Adaptation of a Rehabilitation Program for Prosody and Its Application on Egyptian Hearing Impaired Children

Prosody is the melody and rhythm of speech, it is used to refer to the supra segmental aspects of speech including pitch, loudness and duration. Variations in these features achieve different prosodic functions and are perceived by the listener as meaningful changes. The role of prosody in language acquisition and effective communication is documented in research. Nevertheless, prosodic intervention in children with hearing impairment received less attention compared to other speech and language areas.

The aim of this study is to adapt the "prosody treatment program", an evidence based rehabilitation program, and to detect the efficacy of its activities in improving the prosodic skills of Egyptian hearing impaired children.

The "prosody treatment program" is an evidence-based practice targeting receptive and expressive prosodic skills in addition to speech production, intelligibility, pragmatics and phonology. The program is applied using a systematic approach of providing cues following the principles adapted from dynamic temporal and tactile cueing (DTTC) for speech motor learning to help accelerate the child's learning of the prosodic skills targeted in this program. The program was translated to Arabic and adapted to be suitable for the Egyptian children.

Prosody has an important role in several areas of communicative functions including : grammatical, pragmatic, affective and/or indexical functions. Prosodic abnormalities extend across a wide range of communication disorders. Intact functioning auditory system has a fundamental role in language acquisition and development. Children receive the speech of others as a source of linguistic input which is considered their target and they gradually modify their productions using their own auditory feedback to reach the target utterance.

Hearing impairment early in life deprives the child of the source of their linguistic input affecting various aspects of speech and language development. Speech production of the hearing impaired is characterized by various segmental and suprasegmental errors.

Case studies show that interventions targeting prosody can modify prosody in young children with speech and language impairments. Multiple problems of prosody , language, speech and voice are found in individuals with prosodic impairments ,therefore it is challenging to develop treatment protocols addressing prosody .There are only few published interventions targeting prosody .

Due to lack of well structured comprehensive Arabic programs targeting prosody , this work was dedicated towards adaptation of "prosody treatment program" a remediation program targeting receptive and expressive prosodic skills and its application on hearing impaired children .The proposed program targets two levels: preschool and school aged children.

The aim of this work was to adapt the "prosody treatment program" program and apply its activities in cases of hearing impairment to detect its efficacy in improvement of prosodic skills in Egyptian hearing impaired children fitted with hearing aids or cochlear implant devices.

This study was conducted on 55 children with hearing impairment attending the Unit of Phoniatrics , in the outpatient clinic of Alexandria Main University hospital. Sample size was calculated using two proportions power analysis in NCSS and PASS program a minimum sample size required to detect the efficacy of the "prosody treatment program" in improvement of prosodic skills of Egyptian hearing impaired children and to detect a difference of 0.5 that achieve 80% power with a target significance level at 5%.

The proposed program is based on " prosody treatment program", a program targeting receptive and expressive prosodic skills. It includes activities targeting loudness , word stress ,syllable stress ,pitch ,question inflections ,emotions ,sarcasm ,rhythm ,chunking, and speaking rate . The program was adapted in order to be appropriate to the Arabic language and to the Egyptian children. The program was applied using a systematic approach of providing cues to help accelerate the child's learning of the prosodic skills targeted in the program. Cues are adapted from the Dynamic Temporal and Tactile Cueing (DTTC) for Speech Motor Learning hierarchy. It aims at improving motor planning, and programming speech processing as speech and language acquisition progresses.

The program is divided into two sections according to the age into preschool section and school age section.

A pilot study was conducted on 8 cases with hearing impairment attending the phoniatrics unit to check the suitability of the rehabilitation program and modify the needed items.

All subjects met the specified inclusion and exclusion criteria and were assessed by the specified protocol of assessment to evaluate prosodic skills, language skills and cognitive abilities before and after intervention.

Data were analyzed using IBM SPSS software package version 20.0. (Armonk, NY: IBM Corp). Qualitative data were described using number and percent. Chi square test was used for comparison of qualitative variables in two groups, Fisher exact test was used to compare qualitative variables when 50% of cell value was less than 5. McNemar test was used to compare nominal variables before and after intervention. The Kolmogorov-Smirnov test was used to verify the normality of distribution. Quantitative data were described using mean, standard deviation and IQR. Test of significance used included different tests. t test to compare between different means. Mann Whitney U test to compare non normally distributed quantitative variables in two different groups. Paired t test for comparison of normally distributed variables in matched pairs. Wilcoxon signed rank test for pre-post comparison in non-normally distributed quantitative variables. Kappa coefficient was used to assess level of agreement between two raters. Significance of the obtained results was judged at the 5% level.

Eligibility Criteria:
Inclusion Criteria:

* Hearing impaired children of both sexes, in the preschool age (from 3 to 6 years), and school age (6 to 18 years).
* Children using auditory verbal communication.
* Children with moderately severe or severe up to profound sensorineural hearing loss in unaided conditions, fitted with hearing aids or cochlear implant devices with good benefit (aided hearing threshold less than 40 dB across all frequencies).

Exclusion Criteria:

* Children with intellectual disability.
* Children with brain damage.
* Children with additional sensory deprivation (impaired vision).
* Psychiatric problems (example; ASD).
* Motor speech disorders (example: apraxia, dysarthria).