PPI and protocol development A key stage in any systematic review is writing a detailed systematic review protocol. The protocol lays out details of the scope and design of the review, and the methods that will be used to conduct the review. Preferably, a systematic review protocol will be made freely available before the start of the systematic review. This lets people know what you are planning and helps avoid duplication of effort (that is, someone else carrying out the same, or very similar, systematic review). Ideally, there will be PPI at the protocol development stage for the systematic review. It is good practice to have PPI contributors as core members of the review team. They play a key role in helping to plan how to involve additional PPI contributors throughout the review process. The systematic review protocol should describe the planned PPI. In particular, the protocol should give details of: who will be involved, and how these people will be found or recruitedwhen (at what stages) within the review process people will be involved, with a clear aim of the involvement at these stageshow these people will be involved in order to meet the stated aim(s). It is important to consider the key principles for good practice in involving people at the planning stage. The following issues are central to PPI in any research activity, including a systematic review: supportive and positive relationshipsclear and timely communicationthe roles and expectations of everyone involved, which should be discussed and agreed in advance of any involvementskills, knowledge and training (of researchers as well as of the people they involve) neededclarity regarding time commitments and requirements. The project budget and payment for people’s time or expenses, provision of training, and whether ethical approval is required must also be considered. The availability of these resources will influence who you can involve and how. The Cochrane Consumer Network has published a Statement of Principles for Consumer Involvement in Cochrane to guide PPI. It highlights the importance of equity, inclusion and partnership. Communication and organisation are central to successful PPI, and it is important for researchers to consider practical points, such as accessibility (of meetings and materials) and having a clear point of contact for the people who are involved. Choosing who, when and how for your review There is no set formula or single method of involving people in a systematic review. Factors that will influence decisions around the best method for a specific systematic review include the: Topic of the review, and the people who may be affected by the results of the review.Aims of involving people. There may be a very specific aim to be met by involving people, such as informing the review outcomes, or supporting the dissemination of review results.Time available to do the review.Money available to support the review and involvement of people in the review.Expertise of researchers, and their experience of involving people in research.Preferences of the individuals involved.Desire for review findings to be locally, nationally or internationally generalisable. A review may focus on a topic of national importance, and consequently the methods of involvement could focus on gaining involvement across that individual nation. Alternatively, a review may be internationally relevant, so it may be appropriate to gain international views and opinions. Although the research team commonly makes the decisions on the plan, there will ideally be PPI in reaching the plan for the methods of involvement in the review. It is essential to consider the views and perspectives of the individual people who get involved, and to be prepared to be flexible and adaptive to the needs and suggestions of the people involved. For example, although you may have pre-planned 1 large workshop to reach decisions on outcomes important to a review, this format may not be accessible to some people and you may need to adapt your plans. If you are asking people to read or comment on written documents it is important to find out whether any of the people involved have specific requirements to facilitate accessibility, such as larger font sizes or audio versions. When seeking people to get involved, you may consider circulating requests for involvement in a variety of formats to promote accessibility. For example, you could circulate an audio description alongside a written description of the project. Being flexible and responsive, and working in partnership with the people who get involved is important to ensure equity and inclusivity. One review can use a variety of different methods, each of which have a different approach to involvement, with different role classifications, and different levels of involvement. The following sections discuss key things to think about when planning PPI in your systematic review.