Skip Ribbon Commands
Skip to main content

Language Development Laboratory

The overall goal of our research program is to examine the outcomes of early-identified children who are deaf and hard of hearing and identify factors that explain performance differences among these children.

  • ​​​Overview

    Our lab strives to inform early intervention practices and optimize the development outcomes of children who are deaf or hard of hearing.

    Welcome to the Language Development Laboratory!

    Three primary projects are currently underway in the Language Development Laboratory. 

    Current Projects

    Outcomes of Children with Hearing Loss (OCHL) and Outcomes of School Age Children who are Hard of Hearing (OSACHH)

    The Language Development Lab is currently funded by a grant from the National Institutes of Health – National Institute on Deafness and Other Communication Disorders (R01 DC009560), awarded to Drs. Mary Pat Moeller and J. Bruce Tomblin. This multi-site collaborative study is in its second cycle of funding.  The first cycle, Outcomes of Children with Hearing Loss (OCHL), focused on longitudinal outcomes of children ages 6 months to 6 years.  The second cycle, Outcomes of School Age Children who are Hard of Hearing, is currently focused on examining the academic and linguistics outcomes of a subset of children from the OCHL study through their fourth grade academic year. 

    Within longitudinal and cross-sectional research designs, we compare speech, language, and social-cognitive development outcomes of hearing children to those of children who are hard of hearing. This study is a collaboration of investigators at the University of Iowa, Boys Town National Research Hospital, and the University of North Carolina at Chapel Hill.  Currently we are using longitudinal data from a large group of preschoolers to determine if early language delays have cascading effects on later academic abilities. These studies focus on early identification of children who are at risk for delays, and on finding improved methods for preventing and/or ameliorating delays so that children who are hard of hearing will achieve success in language and literacy.

    Many of the results from the first cycle of this grant were published in this Ear and Hearing Supplement volume. More specific information on these ongoing projects may be accessed at OCHLStudy.org.

     

    Vocal Development Landmarks ​Interview

    As part of the OCHL study, researchers (Mary Pat Moeller and Sandie Bass-Ringdahl) developed an experimental version of a parent report scale designed to measure early landmarks in children's vocal development. The measure is now called the Vocal Development Landmarks Interview (VDLI). See results from the OCHL study using this parent-report scale. The development of the measure was motivated by a need for tools to measure the effects of recent advances in early identification of hearing loss on the vocal and speech development of infants and toddlers. Such tools are necessary to support research on outcomes and monitoring of intervention effectiveness. Drs. Moeller and Bass-Ringdahl recognized that caregivers may be in a unique position to provide insights into their children's vocal development, which motivated the use of a parent-interview format.

    This unique assessment tool has undergone revision as a result of our research to date. The examiner asks the parent a series of questions that are accompanied by power point slides. These slides include audio samples of authentic infant vocalizations, often presented in a paired-comparison format.  These audio demonstrations of the target vocal behaviors are intended to make the target vocal landmarks clear and understandable to parents. This minimizes the use of unfamiliar or complex terms and/or adult demonstrations of the behaviors. The tool comprises four sections 1) Warm-up, 2) Precanonical Behaviors, 3) Canonical Behaviors, and 4) Word Productions. Results to date indicate that this tool is sensitive to changes in children's prelexical and early linguistic development, and to developmental differences among the groups at 18-months of age. 

    Our laboratory is currently involved in conducting validation studies of the VDLI with caregivers of typically-developing infants and toddlers.  This work included administering the VDLI to parents of 160 typically developing infants between the ages of 6 months and 21 months were given the VDLI interview. These data were presented at the Society for Research in Child Language Disorders in June of 2016.

    Additionally, forty of those parents agreed to collect a full-day audio recording in close proximity to the interview. Segments of those recordings are being analyzed and coded to determine the degree to which parents and researchers agree about the vocal behaviors of the infants. These findings will lead to further revision of the scale.  Full day recordings incorporate technology from the Language ENvironment Analysis (LENA, pictured right). 

    Within the VDLI validation project, researchers listen to highly vocal segments from the recordings of the infants and toddlers and classify the frequency of specific developmental behaviors, which will then be compared to parent reports.  The photo below shows a LENA software report that guides the identification of these highly vocal segments.

    Clinical Measurement Core

    Research staff in the Language Development Laboratory also offer CORE support services for the Center for Perception and Communication in Children (CPCC).  The CPCC is funded by a Center of Biomedical Research Excellence (COBRE) grant awarded to Boys Town National Research Hospital by the NIH. The CPCC provides a unique scientific mentoring environment for five junior faculty with interest in understanding the consequences of childhood hearing loss for speech and language development, perception, and processing.  The Clinical Measurement Core provides junior faculty access to a multidisciplinary team of clinical experts, who administer clinical measures, and also offer consultation, shared data access, participant tracking, and support for interpretation of clinical measures.

    Research objectives include 1) operating a centralized clinical assessment and consulting center, 2) implementing routine quality controls, and 3) developing a shared database of demographic and outcome data.

    The CMC model was presented at the Society for Research in Child Language Disorders in June of 2016.

  • Our Team

    Outcomes of School Age Children who are Hard of Hearing (OSACHH)

    Principal Investigator

    Mary Pat Moeller, Ph.D., CCC-A, is the Director of the Center for Childhood Deafness and the Language Development Laboratory at Boys Town National Research Hospital in Omaha, NE. After many years of clinical work in rehabilitative Audiology and early intervention, she obtained a Ph.D. in child language and deafness from the University of Nebraska at Lincoln. Her research interests include mother-child interaction, theory of mind development in children who are deaf and hard of hearing and the study of factors influencing the outcomes of children who are hard of hearing. She directed a team at BTNRH in the development of a website for families whose infants refer from newborn hearing screening (www.babyhearing.org; www.audiciond​elbebe). Dr. Moeller is co-principal investigator with Dr. J. Bruce Tomblin at the University of Iowa of two prospective, longitudinal studies of the outcomes of children who are hard of hearing. Dr. Moeller has published widely and has lectured internationally on topics related to early development in children who are deaf or hard of hearing. She serves as a consultant to the Communication Development Lab and collaborates frequently with Dr. Ambrose.

    Team Members

    Sophie E. Ambrose, Ph.D., CCC-SLP, is the director of the Communication Development Lab. Dr. Ambrose completed her Ph.D. in communication disorders at the University of Kansas and her postdoctoral training with Dr. Mary Pat Moeller at Boys Town National Research Hospital. Additionally, she spent four years as a speech-language specialist on the pediatric cochlear implant team and a research associate at the House Ear Institute.  Dr. Ambrose is a co-investigator on the Outcomes of School Age Children who are Hard of Hearing study. Additionally, she is the principal investigator on an NIH-NIDCD funded grant entitled "Contributions of Gesture to the Linguistic Outcomes of Children with Hearing Loss" and a project director in the CPCC (project title: Efficacy of an Early Intervention Addressing the Needs of Children with Hearing Loss.") Dr. Ambrose's research efforts focus on methods for improving outcomes of young children with hearing loss.

    Abby J. Bogatz, M.A., CF-SLP, is a Clinical Fellow in Speech-Language Pathology who has a Bilingual/Multicultural Emphasis Certificate. Ms. Bogatz obtained a B.S. in Spanish and Psychology at the University of Nebraska-Lincoln.  Abby was inspired to go to the University of Minnesota for a master's degree after working as a teacher aide in the BTNRH preschool program for children who are deaf or hard of hearing.  She returned to BTNRH in May of 2016 and in addition to working with young children who are deaf or hard of hearing, she provides intervention and support for our Spanish speaking children and their families.  Ms. Bogatz is the newest member of our research team.  She serves as a research SLP on the Outcomes of School Age Children who are Hard of Hearing project.  In this role, Abby is involved in data collection and analysis, preparation of language transcripts, and data entry.

    Meaghan Foody, M.S., CCC-SLP received a bachelor's degree in Speech, Language and Hearing Sciences at Purdue University and then went on to receive a Master of Science degree in Speech-Language Pathology with and emphasis in Listening and Spoken Language from Utah State University.  She completed her clinical fellowship at Boys Town National Research Hospital, and has served on our staff for two years.  Meaghan provides clinical services for preschool-aged children who are deaf or hard of hearing, and she is a member of the cochlear implant team. Ms. Foody also serves as a research SLP on the Outcomes of School Age Children who are Hard of Hearing project.  In this role, Meaghan is involved in data collection and analysis, preparation of language transcripts, and data entry.

    Ryan McCreery, PhD, is the Director of Audiology and a staff scientist at Boys Town National Research Hospital, where his NIH-funded research focuses on the influences of linguistic and cognitive factors on speech recognition in children with hearing loss. He also collaborates with the Hearing and Amplification Research Laboratory, where his research attempts to identify factors that influence speech recognition with hearing aids for children, including hearing aid signal processing strategies. He has a Ph.D. in Human Sciences from the University of Nebraska at Lincoln and was a clinical audiologist for seven years prior to obtaining his Ph.D. As part of the OSACHH Research Team and the Principal Investigator of the Complex Listening Project, he applies his interests in pediatric speech recognition and amplification to helping to improve the understanding of how these factors influence communicative outcomes in children.   Ryan received the Early Career Contributions to Research Award from ASHA in 2013.

    Sue Nutty, M.S., is a research assistant in the Language Development Laboratory.  Sue received an MS in Sports Administration from Eastern Kentucky University.  She is an educator and swim coach by trade, as well as an avid and skilled kayaker who leads multi-day trips in the wilderness. She contributes in numerous ways to the daily function of the lab, including language transcription, coding, data entry, contacting educators, and so forth.  Sue also provides administrative support to the Educational Interpreter Performance Assessment (EIPA) team, which regulates the national testing process for educationally-based sign language interpreters.

    Meredith Spratford, AuD, CCC-A, is a staff research audiologist at Boys Town National Research Hospital.  She is a research assistant for the OSACHH and Complex Listening studies, as well as the manager for the Audibility, Perception, and Cognition laboratory.  Merry enjoys presenting at local and national conventions and meetings, and has been an active member in creating manuscripts for publication.  She loves meeting with families and watching the children grow in their abilities from year to year.

    Barb Peterson, MHD, is Laboratory Manager for the Clinical Measurement Core and other Developmental Studies at Boys Town National Research Hospital.  She obtained her Master of Human Development degree from the University of Kansas. She is in charge of scheduling for the CMC, OSACHH, and other studies as well as day to day operations of the labs.  Barb and her husband Jeff have two Deaf daughters, and she has a vast knowledge of raising and educating Deaf children.  Sharing her experiences and parent perspective with study families has been a valuable asset to the projects.

    Vocal Development Landmarks Interview (VDLI) Team

    Along with Mary Pat Moeller, Ph.D. and Sophie Ambrose, Ph.D., Anne Thomas is leading our current efforts on this project as part of her dissertation project. 

    Anne Thomas, M Ed, is a doctoral student at the University of Nebraska-Lincoln.  She is currently completing her dissertation project in the Language Development Laboratory with oversight from Dr. Moeller, Dr. Ambrose, her dissertation committee, and her UNL advisor, Dr. Chris Marvin.  Anne, who is fluent in ASL, was a teacher of the deaf in Prince William County Schools and at the Scranton (PA) School for Children who are Deaf or Hard of Hearing before pursuing her graduate studies at UNL.    For three years, Anne served as the Project Coordinator for the NU Data Research Project which focuses on using data-driven instruction, research and practices to foster the school success of students with disabilities.

  • Lab Spaces

    The Language Development Laboratory is located in the Lied Learning and Technology Center at Boys Town National Research Hospital.  It includes a number of spaces and places where our work is conducted.  One of the chief spaces is pictured below.

    Audiology Testing Booth

    This lab houses a double-walled sound-attenuated booth suite for hearing assessments. A hearing-aid analysis/probe-microphone system (Audioscan Verifit) is available to quantify real-ear gain as a function of frequency on an individual basis. It is connected to a clinical testing space for conducing speech, language, cognitive, and other clinical and experimental measures.

    Speech-Language and Cognitive Testing Area

    This testing room adjoins the Audiology testing area.  It is equipped with testing materials, computers, and equipment for session audio and video recording. 

    Speech-Language and Cognitive Testing Area for Young Children

    This area is now primarily used by the Communication Development Laboratory staff and is fully described in that section of the website.  It offers an alternative, child friendly environment for testing and recording the performance of younger children. 

    Lab Locations

    The OCHL and OSACHH studies include children from 17 states due to the multi-site nature of this project.  We are fortunate ​to have collaborating sites who have supported us by allowing us to test in their Centers.   These valued individuals and programs include

    1. Dr. Steve Boney in the Department of Special Education and Communication Disorders at University of Nebraska-Lincoln, Lincoln, NE,
    2. Christine Evans, private speech language pathologist in Richmond, VA,
    3. Dr. Jennifer Gutzwiller, AuD, of Educational Service Unit 10 in Kearney, Nebraska,
    4. Drs. Tiffany Johnson and Judy Widen and the Department of  Hearing and Speech at the University of Kansas Medical Center, Kansas City, KS,
    5. the Moog Center for Deaf Education in St. Louis, MO,
    6. Richmond Hearing Doctors in Richmond, VA,
    7. Via Christi Rehabilitation Hospital, Inc. in Wichita, KS, and 8) the University of Minnesota-Twin Cities Department of Speech, Language, and Hearing Sciences in Minneapolis, MN.
  • For Parents

    Upon Your Arrival

    Once you arrive at our lab, one of our research assistants will greet you and escort you to the laboratory. A lead researcher will walk you through the details related to participating in the study and will request that you formally give your consent for your child to participate. If your child is over the age of 7 years of age, we will go through forms to get his or her agreement to participate in the study. On your first visit to the laboratory, researchers will conduct an interview that includes some background questions about your family and your child's developmental and medical history.

    NOTE:  The Clinical Measurement Core (CMC) provides support to many different laboratories at Boys Town National Research Hospital.  We made a decision to centralize the collection of some routine measures (e.g., hearing tests, hearing aid measures, vocabulary testing), which are important when researchers analyze the results of their experiments. By centralizing these measures, we gain a lot of efficiency when children are participating in multiple studies. Typically, you will visit the CMC first, and then your child may be seen in a laboratory study to participate in specific experiments.

    During the Visit

    Research visits for data collection often occur in the summer to avoid competing with the school day. The length of the visit varies depending on the child, but lasts approximately 3 hours. The visit can be split into separate sessions if desired or needed, depending on the child's age. Routine measures conducted include:

    • Hearing evaluation or screening
    • Hearing aid evaluation for children who wear hearing aids
    • Assessment of speech and language skills such as vocabulary, concepts, and grammar
    • Assessment of conversational language skills where your child will be asked some questions and/or asked to tell a story about a short movie or book
    • Speech assessment involving labeling pictures to test how the child produces certain sounds
    • Assessment of memory skills, including memory for numbers and words
    • Assessment of nonverbal problem solving by recreating designs with blocks and by picking pictures that complete a sequence or pattern
    • Vision screening to rule out vision problems

    After the Visit

    At the end of the visit, your child will pick out a small prize and a book as our thank you for participating in the study. In addition, you will be compensated for your time on an hourly basis. If you would like to have your child's school receive a summary of your child's scores from the testing, please inform the staff working with you.

    Important Reminders

    We want to make this an enjoyable experience for you and your child/student, so if at any time you or your child needs a break or needs to end the visit, simply let us know.  If you have any questions before, during, or following any of your visits to our lab, just let us know!

    Directions and Parking

    From 30th street, you will see a sign with an arrow directing you toward Boys Town Patient and Visitor Parking on Cass Street. Turn east at that sign and follow the road under the walkway and take your first right into a parking lot. That lot is directly in front of our building, the Lied Learning and Technology Center. Park and come inside to the front desk and let them know you are here to visit the Language Development Lab. We’ll be called and will come down promptly to meet you!

    Driving ​Directions PDF

    The Lied Learning and Technology Center at
    Boys Town National Research Hospital
    425 North 30th Street
    Omaha, NE 68131
    (402) 452-5000s

  • Publications

    Moeller, M. P., Bass-Ringdahl, S., Ambrose, S. E., VanDam, M., & Tomblin, J. B. (2011). Understanding communication outcomes: New tools and insights. In R. C. Seewald & J. M. Bamford (Eds.), A Sound Foundation Through Early Amplification: Proceedings of the 2010 International Conference (pp. 245-259). Chicago, IL: Phonak AG. [PDF]

    Holte, L., Walker, E. A., Oleson, J., Spratford, M., Moeller, M. P., Roush, P. A., Tomblin, J. B., & Ou, H. (2012). Factors influencing follow-up to Newborn Hearing Screening for infants who are hard-of-hearing. American Journal of Audiology, 21, 163-174. doi:10.1044/1059-0889 [PMCID: PMC3435452]. [Journal Editor's Award] [LINK]

    Koehlinger, K., Van Horne, A., & Moeller, M. P. (2013). Grammatical outcomes of 3- and 6-year-old children who are hard of hearing. Journal of Speech, Language, and Hearing Research, 56(5), 1701-1714. doi:10.1044/1092-4388(2013/12-0188) [PMCID: PMC3951012]. [LINK] (Free PubMed Central Article)

    Tomblin, J. B., Oleson, J. J., Ambrose, S. E., Walker, E., & Moeller, M. P. (2014). The influence of hearing aids on speech and language development of children with hearing loss. JAMA Otolaryngology – Head & Neck Surgery, 140(5), 403-409. doi:10.1001/jamaoto.2014.267. [PMCID: PMC4066968] LINK] (Free PubMed Central Article)

    Walker, E. A., Spratford, M., Moeller, M. P., Oleson, J., Ou, H., Roush, P., & Jacobs, S. (2013). Predictors of hearing aid use time in children with mild-to-severe hearing loss. Language, Speech, and Hearing Services in Schools, 44, 73-88. doi:10.1044/0161-1461. [PMCID: PMC3543484] LINK] (Free PubMed Central Article)

    VanDam, M., Ambrose, S. E., & Moeller, M. P. (2012). Quantity of parental language in the home environments of hard-of-hearing 2-year-olds. Journal of Deaf Studies and Deaf Education. 17(4), 402-420. doi:10.1093/deafed/ens025 [PMCID: PMC3529623] [LINK]

    Ambrose, S. E., VanDam, M., & Moeller, M. P. (2014). Linguistic input, electronic media, and communication outcomes of toddlers with hearing loss. Ear and Hearing, 35(2), 139-147doi:10.1097/AUD.0b013e3182a76768 [PMCID: PMC3944057 [LINK] (Free PubMed Central Article)

    Ambrose, S. E., Unflat-Berry, L., Walker, E. A., Harrison, M., & Moeller, M. P. (2014). Speech sound production in 2-year-olds who are hard of hearing. American Journal of Speech-Language Pathology, 23, 91-104. doi:10.1044/2014_AJSLP-13-0039 [PMCID: PMC4035418] [LINK] (Free PubMed Central Article)​

    VanDam, M., Oller, D. K., Ambrose, S. E., Gray, S., Richards, J. A., Xu, D., Moeller, M. P. (2015). Automated vocal analysis of children with hearing loss and their typical and atypical peers. Ear and Hearing. 36(4), e146-52.Advance online publication. doi:10.1097/AUD.0000000000000138.  Will be submitted for PMCID in January 2016. LINK] (PubMed Abstract)

    Koehlinger, K., M., Owen Van Horne, A., J., Oleson, J., McCreery, R., Moeller, M. P. (2015).  The role of sentence position, allomorph, and morpheme type on accurate use of s-related morphemes by children who are hard of hearing.  Journal of Speech-Language-Hearing Research, 58, 396-409. [PMCID: PMC4398614 – available 10-1-2015] [LINK] (PubMed Abstract)

    Tomblin, J.B., Moeller, M.P. (2015).  Editorial: The Outcomes of Children with Hearing Loss study.  Ear and Hearing, Volume 36, Supplement 1, 1S-3S. doi:10.1097/AUD.0000000000000220 LINK]

    Moeller, M.P. & Tomblin, J.B. (2015).  An introduction to the Outcomes of Children with Hearing Loss study.  Ear and Hearing, Volume 36, Supplement 1, 4S-13S. doi:10.1097/AUD.0000000000000210 [LINK]

    Tomblin, J.B., Walker, E., McCreery, R., Arenas, R., Harrison, M., Moeller, M.P. (2015) Outcomes of Children with Hearing Loss: Data collection and methods.  Ear and Hearing, Volume 36, Supplement 1, 14S-23S. doi:10.1097/AUD.0000000000000212 [LINK]

    McCreery, R.W., Walker, E.A., Spratford, M., Bentler, R., Holte, L., Roush, P., Oleson, J., Van Buren, J., Moeller, M.P. (2015).  Longitudinal Predictors of Aided Speech Audibility. Ear and Hearing, Volume 36, Supplement 1, 24S-37S. doi:10.1097/AUD.0000000000000211 LINK]

    Walker, E., McCreery, R., Spratford, M., Oleson, J., Van Buren, J., Bentler, R., Roush, P., Moeller, M.P. (2015).  Trends and predictors of longitudinal hearing aid use for children who are hard of hearing.  Ear and Hearing, Volume 36, Supplement 1, 38S-47S. doi:10.1097/AUD.0000000000000208 [LINK]

    Ambrose, S.E., Walker, E., Unflat-Berry, L., Oleson, J., Moeller, M.P. (2015).  Quantity and quality of caregivers' linguistic input to 18-month and 3-year old children who are hard of hearing.  Ear and Hearing, Volume 36, Supplement 1, 48S-59S. doi:10.1097/AUD.0000000000000209 LINK]

    Tomblin, J.B., Harrison, M., Ambrose, S.E., Oleson, J., Moeller, M.P. (2015).  Language outcomes in young children with mild to severe hearing loss.  Ear and Hearing, Volume 36, Supplement 1, 76S-91S.  doi: 10.1097/AUD.0000000000000219. LINK]

    Moeller, M.P., Tomblin, J.B., and the OCHL Collaboration (2015).  Epilogue: Conclusions and implications for research and practice.  Ear and Hearing, Volume 36, Supplement 1, 92S-98S.  doi: 10.1097/AUD.0000000000000214. [LINK]

    Moeller, M.P., Tomblin, J.B. and the OCHL Collaboration (2015).  Afterword: Lessons learned about multicenter research collaboration.  Ear and Hearing, Volume 36, Supplement 1, 99S-101S.  doi: 10.1097/AUD.0000000000000215. LINK]

    Harrison, M., Page, T.A., Oleson, J., Spratford, M., Berry, L., Peterson, B., Wellhaven, A., Arenas, R., Moeller, M. P. (2015). Factors affecting early services for children who are hard of hearing. Language, Speech and Hearing Services in Schools. 47(1), 16-30.doi 10.1044/2015_LSHSS-14-0078. [PMID: 26440475]
    [LINK] (PubMed Abstract)

    Recent Clinical Publications

    Moeller, M.P., Ertmer, D., & Stoel-Gammon, C. (2016).  Promoting Language and Literacy ​Development in Children who are Deaf or Hard of Hearing:  An Introduction.  In M.P. Moeller, D.J. Ertmer, & C. Stoel-Gammon (Eds.).  Promoting Language and Literacy Development in Children who are Deaf or Hard of Hearing.  pp. 1-14.  Baltimore, MD:  Brookes Publishing.

    Moeller, M.P., & Mixan, Kristy (2016).  Family-Centered Early Intervention:  Principles, Practices & Supporting Research (birth to 3).  In M.P. Moeller, D.J. Ertmer, & C. Stoel-Gammon (Eds.).  Promoting Language and Literacy Development in Children who are Deaf or Hard of Hearing.  pp. 77-106.  Baltimore, MD:  Brookes Publishing.

    Moeller, M.P., & Cole, E. (2016). Family-centered early intervention:  Supporting spoken language development (birth to 3).  In M.P. Moeller, D.J. Ertmer, & C. Stoel-Gammon (Eds.).  Promoting Language and Literacy Development in Children who are Deaf or Hard of Hearing. pp. 107-148. Baltimore, MD:  Brookes Publishing.

    Moeller, M.P., Ertmer, D.J.,, & Stoel-Gammon, C. (2016). Afterword.  In M.P. Moeller, D.J. Ertmer, & C. Stoel-Gammon (Eds.).  Promoting Language and Literacy Development in Children who are Deaf or Hard of Hearing. pp. 409-412. Baltimore, MD:  Brookes Publishing.

    Sass-Lehrer, M., Moeller, M.P., & Stredler-Brown, A. (2015). What every early intervention provider should know. In M. Sass-Lehrer (Ed.). Early intervention for deaf and hard-of-hearing infants, toddlers, and their families: Interdisciplinary perspectives. pp. 3-36.  New York: Oxford University Press.

    Moeller, M. P., Carr, G., Seaver, L., Stredler-Brown, A., & Holzinger, D. (2013). Best practices in family-centered early ​intervention for children who are deaf or hard of hearing: An international consensus statement. Journal of Deaf Studies and Deaf Education, 18(4), 429-445. [LINK]