Developmental outcomes of early-identified children who are hard of hearing at 12 to 18 months of age
Introduction
Over the past decade, universal newborn hearing screening (UNHS), improved screening techniques, and the committed efforts of Early Hearing Detection and Intervention (EHDI) programs have helped to lower the age at which children with congenital hearing loss are identified. Before the implementation of UNHS, the average age of identification of congenital childhood hearing loss in the United States was 2 to 3 years [1]. However, children with mild to moderate hearing loss frequently were not identified until they entered school [2]. As a result of the widespread adoption of EHDI programs across the country, children with hearing loss of varying degrees are now being identified, on average, by 3 months of age [3].
Although it is well documented that children with congenital hearing loss are at risk for speech–language delays, poor academic achievement, literacy delays, and psychosocial difficulties in comparison to their peers with normal hearing [4], a substantial body of research evidence indicates that early detection and intervention can help reduce negative outcomes for these children [5]. Much of the outcomes research on children with hearing loss, however, has focused on children with severe and profound hearing loss (> 70 dB HL) and, more recently, children with cochlear implants. Significantly less attention has been given to developmental outcomes for children who are hard of hearing (i.e., those children with better-ear pure-tone averages between 25 and 79 dB HL, who typically receive benefit from hearing aids and do not use cochlear implants). Of the few studies that have investigated outcomes for children who are hard of hearing, most have involved school-aged children whose hearing losses were identified after 2 years of age with hearing aids fitted later [6], [7]. Consequently, we know relatively little about the developmental outcomes and intervention needs for very young children who are hard of hearing, especially those identified within the first few months of age.
Prior to the implementation of EHDI programs, most studies reported adverse language outcomes for children who are hard of hearing, especially in the areas of phonology, morphology, vocabulary, and syntax [8]. Though relatively limited in scope, more recent research suggests that young children with mild to moderate hearing loss, who are identified early, amplified by 3 months of age, and enrolled early in early intervention by 6 months of age, may not show language delays to the same extent as do children who are later identified (> 6 months of age) [9].
Given the well documented associations between language delays and behavioral, social, and emotional difficulties in the general population of hearing children [10], it is not surprising that children with hearing loss have been found to evidence in general more behavioral and social problems than typical hearing peers. In particular, children with severe and profound hearing loss have been noted to exhibit problems with externalizing and internalizing behaviors, attention, emotional regulation, and social understanding [11]. Although there is some evidence that school-aged children with mild and unilateral hearing loss also are prone to elevated rates of emotional and behavior difficulties [6], we do not know whether younger children who have been identified through EDHI programs and provided early intervention services exhibit similar types and frequencies of psychosocial problems.
Over the years, research has linked a variety of child and parent factors with developmental outcomes of children with severe and profound hearing loss. These factors include severity of hearing loss, gender, presence of additional disabilities, maternal education, ethnicity, and family socioeconomic status (SES). Whether these particular variables contribute significantly to early developmental outcomes of children who are hard of hearing is not well known. Further, the extent to which early intervention services may help moderate developmental risks associated with certain child and parent factors (e.g., severity of hearing loss, low SES) has not been adequately examined for children who are hard of hearing.
Recently there has been an increased interest in examining the influences of parenting factors for children with hearing loss [12], [13]. This new line of investigation is not surprising, as an extensive body of literature has shown strong relationships between maternal self-efficacy, parenting stress, and developmental outcomes for children with normal hearing. Specifically, higher maternal self-efficacy and lower parenting stress have been linked with more positive child outcomes, including age-appropriate language development, better academic achievement, and healthier social–emotional adjustment [14].
Surprisingly few studies have examined the relationship between self-efficacy of mothers of young children with hearing loss and children's developmental outcomes. In a study by DesJardin and Eisenberg [13], mothers of preschool children with cochlear implants who felt more knowledgeable and efficacious in developing their children's language skills provided their children with higher-level language strategies, including parallel talk and open-ending questioning. Moreover, these facilitative language techniques were positively associated with children's spoken language skills. In a follow-up study, DesJardin [15] found mothers of children with severe to profound hearing loss who used hearing aids to have lower self-ratings of self-efficacy and involvement in their child's sensory device use and speech–language development than mothers of children with cochlear implants. Neither of these studies, however, included children with milder degrees of hearing loss.
Although parenting stress among mothers of children with hearing loss has received considerable attention, research findings have been inconsistent. Some studies report significantly higher levels of stress for parents of children who are deaf or hard of hearing than for parents of children with normal hearing [16], and other studies reporting no differences between groups [17]. These contradictory findings have been attributed to a variety of factors, including differences in study sample size, child age, degree of hearing loss, and assessment instruments used to measure parenting stress. However, Meinzen-Derr, Yim, Choo, Buyniski, and Willey [18] suggested that the types of parenting stressors experienced by parents of children with hearing loss may be different than those experienced by parents of children with normal hearing and, importantly, that these parental stressors evolve over time. Moreover, they asserted that in order to provide appropriate support services to promote optimal child development, it is imperative we have a better understanding of the specific concerns that burden parents of children with hearing loss across the lifespan. Currently, we have limited knowledge regarding the parenting stress that may be experienced by mothers of very young, early-identified children who are hard of hearing.
The primary aim of this study was to examine the early developmental outcomes, including language skills, social–emotional functioning, and adaptive behavior, for very young children who are hard of hearing compared with those for children of similar age with normal hearing. A secondary aim was to explore the associations between child, maternal, and parenting factors, and developmental outcomes for children 12 to 18 months of age who are hard of hearing.
Section snippets
Study population
As part of a longitudinal prospective outcome study, a culturally diverse cohort of 28 children ages 12 to 18 months with bilateral mild to severe hearing loss and their parents were identified for inclusion in our investigation. Forty-two children of similar age with normal hearing and their parents were enrolled for comparison purposes. All children and their parents were recruited through two prominent pediatric audiology clinics located in Los Angeles and Indianapolis. Research procedures
Statistical analysis
Descriptive statistics were used to characterize the study sample and performance on the developmental and functional outcome measures. Bivariate analysis, chi-square (χ2), Mann–Whitney U test, and analysis of variance (ANOVA) were used to examine differences between groups. Relationships between child, parent, and parenting variables and outcome measures were examined using either Pearson's r or Spearman's correlation (rho), as appropriate.
Child and parent characteristics
The two groups of children were similar on age, gender, race, and ethnicity (Table 1). Although the study sample was predominantly Caucasian (hard of hearing = 79%; normal hearing = 81%), the sample was diversified relative to ethnicity with 32% of the children with hearing loss and 22% of the children with normal hearing identified as Hispanic. All of the mothers indicated that they spoke primarily English with their child. However, parent questionnaires revealed that all the Hispanic children,
Discussion
With the implementation of UNHS, infants with milder degrees of hearing loss are being identified soon after birth in greater numbers than in the past. As a result, professionals are now faced with the challenge of providing appropriate and effective intervention to a population of children and their families about which relatively little is known. The present study represents one of the first comprehensive investigations of developmental outcomes specifically targeting young children who are
Summary and conclusions
This study indicates that very young children with mild to severe hearing loss, who are identified early and provided prompt intervention that includes amplification, can demonstrate age-appropriate development in multiple domains. Results also underscore the significance of parent-related factors, especially perceived maternal self-efficacy, in influencing positive developmental outcomes for these children early in life. Although our findings offer a more optimistic picture with respect to
Conflict of interest statement
The authors declare no potential conflict of interest with respect to the research, authorship, and/or publication of this article.
Acknowledgments
Support for this research was provided by the National Institute on Deafness and Other Communication Disorders (NIDCD) of the National Institutes of Health grant R01 DC009561 and R01 DC009561-01S1.
We would like to express our sincere appreciation to the parents and their young children who gave their time to participate in this study. We also thank Alice S. Carter for her generous support and advice, and Allison Ditmars and Heidi Neuburger for their valued assistance.
References (32)
- et al.
Listen up: children with early identified hearing loss achieve age-appropriate speech/language outcomes by 3 years-of-age
Int J Pediatr Otorhinolaryngol
(2012) - et al.
Potential roles of parental self-efficacy in parent and child adjustment: a review
Clin Psychol Rev
(2005) - et al.
Pediatric hearing impairment caregiver experience: impact of duration of hearing loss on parental stress
Int J Pediatr Otorhinolaryngol
(2008) - et al.
The effects of maternal stress and child language ability on behavior outcomes of children with congenital hearing loss at 18–24 months
Early Hum Dev
(2011) The current status of EHDI programs in the United States
Ment Retard Dev Disabil Res Rev
(2008)- et al.
Age of suspicion, identification and interaction for infants with hearing loss: a national study
Ear Hear
(1999) - et al.
Newborn hearing screening speeds diagnosis and access to intervention by 20–25 months
JAAA
(2009) Current state of knowledge: psychosocial development in children with hearing impairment
Ear Hear
(2007)Early intervention and language development in children who are deaf and hard of hearing
Pediatrics
(2000)- et al.
Children with minimal sensorineural hearing loss: prevalence, educational performance, and functional status
Ear Hear
(1998)