Co-design is an effective method for designing software, but implementing it within the clinical setting comes with a set of unique challenges. This makes recruitment and engagement of participants difficult, which has been demonstrated in our study. Our work focused on designing and evaluating a data annotation tool, however, different types of interventions had to be carried out due to poor engagement with the study. We evaluated the effectiveness and feasibility of each of these strategies, their applicability to different stages of co-design research and discussed the barriers to participation present among participants from a clinical background.