Study protocol for the OPTion randomised controlled trial on the effect of prioritising treatment goals among older patients with cancer in a palliative setting

Highlights • Traditionally, general practitioners (GPs) are not involved in cancer-related treatment decisions in a palliative setting. • GPs often have a long relationship with patients offering a unique position to explore patients’ values, especially with older patients. • The OPTion study should provide new information about the effect on self-efficacy of a consultation between GPs and older patients with cancer. • The OPT-conversation (Outcome Prioritisation Tool) specifically concerns preferred treatment goals of the patient. • This study may facilitate greater involvement of GPs in oncology care, and may lead to a more active patient role in treatment decisions.