Table 3 Key study points and learning opportunities to enhance cancer trial communication and recruitment during uncertain times

• The pandemic introduced additional uncertainties in the context of PETReA, which altered practitioner and patient treatment preferences despite an absence of clear evidence about how COVID-19 influenced the risks of trial treatments.

• Patients reported less face-to-face contact and fewer clinical appointments during COVID-19. They also described reduced access to sources of trusted information (e.g. research nurse contact) and uncertainty about the trial pathway following randomisation, compared to patients randomised before COVID-19.

• Patients were worried about contracting COVID-19 when attending hospital clinics during the first wave. Patients’ risk perceptions of COVID-19 varied depending on the nature of their work, where they lived, who they lived with, and their behavioural strategies to avoid COVID-19 transmission.

• We did not see pronounced changes in patient engagement with PETReA during COVID-19. Patients were clear that they were keeping their participation in the trial under review, but they did not disengage. The uncertainty surrounding COVID-19 led practitioners to emphasise that it was ok for patients to change their mind and withdraw from the trial, which helped patients continue with the trial during uncertain times.

• Patients found the discussions with practitioners about the trial arm risks and benefits more in-depth and collaborative during COVID-19. Patients valued this and indicated that it supported them to continue with randomisation.