Purpose

The purpose of this study was to document, validate, and corroborate effect size (ES) for single-subject design in treatment of children with functional phonological disorders; to evaluate potential child-specific contributing variables relative to ES; and to establish benchmarks for interpretation of ES for the population.

Method

Data were extracted from the Developmental Phonologies Archive for 135 preschool children with phonological disorders who previously participated in single-subject experimental treatment studies. Standard mean differenceall with correction for continuity was computed to gauge the magnitude of generalization gain that accrued longitudinally from treatment for each child with the data aggregated for purposes of statistical analyses.

Results

ES ranged from 0.09 to 27.83 for the study population. ES was positively correlated with conventional measures of phonological learning and visual inspection of learning data on the basis of procedures standard to single-subject design. ES was linked to children's performance on diagnostic assessments of phonology but not other demographic characteristics or related linguistic skills and nonlinguistic skills. Benchmarks for interpretation of ES were estimated as 1.4, 3.6, and 10.1 for small, medium, and large learning effects, respectively.

Conclusion

Findings have utility for single-subject research and translation of research to evidence-based practice for children with phonological disorders.

References

  • Bain, B. A., & Dollaghan, C. A. (1991). The notion of clinically significant change.Language, Speech, and Hearing Services in Schools, 22, 264–270.
  • Baker, E., & McLeod, S. (2011). Evidence-based practice for children with speech sound disorders: Part 1 narrative review.Language, Speech, and Hearing Services in Schools, 42, 102–139.
  • Barnett, A. G., van der Pols, J. C., & Dobson, A. J. (2005). Regression to the mean: What it is and how to deal with it.International Journal of Epidemiology, 24, 215–220.
  • Beeson, P., & Robey, R. (2006). Evaluating single-subject treatment research: Lessons learned from the aphasia literature.Neuropsychology Review, 16, 161–169.
  • Bothe, A. K., & Richardson, J. D. (2011). Statistical, practical, clinical, and personal significance: Definitions and applications in speech-language pathology.American Journal of Speech-Language Pathology, 20, 233–242.
  • Brumbaugh, K., & Smit, A. (2013). Treating children ages 3-6 who have speech sound disorder: A survey.Language, Speech, and Hearing Services in Schools, 44, 306–319.
  • Busk, P. L., & Serlin, R. C. (1992). Meta-analysis for single-case research.In T. R. Kratochwill & J. R. Levin (Eds.), Single-case research design and analysis (pp. 187–212). Mahwah, NJ: Erlbaum.
  • Byiers, B. J., Reichle, J., & Symons, F. J. (2012). Single-subject experimental design for evidence-based practice.American Journal of Speech-Language Pathology, 21, 397–414.
  • Campbell, J. M. (2004). Statistical comparison of four effect sizes for single-subject designs.Behavior Modification, 28, 234–246.
  • Campbell, J. M., & Herzinger, C. V. (2010). Statistics and single subject research methodology.In D. L. Gast (Ed.), Single subject research methodology in behavioral sciences (pp. 417–453). New York, NY: Routledge.
  • Carroll, J. M., Snowling, M. J., Hulme, C., & Stevenson, J. (2003). The development of phonological awareness in preschool children.Developmental Psychology, 39, 913–923.
  • Cohen, J. (1988). Statistical power analysis for the behavioral sciences (2nd ed.). Mahwah, NJ: Erlbaum.
  • Crosbie, J. (1987). The inability of the binomial test to control Type I error with single-subject data.Behavioral Assessment, 9, 141–150.
  • Dean, E. C., Howell, J., Waters, D., & Reid, J. (1995). Metaphon: A metalinguistic approach to the treatment of phonological disorder in children.Clinical Linguistics & Phonetics, 9, 1–19.
  • Dinnsen, D. A. (1984). Methods and empirical issues in analyzing functional misarticulation.In M. Elbert, D. A. Dinnsen, & G. Weismer (Eds.), Phonological theory and the misarticulating child (ASHA Monographs No. 22) (pp. 5–17). Rockville, MD: American Speech-Language-Hearing Association.
  • Dollaghan, C. A. (2007). Handbook for evidence-based practice in communication disorders. Baltimore, MD: Brookes.
  • Dollaghan, C. A., & Campbell, T. F. (1998). Nonword repetition and child language impairment.Journal of Speech, Language, and Hearing Research, 41, 1136–1146.
  • Dunn, L. M., & Dunn, D. M. (1981). Peabody Picture Vocabulary Test–Revised. Circle Pines, MN: American Guidance Service.
  • Dunn, L. M., & Dunn, D. M. (1997). Peabody Picture Vocabulary Test–Third Edition. Circle Pines, MN: AGS.
  • Dunn, L. M., & Dunn, D. M. (2007). Peabody Picture Vocabulary Test–Fourth Edition. Circle Pines, MN: AGS.
  • Durlak, J. A. (2009). How to select, calculate, and interpret effect sizes.Journal of Pediatric Psychology, 34, 917–928.
  • Edeal, D. M., & Gildersleeve-Neumann, C. E. (2011). The importance of production frequency in therapy for childhood apraxia of speech.American Journal of Speech-Language Pathology, 20, 95–110.
  • Faith, M. S., Allison, D. B., & Gorman, B. S. (1996). Meta-analysis of single-case research.In R. D. Franklin, D. B. Allison, & B. S. Gorman (Eds.), Design and analysis of single-case research (pp. 245–277). Mahwah, NJ: Erlbaum.
  • D. L. Gast (Ed.) (2010). Single subject research methodology in behavioral sciences. New York, NY: Routledge.
  • Gast, D. L., & Spriggs, A. D. (2010). Visual analysis of graphic data.In D. L. Gast (Ed.), Single subject research methodology in behavioral sciences (pp. 199–233). New York, NY: Routledge.
  • Gierut, J. A. (1998). Treatment efficacy: Functional phonological disorders in children.Journal of Speech, Language, and Hearing Research, 41, S85–S100.
  • Gierut, J. A. (1999). Syllable onsets: Clusters and adjuncts in acquisition.Journal of Speech, Language, and Hearing Research, 42, 708–726.
  • Gierut, J. A. (2001). Complexity in phonological treatment: Clinical factors.Language, Speech, and Hearing Services in Schools, 32, 229–241.
  • Gierut, J. A. (2007). Phonological complexity and language learnability.American Journal of Speech-Language Pathology, 16, 6–17.
  • Gierut, J. A. (2008a). Fundamentals of experimental design and treatment.In D. A. Dinnsen & J. A. Gierut (Eds.), Optimality theory, phonological acquisition and disorders (pp. 93–118). London, United Kingdom: Equinox.
  • Gierut, J. A. (2008b). Phonological disorders and the developmental phonology archive.In D. A. Dinnsen & J. A. Gierut (Eds.), Optimality theory, phonological acquisition and disorders (pp. 37–92). London, United Kingdom: Equinox.
  • Gierut, J. A., & Morrisette, M. L. (2011). Effect size in clinical phonology.Clinical Linguistics & Phonetics, 25, 975–980.
  • Gierut, J. A., & Morrisette, M. L. (2012a). Age-of-word acquisition effects in treatment of children with phonological delays.Applied Psycholinguistics, 33, 121–144.
  • Gierut, J. A., & Morrisette, M. L. (2012b). Density, frequency and the expressive phonology of children with phonological delay.Journal of Child Language, 39, 804–834.
  • Gierut, J. A., & Morrisette, M. L. (2014). How to meet the neighbors: Modality effects on phonological generalization.Clinical Linguistics & Phonetics, 28, 477–492.
  • Gierut, J. A., Morrisette, M. L., & Ziemer, S. (2010). Nonwords and generalization in children with phonological disorders.American Journal of Speech-Language Pathology, 19, 167–177.
  • Gierut, J. A., Simmerman, C. L., & Neumann, H. J. (1994). Phonemic structures of delayed phonological systems.Journal of Child Language, 21, 291–316.
  • Glass, G. (1977). Integrating findings: The meta-analysis of research.Review of Research in Education, 5, 351–379.
  • Goldman, R., & Fristoe, M. (1986). Goldman-Fristoe Test of Articulation. Circles Pines, MN: AGS.
  • Goldman, R., & Fristoe, M. (2000). Goldman-Fristoe Test of Articulation–Second Edition. Circle Pines, MN: AGS.
  • Hersen, M., & Barlow, D. H. (1976). Single case experimental designs: Strategies for studying behavior change. New York, NY: Pergamon Press.
  • Hesketh, A., Adams, C., Nightingale, C., & Hall, R. (2000). Phonological awareness therapy and articulatory training approaches for children with phonological disorders: A comparative outcome study.International Journal of Language & Communication Disorders, 35, 337–354.
  • Horner, R. H., Carr, E. G., Halle, J., McGee, G., Odom, S., & Wolery, M. (2005). The use of single-subject research to identify evidence-based practice in special education.Exceptional Children, 71, 165–179.
  • R. H. Hoyle (Ed.). (1999). Statistical strategies for small sample research. Thousand Oaks, CA: Sage.
  • Hresko, W. P., Reid, D. K., & Hammill, D. D. (1981). Test of Early Language Development. Austin, TX: Pro-Ed.
  • Hresko, W. P., Reid, D. K., & Hammill, D. D. (1991). Test of Early Language Development–Second Edition. Austin, TX: Pro-Ed.
  • Hresko, W. P., Reid, D. K., & Hammill, D. D. (1999). Test of Early Language Development–Third Edition. Austin, TX: Pro-Ed.
  • Ingram, D. (2002). The measurement of whole word productions.Journal of Child Language, 29, 713–734.
  • Ingram, D., & Ingram, K. D. (2001). A whole-word approach to phonological analysis and intervention.Language, Speech, and Hearing Services in Schools, 32, 271–283.
  • Jacobson, N. S., & Truax, P. (1991). Clinical significance: A statistical approach to defining meaningful change in psychotherapy research.Journal of Consulting and Clinical Psychology, 59, 12–19.
  • Kirk, S. A., McCarthy, J. J., & Kirk, W. D. (1968). Illinois test of psycholinguistic abilities–revised. Chicago, IL: University of Illinois Press.
  • Komrey, J., & Foster-Johnson, L. (1996). Determining the efficacy of intervention: The use of effect sizes for data analysis in single-subject research.The Journal of Experimental Education, 65, 73–93.
  • Kratochwill, T. R. (1978). Single subject research: Strategies for evaluating change. New York, NY: Academic Press.
  • Landis, J. R., & Koch, G. G. (1977). The measurement of observer agreement for categorical data.Biometrics, 33, 159–174.
  • Law, J., Garrett, Z., & Nye, C. (2004). The efficacy of treatment for children with developmental speech and language delay/disorder: A meta-analysis.Journal of Speech, Language, and Hearing Research, 47, 924–943.
  • Levine, M. N. (1986). Leiter International Performance Scale. Chicago, IL: Stoelting.
  • Linden, A. (2013). Assessing regression to the mean effects in health care initiatives.BMC Medical Research Methodology, 13, 119. Retrieved from http://www.biomedcentral.com/1471-2288/13/119
  • McReynolds, L. V., & Kearns, K. P. (1983). Single-subject experimental designs in communicative disorders. Baltimore, MD: University Park Press.
  • Miccio, A. W., & Elbert, M. (1996). Enhancing stimulability: A treatment program.Journal of Communication Disorders, 29, 335–351.
  • Miccio, A. W., Gallagher, E., Grossman, C. B., Yont, K. M., & Vernon-Feagans, L. (2001). Influence of chronic otitis media on phonological acquisition.Clinical Linguistics & Phonetics, 15, 47–51.
  • Morrisette, M. L., & Gierut, J. A. (2002). Lexical organization and phonological change in treatment.Journal of Speech, Language, and Hearing Research, 45, 143–159.
  • Morrisette, M. L., Hoover, J. R., & Gierut, J. A. (2012, June). Lexical neighborhoods in recognition by children with phonological disorders. 33rd Annual Symposium on Research in Child Language Disorders, Madison, WI.
  • Nesselroade, J. R., Stigler, S. M., & Baltes, P. B. (1980). Regression toward the mean and the study of change.Psychological Bulletin, 88, 622–637.
  • Newcomer, P. L., & Hammill, D. D. (1988). Test of Language Development–Primary: Second Edition. Austin, TX: Pro-Ed.
  • Newcomer, P. L., & Hammill, D. D. (1997). Test of Language Development–Primary: Third Edition. Austin, TX: Pro-Ed.
  • Nippold, M. A. (2001). Phonological disorders and stuttering in children: What is the frequency of co-occurrence?.Clinical Linguistics & Phonetics, 15, 219–228.
  • Olive, M. L., & Smith, B. W. (2005). Effect size calculations and single subject designs.Educational Psychology, 25, 313–324.
  • Olswang, L. B. (1998). Treatment efficacy research.In C. M. Frattali (Ed.), Measuring outcomes in speech-language pathology (pp. 134–150). New York, NY: Thieme.
  • Parker, R. I., Hagan-Burke, S., & Vannest, K. (2007). Percentage of all non-overlapping data (PAND): An alterative to PND.The Journal of Special Education, 40, 194–204.
  • Powell, T. W. (1991). Planning for phonological generalization: An approach to treatment target selection.American Journal of Speech-Language Pathology, 1, 21–27.
  • Powell, T. W., Elbert, M., Miccio, A. W., Strike-Roussos, C., & Brasseur, J. (1998). Facilitating [s] production in young children: An experimental evaluation of motoric and conceptual treatment approaches.Clinical Linguistics & Phonetics, 12, 127–146.
  • Robbins, J., & Klee, T. (1987). Clinical assessment of oropharyngeal motor development in young children.Journal of Speech and Hearing Disorders, 52, 271–277.
  • Robey, R. R. (1994). The efficacy of treatment for aphasic persons: A meta-analysis.Brain and Language, 47, 582–608.
  • Robey, R. R. (1998). A meta-analysis of clinical outcomes in the treatment of aphasia.Journal of Speech, Language, and Hearing Research, 41, 172–187.
  • Robey, R. R., Schultz, M. C., Crawford, A. B., & Sinner, C. A. (1999). Review: Single-subject clinical-outcome research: Designs, data, effect sizes, and analyses.Aphasiology, 13, 445–473.
  • Roid, G. H., & Miller, L. J. (1997). Leiter International Performance Scale–Revised. Chicago, IL: Stoelting.
  • Rosenthal, R., & Rosnow, R. (2008). Essentials of behavioral research: Methods and data analysis (3rd ed.). Boston, MA: McGraw-Hill.
  • Rvachew, S., & Grawburg, M. (2006). Correlates of phonological awareness in preschoolers with speech sound disorders.Journal of Speech, Language, and Hearing Research, 49, 74–87.
  • Scotti, J. R., Evans, I. M., Meyer, L. H., & Walker, P. (1991). A meta-analysis of intervention research with problem behavior: Treatment validity and standards of practice.American Journal on Mental Retardation, 93, 233–256.
  • Scruggs, T. E., Mastropieri, M. A., & Casto, G. (1987). The quantitative synthesis of single-subject research methodology and validation.Remedial and Special Education, 8, 24–33.
  • Shriberg, L. D., Austin, D., Lewis, B. A., McSweeny, J. L., & Wilson, D. L. (1997). The percentage of consonants correct (PCC) metric: Extensions and reliability data.Journal of Speech, Language, and Hearing Research, 40, 708–722.
  • Shriberg, L. D., & Kwiatkowski, J. (1994). Developmental phonological disorders. I: A clinical profile.Journal of Speech and Hearing Research, 37, 1100–1126.
  • Shriberg, L. D., Kwiatkowski, J., & Gruber, F. A. (1994). Developmental phonological disorders. II: Short-term speech-sound normalization.Journal of Speech and Hearing Research, 37, 1127–1150.
  • Shriberg, L. D., & Lof, G. L. (1991). Reliability studies in broad and narrow phonetic transcription.Clinical Linguistics & Phonetics, 5, 225–279.
  • Shriberg, L. D., Lohmeier, H. L., Campbell, T. F., Dollaghan, C. A., Green, J. R., & Moore, C. A. (2009). A nonword repetition task for speakers with misarticulations: The syllable repetition task (SRT).Journal of Speech, Language, and Hearing Research, 52, 1189–1212.
  • Shriberg, L. D., Tomblin, J. B., & McSweeny, J. L. (1999). Prevalence of speech delay in 6-year-old children and comorbidity with language impairment.Journal of Speech, Language, and Hearing Research, 42, 1461–1481.
  • Stoel-Gammon, C. (1985). Phonetic inventories, 15-24 months: A longitudinal study.Journal of Speech and Hearing Research, 28, 505–512.
  • Swanson, H. L., & Sachse-Lee, C. (2000). A meta-analysis of single-subject–design intervention research for students with LD.Journal of Learning Disabilities, 33, 114–136.
  • Thompson, C. K., den Ouden, D. B., Bonakdarpour, B., Garibaldi, K., & Parrish, T. B. (2010). Neural plasticity and treatment-induced recovery of sentence processing in agrammatism.Neuropsychologia, 48, 3211–3227.
  • Tyler, A. A., & Figurski, G. R. (1994). Phonetic inventory changes after treating distinctions along an implicational hierarchy.Clinical Linguistics & Phonetics, 8, 91–108.
  • Vihman, M. M., Ferguson, C. A., & Elbert, M. (1986). Phonological development from babbling to speech: Common tendencies and individual differences.Applied Psycholinguistics, 7, 3–40.
  • Weiner, F. F. (1981). Treatment of phonological disability using the method of meaningful minimal contrast: Two case studies.Journal of Speech and Hearing Disorders, 46, 97–103.
  • Wiig, E. H., Secord, W., & Semel, E. (1992). Clinical evaluation of language fundamentals–preschool. San Antonio, TX: Harcourt Brace.
  • Wiig, E. H., Secord, W., & Semel, E. (2004). Clinical evaluation of language fundamentals–preschool (2nd ed.). San Antonio, TX: Harcourt Brace.
  • A. L. Williams, S. McLeod, & R. J. McCauley (Eds.). (2010). Interventions for speech sound disorders in children. Baltimore, MD: Brookes.
  • Williams, K. T. (1997). Expressive Vocabulary Test. Circle Pines, MN: AGS.
  • Williams, K. T. (2007). Expressive Vocabulary Test–Second Edition. Circle Pines, MN: AGS.
  • Wolery, M., Busick, M., Reichow, B., & Barton, E. E. (2010). Comparison for overlap methods for quantitatively synthesizing single-subject data.The Journal of Special Education, 44, 18–28.

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