Minimal clinically important difference of voice handicap index-10 in vocal fold paralysis

The Voice Handicap Index-10 (VHI-10) is commonly used to measure patients' perception of vocal handicap. Clinical consensus has previously defined clinically meaningful improvement as a decrease ≥5. This study determines the minimal clinically important difference (MCID) for VHI-10 in patients with unilateral vocal fold paralysis (UVFP) using anchor-based methodology.

Prospective cohort questionnaire analysis.

Two hundred eighty-one UVFP patients completed the VHI-10 on two consecutive visits (within 3 months). At the follow-up visit, patients answered an 11-point Global Rating of Change Questionnaire (GRCQ) scored from -5 to +5. Relationship between the GRCQ and change in VHI-10 was quantified using analysis of variance, and MCID for the VHI-10 was determined using receiver operating characteristic (ROC) curve analysis.

Overall mean VHI-10 change was -3.71 (standard deviation [SD] = 8.89) and mean GRCQ was 1.37 (SD = 2.51). Average interval between measurements was 1.73 months (SD = 0.83). Mean changes in VHI-10 scores were -7.45, -0.53, and +4.40 for patients whose GRCQ scores indicated improvement, no change, and worsening, respectively. Differences between mean scores were statistically significant (P < .001). Area under the ROC curve was 0.80, demonstrating the classification accuracy of VHI-10 change scores. A VHI-10 change of -4 was determined to be the optimal threshold that discriminated between improvement and no improvement (sensitivity and specificity 0.62 and 0.88, respectively).

The MCID for improvement in VHI-10 in UVFP patients is a decrease of 4. This information improves understanding of patients' response to treatment and allows comparison between different treatments. Future research should determine MCID for VHI-10 across all voice disorders.

4. Laryngoscope, 128:1419-1424, 2018.