Minimal clinically important differences in the EORTC QLQ-C30 and brief pain inventory in patients undergoing re-irradiation for painful bone metastases

Purpose The EORTC QLQ-C30 and the Brief Pain Inventory (BPI) are validated tools for measuring quality of life (QOL) and the impact of pain in patients with advanced cancer. Interpretation of these instrument scores can be challenging and it is difficult to know what numerical changes translate to clinically significant impact in patients’ lives. To address this issue, our study sought to establish the minimal clinically important differences (MCID) for these two instruments in a prospective cohort of patients with advanced cancer and painful bone metastases.