK and $23 (USD) for the rest of the world. For companies based within the UK and within the European Union, Value Added Tax (VAT) may be payable.
This charge is based upon the total number of patients the questionnaire is administered to. It is not based upon the frequency with which the questionnaires are administered to each individual patient. We'll need to know the exact number (or your close estimate) of patients you are planning to administer the questionnaire to.
Please note: If you're using the Cardiff Acne Disability Index or Psoriasis Disability Index for any commercial purposes, then you won't need to pay a licencing fee, but you'll still need to apply for a licence.
If you would like to retrospectively analyse or publish questionnaire data that was collected as part of a study that was carried out by a commercial for-profit organisation, you must still apply for a commercial licence.
The questionnaires are often used for other purposes, including printed copies for distribution and displaying them on websites. Please contact us directly with as much detail as possible in order for us to advise you of licensing charges, if any.
Apply for a licence
Please fill in our our online form to secure your instantaneous licence. You can also email us. Please note that for all prospective studies (for example, a study with a protocol that requires prior ethical permission), you must apply for a licence in advance.
All correspondence and data is handled in confidence by the University and is never distributed to any third party. Read our data protection policy.
Once the licence has been granted
Once you submit the form, you'll receive an automatic confirmation email to state the licence has been granted. If you haven't received it, please check your junk mail. If in doubt, please contact us.
Once you receive the confirmation email, you may then start using the questionnaires immediately. In due course, we will raise an invoice (using the information you supplied on the form) and send it to you for payment.
Changing the number of subjects
Once the licensing application is completed, you may change the number of subjects at a later date, but please note we do not offer refunds. If you need to add more subjects, a further charge may be applicable.
If you do need to change the number of subjects, please contact us.
How to administer them
Respondents should complete the questionnaire unaided unless there is some specific confusion and they ask for help in understanding a particular question. Nearly all respondents find it easy to complete the questionnaire unaided.
Under no circumstances should respondents be guided to tick an option, such as the ‘Not relevant’ option, as this could lead to bias.
It is also not appropriate to place the score numbers next to the questionnaire answer choices. This is because all of the validation of the questionnaires has taken place without this. Having the numbers present might alter the way in which the respondents answer.
Over the phone
Many of our questionnaires have been administered over the telephone. However, there is no formal validation of this approach.
Use outside validated age ranges
If you use the questionnaires outside of their validated age ranges, the data should be analysed and interpreted with the caveat that it is not formally validated.
Changing the format, wording or design
It is not possible to change the content, wording, or question sequence of the questionnaires. Please remember that any changes without permission would be considered a violation of international copyright laws.
Please note in all instances the copyright statement must be reproduced at the end of the questionnaire. You can find the statement on the individual questionnaire pages.
If you would like to reformat the design to adapt it to your study needs, we would be happy to discuss this with you. However, please note that the copyright for any reformatted design will not change.
We will need to approve of the final format, so please send us copies of the draft version for our review before you use it.
There should not be any pharmaceutical company or other body identifier printed in the new formatting. This means there should not be any text or symbols which might give the incorrect impression that the questionnaire is in some way owned or associated with a particular pharmaceutical company or other body.
As all of our questionnaires are copyright, it is not permitted to add questions to the questionnaires. The questions may also not be copied or used to create an entirely new questionnaire.
The questionnaires can only be administered if you agree to use the exact wording. We only in very exceptional circumstances agree to any change in the wording of our questionnaires.
One major reason why our questionnaires are increasingly used worldwide is that they are always the same. All of their validity and score interpretations are invalidated if any changes are made.
We know that our measures are not perfect and may not be exactly suitable for every circumstance. You may want to consider using a University questionnaire, as well as asking additional separate questions. You may also consider using another resource or developing a new questionnaire to meet your needs.
Many study organisers have often created their own electronic versions of the questionnaires, and our study, along with other others, have shown that if only minimal modifications have been made to the format of the questionnaire, it does not need repeated formal validation.
If you'd like to develop your own electronic versions of our questionnaires, we would facilitate you to do so. You would need formal permission and we would have to review screenshots prior to use.
Our agreement and charges would vary depending on whether your electronic version was for public use or for a specific study. The copyright statement must be reproduced visibly within any electronic format. For more information, please contact us.
Formatting of electronic versions
The guide for use of the paper questionnaires is that if patients miss out the answer to one question, the questionnaire is still valid to be scored.
However, if they miss two or more questions, then the score is invalid. We advise that the same guidance applies to planning any software, i.e. users should be allowed to skip any one question, but not more than one.
Ali, F.M., Johns, N., Finlay, A.Y., Salek, M.S. and Piguet, V. Comparison of the paper-based and electronic versions of the Dermatology Life Quality Index: evidence of equivalence. Br J Dermatol 2017; 177: 1306–1315.
Campbell N, Ali F, Finlay AY, Salek SS. Equivalence of electronic and paper-based patient-reported outcome measures. Qual Life Res 2015; 24: 1949-61.
Translations and linguistic validation
All language versions have full linguistic validation, with a minimum of two parallel independent forward translations, then co-operative agreement, then two independent back translations. There is then a process of further forward and backward translations until we are satisfied that the translation is as accurate as possible.
If you would like to create a new translation, please contact us so we can work with you to create a version that meets our strict validation requirements.
Please do not attempt to undertake a new translation without speaking to us first.
If you'd like to know more about our translation and linguistic validation, or our adjustment of original English text to adapt to local English language use, please contact us.
If you have any questions—or if you have feedback on our web pages—please get in touch.
Dermatology Quality of Life Administrator
Cardiff University School of Medicine
Third floor, Glamorgan House
Heath Park, Cardiff
General queries and feedback
Dr. Faraz Ali
Dermatology Quality of Life Administrator
Financial, contractual or student enquiries
Technology Transfer office
- Telephone:+44 (0)29 2087 6378