Developmental language disorder (DLD), also referred to as specific language impairment (SLI), affects over 7% of the population — more than autism spectrum disorders, intellectual disability, or attention deficit/hyperactivity disorder. Its impact on daily function and quality of life can be severe and it effects persist into adulthood, yet it is under recognized, under diagnosed, and the underlying mechanisms of the disorder are not well understood. Although the DLD can never be fully remediated, early identification and intervention is recommended to improve long term outcomes for these individuals. Unfortunately, DLD is difficult to diagnose in children under the age of four or five due to the late onset of clear clinical symptoms. A long-term objective of my research is to create a surveillance tool that can help pediatricians, speech-language pathologists, and other professionals more accurately identify which toddlers are at greatest risk for developing DLD based on risk factor exposure and early communicative behaviors. Preliminary results from two pilot studies have been presented at the American Academy of Pediatrics National Conference and the Symposium on Research in Childhood Language Disorders. The results of a related meta-analysis were recently published in the American Journal of Speech-Language Pathology.
Johanna Rudolph earned her clinical MS in speech-language pathology and her PhD in speech, language, and hearing sciences at Purdue University under the mentorship of Dr. Laurence Leonard. Her general research interests include early identification, treatment efficacy, and evidence-based practice in speech-language pathology. Her dissertation work focused on a method for developing a surveillance tool that could be used to identify toddlers who are at greatest risk for DLD/SLI. Her current research continues to focus on diagnostic criteria for DLD including empirical examination of clinical measures, but has extended into early identification of and screening for other speech and language disorders.
Research suggests that early intervention is the most effective and efficient approach for addressing the impairments associated with a variety of neurodevelopmental disorders. However, developmental communication disorders, including developmental language disorder and speech sound disorder, can be exceptionally difficult to diagnose in very early childhood because speech and language skills have yet to be established. The American Academy of Pediatrics has established an algorithm for identifying and addressing developmental disorders in children from 0-3 years. Surveillance is the first phase of this process and involves addressing parental concerns, collecting a developmental history, making behavioral observations, and identifying a child's risk and protective factors. I am interested in developing surveillance tools that combine well-known risk factors and early developing behavioral indicators into probability equations using logistic regression analyses. This type of tool differs from many that are currently used in clinical practice in that the included factors are entered into a formula in which the factors are weighted according to their experimentally-derived contribution to the predicted outcome. The risk scores calculated using this formula give an indication of the likelihood of a child developing the specified disorder - the higher the score, the higher the likelihood. Validated cut-off scores make this kind of tool easy to implement and easy to interpret, eliminating a lot of the guesswork involved in early identification of communication disorders.
While accurate and timely diagnosis of developmental communication disorders is important both for the individuals identified and for their families, it is even more important that, once a disorder has been diagnosed, steps are taken to improve the quality of life for those affected. Evidence-based practice is defined by ASHA as "the integration of research evidence with practitioner expertise and client preferences and values when making clinical decisions." This approach, especially the process of staying up-to-date on the most current and highest quality evidence, can be daunting in a busy clinical environment. I am interested in increasing the transparency of intervention research to facilitate its use by practicing clinicians. In particular, when performing reviews or implementing treatment studies, it is essential that (1) participant characteristics are well specified for the sake of comparison to individual clients, (2) intervention procedures are clearly outlined and replicable, (3) in addition to measures of group performance, outcomes for individual participants are reported and the suspected source of individual variation is discussed, and (4) the mechanisms responsible for the observed changes are articulated. Increased transparency will assist busy clinicians in the task of implementing evidence-based practice in the context of real-world clinical scenarios.
Rudolph, J. M. (2017). Case history risk factors for specific language impairment: A systematic review and meta-analysis. American Journal of Speech-Language Pathology, 26(3), 991-1010.
Rudolph, J. M., & Leonard, L. B. (2016). Early language milestones and specific language impairment. Journal of Early Intervention, 38(1), 41-58.
Rudolph, J. M., & Rudolph, S. (2015). Telepractice vs. on-site treatment: Are outcomes equivalent for school age children? EBP Briefs, 10(2), 1-15.
Rudolph, J. M., & Wendt, O. (2014). The efficacy of the cycles approach: A multiple baseline design. Journal of Communication Disorders, 47, 1-16.
Hassink, J. M., & Leonard, L. B. (2010). Within-treatment factors as predictors of outcomes following conversational recasting. American Journal of Speech-Language Pathology, 19(3), 213-224.
Hassink, J. M., & Wendt, O. (2010). Remediation of phonological disorders in preschool age children: Evidence for the cycles approach. EBP Briefs, 5(2), 1-7.
Rudolph, J. M., & Dollaghan, C. A. (in prep). The finite verb morphology composite: Values from a community sample.
Rudolph, J. M. & Dollaghan, C. A. (2017). The finite verb morphology composite: Values from a community sample. Seminar presented at the Annual Convention of the American Speech-Language-Hearing Association, Los Angeles, CA, November 2017.
Rudolph, J. M. & Campbell, T., & McGlothlin, J. (2017). The Speakeasy app: A feasibility study. Flash session presented at the Annual Convention of the American Speech-Language-Hearing Association, Los Angeles, CA, November 2017.
Rudolph, J. M. (2017). Socioeconomic status: Associations with language ability in kindergarten-age children. Poster presented at the 2017 Biennial Meeting of the Symposium for Research in Child Development, Austin, TX, April 2017.
Rudolph, J. M. (2015). Risk factors for specific language impairment: A systematic review and meta-analysis. Seminar presented at the Annual Convention of the American Speech-Language-Hearing Association, Denver, CO, November 2015.
Rudolph, J. M. (2015). Late talkers: Predictive accuracy of semantic vs. syntactic delays. Poster presented at the Symposium on Research in Childhood Language Disorders, Madison, WI, June 2015.
Rudolph, J. M., & Leonard, L. B. (2014). Identifying toddlers at risk for language disorders: A screening tool. Poster presented at the American Academy of Pediatrics National Conference & Exhibition, San Diego, CA, October 2014.
Rudolph, J. M. (2013). Deriving non-linguistic measures from the preferential looking paradigm. Technical Session presented at the Annual Convention of the American Speech-Language-Hearing Association, Chicago, IL, November 2013.
Rudolph, J. M., & Leonard, L. B. (2013). Predicting language outcomes: A risk factor model. Poster presented at the Symposium on Research in Childhood Language Disorders, Madison, WI, June 2013.
Rudolph, J. M., Hollich, G. J., & Leonard, L. B. (2013). Infant speed of processing: Measures of global cognitive ability or separable cognitive skills? Poster presented at the 2013 Biennial Meeting of the Symposium for Research in Child Development, Seattle, WA, April 2013.
Hassink, J. M., & Wendt, O. (2012). Efficacy of the cycles approach for remediation of phonological disorders. Seminar presented at the International Child Phonology Conference, Minneapolis, MN, June 2012.
Hassink, J. M., & Leonard, L. B. (2010). Learning through recasts: Within-treatment factors that facilitate target acquisition in preschoolers with SLI. Poster presented at the Symposium on Research in Childhood Language Disorders, Madison, WI, June 2010.
Hassink, J. M., & Wendt, O. (2008). Impact of the Cycles Approach on phonological remediation: A critically appraised topic. Poster presented at the Annual Convention of the American Speech-Language-Hearing Association, Chicago, IL, November 2008.
Hassink, J. M., & Wendt, O. (2008). A critically appraised topic on the effectiveness of the Cycles Approach for phonological disorders. Poster presented at the International Child Phonology Conference, West Lafayette, IN, June 2008.