Web-based physical activity intervention for people with progressive multiple sclerosis: application of consensus-based intervention development guidance.

We have followed an inclusive, systematic and transparent process to develop the LEAP-MS intervention that enables detailed description of components, context and guiding principles to inform ongoing evaluation. Importantly, PwPMS expressed the need for autonomy in developing physical activity plans. This has been achieved through the embedding of self-management principles in the design and delivery of the LEAP-MS intervention.