Development of a Core Outcome Set for users and funders of lower-limb prosthetic interventions (PI-COS): a step to inform the benefits measured in prosthetic health economic evaluations

Purpose: Little is known about the outcomes that are most important to prosthesis users and funders. A Prosthetic Interventions Core Outcome Set (PI-COS) will help researchers and practitioners measure outcomes that are the most important to prosthesis users and funders. Materials and methods: Prosthesis users and funders rated the importance of 121 International Classification of Functioning, Disability, and Health (ICF) second-level categories using a two-round Delphi survey. A Consensus Meeting using the nominal group technique resolved rating differences between groups. The ICF second-level categories were ranked according to importance and a K-Means Cluster Analysis helped establish the PI-COS. Results: 65 users and 8 funders completed the Delphi surveys, followed by a Consensus Meeting. 26 ICF second-level categories were considered important to prosthesis users and funders and a PI-COS of 14 ICF second-level categories drawn predominantly from five ICF chapters was established: Sensory Functions and Pain (b2), Neuromusculoskeletal and Movement-related Functions (b7), General Tasks and Demands (d2), Mobility (d4), and Products and Technology (e1). Conclusions: The PI-COS describes the outcomes that are most important to prosthesis users and funders. The PI-COS can help focus on the most important outcome measures in clinical practice and research, including future prosthetic health economic evaluations.