Consent and Participant Information Guidance

Style: What makes a good Participant Information Sheet

In this section we cover general guidance on design and style of a Participant Information Sheet (PIS). We highlight what to consider when your research involves: Adults not able to consent for themselves, Children and Young people and/or Emergency research.

The right style will engage the reader, and help to establish a rapport by fully respecting their perspective and exploring all of the issues that are important to them. If designed well, a PIS is a valuable tool which facilitates effective communication and supports shared decision making.

This guidance is designed to be comprehensive, so not all of it will be relevant to your specific research.

Select the headings below to find out more:

General style guidance for all/most studies:

One size does not fit all

Not all research studies are the same. The information required to enable potential participants to decide if they wish to take part will therefore vary.

Different populations will have different information needs, different levels of understanding of medical terminology and different reading abilities.

The level of detail should be appropriate to the nature and burden of the study.

For example:

  • For questionnaire studies, you can provide sufficient information to enable potential participants to decide if they would like to take part in your research, on the front of the questionnaire. As with all research, you will need to include details of how the participant’s data will be kept safe, who will be the Data Controller and what will happen to any data collected if the participant decides to withdraw at a later date.
  • Whilst

  • The Participant Information Sheet for a Clinical Trial of an Investigational Medicinal Product (CTIMP) will need to be significantly more detailed.

Proportionality: how long should a Participant Information Sheet be?

We advocate a proportionate approach. Consent arrangements must match the study's burden and risk/benefit profiles as well as the complexity of the protocol. A Participant Information Sheet (PIS) should be as long as it needs to be.

If your PIS is too long, there is a risk that potential participants will not read all of it.

Careful layout can make a big difference in how easy a PIS is to read. Adding a contents page may add length, but it can help the reader to locate relevant information.

If the PIS is likely to be lengthy (e.g. more than a few pages) then we suggest splitting your PIS into three sections (e.g. introduction, what's involved and supporting / further information), and using subheadings to break up content further.

Importance of your study title

The study title is part of the explanation of your research: you should never underestimate its importance. When well designed, the title provides a concise summary of your study in language most potential participants would understand.

A consistent study title should appear on all of your documents and be comprehensible to your potential participants.

For interventional studies you could consider the acronym - I.P.O.C. - Intervention, Population, Outcome, Comparator to help you structure a meaningful title.

Invitational style

The Participant Information Sheet (PIS) should be a polite invitation to take part in your research; setting out the possible advantages and disadvantages, placing participation in the context of other options available and describing what potential participants can expect.

You should employ a polite tone throughout your PIS.

Do not use the passive voice

Conversational style in the active voice is found to be more effective than using the passive voice; so use the active voice and the pronoun 'we' throughout.

For example use:

  • 'We would like to invite you to take part in…'
  • 'We intend to collect an additional blood sample when you attend your next clinic…'
  • 'We will post a questionnaire to you…', instead of 'questionnaires will be posted …'
  • '… We will send your samples to colleagues in America for analysis …', instead of '… Samples will be sent to America for analysis …'

Use plain English and avoid jargon

  • Remember who is going to be reading your Participant Information Sheet (PIS).
  • Use short, familiar words and short sentences.
  • Write in simple, non-technical terms that a lay person will easily understand.
  • The language used should be no more difficult to read than information leaflets for medicines or tabloid newspapers.
  • You can use the readability statistics function available in Microsoft Word to calculate a readability score.
  • Potential participants should be able to understand the PIS on the first reading.
  • All of your potential participants should be able to understand your PIS.
  • Remember that some patients might be very familiar with certain technical terms, but not with all medical terminology. Other groups (the newly diagnosed or the general public) may not be familiar with many relevant technical terms.
  • When technical terms have to be included you may wish to provide the lay term first followed by the technical term in brackets. For example:
    • Feeling sick (nausea)
    • Blood clot on your leg (deep vein thrombosis or DVT)
  • When preparing a PIS for an international study, remember that there are terms which have quite specific regional use, for example A&E (UK) instead of ER (USA).

The Cochrane Collaboration suggests that when writing for the general public you should:

  • Limit sentences to no more than approximately 20 words, when possible.
  • Don't introduce more than one idea/point in a sentence. If your next sentence does not directly follow the previous one, start a new paragraph.
  • Avoid potentially misunderstood words (more obscure or commonly misunderstood) or phrases or words with dual or nuanced meanings (e.g. drugs; diet); especially those likely to cause difficulty to those who have English as a second or third language.
  • Hard words are technical words, jargon, not commonly used words, or words that are long or with many syllables.
  • Avoid more than 2 hard words in a sentence unless it is a term that is explained (consider introducing an acronym or shorter term for repeated use).

Instead of using Microsoft Word to calculate readability scores, you could calculate the Flesch Reading Ease score or Fog Score (or an equivalent) and consider how you might improve it. To find out how to calculate the Flesch or Fog Score visit 'Examples & Templates'.


You should use the format best suited to the nature of the information that you wish to give potential participants, and which supports understanding.

In terms of written information, the following are worth considering:

  • Use short headings that stand out.
  • A question and answer format is often effective.
  • Use type as large as possible - size 16 font if you intend to recruit elderly subjects.
  • Leave 'white space' - avoid large sections of unbroken text or long lists.
  • Use bullets for lists.
  • Use non-justified text.
  • Use bold lower case for emphasis.
  • Consider the appropriate page size – it may be that A5, or another paper-size and layout would be more suitable than A4.
  • In some cases, it might be more appropriate to use other media to support the consent process; for example images, diagrams, audio, video or online materials etc. When using alternative formats, you should be mindful that some formats may unintentionally discriminate against people who are not comfortable with or who cannot use such technology.

Using different ways of explaining

There are many ways of describing to potential participants what to expect. You could consider using flow diagrams or pictures if you feel they bring more clarity to the information you are providing. However, consider their use carefully as they do not necessarily help in all cases.

If you are consenting people who cannot read, the Participant Information Sheet may be read to the potential participant as a 'script'. Alternatively, consider using alternative formats to convey the information for example images, diagrams, audio, video or online materials.

Participants' perspective

The purpose of a Participant Information Sheet (PIS) is to set out in writing what taking part in your study will involve for the participant. Including how participation may impact on their treatment and/or their lives and the lives of others close to them.

You must consider the potential participants' perspective. There are issues that might be very important to some people, like:

  • How many times will I have to come to the hospital / research clinic?
  • Will my partner, carer, friend be able to come with me?
  • Will I have to take time off work to take part in this research? Etc.

Consult patients or members of the public to find out the types of issues that might be relevant to your potential participants.

Clarity about expected risks and benefits

In order to facilitate fair decision-making, you must state clearly what the risks and benefits of your study realistically are.

Risk is not easy to describe in a meaningful way. You should give potential participants an honest appraisal of how likely an event is to happen during the course of your study: together with an estimate of the likely impact such an event might have on them.

Potential risks and benefits are estimated from what is currently known about the treatment or intervention used. Potential participants should be made aware of the context in which you are estimating potential risk (e.g. this drug has been given to x people so far and... or this drug is commonly prescribed to people with y and....)

Consulting others from your potential pool of participants (patient groups or other lay people) will help you to describe risk effectively, and identify what is likely to be important to potential participants.

Different groups - different information sheets?

If you intend to recruit two or more different groups of people to your study, you might consider if you need to provide each group with their own Participant Information Sheet (PIS).

In many cases each group may:

  • Have a different set of alternatives available to them;
  • Have different levels of understanding of some technical terms;
  • Understand or perceive risk in a different way;
  • Have very different expectations in terms of the possible benefits of taking part;
  • Have different visual or other accessibility needs etc.

Attempting to write a single PIS that is appropriate to all groups can lead to confusion, lack of clarity and increased length.

Test with relevant people - check you have got it right

You should test your Participant Information Sheet with an appropriate group of people (patient groups or other members of the public) to get help with:

  • Your use of language;
  • Describing risk/benefit and advantages/disadvantages from the potential participants' perspective;
  • Choosing the most appropriate format (including font size, paper size, layout preferences, use of pictures and /or diagrams, audio, video or online materials etc.)

You do not need to obtain NHS Research Ethics Committee (REC) approval to test your consent documents.

Style guidance for specific types of study:

Adults not able to consent for themselves

When approaching legal representatives, consultees, relatives or friends and asking for their consent or advice, you must address the Participant Information Sheet (PIS) to them, as the reader.

The PIS should:

  • Invite them to act as legal representative or consultee, making it clear that they are not obliged to take on this role; and
  • Ask them to consider the information you provide on your study, in light of their relative's / friend's views and needs, rather than their own, so that they can make an informed decision or give informed advice; and
  • In England, Wales and Northern Ireland where advice is sought from a consultee, this should be recorded on a Consultee Declaration form.

If you are unclear on the law and/or terminology used in each UK nation, please visit 'Principles> Adults lacking capacity'.

Children and young people

A Participant Information Sheet (PIS) should be designed for each appropriate age/competence range.

These age ranges may differ depending on the type of study, the condition or the population being approached.

When seeking assent, an information sheet for children and young people should be much shorter and simpler than a PIS designed for obtaining consent.

When seeking assent, it is perhaps more important that the child / young person understands what is involved in general terms rather than attempting to ensure that they fully understand every detail of what is being proposed. For younger potential participants you could consider the careful use of pictures, if you believe they will support understanding.

Consider the child / young person's world. It is important to indicate how the study will affect them at home, school and in his/her social activities.

Studies with little or no intervention and posing minimal risk are likely to need a much shorter information sheet. You will not need to cover all of the issues given in this guidance

If appropriate, the risks of pregnancy and requirements for contraception should be handled sensitively (visit 'Content > PIS > Young people and pregnancy')

Information provided by a series of workshops held with young people from the NIHR Medicines for Children Research Network (MCRN) Young Persons' Advisory Group (YPAG). Further guidance is provided on our 'Resources' page.

Emergency research

The style of Participant Information Sheet (PIS) delivered in an emergency situation should be designed with that specific use in mind.

It should be short, easy to read but contain sufficient detail to enable an informed decision to be made.

You might consider preparing a summary PIS, as well as an accompanying full length PIS.

Participants or those giving consent/advice on their behalf, could consider the full length PIS when the urgency has passed, and when they have time to fully consider the details of what is involved.

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