Auditory-verbal therapy (AVT) is notably one of the most popular approaches to improve communication skills of children with hearing impairment (HI; Kaipa. Int J Pediatric Otorhinolaryngol 2016:86:124 http://bit.ly/2bR8pD4). Focusing on audition as the primary input for learning spoken language without relying on speech reading and gestures, AVT requires children with HI to wear amplification devices on a regular basis. The main differences between AVT and other oral-based rehabilitation approaches are that AVT is tailored to suit the individual needs of each client and that it requires the child's parent or caregiver to be present at each session (Dornan. Volta Rev 2009:109:61). From the time the first report on AVT was published in 1993 (Goldberg. J Am Acad Audiol 1993:4:189 http://bit.ly/2bNfDVu), AVT has been the choice of parents of children with HI for learning spoken language. Like any other treatment approach, it is imperative to evaluate empirical evidence to determine the efficacy of AVT.
A detailed review of studies on AVT outcomes conducted from 1993 to the present reveals a lack of strong evidence supporting the efficacy of this approach (Kaipa, 2016). Ten studies on AVT outcomes in speech and language development report that:
* children with HI receiving AVT can successfully learn spoken language;
* socioeconomic status has no effect on AVT outcomes; and
* hearing-impaired children over 3 years old can catch up with their hearing peers in terms of speech and language.
Of these ten studies, four employed quasi-experimental research design with a control group (Dornan. Volta Rev 2007:107:37; Dornan. Volta Rev 2009:109:61; Dornan. Volta Rev 2010:110:361; Duncan. Volta Rev 1999:101:193). Four other studies employed observational (case-series) design without a control group (Rhoades. Volta Rev 2000:102:5; Hogan. Deaf Educ Int 2008:10:143; Hogan. Deaf Educ Int 2010:12:204; Fairgray. Volta Rev 2010:110:407). The other two studies were retrospective in nature (Diller. Int J Pediatr Otorhinolaryngol 2001:60:219–226; Jackson. Am Ann Deaf 2014:158:539). Only two studies reported AVT outcomes in terms of speech perception. While these two studies suggest that children with HI receiving AVT learn to perceive words effectively even in the presence of background noise, they were non-experimental in nature and employed a case-series design (Sahli. J Int Adv Otol 2011:7:385; Fairgray. Volta Rev 2010:110:407).
Finally, only three survey-based studies have reported the outcomes of AVT with regard to mainstreaming. The findings from these studies suggest that majority of children who received AVT can be mainstreamed in the society (Easterbrooks. Otol Neurotol 2000:21:341; Goldberg. J Am Acad Audiol 2001:12:406; Goldberg, 1993). The survey respondents were composed of participants who were either receiving or had received AVT treatment. Generalizing the results to hearing impaired children who received AVT could be problematic.
The number of studies and the research designs employed by these studies in each of the above three outcome areas are depicted in Figure 1.
Although the findings from the above studies indicate that AVT can help improve communication skills of children with HI, it is important to interpret the study in light of their evidence. Only four quasi-experimental studies with a control group have investigated the success of AVT. Other studies were unable to control multiple extraneous variables such as maturation, randomization, and generalization, thus offered limited to insignificant evidence on AVT's efficacy. While one of the main aims of AVT is to mainstream children with HI, there is negligible evidence to support this.
When it comes to making decisions about the efficacy of an intervention, randomized controlled trials (RCTs) offer the highest level of evidence. Unfortunately, there have been no RCTs evaluating AVT. Despite the challenges of conducting RCTs due to ethical, logistical, and financial reasons, future studies should strive to conduct well-controlled longitudinal studies with diverse participants to more clearly assess the efficacy of the AVT approach.
Kaipa. Int J Pediatric Otorhinolaryngol 2016:86:124.