Table 3 Comparison of the most commonly cited strategies and design features to maximise recruitment and Booster project examples

Newsletters/mail-outs/flyers (to clinical staff and/or patients)

√ Mail-outs to participants

Regular visits/phone calls to wards/sites/practices

√Visits were made to local GP surgeries, health trainers/champions and one-stop health shops

Posters/information leaflets in clinics/wards/notes

√ Poster produced and displayed in GP surgeries

Inclusion criteria changed/protocol amended

√

Presentations to appropriate groups (e.g., at consults, meetings/community-based physiotherapists)

√ Presentations made to relevant organisations, NHS, local authority on becoming involved

Resource manual for site staff/trained staff in disease area/procedures being investigated/role-play exercises/study day/workshops for recruiters

√ Information provided to research assistants on recruitment

Advertisement/articles in newspapers/journals, radio interviews

√ Trial manager publicity in the local press, newspaper and radio

Presentations at national/international meetings

x

Employed extra staff

√ Administrative assistants hired

Investigators/recruiting staff meetings

√ Monthly meetings between trial manager and research assistants (in addition to monthly trial management group meetings), weekly email updates on recruitment

Training/information videos

x

Incentives for recruiters (e.g., prize draw)

√ Team rewarded at recruitment milestones

Trial material revised/simplified/customised for specific sites

√ Participant information sheet altered due to reflect added secondary recruitment pathways

Visits to centres by PIs/senior members of study group

√ Visits to local GP surgeries and to community venues

Repeated contact by phone/letter to individuals/sites

√ Reminder phone calls to participants

Increased/changed time points when information provided to potential participants

√ Additional mail-out conducted: extra letter to introduce main trial before screening call

Supportive statements from opinion leaders

x Supportive statements from current participants rejected by local research ethics committee

Quality of study team/multi-disciplinary team

√ Multi-disciplinary team from Sheffield Hallam University and University of Sheffield

Involvement of a Clinical Trials Unit

√ University of Sheffield Clinical Trials Unit, main collaborator in the trial

Trial manager

√ Dedicated project manager, appropriate cover arranged at a later date due to maternity leave

Local recruitment co-ordinators

x Centralised recruitment only

Feasibility work

√ Pilot study recruitment conducted

Peer-reviewed study protocol

√ Protocol publication

Simple study design

x Brief intervention and main intervention

Service user input

√ Expert elders attend design

Important research question with support of the clinical community

√ Support of public health, physical activity professionals, GPs and research community

Drug trial/intervention only available in study

√ Motivational interviewing not widely available in community

Appropriately funded

√ HTA funding secured for 3 years