Borg scale: a new method for hypernasality rating.

Purpose: To investigate the reliability in auditory-perceptual assessment of hypernasality of the Borg centiMax scale and the influence of the speech material on the reliability of two scales.
Methods: Four experienced speech-language pathologists rated hypernasality of 80 audio recordings of patients with repaired cleft palate (40 single-word string and 40 sentences) using the 5-point ordinal scale and the Borg centiMax scale. Intra and inter-rater reliability were calculated for both scales and for both types of speech samples. The comparison between the agreement coefficients of the two speech samples was calculated using the Z test and between the scales was calculated by Spearman correlation coefficient, considering as significant p<0.05.
Results: A very high and statistically significant correlation was found between the Borg centiMax scale and the ordinal scale for both speech samples. Intra- and inter-rater reliability was higher for Borg scale as compared to ordinal scale. Good to excellent intra-rater reliability was found for Borg scale for both speech samples. Poor to excellent intra-rater reliability was found for ordinal scale for both stimuli. Higher inter-rater reliability was demonstrated for Borg scale than ordinal scale for both speech samples. There was a significant difference between the single words string and sentences for intra- and inter-rater reliability using Borg scale, and for inter-rater reliability using ordinal scale.
Conclusion: The Borg centiMax scale showed better intra and inter-rater reliability. Additionally, the speech material comprising of single words string showed better reliability in most of the comparisons for both scales.