As the elderly population increases in an aging society, the need for hearing aids also increases accordingly. Unfortunately, hearing aid fitting in Japan is not always provided by a qualified specialist. A comparative multi-country study on hearing loss and hearing aid usage has demonstrated that satisfaction with hearing aids in Japan is approximately half the levels recorded in other countries, which may owe to the non-regulated quality of hearing aid fitting provided by non-qualified specialists. We retrospectively investigated user satisfaction with the hearing aids that were fitted in our hospital. The results revealed that approximately 80% of the patients who used the hearing aids fitted in our hospital felt satisfaction with them. The obtained rate of satisfied patients was superior to that for all Japan and was equal to the rates in the other countries as reported in previous comparative multi-country studies. Furthermore, our result regarding the degree of satisfaction agreed with the findings of previous studies reported by other hospitals in Japan. To improve the quality of hearing aid fitting, contributions are necessary from qualified specialists such as otolaryngologists and speech-language-hearing therapists.

Few comprehensive studies have been performed on the syntactic development of Japanese native language children around 2 years old, and the process has not yet been clarified. The participants in this study were 3 girls for whom we were able to obtain consent from their parents for continual observation. The purpose of this study was to observe how particles are used in mother-infant interaction from 2 years and 0 months to 2 years and 6 months and to analyze whether or not individual differences and commonalities exist between three typically developing children. Some particles were in evidence in all 3 children at the age of 2 years and 0 months. The particles newly acquired during the observation period were of many kinds, including final particles, case particles, connecting particles, and binding particles. The building particles "wa" and "mo" were obtained early on, while the case particle "ga" was produced several months later than other particles. In addition, there were large individual differences; the number and types of particles were fewer and development was slower in children with delayed two-word utterances. These results suggest that observation of the types and frequency of use of particles in spontaneous speech after 2 years old can be an important indicator for subsequent development of syntax.

Few studies have been performed on the relationship between acquisition of expressive vocabulary and development of cognition and play in children with intellectual development disorder at home. In the present study, the author conducted case studies on early acquisition of expressive vocabulary and construction of a vocabulary area in 10 preschool children with intellectual development disorder, focusing on the time to attain over 200 expressive words. The author asked the mothers of the children to answer a questionnaire on their child's play and cognitive development at home. To understand the children's language development, the mothers filled out the Japanese MacArthur Communicative Development Inventory (CDI). The author found that in the phase of 50 to 200 words of expressive vocabulary, the development of cognition and play at home was gradual and unstable, as some items of the questionnaire that reflected cognitive and play development at home were rated as absent or transitioning from appeared to absent. The spread of vocabulary areas in the CDI corresponded to increased amounts of expressive vocabulary, and expressive vocabulary began to be seen in new areas such as action words from the 50-word phase. In the 50-100-word range of expressive vocabulary phase, individual differences began to be seen in the spread of the vocabulary area, suggesting a relationship with development of cognition and play at home reflecting the strengths of the child.

We examined vocal fatigue with wearing of face masks by healthcare workers. The subjects were 459 healthcare workers (male: 100, female: 359) working at Matsuyama Rehabilitation Hospital. We conducted a questionnaire (length of time wearing a face mask, time using voice, throat symptoms, sense of fatigue/stress), and used VFI (Vocal Fatigue Index) and VHI-10 as the examination parameters. The results showed that there were many respondents (271, 80.8%) who expressed a feeling of oppression, but relatively few (82, 17.9%) had throat symptoms. In terms of VFI, we found that females, respondents in their 50s, and nursing care staff indicated high values while Factor R (R: rest) scored high among all factors. The cutoff value for VFI was 24.6%. In the VHI-10, males and respondents in their 70s posted higher values, while lower values were scored by speech therapists. In terms of aspects, the functional aspect recorded higher values and the emotional aspect scored lower. There was a significant difference in VFI scores with and without fatigue.

The purpose of the present study was to verify the usefulness of a Japanese version of the Erickson S-24, a questionnaire that measures communication attitudes, for assessing stuttering. The study investigated the standardized S-24 scores for people who do not stutter, and also collected scores from previous studies for people who stutter and those who do not. The participants were 413 people who do not stutter, aged between 20 and 69. The mean and standard deviations of their S-24 scores were 12.62 and 4.90, respectively. There were no significant differences in scores by age group or gender. High internal consistency and test-retest reliability were found. For the previous studies in Japan, the mean and standard deviation scores were 17.57 and 4.62, respectively, for people who stutter, and 12.96 and 4.89, respectively, for those who do not stutter, indicating significant differences in effect. These results suggest that the S-24 has high reliability and construct validity, and would be useful for assessing stuttering.