(HealthDay)—A difference of 6 on the Voice Handicap Index-10 (VHI-10) total score may represent a minimal important difference (MID) for patients with voice disorders, according to a study published online Sept. 28 in JAMA Otolaryngology—Head & Neck Surgery.

Stephanie Misono, M.D., M.P.H., from the University of Minnesota in Minneapolis, and colleagues used an anchor-based approach to estimate MID in the VHI-10 total in a . A volunteer sample of adult patients visiting a voice clinic, with a variety of voice disorders, completed the VHI-10 in conjunction with a global rating of change at baseline and two weeks later. An MID was identified using an anchor-based approach.

The researchers found that the mean change in VHI-10 score was 1 for patients reporting no change on the global change score; the mean change was also 1 for those reporting a small change. The mean change in VHI-10 was 6 for those reporting a moderate change in symptoms, while those reporting a large change had a mean change in score of 9. There was a correlation of 0.32 between the global change score and change in VHI-10 score.

"Given the lack of differentiation between small and no change and the modest correlation between the global change score and change in the VHI-10 score, additional studies are needed," the authors write.