National scale up of PROM based monitoring after joint replacement in Germany

Patient-reported outcome measures (PROMs) can extend follow-up after joint replacement beyond discharge. Using Germany as a case example, national scalability and its potential impact on cost and health outcomes of a trial-proven PROM-based digital monitoring intervention were assessed. A four-step extrapolation mapped trial tasks and time, removed study-only procedures to derive streamlined delivery models, projected national implementation costs (personnel, licence fees, integration), and modelled population-level effects using trial outcomes and insurance claims. Personnel time decreased from 62 min per patient (trial) to 21 min in a hybrid model that retained limited human touchpoints and to 10 min in an automated model that restricted human involvement to safety-critical interventions, with costs of €158, €133 and €127, respectively. Assuming constant effectiveness, estimated health gains were 0.023-0.025 QALYs per patient with €218-€249 savings, suggesting potential annual national savings of €75-€86 million and a surplus of more than 8200 QALYs. Realised value depends on licence pricing, scalable integration, minimal human touchpoints for engagement and safety, and the transferability of trial effects to streamlined delivery models.