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Developing and testing participant information leaflets that inform and do not cause harm.

An MRC-funded project to improve the way that potential benefits and harms of trial treatments are shared with potential trial participants.

​Patients need to be informed about potential risks of taking part in clinical trials. Our background research suggests that the way harms are communicated can actually increase the risks of the harms occurring. Over half of our sample of 250,000 patients who took placebo pills (like sugar pills) in clinical trials reported some negative side effect (like pain or nausea but also more serious things). The sample of information leaflets provided to patients also found that potential trial benefits were sometimes not mentioned, with potential harms being emphasized.

​The output of the project is a set of Principle for Patient Information Leaflets (PrinciPILs), which will help trialists design information about potential trial risks and benefits in an ethical and balanced way that does not cause unnecessary harm. The principles were developed with a wide range of stakeholders. including patients and public representatives, research ethics committee members, industry representatives, medico-legal experts, psychologists, and trial managers. The results of the development work was published in Trials in 2022.

The principles are intended to support researchers in the development of information about potential trial risks and benefits that is complete, free from ambiguity, well organised and easy to review by the ethics committees. Although this guide is applicable to all clinical trials, the way and extent to which the principles can be implemented will vary from trial to trial depending on the nature of each trial.

​PrinciPILs will also save time because researchers and ethics committees won’t have to reinvent the wheel whenever they are thinking about ways to present potential trial risks and benefits.


The 7 Principles

The PrinciPIL guidance for researchers and ethics committees was developed with stakeholder involvement to further explain and optimize the implementation of the seven principles. Please see 'related documents' for more detailed PDF outputs from the project.

Principle 1

All potential harms of the intervention should be listed. This includes common as well as rare potential harms, and also includes indirect potential harms (for example to conceiving a child, pregnancy, or breastfeeding).​​

​Principle 2

The harms should be separated into serious (life-threatening, causing permanent damage) and less serious (like a mild headache that goes away quickly).

​Principle 3

The fact that not all potential harms are known needs to be clear. Also, sometimes, harms are discovered after the trial begins. As soon as they are discovered, participants need to be told about them.

​Principle 4

All potential benefits of the intervention should be listed.

​Principle 5

Potential benefits and harms of a clinical trial need to be compared with what happens if the participant does not take part in the trial.

Principle 6

Suitable visual representations are recommended where appropriate to describe potential intervention benefits and harms, such as pictograms of faces.

​Principle 7

Information about potential benefits and harms should not be presented apart by one or more pages.