Table 1 Interview topic guide

About the interviewee:

 Role/responsibilities, including clinical and other interests

Contact with TYA patients

 Experiences of providing care to TYA

 If/how providing care to older adults (or children) is different

Involvement with trials:

 Understanding of the term

 Experience of trials work

 Reasons for doing trials

 Views on costs and benefits of trials (to current and future patients, professionals, and organisations)

 Decision-making about whether to open any specific trial locally

 Processes for opening a trial locally

 Barriers and facilitators to timely opening of trials

 Scope for improving processes

Recruiting TYA (and other) patients to trials open locally

 Experience of recruiting TYA (and other) patients

 Processes for identifying eligible patients

 Deciding whether or not to approach individual patients

 Who/what is involved in recruitment

 Issues, concerns, and/or challenges specific to TYA (in general and/or sub-groups)

Referring TYA (and other) patients to trials open elsewhere

 Experience of referring TYA (and other) patients

 Processes for identifying eligible patients

 Deciding whether or not to approach individual patients

 Who/what is involved in referral

 Issues, concerns and/or challenges associated with referral to trials open elsewhere

 Issues, concerns and/or challenges specific to referring TYA to trials open elsewhere

Increasing TYA participation in trials

 Explanations for variation (in levels of participation) between services and sub-specialisms

 How to promote trial participation by this age group

Other issues or comments

 Changes in context and/or trials

 Emergent issues