Fig. 2

‘On track’ to Patient-Centered Outcome Measurement. To be useful, and provide meaningful information, PCOMs should be grounded in patients and in their daily experience of the rare disease, core concepts, expectations and values. Developing PCOM strategies is an iterative process where qualitative and quantitative patient evidence complement each other to identify those outcomes that matter most to patients. Thus, we always start our journey with the patient (far left of figure) and gain a full understanding of the disease and key concepts (Dark Blue and Brown lines) before proceeding. This may require more than one loop to get correct. Following this, whether one opts for the route to select/adapt an existing outcome measure (Yellow line), or that to develop a novel PCOM (Green line), the anchor remains the same: patients and the conceptual model. Because rare diseases are rare and complex, creativity and pragmatism should prevail. This could include alternate routes to information gathering (Grey line). Ultimately, as we approach our intended destination (Patient-Centered Care), we need to ensure our PCOMs are finalised (Light Blue line), and we are able to begin to build an evidence base for its use