Three hundred sixty-three patients with chronic pain after total knee replacement were randomized to receive either the STAR care pathway (n=227) or usual care (n=110). The primary outcome of interest was pain severity and pain interference, measured by the Brief Pain Inventory (BPI). Secondary outcomes included the Oxford Knee Score (OKS), PainDETECT, Hospital Anxiety and Depression Scale (HADS), and quality-adjusted life years (QALYs). Outcomes were assessed at one and four years after randomization. Overall, the results revealed that the STAR care pathway showed sustained, though uncertain, clinical benefits and remained cost-effective at four years, with a probability of 0.94 at a £20,000/QALY threshold. The main findings suggest some degree of sustained clinical benefit and clear cost-effectiveness over the long term.