Dialectal and gender differences in nasalance scores in a Japanese population.

OBJECTIVES The aim of the present study was to determine whether there are dialectal and gender-related differences in nasalance scores for normal Japanese speakers. MATERIALS Sixty-eight volunteers consisting of 31 males (age 23.8+/-2.0) and 37 females (age 23.2+/-2.5) were included in this study. They had no diseases affecting speech, and lived in the same region until high school from birth. According to geography, they were divided into four regional groups: Chugoku region, Kinki region, Shikoku region, and other regions. METHODS A kitsutsuki passage, which consisted of Japanese non-nasal consonants and vowels, and the Japanese vowels /a/, /i/, /u/, /e/ and /o/, were read three times, and the mean nasalance scores were then obtained with a Nasometer II 6400. The scores of males and females were compared statistically by means of a Student's t-test. The differences among the three regions, Chugoku, Kinki and Shikoku region, were also investigated by means of a one-way analysis of variance (ANOVA). RESULTS AND CONCLUSION For all sentences and vowels, the nasalance scores were significantly different between males and females. The one-way ANOVA showed that there were no significant differences among the three regions in both males and females.