Voice outcome measures: correlations with patients' assessment of their condition and the effectiveness of voice therapy.

This study investigated correlations between voice outcome measures. Participants' ratings from the Voice Handicap Index (VHI) and a self-rating scale of vocal impairment (SRS) were compared with perceptual assessment (using GRBAS) and acoustic analysis of sustained vowels and connected speech. The measures were taken from ten female participants, pre- and post-therapy. Correlations between pre-therapy measures were generally stronger than between post-therapy measures; and parameters significantly related to participants' assessment of their condition differed from those related to participants' perceptions of improvement. Within the framework of the importance of multidimensional outcome measures, it is recognized that interdimensional relationships need not necessarily exist. For certain parameters, this appeared to be the case.