Minimal Clinically Important Differences for Measures of Pain, Lung Function, Fatigue, and Functionality in Spinal Cord Injury

Objective. The objective of this study was to determine theminimal clinically important differences (MCIDs) for the numerical pain rating scale (NPRS), peak cough flow (PCF), peak expiratory flow (PEF), fatigue severity scale (FSS), and London chest activities of daily living scale (LCADL) in patients with spinal cord injuries (SCIs) after rehabilitation. Methods. Inpatients with SCI from 2 rehabilitation centers participating in a daily rehabilitation program were recruited. The NPRS, PCF, PEF, FSS, and LCADL were collected at baseline and discharge. The global rating of change scale was performed at discharge. MCIDs were calculated using anchor (linear regression, mean change, and receiver operating characteristic curves) and distribution-based methods (0.5 times the baseline SD, standard error of measurement, 1.96 times standard error of measurement, and minimal detectable change) and pooled using arithmetic weighted mean. Results. Sixty inpatients with SCI (36 males; 54.5 [15.9] years) participated. On average their rehabilitation program lasted 7.3 (1.7) weeks. Pooled MCID estimates were 1.6 points for the NPRS, 69.8 L/min for the PCF, 77.4 L/min for the PEF, 1.1 points for the FSS, and 1.4 points for the LCADL. Conclusion. Established MCIDs for NPRS, PCF, PEF, FSS, and LCADL will help health professionals to interpret results and guide rehabilitation interventions in patients with SCI. Impact. Health professionals and researchers may now use -1.6 points for the NPRS, 69.8 L/min for the PCF, 77.4 L/min for the PEF, 1.1 points for the FSS, and 1.4 points for the LCADL to interpret if changes in pain, cough intensity, expiratory flow, fatigue and activities of daily living after rehabilitation of patients with SCI have been clinically relevant.