Stuttering and Cluttering in Adults

Stuttering interrupts the flow of speech with repeated sounds, stretched sounds and blocks, though the person knows exactly what they want to say; about 1 in 100 adults stutter.⁠^1,2 Cluttering makes speech sound too fast or irregular. There is no cure for stuttering, but speech therapy can reduce it, ease the fear and avoidance around it, and help make cluttered speech easier to follow (see speech therapy for adults).⁠^1,3,4

What is stuttering in adults?

Stuttering is an interruption in the flow of speaking: repetitions of sounds, syllables or words, prolonged sounds, and interruptions known as blocks.⁠^1,4 A person who stutters knows exactly what they want to say but has trouble producing a normal flow of speech.⁠¹ The core signs ASHA lists:

• Repetitions of parts of words, sounds or syllables, or of whole one-syllable words.⁠⁴
• Prolongations: stretching a sound when no emphasis is meant.⁠⁴
• Blocks: silent pauses, or being unable to start a sound.⁠⁴
• Tension or struggle in producing words.⁠⁴

Stuttering varies from day to day and with the situation: speaking to a group or on the phone can make it worse, while singing, reading or speaking in unison may temporarily reduce it.⁠^1,4 Many adults also have secondary behaviors, such as eye blinking, jaw tightening, head nodding or tapping, and some avoid sounds or words, swap words or insert unnecessary words before a feared one.⁠^1,4

What is covert stuttering?

Covert stuttering is when a person hides, or tries to hide, their stuttering through avoidance and escape behaviors, and it can depend on the situation.⁠⁴ Hiding it is associated with more adverse impact and psychological distress, and stuttering less on the surface does not mean less emotional, social or functional impact.⁠⁴ Adults describe a sense of loss of control, lower self-confidence and more social anxiety.⁠⁴ Not every adult who stutters wants to be fluent: some consider stuttering a neurodivergent way of communicating, and some are indifferent to or proud of how they speak.⁠^4,13

How common is stuttering in adults?

• Adults: about 0.96%, or roughly 1 in 100, in a 2025 recalculation that includes stuttering that began in adulthood; ASHA gives 0.81% for adults whose stuttering began in childhood.⁠^2,4
• All ages in the US: roughly 3 million Americans stutter.⁠¹
• Men and women: about four times as many men as women, for example 0.8% of men and 0.2% of women in the German guideline’s figures.⁠^5,14
• From childhood: about 25% of children who stutter continue, and for them it can be lifelong; stuttering in children covers the early years.⁠¹
• Community: fewer than 1% of adults who stutter engage with stuttering communities.⁠²

What is cluttering?

Cluttering is a fluency disorder in which speech is perceived as abnormally fast or irregular, with many disfluencies that are not typical of stuttering, irregular pausing and over-coarticulated speech, where sounds and syllables run together.⁠⁴ Other signs include mazes and frequent topic shifts, unusual rhythm from pauses in odd places, dropped word endings and collapsed syllables.⁠⁴ The measured rate is not always faster than average, but listeners hear it as rapid, and it can be hard to understand.⁠^4,15

Some people who clutter are not aware of it, though many know that others struggle to understand them, and some develop anxiety and avoid speaking.⁠^4,15 It is often diagnosed late, in adolescence or adulthood, and some adults who clutter were first diagnosed with stuttering.⁠⁴ Experts estimate that about a third of people who stutter show some features of cluttering, an estimate ASHA notes rests more on clinical experience than data.⁠⁴ Conditions that often co-occur with it include ADHD, auditory processing disorders, autism, learning disabilities, Tourette’s syndrome and word-finding difficulties.⁠⁴ Its causes are not clear, and no precise prevalence is known.⁠^5,15

Stuttering vs cluttering: what is the difference?

The two can occur together, which is why an SLP assesses both.⁠⁴

What causes stuttering in adults?

For most adults who stutter, it began in childhood. Its causes are thought to be multifactorial, including genetic and neurophysiological factors; environmental factors and speaking demands can make disfluency worse, but emotional problems and parenting style do not cause stuttering.⁠⁴ What research has found:

• Brain differences: brain imaging shows consistent differences between people who stutter and those who do not, and brain lesions that cause stuttering in adulthood map to one network, centered on the left putamen, which suggests that acquired and developmental stuttering share brain anatomy.⁠^1,5,16
• Family: about 60% of people who stutter have a relative who stutters.⁠⁴
• Genes: NIDCD reports four genes linked to stuttering; one study tied it to variations in genes that govern lysosomal metabolism; and a 2025 study of 99,776 people who stuttered and over a million who did not identified 57 regions of the genome, with heritability estimates ranging from 0.42 to 0.84.⁠^1,14,17
• Not the family environment: the environment siblings share plays little or no causal part.⁠⁵

Can stuttering start suddenly in adulthood?

Yes, though it is less common than stuttering that began in childhood, and it has different causes:⁠²

• Brain injury: neurogenic stuttering can follow a stroke, a head injury such as traumatic brain injury, or another brain injury, and also occurs with diseases such as Parkinson’s disease and multiple sclerosis.⁠^1,6 In a study of 319 people after a stroke, 5.3% met the criteria for neurogenic stuttering, and in at least 2.5% it lasted more than six months.⁠¹⁸
• Medicines: a review of case reports found 27 drugs behind 86 episodes of stuttering, 57% of them from antipsychotic drugs, mostly clozapine; when the drug was stopped, stuttering improved or went away in every case, and the authors warn that a drug cause is easily missed.⁠⁶
• Functional (psychogenic) stuttering: new stuttering in an adult who never stuttered can also be a functional neurological disorder, diagnosed from positive clinical signs; stuttering caused by emotional trauma is rare.⁠^1,19,20

Speech that changes suddenly needs emergency care, because sudden trouble speaking is a stroke sign:

What are the signs of stuttering in adults?

Everyone is disfluent at times, and not every disfluency is stuttering.⁠^4,13 The difference, as the CHSA describes it:

Clinicians in Germany treat stuttering on at least 3% of spoken syllables as a threshold, but also evaluate stuttering whatever its frequency when there are long blocks, emotional stress, avoidance or other accompanying signs.⁠⁵ Stress or excitement can bring more stuttering.⁠¹⁵

How is stuttering diagnosed in adults?

A speech-language pathologist (SLP) assesses the extent and impact of the stuttering or cluttering, the likely benefit of treatment and your motivation, and asks about your experience with stuttering, any earlier therapy and why you are seeking help now.⁠⁴ Speech therapy explains what SLPs do. An assessment usually includes:

• Speech samples in several situations, because a single sample can mislead; the German guideline asks for recordings of at least 300 syllables each.⁠^4,5,22
• Counts and timings: the frequency, type and duration of disfluencies, speech rate, intelligibility and secondary behaviors.⁠⁴
• Standard measures: the Stuttering Severity Instrument (SSI-4), which takes 15 to 20 minutes and scores frequency, duration, physical concomitants and naturalness, and the OASES, which looks at the whole experience of stuttering and its effect on quality of life.⁠^5,23,24
• Self-report: questionnaires on thoughts, beliefs, self-stigma and confidence about speaking, and your readiness for change and goals.⁠^4,22
• Covert features: how much you avoid or hide stuttering, which standardized tests can miss.⁠⁴

A panel of experts agreed on six core areas for a full evaluation of adults, including case history forms for the adult and significant others, observation in several speaking situations, and readiness and goals for treatment.⁠²² For cluttering, the SLP checks whether slowing down or pausing more reduces the symptoms.⁠⁴ If an anxiety or other psychological disorder is suspected, the person should be referred for its own evaluation.⁠⁵

Does speech therapy help adults who stutter?

Yes, though not as a cure: there is no cure for stuttering, but a variety of treatments are available.⁠¹ In a review of the adult evidence, including five randomized trials, speech restructuring cut stuttering by 50% to 57% on average, though no study brought it to the level of people who do not stutter, and how long the gains lasted varied.⁠³ ASHA’s summary of published studies reports reductions of 43% to 64% in overall stuttering severity and 66% to 94% in avoidance, and 94% to 100% of adults and adolescents treated would recommend therapy to others.⁠²⁵

Goals are set with you. They can include communicating more easily and effectively, being more accepting and open about stuttering, reducing secondary behaviors and avoidance if they are a burden, and limiting the impact of stuttering on your life.⁠⁴ Fluency may not be a goal at all for some people, and ASHA notes that stuttering itself does not inherently require treatment.⁠⁴

What is fluency shaping, or speech restructuring?

Fluency shaping changes the timing and tension of speech: easy onsets of voice, light contact of the lips and tongue, continuous voicing, prolonged syllables and a slower rate, with pausing as one way to slow down.⁠⁴ The German guideline finds good evidence with large effects for these methods in adolescents and adults, and says they shall be used.⁠⁵ The Camperdown Program is one: in its phase II trial, 16 of 30 adults completed the program, after a mean of 20 hours in the clinic, and showed minimal or no stuttering in everyday situations for up to 12 months, though their own ratings were less positive.⁠²⁶ The approach may change visible stuttering more than covert stuttering, and the techniques can make speech sound less natural, which some people dislike.⁠^4,27

What is stuttering modification therapy?

Stuttering modification aims to reduce physical tension and struggle, so stuttering is easier rather than gone. It moves through identifying what happens in a moment of stuttering, desensitization, modification and carrying it into daily life, using techniques such as the preparatory set, pull-outs and cancellations, practiced first in easy situations and then in harder ones, such as calling a stranger.⁠⁴ The German guideline finds weaker evidence, with intermediate effects, and notes that combining it with speech restructuring is also effective.⁠⁵

Does cognitive behavior therapy help with stuttering?

For anxiety, yes. In a randomized trial of 32 adults, 60% had social phobia; speech restructuring alone did not change it at 12 months, while those who also had cognitive behavior therapy (CBT) no longer had social phobia, though CBT did not improve fluency.⁠⁸ In a later trial of 32 adults, 5 months of an online CBT program added to speech treatment brought clinically significant gains in self-rated stuttering severity and quality of life at 12 months.⁠²⁸ Treating the anxiety alone does not reduce stuttering, and treating the stuttering alone does not reduce the anxiety, so the German guideline asks for both.⁠⁵

What are acceptance and commitment therapy and avoidance reduction therapy?

Acceptance and commitment therapy (ACT) helps people change their relationship with difficult thoughts and feelings, and Avoidance Reduction Therapy for Stuttering (ARTS) has people disclose their stuttering and enter feared speaking situations, to reduce word avoidance and speak more spontaneously.⁠⁴ The evidence is early: a group ACT program of 2-hour weekly sessions for 8 weeks kept its gains at 3 months in 20 adults, and an ACT and fluency program of eight 60- to 90-minute sessions kept them at 3 and 6 months in 29 adults, both without a control group.⁠^29,30

What do reviews of adult stuttering treatment conclude?

• Baxter 2015, 47 papers on adults: about three quarters were at higher risk of bias, no intervention worked for everyone, and 25 papers with 2 or more years of follow-up showed that some fading is likely but gains can last.⁠³¹
• Bothe 2006: the strongest adult programs combine prolonged speech with self-management, response contingencies (feedback on performance) and other supports.⁠³²
• Connery 2021, nine randomized trials with 276 people: no pooled difference between treatment groups and comparison groups, many of which received another active treatment.⁠³³
• The German guideline: effective adult programs start with intensive practice of slowed speech, include group therapy, practice transfer into daily life, aim for natural-sounding speech and include maintenance.⁠⁵

Do devices, apps or medicines help stuttering?

Devices. Altered auditory feedback devices play your voice back slightly changed, so it sounds as if you are speaking in unison with someone; in some people they improve fluency quickly, but how long the effect lasts is not known.⁠¹ A review found that the devices have spread faster than the trials testing them, and that their effect in conversation and everyday situations is not known.⁠³⁴ In 11 adults fitted with one device, the effect seen at fitting was not there across 4 months, though users felt positive about it.⁠⁹ The German guideline says such devices can eliminate stuttering while they are used but should not be routine treatment, and that fluency software belongs inside recommended therapy, supervised by a therapist.⁠⁵

Medicines. The FDA has not approved any drug for stuttering; drugs approved for epilepsy, anxiety or depression have been tried, but their side effects make long-term use difficult.⁠¹ A review of 31 drug studies found none that met more than 3 of 5 quality criteria, and no drug shown in sound studies to halve stuttering or improve its social and emotional effects; the German guideline says medicines shall not be used.⁠^5,35 In a 12-week placebo-controlled trial of ecopipam in 68 adults, stuttering severity improved no more on the drug than on placebo.⁠²³ A placebo-controlled trial of lumateperone in adults is recruiting, with 24 participants planned and primary completion expected July 31, 2027.⁠³⁶

How is cluttering treated?

Mainly by managing rate and building awareness. ASHA lists strategies such as pausing more to slow the rate, stressing long words and word endings, keeping a steady volume through each sentence, and noticing when a listener has not understood, from their reactions.⁠⁴ Fluency shaping techniques such as easy onsets may not help cluttering.⁠⁴ The few studies of cluttering therapy have found the most success with speech restructuring strategies, and slowing down alone does not usually make articulation clearer.⁠⁵

What happens in stuttering therapy, session by session?

There is no standard dose: it depends on the approach and the person, and scheduling, cost and insurance also play a part, so it often comes down to the SLP’s judgment and your needs.⁠⁴ What a course usually involves:

• Goals first: personal goal setting, sometimes with motivational interviewing to build readiness for change.⁠⁴
• Weekly or intensive: programs run weekly, or intensively over 2 to 3 weeks, often with group work; more hours of therapy did not clearly lead to better results for everyone.⁠^5,26,31
• Individual and group sessions: groups add practice with more listeners and a sense of belonging, with less stigma.⁠⁴
• Practice in real life: bringing other people into sessions, outings to stores and businesses, and phone calls, starting with easy situations and moving to harder ones.⁠⁴
• A check at three months: after three months of at least weekly therapy, progress should be visible in at least one goal, or the approach should be revised.⁠⁵
• Maintenance: every approach should include a plan for keeping skills going in daily life and for preventing relapse.⁠⁴

Programs with a set dose include the Camperdown Program (a mean of 20 clinic hours in its phase II trial), group ACT (2 hours a week for 8 weeks) and ACT with fluency work (eight 60- to 90-minute sessions).⁠^26,29,30 Signs that therapy is working include more confidence, disclosing stuttering, less anxiety when communicating and taking part in more conversations.⁠⁴

What helps keep the gains after therapy?

Planning for it. In 89 adults and adolescents after intensive speech restructuring, adding video self-modeling did not lower stuttering at 1 or 6 months, though satisfaction with fluency was 20% better.⁠³⁷ In 228 adults, recovery or relapse in stuttering behaviors happened separately from recovery or relapse in its wider impact, so both are worth tracking.⁠³⁸ Reviews find that some gains fade, but positive outcomes can persist for years.⁠^3,31

How are stuttering and anxiety linked?

Closely, in adults who seek help. In 92 adults seeking stuttering treatment, compared with 920 matched controls, the odds of any anxiety disorder in the past year were six to seven times higher, of social phobia 16 to 34 times higher, and of generalized anxiety disorder four times higher.⁠⁷ In a larger sample of 275 adults who stuttered, 29.8% had social anxiety disorder, and they did not stutter more severely than the others.⁠³⁹ A meta-analysis confirmed substantially raised trait and social anxiety in adults who stutter.⁠⁴⁰ Hiding stuttering is itself linked to more distress.⁠⁴

Depression and suicidal thoughts can occur too: in a study of 140 adults who stutter, recruited through advertising about suicidal ideation, 67.9% reported some suicidal thoughts, and 59 of those 95 linked them to stuttering.⁠⁴¹ SLPs refer people with these thoughts to mental health professionals.⁠⁴ If you are thinking about suicide, call, text or chat 988 for free, confidential support 24 hours a day.⁠⁴²

Because anxiety and stuttering need separate treatment, the German guideline says psychotherapy that does not also address the stuttering should not be the only treatment, and that suspected anxiety disorders should be referred for their own evaluation.⁠⁵

How does stuttering affect work, and what are your rights?

Phone calls, time pressure and colleagues’ attitudes are the usual difficulties at work, and adults who stutter can face discrimination, lower earnings and glass-ceiling effects.⁠⁴ In a US national study in which 261 of 13,564 people stuttered, the earnings gap linked to stuttering exceeded $7,000, and women who stutter were 23% more likely to be underemployed.⁠⁴³ In a survey of 232 adults who stutter, more than 70% believed it lowers the chance of being hired or promoted, and 20% had turned down a job or promotion because of it.⁠⁴⁴ Being more open about stuttering can help people talk about it at work, advocate for themselves and build support.⁠⁴

Is stuttering a disability under the ADA?

It can be. The ADA has no list of covered conditions, but it names speaking and communicating among major life activities, is to be read in favor of broad coverage, covers an episodic impairment if it would substantially limit a major life activity when active, and is judged without regard to learned behavioral or adaptive modifications, such as fluency techniques.⁠^11,12 Section 504 of the Rehabilitation Act also applies at work.⁠⁴ The Job Accommodation Network suggests:

• Interview questions in advance, and an in-person interview in place of a phone interview.⁠¹²
• Email and instant messaging as alternatives to calls.⁠¹²
• A flexible schedule, fluency devices if they help, and job restructuring.⁠¹²

The National Stuttering Association’s program for work offers webinars, practice job interviews and career success profiles.⁠⁴⁵

How should you talk with an adult who stutters?

Focus on what the person says, not how they say it.⁠^13,15 The Job Accommodation Network and ASHA suggest:

• Be patient and listen, and relax and talk as you normally would.⁠¹²
• Do not finish words or sentences, interrupt or speak for the person.⁠^12,13
• Keep natural eye contact.⁠¹²
• Do not tell them to slow down, stop stuttering or think before they speak; it adds tension.⁠¹³
• Never make fun of anyone’s speech.⁠¹³

Looking impatient, or drawing attention to the person’s speech, can bring more stuttering.⁠¹⁵ Partners often share the experience: in one study, people who stutter and their fluent partners reported similar reactions and difficulties, and the authors suggest including partners in treatment.⁠⁴⁶ Self-disclosure, saying “I stutter,” is linked to higher quality of life, and listeners may find a speaker who discloses friendlier and feel more at ease.⁠⁴

Can adults stop stuttering?

Stuttering that lasts into adulthood is usually lifelong, and there is no cure; it can continue past 55, with the full range of behaviors seen in younger adults.⁠^1,47 But adults can change how often and how hard they stutter, and how much it limits them: therapy cuts stuttering by about half on average, and ASHA’s goals for adults include easier communication, more acceptance and openness, and less avoidance.⁠^3,4 Recovery is more than fluency: it goes with more positive feelings, behaviors and thoughts about stuttering.⁠³⁸ Many people find their greatest success through a combination of self-study and therapy.⁠¹

Which conditions are related to stuttering in adults?

Conditions that often occur with stuttering include ADHD, autism, intellectual disability, language or learning disabilities, seizure disorders, social anxiety disorder and speech sound disorders.⁠⁴ Stuttering shares genetic ground with autism, depression and impaired musical rhythm.⁠¹⁴ After a stroke, people with neurogenic stuttering who also had aphasia stuttered more often than those without it.⁠¹⁸ Cluttering and other speech disorders, such as apraxia or articulation and phonological disorders, can each make speech harder to understand, and functional stuttering can occur alongside stroke, epilepsy or traumatic brain injury.⁠^4,19

Other adult speech, language and swallowing problems have their own causes and treatment: dysarthria, the slurred speech of weak muscles; voice disorders; dysphagia; cognitive-communication disorders; and the changes in communication that come with ALS and dementia.

What are common myths about stuttering?

• Myth: stuttering is caused by nerves or emotional trauma. Emotional problems and parenting style do not cause stuttering, and stuttering caused by emotional trauma is rare.⁠^1,4
• Myth: people who stutter are less intelligent. There is no connection between stuttering and intelligence.⁠¹³
• Myth: telling someone to slow down helps. It increases tension; slowing down is a technique taught in therapy, which is different from being told to slow down mid-sentence.⁠^4,13
• Myth: adults cannot improve. Trials show large reductions in stuttering with speech restructuring in adults.⁠^3,5
• Myth: there is a cure. There is none, and the German guideline warns against approaches that promise one without clear treatment objectives.⁠^1,5

How do you find a stuttering specialist near you?

SLPs are the primary providers of stuttering and cluttering treatment, and those who treat adults should be specifically trained to do so.⁠⁴ Board Certified Specialists in Stuttering, Cluttering, and Fluency Disorders (BCS-SCF) hold ASHA’s clinical certificate and have shown advanced knowledge and expertise, though the specialty certification is voluntary.⁠^4,48 Every SLP needs a state license. ASHA’s Certificate of Clinical Competence (CCC-SLP) is a national credential whose holders have met standards that typically go beyond state licensure, and anyone can check an SLP’s certification on ASHA’s site.⁠^49,50

The DrSensory speech therapy directory lists practices by state and city. On a city page, set Care for to Adults and Specialty to Stuttering / fluency. A specialty tag comes from the practice’s own description of its services, not from a credential, so ask how many adults who stutter or clutter the SLP treats and which approaches they use when you call.

Be wary of anyone who promises a cure.⁠⁵ Therapy can also be done online: in a randomized trial of 40 adults, the Camperdown Program by telehealth was as effective at 9 months as face to face and used less clinician time, and ASHA notes that video can be a more or less stressful setting for speaking.⁠^4,10 Medicare covers telehealth from home through December 31, 2027.⁠⁵¹ For support, the National Stuttering Association runs adult chapters for people who stutter, their families and SLPs, and support groups are linked to lower internalized stigma and better psychological well-being.⁠^4,45

Sources

1. National Institute on Deafness and Other Communication Disorders. Stuttering. Page last updated March 6, 2017. Stuttering is “characterized by repetition of sounds, syllables, or words; prolongation of sounds; and interruptions in speech known as blocks”; “An individual who stutters exactly knows what he or she would like to say but has trouble producing a normal flow of speech”; “Roughly 3 million Americans stutter”; “Approximately 75 percent of children recover from stuttering. For the remaining 25 percent who continue to stutter, stuttering can persist as a lifelong communication disorder”. “Recent brain imaging studies have shown consistent differences in those who stutter compared to nonstuttering peers”; NIDCD researchers “have identified four different genes in which mutations are associated with stuttering”; “Neurogenic stuttering may occur after a stroke, head trauma, or other type of brain injury”; “today we know that psychogenic stuttering is rare”. “Although there is currently no cure for stuttering, there are a variety of treatments available”; therapies for teens and adults teach “speaking more slowly, regulating their breathing, or gradually progressing from single-syllable responses to longer words and more complex sentences”; “The U.S. Food and Drug Administration has not approved any drug for the treatment of stuttering”; off-label drugs “often have side effects that make them difficult to use over a long period of time”; of electronic devices, “Additional research is needed to determine how long such effects may last”; “Self-help groups provide a way for people who stutter to find resources and support”. Checked October 7, 2026.
2. Gattie M, Lieven E, Kluk K. Adult stuttering prevalence II: recalculation, subgrouping and estimate of stuttering community engagement. Journal of Fluency Disorders. 2025;83:106086. doi:10.1016/j.jfludis.2024.106086 (PMID 39706110). Recalculation from the strongest prevalence studies: “Adult stuttering prevalence was estimated at 0.96% (95% CI 0.65, 1.44)”, of which overt stuttering comprised “0.53% childhood onset and 0.10% adult onset” and covert stuttering “0.28% childhood onset and 0.05% adult onset”; “Covert stuttering will have been overestimated, and may often be very mild”; “Of adults who stutter, fewer than 1% engage with stuttering communities”.
3. Brignell A, Krahe M, Downes M, Kefalianos E, Reilly S, Morgan AT. A systematic review of interventions for adults who stutter. Journal of Fluency Disorders. 2020;64:105766. doi:10.1016/j.jfludis.2020.105766 (PMID 32438123). “Five RCTS, four registered trials and three systematic reviews met inclusion criteria”; “On average, stuttering frequency was reduced by 50-57 % using speech restructuring approaches”; “No study reduced stuttering to the same level as community controls who don’t stutter”; “Speech restructuring delivered via telehealth was non-inferior to face-to-face intervention”; “degree and maintenance of fluency varied”.
4. American Speech-Language-Hearing Association. Stuttering, Cluttering, and Fluency (Practice Portal). Revised in 2025; the page states that “Acquired neurogenic stuttering and functional fluency disorders are not covered”. “Stuttering is an interruption in the flow of speaking due to disfluencies”; overt signs include “part-word or sound/syllable repetitions”, prolongations and “blocking (i.e., inaudible or silent pauses or inability to initiate sounds)”; “Covert stuttering occurs when a person hides, or attempts to hide, their stuttering by using avoidance and escape behaviors”. Adult prevalence: “0.81% for adults 21 years and older with childhood onset stuttering, comprised of 0.53% overt stuttering and 0.28% covert stuttering”; the male-to-female ratio has been reported “to be as large as 4:1”. Cluttering: “a rate that is perceived to be abnormally rapid and/or irregular”, “an excessive number of nonstuttering-like disfluencies”, “frequent irregular patterns of pausing” and “frequent over-coarticulated speech”; “approximately one third of children and adults who stutter also present with at least some components of cluttering”, though “There are more clinical anecdotes than data to support this statement”. Causes are “multifactorial and include genetic and neurophysiological factors”; “Emotional problems and parenting style do not cause stuttering”; “There is limited research available that identifies the causes of cluttering”. “Adult assessment focuses on determining the extent and impact of the stuttering and/or cluttering, potential treatment benefits, and motivation to participate in treatment”. Treatment: speech modification (fluency shaping) changes “the timing and tension of speech production”; “The goal of stuttering modification strategies typically is to reduce physical tension and/or struggle”; ACT and cognitive behavioral therapy are named as cognitive restructuring; “Participation in support groups has also been linked to lower internalized stigma and higher psychological well-being”; “Self-disclosure has been linked to higher quality of life”; for cluttering, “Speech rate strategies (e.g., increased pausing)”, and “Fluency shaping approaches, such as easy onset or continuous phonation, may not be effective for the treatment of cluttering”. “Stuttering itself does not inherently require remediation”; “determining dosage often comes down to the professional opinion of the SLP and the needs of the individual”. Work: “being on the telephone at work” and “Responding to time pressures for verbal communication with colleagues”. Checked October 7, 2026.
5. Neumann K, Euler HA, Bosshardt HG, Cook S, Sandrieser P, Sommer M. The pathogenesis, assessment and treatment of speech fluency disorders. Deutsches Ärzteblatt International. 2017;114(22-23):383-390. doi:10.3238/arztebl.2017.0383 (PMID 28655373). Summary of the German interdisciplinary evidence- and consensus-based (S3) guideline with a systematic review. “Approximately 1% of children and adolescents, 0.2% of women, and 0.8% of men suffer from stuttering”; heritability “range from 70% to over 80%”. “For adolescents and adults, there is good evidence with high effect sizes (Cohen’s d = 0.75–1.63) for speech restructuring methods such as fluency shaping; weak evidence with intermediate effect sizes for stuttering modification”; “Medication treatments shall not be used (strong negative evidence”; devices that alter auditory feedback “can eliminate stuttering during the period of their use” but “cannot be recommended as routine treatment components”. Assessment uses “samples of at least 300 syllables of connected speech”, “the Stuttering Severity Instrument, fourth edition (SSI-4)” and the OASES. “After three months’ therapy of at least one weekly session, notable improvements should be detectable in one of the therapeutic objectives; otherwise the therapeutic approach should be revised”; “The exclusive treatment of stuttering-associated anxiety disorder does not reduce the frequency of stuttering and exclusive treatment of the speech fluency disorder does not reduce the anxiety disorder”. Acquired neurogenic stuttering “can occur at any age after a brain injury”; psychogenic stuttering “develops usually after puberty acutely as a result of psychotrauma or an underlying psychiatric illness”. Self-help groups are recommended “on the basis of a clinical consensus”. For cluttering, the Predictive Cluttering Inventory “is available for the purpose of screening for cluttering”, and “The few therapeutic studies have shown successes especially for speech restructuring strategies from stuttering therapy”.
6. Nikvarz N, Sabouri S. Drug-induced stuttering: a comprehensive literature review. World Journal of Psychiatry. 2022;12(2):236-263. doi:10.5498/wjp.v12.i2.236 (PMID 35317340). Review of published case reports: “Twenty-seven drugs caused 86 episodes of stuttering in 82 cases”; “The most episodes of DIS were related to antipsychotic drugs (57%), mostly including clozapine”; “In 55.8% of the episodes of DIS, the offending drug was withdrawn to manage stuttering, which resulted in significant improvement or complete relief of stuttering in all cases”. Case reports only, so no rate can be given.
7. Iverach L, O’Brian S, Jones M, Block S, Lincoln M, Harrison E, et al. Prevalence of anxiety disorders among adults seeking speech therapy for stuttering. Journal of Anxiety Disorders. 2009;23(7):928-934. doi:10.1016/j.janxdis.2009.06.003 (PMID 19595561). “92 adults seeking treatment for stuttering, and 920 age- and gender-matched controls”; the stuttering group had “six- to seven-fold increased odds of meeting a 12-month diagnosis of any DSM-IV or ICD-10 anxiety disorder” and “16- to 34-fold increased odds of meeting criteria for DSM-IV or ICD-10 social phobia”.
8. Menzies RG, O’Brian S, Onslow M, Packman A, St Clare T, Block S. An experimental clinical trial of a cognitive-behavior therapy package for chronic stuttering. Journal of Speech, Language, and Hearing Research. 2008;51(6):1451-1464. doi:10.1044/1092-4388(2008/07-0070) (PMID 18664696). “Thirty-two adults with chronic stuttering were randomly allocated” to speech restructuring after a CBT package or speech restructuring alone; “Sixty percent of our cohort were diagnosed with social phobia”; “At follow-up, participants who had received CBT showed no social phobia”, but the CBT “did not improve fluency”, and speech restructuring alone “had no impact on the social phobia of our cohort at 12 months follow-up”.
9. Pollard R, Ellis JB, Finan D, Ramig PR. Effects of the SpeechEasy on objective and perceived aspects of stuttering: a 6-month, phase I clinical trial in naturalistic environments. Journal of Speech, Language, and Hearing Research. 2009;52(2):516-533. doi:10.1044/1092-4388(2008/07-0204) (PMID 18695013). “Eleven adults who stutter participated”, wearing the in-ear device in daily life: “a statistically significant effect of the SpeechEasy immediately postfitting but no treatment effect across 4 months’ time”; “Device use coincided more so with positive subjective impressions than with measurable fluency improvement”.
10. Carey B, O’Brian S, Onslow M, Block S, Jones M, Packman A. Randomized controlled non-inferiority trial of a telehealth treatment for chronic stuttering: the Camperdown Program. International Journal of Language & Communication Disorders. 2010;45(1):108-120. doi:10.3109/13682820902763944 (PMID 19424889). “Forty participants who presented to a university speech clinic were randomized: 20 to the telehealth arm and 20 to the face-to-face arm”; “There was no statistically or clinically significant difference in %SS between the two groups at 9 months post-randomization”; “the telehealth group used statistically less contact time (221 min) on average than the face-to-face group”. Australian university clinic; small trial.
11. U.S. Department of Justice. Americans with Disabilities Act of 1990, As Amended (ADA.gov). “major life activities include, but are not limited to” … “speaking, breathing, learning, reading, concentrating, thinking, communicating, and working”; the definition “shall be construed in favor of broad coverage of individuals”; “An impairment that is episodic or in remission is a disability if it would substantially limit a major life activity when active”; substantial limitation is judged without regard to mitigating measures such as “learned behavioral or adaptive neurological modifications”. The statute names no condition, stuttering included; coverage is decided person by person. Checked October 7, 2026.
12. Job Accommodation Network. Stuttering (A to Z of disabilities and accommodations). “Stuttering is not caused by an emotional or nervous disorder”; “The ADA does not contain a definitive list of medical conditions that constitute disabilities”; for employers: “Do not complete words or sentences for the individual”, “focus on the content of communication rather than the delivery of the communication”, “Provide interview questions in advance if possible” and “Consider offering a personal interview as an alternative to a phone interview”; for the employee: “Use electronic communication options such as e-mail and instant messaging”. Accommodation ideas listed include a flexible schedule, fluency devices and job restructuring. Checked October 7, 2026.
13. American Speech-Language-Hearing Association. The Facts About Stuttering. Myths and facts: “There is not a connection between stuttering and intelligence”; “Don’t interrupt or try to speak for another person”; telling someone to slow down or stop stuttering: “Statements like these increase tension and negative reactions. Pay attention to what a person says and not how they say it”; “Some people who stutter think of their speech as merely a different way of talking”. SLPs can help people “Stutter in an easier way with less tension”, “Feel better about speaking” and “Improve overall communication”. Checked October 7, 2026.
14. Polikowsky HG, Scartozzi AC, Shaw DM, Pruett DG, Chen HH, Petty LE, et al. Large-scale genome-wide analyses of stuttering. Nature Genetics. 2025;57(8):1835-1847. doi:10.1038/s41588-025-02267-2 (PMID 40721530). Genome-wide analyses of 23andMe participants who answered a survey question about ever having had a stammer or stutter (“99,776 cases and 1,023,243 controls), identifying 57 unique loci”), validated in two independent datasets; “heritability estimates ranging from 0.42 to 0.84” in earlier family and twin studies; stuttering is “substantially more common in males than females in adolescent and adult populations (approximately 4:1)”; “genetic similarity of stuttering with autism, depression and impaired musical rhythm”. Limit: stuttering status was self-reported.
15. Communication Health Support Association (powered by the American Speech-Language-Hearing Association). Stuttering and Cluttering. “People who stutter usually have more—and different types of—disfluencies than other people”; “Stress or excitement can lead to more stuttering”; “People who clutter may speak very quickly and be difficult to understand”; a person who stutters “may have small differences in the way their brain works during speech”; things that may cause more stuttering include “appearing impatient with the person who stutters” and “bringing attention to the speech of a person who stutters”; “The main way people can help is to focus on what a person says, rather than how they say it”; “The causes of cluttering aren’t clear”. Checked October 7, 2026.
16. Theys C, Jaakkola E, Melzer TR, De Nil LF, Guenther FH, Cohen AL, et al. Localization of stuttering based on causal brain lesions. Brain. 2024;147(6):2203-2213. doi:10.1093/brain/awae059 (PMID 38797521). Lesion network mapping in two stroke datasets (20 published cases; a clinical cohort of 20) and 20 adults with persistent developmental stuttering: “lesions causing acquired neurogenic stuttering map to a common brain network, centred to the left putamen, claustrum and amygdalostriatal transition area”, and the association with symptom severity in developmental stuttering “suggests a shared neuroanatomy across aetiologies”.
17. Kang C, Riazuddin S, Mundorff J, Krasnewich D, Friedman P, Mullikin JC, et al. Mutations in the lysosomal enzyme-targeting pathway and persistent stuttering. New England Journal of Medicine. 2010;362(8):677-685. doi:10.1056/NEJMoa0902630 (PMID 20147709). NIDCD intramural study of Pakistani families and unrelated cases and controls: mutations in GNPTAB, GNPTG and NAGPA were found in people who stutter but not in controls; “Susceptibility to nonsyndromic stuttering is associated with variations in genes governing lysosomal metabolism”.
18. Theys C, van Wieringen A, Sunaert S, Thijs V, De Nil LF. A one year prospective study of neurogenic stuttering following stroke: incidence and co-occurring disorders. Journal of Communication Disorders. 2011;44(6):678-687. doi:10.1016/j.jcomdis.2011.06.001 (PMID 21807377). Prospective study of 319 people after stroke: “17 of 319 participants (5.3%; 95% CI, 3.2-8.3) met the criteria for neurogenic stuttering”; “Stuttering persisted in at least 2.5% (95% CI, 1.1-4.7) for more than six months following the stroke”; “Participants with comorbid aphasia presented with a significantly higher frequency of stuttering”.
19. Baker J, Barnett C, Cavalli L, Dietrich M, Dixon L, Duffy JR, et al. Management of functional communication, swallowing, cough and related disorders: consensus recommendations for speech and language therapy. Journal of Neurology, Neurosurgery, and Psychiatry. 2021;92(10):1112-1125. doi:10.1136/jnnp-2021-326767 (PMID 34210802). International expert consensus. “Functional stuttering is distinguished from developmental or neurogenic stuttering by new onset in adulthood (without prior developmental speech output difficulties)”, among other features; “FND should be diagnosed on the basis of positive clinical features”; “Although positive outcomes have been reported in case studies of treatment of functional stuttering in adults, it remains unclear what elements of these treatments explain their effectiveness”.
20. MedlinePlus Medical Encyclopedia (U.S. National Library of Medicine). Stuttering. Review date January 1, 2026; written mainly about children. “There is also evidence that stuttering may be a result of brain injuries, such as stroke or traumatic brain injuries”; “In rare cases, stuttering is caused by emotional trauma (called psychogenic stuttering)”; “Some people who stutter find that they do not stutter when they read aloud or sing”; “Taking medicine has not been shown to be helpful for stuttering”; “It is not clear whether electronic devices help with stuttering”. Checked October 7, 2026.
21. Centers for Disease Control and Prevention. Signs and symptoms of stroke (May 19, 2026). Signs include “Sudden confusion, trouble speaking, or difficulty understanding speech”; “Call 9-1-1 right away if you or someone else has any of these symptoms”; in the B.E. F.A.S.T. test for speech, “Ask the person to repeat a simple phrase. Is the speech slurred or strange?”; “The stroke treatments that work best are available only if the stroke is recognized and diagnosed within 3 hours of the first symptoms”; “Note the time when any symptoms first appear”; “Do not drive to the hospital or let someone else drive you”; a TIA “is a sign of a serious condition that will not go away without medical help”, so “tell a health care team about the symptoms right away.” Checked October 7, 2026.
22. Brundage SB, Ratner NB, Boyle MP, Eggers K, Everard R, Franken MC, et al. Consensus guidelines for the assessments of individuals who stutter across the lifespan. American Journal of Speech-Language Pathology. 2021;30(6):2379-2393. doi:10.1044/2021_AJSLP-21-00107 (PMID 34516299). Twelve experts reached consensus on “Six core areas” of a stuttering evaluation: background, development, speech fluency, the speaker’s reactions, reactions of others, and adverse impact. For adults: “Case history forms for the adult and significant others, as appropriate” and “Observation of the adult’s speech in various speaking situations”; “it is important to obtain multiple speech samples across speaking tasks and settings”. Example adult measures include the Stuttering Severity Instrument, the OASES, the “Unhelpful Thoughts and Beliefs about Stuttering” scale and the “Wright-Ayer Stuttering Self-Rating Profile”; “no one procedure for assessing speech fluency and stuttering behavior was preferred by the majority of respondents”.
23. ClinicalTrials.gov. Effects of Ecopipam or Placebo in Adults With Stuttering (Speak Freely) (NCT04492956; sponsor Emalex Biosciences; completed, results posted). 68 adults enrolled; ecopipam or “Matching placebo tablets for daily, oral administration for 12 weeks”. Primary outcome, the Stuttering Severity Instrument, 4th Edition (SSI-4), which “takes 15-20 minutes to complete” and scores frequency, duration, physical concomitants and naturalness. Mean change at 12 weeks was −1.5 points (SD 5.8; 33 analyzed) on ecopipam and −1.8 points (SD 3.04; 31 analyzed) on placebo: no advantage for the drug on the primary outcome. Checked October 7, 2026.
24. Yaruss JS, Quesal RW. Overall Assessment of the Speaker’s Experience of Stuttering (OASES): documenting multiple outcomes in stuttering treatment. Journal of Fluency Disorders. 2006;31(2):90-115. doi:10.1016/j.jfludis.2006.02.002 (PMID 16620945). The OASES, built on the WHO ICF, “collects information about the totality of the stuttering disorder”, including “affective, behavioral, and cognitive reactions to stuttering”, “functional communication difficulties”, and the “impact of stuttering on the speaker’s quality of life”.
25. American Speech-Language-Hearing Association. The Value of Speech-Language Pathology Services for Adults and Adolescents Who Stutter (fact sheet, last updated May 2025). ASHA’s compilation of ranges across separate published studies (Camperdown, ISTAR, CBT and other programs), not one trial: “adults and adolescents who stutter experience a 43%–64% reduction in overall stuttering severity”, “A 54%–94% reduction in stuttering frequency, with lasting improvements at 1- to 5-year follow-up”, and “A 66%–94% reduction in avoidance of stuttering”; “94%–100% of adults and adolescents who receive SLP treatment for stuttering would recommend it to others”. Checked October 7, 2026.
26. O’Brian S, Onslow M, Cream A, Packman A. The Camperdown Program: outcomes of a new prolonged-speech treatment model. Journal of Speech, Language, and Hearing Research. 2003;46(4):933-946. doi:10.1044/1092-4388(2003/073) (PMID 12959471). Phase II trial without a control group: “Thirty participants were initially enrolled in the trial. Final outcome data are presented for the 16 participants who completed all trial requirements”; they “showed minimal or no stuttering in everyday speaking situations for up to 12 months after entering the maintenance program”, but “Although self-report data generally confirmed the speech data, the results were not as positive”; “The present outcomes were achieved in a mean of 20 hours of clinic attendance per participant”, fewer than programs “that run intensively over 2-3 weeks”.
27. Laiho A, Elovaara H, Kaisamatti K, Luhtalampi K, Talaskivi L, Pohja S, et al. Stuttering interventions for children, adolescents, and adults: a systematic review as a part of clinical guidelines. Journal of Communication Disorders. 2022;99:106242. doi:10.1016/j.jcomdis.2022.106242 (PMID 35751980). Systematic review for Finnish clinical guidelines: 38 papers of acceptable quality; there is “some evidence about adults”; “holistic treatments may influence speech fluency and overall experience of stuttering behavior”; “Speech restructuring treatments may have a positive effect on overt characteristics of stuttering, but not on covert stuttering behavior”.
28. Menzies R, O’Brian S, Packman A, Jones M, Helgadóttir FD, Onslow M. Supplementing stuttering treatment with online cognitive behavior therapy: an experimental trial. Journal of Communication Disorders. 2019;80:81-91. doi:10.1016/j.jcomdis.2019.04.003 (PMID 31100535). “Participants were 32 adults seeking treatment for stuttering”, randomized; both arms had speech restructuring and “The experimental arm also received 5 months access to iGlebe”, an internet CBT program; “at 12 months post-randomization, iGlebe added clinically significant improvements to self-reported stuttering severity and quality of life”. Developed and tested by the same team.
29. Beilby JM, Byrnes ML, Yaruss JS. Acceptance and Commitment Therapy for adults who stutter: psychosocial adjustment and speech fluency. Journal of Fluency Disorders. 2012;37(4):289-299. doi:10.1016/j.jfludis.2012.05.003 (PMID 23218212). Group ACT program for 20 adults, no comparison group described: “The program consisted of 2-h therapeutic sessions conducted weekly for eight consecutive weeks”; improvements in psychosocial functioning and “overall speech fluency”; “Follow-up data collected at three months post-treatment revealed that therapeutic gains were successfully maintained over time”.
30. Hart AK, Breen LJ, Hennessey NW, Beilby JM. Evaluation of an integrated fluency and Acceptance and Commitment Therapy intervention for adolescents and adults who stutter. Journal of Speech, Language, and Hearing Research. 2024;67(4):1003-1019. doi:10.1044/2023_JSLHR-23-00252 (PMID 38358941). “Twenty-nine AWS participated in the feasibility trial”; “As this was a feasibility study, no control group was included”; delivered by two SLPs “over eight 60- to 90-min sessions”; improvements in self-efficacy, psychosocial functioning and stuttered speech frequency, and “Intervention gains for all variables of interest were maintained 3 and 6 months post-intervention”.
31. Baxter S, Johnson M, Blank L, Cantrell A, Brumfitt S, Enderby P, et al. The state of the art in non-pharmacological interventions for developmental stuttering. Part 1: a systematic review of effectiveness. International Journal of Language & Communication Disorders. 2015;50(5):676-718. doi:10.1111/1460-6984.12171 (PMID 26123259). 112 papers from 1990 onward, of which “47 papers described interventions for adults who stutter”; “around three-quarters of the studies rated as being at higher risk of bias”; most types of intervention helped at least some people, but “any intervention would not be successful for all who received it”; it found no clear evidence that more hours of treatment for all participants led to better outcomes; the feedback and technology group was the only one “where effects seemed of shorter term duration”.
32. Bothe AK, Davidow JH, Bramlett RE, Ingham RJ. Stuttering treatment research 1970-2005: I. Systematic review incorporating trial quality assessment of behavioral, cognitive, and related approaches. American Journal of Speech-Language Pathology. 2006;15(4):321-341. doi:10.1044/1058-0360(2006/031) (PMID 17102144). “Multiple readers reviewed 162 articles published between 1970 and 2005”, of which 39 met the quality criterion; “The most powerful treatments for adults, with respect to both speech outcomes and social, emotional, or cognitive outcomes, appear to combine variants of prolonged speech, self-management, response contingencies, and other infrastructural variables”.
33. Connery A, Galvin R, McCurtin A. Effectiveness of nonpharmacological stuttering interventions on communication and psychosocial functioning in adults: a systematic review and meta-analysis of randomized controlled trials. Journal of Evidence-Based Medicine. 2021;14(1):17-26. doi:10.1111/jebm.12408 (PMID 33242235). “nine randomized controlled trials, comprising 276 participants”; the meta-analysis found “no significant pooled difference between intervention and comparator groups in improving communication and psychosocial functioning”. Several of the trials compared one active treatment with another, so this is not evidence that therapy fails.
34. Lincoln M, Packman A, Onslow M. Altered auditory feedback and the treatment of stuttering: a review. Journal of Fluency Disorders. 2006;31(2):71-89. doi:10.1016/j.jfludis.2006.04.001 (PMID 16750562). Ten-year review of altered auditory feedback (AAF): “critical knowledge about the effect of AAF during conversational speech and in everyday speaking situations is missing”; “In general device development and availability has occurred at a faster pace than clinical trials research”.
35. Bothe AK, Davidow JH, Bramlett RE, Franic DM, Ingham RJ. Stuttering treatment research 1970-2005: II. Systematic review incorporating trial quality assessment of pharmacological approaches. American Journal of Speech-Language Pathology. 2006;15(4):342-352. doi:10.1044/1058-0360(2006/032) (PMID 17102145). “None of the 31 articles met more than 3 of the 5 methodological criteria”; “None of the pharmacological agents tested for stuttering have been shown in methodologically sound reports to improve stuttering frequency to below 5%, to reduce stuttering by at least half, or to improve relevant social, emotional, or cognitive variables”.
36. ClinicalTrials.gov. Lumateperone in the Treatment of Stuttering, Childhood Onset Fluency Disorder (NCT07734103; sponsor CSTrials Inc.; recruiting). “This is a double-blind, placebo-controlled trial of Lumateperone in adults who suffer from developmental stuttering”; “We anticipate screening a total of 30 subjects in anticipation of enrolling 24 suitable subjects for the trial”; Phase 2, started April 18, 2026, primary completion estimated July 31, 2027. Checked October 7, 2026.
37. Cream A, O’Brian S, Jones M, Block S, Harrison E, Lincoln M, et al. Randomized controlled trial of video self-modeling following speech restructuring treatment for stuttering. Journal of Speech, Language, and Hearing Research. 2010;53(4):887-897. doi:10.1044/1092-4388(2009/09-0080) (PMID 20029053). Maintenance trial: “Participants were 89 adults and adolescents who undertook intensive speech restructuring treatment”; those who watched stutter-free videos of themselves daily for a month did not stutter less (“The addition of VSM did not improve speech outcomes”), but at 6 months their “satisfaction with speech fluency was 20% better” than controls’.
38. Tichenor SE, Yaruss JS. Recovery and relapse: perspectives from adults who stutter. Journal of Speech, Language, and Hearing Research. 2020;63(7):2162-2176. doi:10.1044/2020_JSLHR-20-00010 (PMID 32598208). Mixed-methods survey of 228 adults who stutter: “Recovery or relapse from stuttering behaviors can occur independently from recovery or relapse from the broader adverse impact related to the condition”.
39. Iverach L, Jones M, Lowe R, O’Brian S, Menzies RG, Packman A, et al. Comparison of adults who stutter with and without social anxiety disorder. Journal of Fluency Disorders. 2018;56:55-68. doi:10.1016/j.jfludis.2018.03.001 (PMID 29602052). “Participants were 275 adults who stuttered (18-80 years)” about to start speech treatment; social anxiety disorder in “n = 82, 29.8%”; that group “did not demonstrate significantly higher self-reported stuttering severity or percentage of syllables stuttered” but had more avoidance and psychological problems; “These findings pertain to a clinical sample”.
40. Craig A, Tran Y. Trait and social anxiety in adults with chronic stuttering: conclusions following meta-analysis. Journal of Fluency Disorders. 2014;40:35-43. doi:10.1016/j.jfludis.2014.01.001 (PMID 24929465). Systematic review and meta-analyses: “adults with chronic stuttering do have substantially elevated trait and social anxiety”; “The overall effect size for trait and social anxiety was calculated to be .57 and .82, respectively”.
41. Tichenor SE, Palasik S, Yaruss JS. Understanding the broader impact of stuttering: suicidal ideation. American Journal of Speech-Language Pathology. 2023;32(5):2087-2110. doi:10.1044/2023_AJSLP-23-00007 (PMID 37473446). “One hundred forty adults who stutter completed the Suicide Behavior Questionnaire–Revised”; 95 of them reported at least some suicidal ideation (“out of 140 participants, 67.9%”), and 59 of those 95 felt it was related to their stuttering; higher OASES scores predicted more ideation. Limit: “recruitment for this study was accomplished primarily by advertising the study as focusing specifically on suicidal ideation”.
42. Substance Abuse and Mental Health Services Administration. 988 Suicide & Crisis Lifeline. “988 offers 24/7 judgment-free support for mental health, substance use, and more”; people can call, text or chat 988; the Lifeline provides “24/7, free and confidential support to people in suicidal crisis or emotional distress”. Checked October 9, 2026.
43. Gerlach H, Totty E, Subramanian A, Zebrowski P. Stuttering and labor market outcomes in the United States. Journal of Speech, Language, and Hearing Research. 2018;61(7):1649-1663. doi:10.1044/2018_JSLHR-S-17-0353 (PMID 29933430). National Longitudinal Study of Adolescent to Adult Health: of 13,564 respondents, “261 people indicated that they stutter”; “the deficit in earnings associated with stuttering exceeded $7,000” a year after controls for demographics and comorbidity; “Females who stutter were also 23% more likely to be underemployed than females who do not stutter”; “discrimination may have contributed to the earnings gap”.
44. Klein JF, Hood SB. The impact of stuttering on employment opportunities and job performance. Journal of Fluency Disorders. 2004;29(4):255-273. doi:10.1016/j.jfludis.2004.08.001 (PMID 15639081). Survey “completed by 232 people who stutter, age 18 years or older”: “more than 70% of people who stutter agreed that stuttering decreases one’s chances of being hired or promoted”, and “20% had actually turned down a job or promotion because of their stuttering”. Self-report from 2004.
45. National Stuttering Association. Stuttering Support for Adults. “NSA Adult Chapters are designed for adults who stutter (ages 18+), parents, significant others, friends of stutterers, and speech-language pathologists (SLPs)”; its We Stutter@Work program offers “webinars, practice job interviews, and career success profiles”. Checked October 7, 2026.
46. Beilby JM, Byrnes ML, Meagher EL, Yaruss JS. The impact of stuttering on adults who stutter and their partners. Journal of Fluency Disorders. 2013;38(1):14-29. doi:10.1016/j.jfludis.2012.12.001 (PMID 23540910). Couples study (interviews, OASES and SF-36): “people who stutter and their fluent partners reported similar experiences in reactions to stuttering and perceived difficulties in communication”; the authors support a program “that includes the fluent partner as an agent of change in their treatment”.
47. Bricker-Katz G, Lincoln M, McCabe P. The persistence of stuttering behaviours in older people. Disability and Rehabilitation. 2009;31(8):646-658. doi:10.1080/09638280802306299 (PMID 19105057). Speech samples from “16 people over the age of 55 years who self-reported stuttering into adulthood”: those who still stuttered “evidenced the full range of stuttering behaviours seen in younger adults”; “Stuttering is a disorder that may persist for some beyond 55 years of age”.
48. American Speech-Language-Hearing Association. ASHA clinical specialty certification. A Board Certified Specialist (BCS) has demonstrated advanced knowledge and skills in an area; “Specialty certification is not required to practice in any area within the Audiology or Speech-Language Pathology Scopes of Practice”; “Specialty certification is currently available through” five boards: the “American Audiology Board of Intraoperative Monitoring”, the “American Board of Augmentative and Alternative Communication”, the “American Board of Child Language and Language Disorders”, the “American Board of Fluency and Fluency Disorders” and the “American Board of Swallowing and Swallowing Disorders.” Checked October 7, 2026.
49. American Speech-Language-Hearing Association. Information about ASHA certification. The CCC is “a nationally recognized professional credential that represents a level of excellence in the field”; holders “have voluntarily met rigorous academic and professional standards, typically going beyond the minimum requirements for state licensure.” Checked October 7, 2026.
50. American Speech-Language-Hearing Association. Audiology and speech-language pathology certification. ASHA’s public tool lets anyone “Verify the status of an individual’s Certificate of Clinical Competence in Audiology (CCC-A) or Speech-Language Pathology (CCC-SLP).” Checked October 7, 2026.
51. Centers for Medicare & Medicaid Services. Telehealth (Medicare.gov). “Through December 31, 2027, Medicare covers telehealth services that you can get from anywhere in the U.S., including your home”; the examples listed include speech therapy, cognitive assessments and “Caregiver training services”; after the Part B deductible you pay 20% of the Medicare-approved amount, and “For most telehealth services, you’ll pay the same amount that you would if you got the services in person”; Medicare Advantage plans “may offer more telehealth benefits than the basic coverage in Original Medicare.” Checked October 7, 2026.
52. Boyle MP. Psychological characteristics and perceptions of stuttering of adults who stutter with and without support group experience. Journal of Fluency Disorders. 2013;38(4):368-381. doi:10.1016/j.jfludis.2013.09.001 (PMID 24331244). Web survey of “279 adults who stutter recruited from the National Stuttering Association and Board Recognized Specialists in Fluency Disorders”: “Participants with support group experience as a whole demonstrated lower internalized stigma”. A one-time comparison of self-selected groups, so it cannot show the groups caused the difference.

Medical disclaimer. This page is for general educational purposes and does not constitute medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider about your individual situation.