Minimum Clinical Important Difference for Resilience Scale Specific to Cancer: A Prospective Analysis

Abstract

Background: The minimum clinical important differences (MCIDs) of resilience instruments in patients with cancer have not been comprehensively described. This study was designed to evaluate MCIDs of 10-item and 25-item resilience scales specific to cancer (RS-SC-10 and RS-SC-25).

Methods: From June 2015 to December 2018, RS-SCs were longitudinally measured in 765 patients with different cancer diagnoses at baseline (T0) and 3 months later (T1). The EORTC QLQ-C30, Connor-Davidson Resilience Scale, Hospital Anxiety and Depression Scale, and Allostatic Load Index were measured concurrently as anchors. Anchor-based methods (linear regression, within-group), distribution-based methods(within-group), and receiver operating characteristic curves (ROCs, within-subject) were performed to evaluate the MCIDs.

Results: 623 of 765 (84.1%) patients had paired RS-SCs scores. Moderate correlations were identified between the change in RS-SCs and change in anchors (r= 0.38-0.44, all p<0.001). Linear regression estimated +8.9 and -6.7 as the MCIDs of RS-SC-25, and +3.4 and -2.5 for RS-SC-10. Distribution-based methods estimated +9.9 and -9.9 as the MCIDs of RS-SC-25, and +4.0 and -4.0 for RS-SC-10. ROC estimated +5.5 and -4.5 as the MCIDs of RS-SC-25, and +2.0 and -1.5 for RS-SC-10.

Conclusions: The most reliable MCID is around 5 points for RS-SC-25 and 2 points for RS-SC-10. RS-SCs are more responsive to the worsening status of resilience in patients with cancer and these estimates could be useful in future resilience-based intervention trials.