Measuring what matters to rare disease patients - reflections on the work by the IRDiRC taskforce on patient-centered outcome measures

Abstract

Our ability to evaluate outcomes which genuinely reflect patients' unmet needs, hopes and concerns is of pivotal importance. However, much current clinical research and practice falls short of this objective by selecting outcome measures which do not capture patient value to the fullest. In this Opinion, we discuss Patient-Centered Outcomes Measures (PCOMs), which have the potential to systematically incorporate patient perspectives to measure those outcomes that matter most to patients. We argue for greater multi-stakeholder collaboration to develop PCOMs, with rare disease patients and families at the center. Beyond advancing the science of patient input, PCOMs are powerful tools to translate care or observed treatment benefit into an 'interpretable' measure of patient benefit, and thereby help demonstrate clinical effectiveness. We propose mixed methods psychometric research as the best route to deliver fit-for-purpose PCOMs in rare diseases, as this methodology brings together qualitative and quantitative research methods in tandem with the explicit aim to efficiently utilise data from small samples. And, whether one opts to develop a brand-new PCOM or to select or adapt an existing outcome measure for use in a rare disease, the anchors remain the same: patients, their daily experience of the rare disease, their preferences, core concepts and values. Ultimately, existing value frameworks, registries, and outcomes-based contracts largely fall short of consistently measuring the full range of outcomes that matter to patients. We argue that greater use of PCOMs in rare diseases would enable a fast track to Patient-Centered Care.

Keywords: Clinical outcome assessments; Mixed methods research; Patient centricity; Patient-centered outcome measures; Patient-focused drug development (PFDD); Patient-relevant outcomes; Patient-reported outcomes; Rare diseases; Rasch measurement theory.

Fig. 1

PCOMs bring value across all healthcare stakeholders. Evaluating value from the perspective of the patient can bring substantial benefit for all healthcare stakeholders. Because they are grounded in what matters most to patients, PCOMs help translate care and/or observed treatment effect into an ‘interpretable’ measure of patient benefit. By doing so, PCOMs bring value to all healthcare stakeholders involved. PCOMs may be used for several purposes, such as: efficacy endpoints in clinical trials, outcomes measures in registries, guides to treatment choices for daily care, or tools to monitor care delivery

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