JCPSLP Vol 17 No 3 2015

findings were consistent with those of the study conducted by VanDam et al. (2012), providing further support for future research to focus on the quality of the HLE in more detail. Despite the current findings, a major limitation of this study is the small number of participants, and the reduced ability to closely control for variables likely to impact the results (Szagun & Stumper, 2012). Though limiting the impact of confounding variables was attempted through participant matching and preliminary assessments, the severity of hearing loss, the age at implantation or amplification, and the nature of early intervention received, were not controlled for in this study. The optimal age at implantation is younger than 12 months, with language delays expected to increase as provision of hearing technology is postponed (Quittner et al., 2013). As shown in Table 1, there was variation in the type of hearing technology provided; however, four out of five D/HH participants received a form of hearing technology before 8 months of age. The NH children were matched to the children who were D/HH by hearing age to control for spoken language experience and language ability. However, the chronological ages of the children varied from 28 months to 51 months. Due to the different stages of language acquisition, parent–child interactions were likely to vary accordingly; thus impacting the results (Greenwood et al., 2010). All D/HH participants received intervention through Telethon Speech and Hearing in conjunction with the provision of hearing technology, though the age at which intervention began and the service delivery model used could not be controlled for. The heterogeneity of the group is reflected in the large ranges observed from the quantity of language measures in particular, and may have contributed to the non-significant results. Nonetheless, this study offers preliminary findings justifying further consideration of the complex relationship between hearing loss and the language environment. Future studies should explore the quantity of language exposure, but also include multiple measures of interaction quality. Altogether, this and future research is underpinned by the objective of improving the language abilities of children who are D/HH. References Ambrose, S., VanDam, M., & Moeller, M. (2011). The role of talk in outcomes of children who are hard of hearing . Retrieved from http://www.lenafoundation.org/pdf/ LENA-Conf-2011/Posters/LENA-Conference- 2011-Sophie-Ambrose-1.pdf Aragon, M., & Yoshinaga-Itano, C. (2012). Using language environment analysis to improve outcomes for children who are deaf or hard of hearing. Seminars in Speech and Language , 33 , 340–353. doi:10.1055/s-0032-1326918 Boons, T., De Raeve, L., Langereis, M., Peeraer, L., Wouters, J., & van Wieringen, A. (2013). Expressive vocabulary, morphology, syntax and narrative skills in profoundly deaf children after early cochlear implantation. Research in Developmental Disabilities , 34 , 2008–2022. doi:10.1016/j.ridd.2013.03.003 Braungart-Rieker, J., Garwood, M., & Stifter, C. (1997). Compliance and non-compliance: the roles of maternal control and child temperament. Journal of Applied Developmental Psychology , 18 , 411–428. Retrieved from https://www.hhdev.psu.edu/ebp/braungart%20 garwood%20and%20stifter%201997.pdf Chouinard, M., & Clark, E. (2003). Adult reformulations of child errors as negative evidence. Journal of

who are NH and their caregivers. The need for this exploration arises from studies describing the lack of quantifiable research in this area (Quittner et al., 2013). The data provides preliminary support for the hypothesis that the quality of interaction in the HLE is influenced by the behaviours and communication abilities of a child that is D/ HH. As predicted, the D/HH group was exposed to an overall less supportive linguistic environment. The results are strengthened by the use of multiple measures of interaction quality, and the large effect sizes produced. The D/HH children and their caregivers initiated communication less often and there were fewer connected interactions. This indicates the children had fewer opportunities to acquire language (Harrigan & Nikolopoulos, 2002). These findings are consistent with literature demonstrating the population has a reduced ability to initiate and continue successful interactions (Morgan et al., 2014; Most et al., 2010). The children who were D/HH also experienced less caregiver expansions; suggesting exposure to language modeling was reduced. As Ruter (2011) discovered, children who are D/HH benefit enormously from caregiver expansions. Therefore these results provide encouragement for future research to explore intervention approaches. Our findings also replicate those of Lederberg and Everhart (2000), who found there were more behavioural directives given to children who were D/HH compared to children who were NH. This pattern was evident, despite the children who were D/HH being older than the children in the NH group. Braungart-Rieker, Garwood and Stifter (1997) stated that child defiance and parental control peaks at approximately two years of age, and steadily decreases across the preschool years. Our results suggest that the parents of children who are D/HH were more controlling and directive; a parenting style cultivated by their child’s aptitudes, though viewed as less supportive of language development (Harrigan & Nikolopoulos, 2002). Two measures did not support the hypothesis of a decreased interaction quality in the D/HH dyad: the number of failed utterances, and the ratio of successful child to parent initiations. The non-significant difference in the number of failed utterances contradicts the literature indicating that decreased intelligibility and communicative responsiveness results in less successful exchanges (Morgan et al., 2014). Harrigan and Nikolopoulos (2002) stated that parents of children who are D/HH are typically the primary communicators, and exhibit increased conversational control. Our results did not support this, instead indicating the parents of children who were D/ HH did not initiate conversation significantly more than their children when compared to the NH child–parent dyad. One explanation for the non-significant results is that the children were receiving intervention through Telethon Speech and Hearing, a facility that engages in auditory verbal therapy. Auditory verbal therapy promotes child verbal communication, parent responsiveness, and developing parental strategies to facilitate communicative success (Chowdry, 2010). This may have increased child initiations and reduced the controlling behaviours of the parents, similar to the outcomes observed after the Hanen program (Harrigan & Nikolopoulos, 2002). Taking this view, the significant results for all other quality measures suggest differences remain despite the intervention received. Differences in the quantity of language exposure between the groups were non-significant for the three measures. The

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JCPSLP Volume 17, Number 3 2015

Journal of Clinical Practice in Speech-Language Pathology