What Happens If a Speech Sound Disorder Goes Untreated? What the Research Actually Says
One of the most common questions parents ask before starting speech therapy is a version of this: "What happens if we don't?"
It's a fair question — and it deserves an honest, research-based answer rather than alarm or reassurance that isn't grounded in evidence.
The short answer is: it depends on the type of disorder, the severity, and the age of the child. But for a meaningful number of children, the consequences of untreated speech sound disorders extend well beyond how they sound when they talk.
First: Not All Speech Sound Disorders Are
the Same
This matters enormously for understanding outcomes.
Speech sound disorders fall along a spectrum. Some children have mild articulation errors affecting one or two sounds — like a frontal lisp or a distorted R — that primarily affect clarity. Others have phonological disorders involving patterns of errors that affect multiple sounds and intelligibility more broadly. Children with Childhood Apraxia of Speech (CAS) have a motor-based disorder that affects the planning and coordination of speech movements.
The research on long-term outcomes draws important distinctions between these presentations. A child with a single distortion error (like an isolated R) faces a different risk profile than a child with a moderate or severe phonological disorder. Keeping that distinction in mind is essential when reading any research on this topic — including this blog.
What the Research Shows
Literacy and Academic Achievement
The most consistent finding in the literature is the relationship between speech sound disorders and literacy. Poor speech sound production skills in kindergarten children have been associated with lower literacy outcomes, especially in children with concomitant language or phonological awareness difficulties.
This connection makes clinical sense. Learning to read requires phonological awareness — the ability to recognize and manipulate the sound structure of words. Children with phonological disorders often have underlying weaknesses in phonological representations that affect both their speech and their ability to map sounds to letters.
A study examining 263 children with persistent speech disorder found it was associated with poor educational attainment in English, mathematics, and science at ages 10–11 and 13–14 years. Children with persistent speech disorder were also more likely to be identified as having special educational needs.
Important nuance: This risk is most pronounced for children with persistent, moderate-to-severe phonological disorders — particularly those with co-occurring language difficulties. Children with isolated distortion errors affecting one or two sounds show a weaker association with academic outcomes. The research does not suggest that every child with a speech error will struggle academically — but it does identify a meaningful subgroup at elevated risk.
Social and Emotional Impact
Research consistently documents social and emotional challenges associated with speech sound disorders in school-age children. Children with residual speech errors face an increased risk of social, emotional, and academic challenges relative to their peers with typical speech.
Notably, these difficulties are not limited to severely unintelligible speakers — parents of children who were highly intelligible and exhibited only one or two sounds in error still endorsed a high degree of impact across multiple domains.
Some children with speech sound disorders reported a preference for activities that did not rely on verbal communication, such as art and sports — suggesting that the impact extends to how children choose to participate in the world around them.
These findings are not inevitable outcomes — they reflect tendencies observed across populations. Many children with speech sound disorders thrive socially and academically. But the research suggests that the risk is real and worth taking seriously.
Into Adulthood
For children whose speech difficulties persist through school age without intervention, the research suggests consequences that can extend well beyond childhood. Children with persisting speech difficulties may continue to have problems with oral communication, reading, writing, and social aspects of life as they transition to postsecondary education and vocational settings.
A 28-year follow-up study cited in the research literature found that adults with histories of moderate phonological disorders had less favorable academic outcomes than comparison groups — including lower high school grades and a greater likelihood of working in jobs requiring minimal academic preparation. This was observed even among individuals with intelligence in the normal range (Felsenfeld et al., as cited in Hitchcock et al., 2015).
Again — this research focuses on individuals with moderate to severe phonological histories, not mild isolated errors. But it underscores that for certain presentations, early treatment is not just preferable — it may be consequential.
What About Mild Errors — Like a Lisp or
Distorted R?
This is where honest nuance matters most.
Research on children with isolated distortion errors — such as a lateral lisp, frontal lisp, or distorted R — does not show the same level of academic risk as children with broader phonological disorders. Shriberg (2010) argued that distortion errors are not associated with adverse outcomes in education, and research supports that children whose errors are restricted to common clinical distortions perform similarly to controls on measures linked to literacy.
So why treat them?
Motor learning and automaticity. The longer an incorrect speech pattern is practiced, the more automatic it becomes. For R errors specifically, research indicates that errors solidify as motor patterns around age 8.5 (Shriberg et al., 1994). Treating earlier means a shorter, more efficient treatment course.
Social and emotional impact. Even mild errors can affect how children feel about speaking — particularly as they enter middle school and become more self-conscious. The research on social impact applies even to children with only one or two sounds in error.
Self-correction is unlikely. A distorted R or persistent lisp does not resolve on its own without intervention. Unlike some phonological processes that naturally resolve with development, distortion errors require targeted motor intervention to correct.
The Role of Treatment
It is worth stating clearly: evidence from systematic reviews has shown that intervention is effective for the majority of children with speech sound disorders and that these children do not make progress without intervention.
This doesn't mean every child with a speech error needs immediate intensive therapy. But it does mean that waiting indefinitely — particularly past the age thresholds supported by normative data — is rarely the right clinical decision.
The earlier treatment begins, the less established the error pattern, the shorter the treatment course, and the lower the risk of downstream effects on literacy, social confidence, and academic performance.
What This Means for Your Family
If your child has a speech sound disorder — whether it's a persistent R error, a lisp, phonological patterns that haven't resolved, or suspected apraxia — the research supports taking action rather than waiting.
The consequences of untreated speech sound disorders are not guaranteed, and they vary significantly by disorder type and severity. But the evidence is clear enough that waiting past expected developmental windows carries real risk — and that treatment works.
If you're not sure whether your child's speech warrants evaluation, the first step is a consultation with a licensed speech-language pathologist who can assess their specific presentation and give you a clear picture of what's needed and when.
Book a Free Parent Consultation →
References
Felsenfeld, S., Broen, P. A., & McGue, M. (1992). A 28-year follow-up of adults with a history of moderate phonological disorder: Linguistic and personality results. Journal of Speech and Hearing Research, 35(5), 1114–1125.
Hitchcock, E. R., McAllister Byun, T., Swartz, M., & Lazarus, R. (2015). Social, emotional, and academic impact of residual speech errors in school-age children: A survey study. Seminars in Speech and Language, 36(4), 283–294.
McCormack, J., McLeod, S., McAllister, L., & Harrison, L. J. (2009). A systematic review of the association between childhood speech impairment and participation across the lifespan. International Journal of Speech-Language Pathology, 11(2), 155–170.
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(5), 1127–1150.
Wren, Y., Miller, L. L., Peters, T. J., Emond, A., & Roulstone, S. (2016). Prevalence and predictors of persistent speech sound disorder at eight years old: Findings from a population cohort study. Journal of Speech, Language, and Hearing Research, 59(4), 647–673.
American Speech-Language-Hearing Association. (2023). Speech sound disorders: Articulation and phonology. ASHA Practice Portal. asha.org
Christina Burnham, MS CCC-SLP | CloudSpeech Online Therapy | cloudspeech.com | 512-765-4554