CM3D: A circular materials Multi-Criteria Decision-Making tool for medical devices

The Circular Economy (CE) is fundamental to reducing healthcare's environmental impact. Moving toward a CE requires closing, narrowing and slowing the flow of materials, parts and products involved in the healthcare system. Materials are critical to medical device circularity. Currently, manufacturers’ material selection processes focus on cost, logistics, manufacturing and regulation. However they neglect the latter phases of the product life-cycle, impeding the move towards circular materials and products. We propose a tool for ‘circular material selection’ in medical devices, using the Multi-Criteria Decision Method (MCDM) to evaluate potential materials. While widely used in other sectors, MCDM is limited in medical devices. The Circular Materials MCDM for Medical Devices (CM3D) addresses this gap and considers the entire product life cycle. Stakeholders informed selection of circular evaluation criteria, with the VIKOR algorithm used to rank material alternatives to identify an ideal ‘circular’ candidate. A case study demonstrates CM3D's practical application in laparoscopic scissor blades and handles. CM3D provides objective assessment of candidate materials and identifies a tungsten carbide coating for scissor blades and stainless steel for handles, aligning with research literature. Future work will apply CM3D to other medical devices and consider wider implementation within multi-component design cycles.