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

OBJECTIVES/HYPOTHESIS

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.

STUDY DESIGN

Prospective cohort questionnaire analysis.

METHODS

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.

RESULTS

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).

CONCLUSIONS

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.

LEVEL OF EVIDENCE

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