Fig. 1From: Selecting the optimal position of CDK4/6 inhibitors in hormone receptor-positive advanced breast cancer – the SONIA study: study protocol for a randomized controlled trialSchematic overview of study design. Non-steroidal AI: non-steroidal aromatase-inhibitor, either letrozole or anastrozole (at the discretion of the treating physician). CDK4/6 inhibitor: type of CDK4/6 inhibitor according to physician’s choice and reimbursement policiesBack to article page