A look at the risk factors for persistent stuttering.
I’ve heard a lot of debate in the speech therapy world about best practices when it comes to treating preschoolers who stutter. Is it better to just treat right away? Is it better to wait and monitor the child’s speech to see if the stuttering resolves on its own? I’ve done a deep dive on some of the most recent research in order to better understand this dilemma in my own practice, and I’m going to share what I’ve learned with you.
There have been countless studies on the risk factors for persistent stuttering. The most common risk factors studied include age at onset, sex, family history of stuttering, stuttering severity, speech and language skills, and temperament. So which of these have been shown to have a correlation with persistent stuttering? Are there some risk factors that should weigh more heavily on our decision making than others? And are there certain combinations of risk factors that are shown to lead to persistence or recovery?
A meta-analysis of the clinical characteristics associated with persistent stuttering was conducted in September 2020 by Singer et al. and found that these risk factors were associated with a higher chance of persistent stuttering (in order of how strongly they correlated with persistence):
Family history of stuttering: Children who had a first- or second-degree relative who stuttered were 1.89 times more likely to persist in stuttering, regardless of whether that family member recovered from or persisted in stuttering.
Sex: Males were 1.48 times more likely to persist in stuttering than females.
Age at onset: Children who persisted in stuttering were, on average, older at the age of onset than children who recovered from stuttering. Children in the persistent group had an average onset age of 39.6 months, whereas children in the recovered group had an average onset age of 34.4 months.
Lower speech sound accuracy: Children in the persistent group had articulation skills that were significantly lower than those of the children in the recovered group.
Higher frequency of stuttering-like disfluencies (SLDs): Children who persisted in stuttering had a higher frequency of stuttering-like disfluencies than did the children who recovered. This means they presented with more sound/syllable repetitions, whole-word repetitions, prolongations, and blocks.
Lower receptive and expressive language skills: Children in the persistent group had receptive and expressive language skills that were lower, on average, than those of children in the recovered group.
It is important to note that Singer et al. did not find the following to be significant when it came to whether a child would persist or recover from stuttering:
Whether a family member who stuttered had recovered or persisted in stuttering
Overall percentage of syllables stuttered
Parent or clinician assessment of stuttering severity (using stuttering severity ratings)
Frequency of non-stuttering like disfluencies (i.e., interjections, phrase repetitions, revisions)
Receptive or expressive vocabulary skills
So how do we use this information? Should we just have a checklist and if the child presents with more than three of the risk factors, we intervene? It’s complicated. A recent study by Walsh, Christ, and Weber in August 2021 looked at the relationships among the risk factors for persistence in stuttering. While they did not find significant relationships between sex or age at onset and persistence (Eek! That’s different from the last study!), they did find some interesting interactions between the other risk factors that can help SLPs make clinical decisions when it comes to treating preschoolers who stutter. They looked at the relationships between family history, frequency of stuttering-like disfluencies (SLDs), performance on nonword repetition tasks (NRT), and articulation/phonological skills.
In the table below, I’ve summarized the relationships between risk factors that I found to be the most significant when I assess preschoolers who stutter (note, this is a highly-simplified interpretation of the information in the article, please read the full article for more detail):
So how should this impact you, the clinical SLP? First, make sure your assessments are covering all these risk factors. I personally have added molecular analysis of disfluencies to my preschool stuttering assessments so that I can make decisions about whether to treat that are evidence-based. Molecular analysis is basically a breakdown of every moment of stuttering, so that you can calculate the percentages of stuttering-like disfluencies and non-stuttering like disfluencies. It’s incredibly time-consuming, but necessary, because children with a lower frequency of SLDs have a a much lower chance of persistence, regardless of family history.
If there are concerns with articulation skills (from the parent or you), you should certainly include a standardized articulation test in your assessment battery. Walsh et al. point out in their study that a standardized test is not necessary if you, with all your clinical expertise, informally assess the child and find that articulation skills appear to be age-appropriate.
I am also adding a nonword repetition task to my preschool stuttering assessment battery. You can see in the table above that for children who did not have a family history of stuttering, low NRT scores had a significant correlation with persistent stuttering in both the high-SLD and average-SLD groups. Gathering information about nonword repetition skills may help you to make decisions about whether or not to treat a child immediately. Don’t have a nonword repetition task to use? Try this one from Dollaghan and Campbell (1998), although you’ll have to come up with your own norms by giving it to a handful of preschool-aged kids with and without suspected language disorders.
Finally, use your clinical judgement. When it comes to treating preschool stuttering, sensitivity is certainly more important than specificity. That is, it would be better to over-identify children who are likely to persist in stuttering than to under-identify. If you accidentally provide treatment to a child who would have spontaneously recovered, the consequences, if any, will be small and insignificant. Consider the alternative, where you delay treatment for a child who is likely to persist. The consequences could be much greater. Make sure you involve parents in any decision about providing immediate treatment versus delaying treatment. Let them know that there are many factors at play contributing to the likelihood that their child’s stuttering will persist. Use the assessment data you’ve collected and your clinical judgement to provide them with information that will make them feel confident about the decision you make in the end. And if you decide to delay treatment, make sure to monitor the child’s speech, schedule regular check-ins with the parents, and have them contact you if there are any significant changes in fluency.
I love discussing preschool stuttering! If you’re struggling with how to assess or treat preschoolers who stutter, please reach out to me at firstname.lastname@example.org, I’d love to hear from you!
Walsh, B., Christ, S., & Weber, C. (2021). Exploring Relationships Among Risk Factors for Persistence in Early Childhood Stuttering. Journal of Speech, Language, and Hearing Research, 64(8), 2909-2927. https://doi.org/10.1044/2021_JSLHR-21-00034
Singer, C., Hessling, A., Kelly, E., Singer, L., & Jones, R. (2020). Clinical Characteristics Associated with Stuttering Persistence: A Meta-Analysis. Journal of Speech, Language, and Hearing Research, 63(9), 2995-3018. https://doi.org/10.1044/2020_JSLHR-20-00096