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Psoriasis Disability Index

The Psoriasis Disability Index (PDI) questionnaire is designed for use in adults, ie patients over the age of 16.

It is self-explanatory and can be handed to the patient who is asked to fill it in without the need for a detailed explanation.

Who can use it

This questionnaire can be used in a range of settings by clinicians, pharmaceutical companies, for-profit organisations, students or researchers.

Depending on who you are and what you're using the questionnaire for, you may need to apply for a licence. Please note that there is no charge to use the PDI.

To apply for a licence to use the PDI please directly contact Technology Transfer office at It is not possible to apply using our online licensing system.

Learn more about who can use this questionnaire and how to administer it.

Time for completion

The PDI is usually completed in three or four minutes.

Recall period

The questions are designed to be completed with a four-week recall period. There should be at least four weeks between each use. Very frequent use is not recommended, because you or the patient may remember and be influenced by previous answers or become less careful answering.

Download the questionnaire

Psoriasis Disability Index (PDI) - English version

This questionnaire is designed for patients aged 16 years or over to complete, with a four week recall period.

Different language versions

This zip file contains the questionnaires in different languages, along with the translation certificates. Find out more about our translation and linguistic validation process, and what to do if you'd like to create a new translation.

Psoriasis Disability Index (PDI) - different language versions

Download the questionnaire in several different languages: Arabic, Bosnian, Chinese, Czech, Danish, Filipino, Finnish, French, German, Gujarati, Hindi, Icelandic, Italian, Japanese, Lithuanian, Marathi, Portuguese, Romanian, Serbian, Spanish, Thai, Turkish, Ukranian and Zulu.

How to score it

The score for each question is:

Not at all0
A little1
A lot2
Very much3

If a question is left unanswered, the score = 0.

The Psoriasis Disability Index is calculated by summing the score of each of the 15 questions, resulting in a maximum of 45 and a minimum of 0.

The higher the score, the more quality of life is impaired. The Psoriasis Disability Index can also be expressed as a percentage of the maximum possible score of 45.

Detailed analysis

The Psoriasis Disability Index can be analysed under five headings:

HeadingQuestionsMaximum score
Daily activitiesQuestions 1, 2, 3, 4 and 515
Work or school or alternative questionsQuestion 6, 7 and 89
Personal relationshipsQuestions 9 and 106
LeisureQuestions 11, 12, 13 and 1412
TreatmentQuestion 153


Please note that the Psoriasis Disability Index (PDI) is protected under copyright, so you must not change the format, wording or design of the questionnaire.

This statement must always be reproduced at the end of every copy of the PDI:

© Psoriasis Disability Index. A Y Finlay, S E Kelly 1985



Finlay AY, Kelly SE. Psoriasis: an index of disability. Clin Exper Derm, 1987; 12: 8-11.

Original publication of current version

Finlay AY, Coles EC. The effect of severe psoriasis on the quality of life of 369 patients. Brit J Dermatol, 1995; 132: 236-244. (Gives text of current (second) version)

Other key publications

Contact us

If you have any questions, or you have feedback on our web pages, please get in touch.

General queries and feedback

Dr. Faraz Ali

Dermatology Quality of Life Administrator

Financial, contractual or student enquiries

Joy Hayes

Licencing enquiries

Technology Transfer office

If you need to contact Professor Finlay

Professor Andrew Finlay