Assessment will usually include an interview with the child’s caregiver, observation of the child in an unstructured setting, a hearing test, and standardized tests of language and nonverbal ability. There is a wide range of language assessments in English. Some are restricted for use by speech and language professionals (therapists or SALTs in the UK, speech-language pathologists, SLPs, in the US and Australia).

A commonly used test battery for diagnosis of SLI is the Clinical Evaluation of Language Fundamentals (CELF).

Assessments that can be completed by a parent or teacher can be useful to identify children who may require more in-depth evaluation.

The Grammar and Phonology Screening (GAPS) test is a quick (ten minute) simple and accurate screening test developed and standardized in the UK. It is suitable for children from 3;4 to 6;8 years;months and can be administered by professionals and non-professionals (including parents) alike, and has been demonstrated to be highly accurate (98% accuracy) in identifying impaired children who need specialist help vs non-impaired children. This makes it potentially a feasible test for widespread screening.

The Children’s Communication Checklist (CCC–2) is a parent questionnaire suitable for testing language skills in school-aged children.

Informal assessments, such as language samples, may also be used. This procedure is useful when the normative sample of a given test is inappropriate for a given child, for instance, if the child is bilingual and the sample was of monolingual children. It is also an ecologically valid measure of all aspects of language (e.g. semantics, syntax, pragmatics, etc.).

To complete a language sample, the SLP will spend about 15 minutes talking with the child. The sample may be of a conversation (Hadley, 1998), or narrative retell. In a narrative language sample, the SLP will tell the child a story using a wordless picture book (e.g. "Frog Where Are You?", Mayer, 1969), then ask the child to use the pictures and tell the story back.

Language samples are typically transcribed using computer software such as the Systematic Analysis of Language Software (SALT, Miller et al. 2012), and then analyzed. For example, the SLP might look for whether the child introduces characters to their story or jumps right in, whether the events follow a logical order, and whether the narrative includes a main idea or theme and supporting details.

Assessment will usually include an interview with the child’s caregiver, observation of the child in an unstructured setting, a hearing test, and standardized tests of language. There is a wide range of language assessments in English. Some are restricted for use by experts in speech-language pathology: speech and language therapists (SaLTs/SLTs) in the UK, speech-language pathologists (SLPs) in the US and Australia. A commonly used test battery for diagnosis of DLD is the Clinical Evaluation of Language Fundamentals (CELF).

Assessments that can be completed by a parent or teacher can be useful to identify children who may require more in-depth evaluation. The Children’s Communication Checklist (CCC–2) is a parent questionnaire suitable for assessing everyday use of language in children aged 4 years and above who can speak in sentences.

Informal assessments, such as language samples, are often used by speech-language therapists/pathologists to complement formal testing and give an indication of the child's language in a more naturalistic context. A language sample may be of a conversation or narrative retell. In a narrative language sample, an adult may tell the child a story using a wordless picture book (e.g. Frog Where Are You?, Mayer, 1969), then ask the child to use the pictures and tell the story back. Language samples can be transcribed using computer software such as the Systematic Analysis of Language Software, and then analyzed for a range of features: e.g., the grammatical complexity of the child's utterances, whether the child introduces characters to their story or jumps right in, whether the events follow a logical order, and whether the narrative includes a main idea or theme and supporting details.

Developmental Verbal Dyspraxia can be diagnosed by a speech language pathologist (SLP) through specific exams that measure oral mechanisms of speech. The oral mechanisms exam involves tasks such as pursing lips, blowing, licking lips, elevating the tongue, and also involves an examination of the mouth. A complete exam also involves observation of the patient eating and talking. Tests such as the Kaufman Speech Praxis test, a more formal examination, are also used in diagnosis.

A differential diagnosis of DVD/CAS is often not possible for children under the age of 2 years old. Even when children are between 2–3 years, a clear diagnosis cannot always occur, because at this age, they may still be unable to focus on, or cooperate with, diagnostic testing.

Epidemiological surveys, in the US and Canada, estimated the prevalence of SLI in 5-year-olds at around 7 percent. However, neither study adopted the stringent 'discrepancy' criteria of the Diagnostic and Statistical Manual of Mental Disorders or ICD-10; SLI was diagnosed if the child scored below cut-off on standardized language tests, but had a nonverbal IQ of 90 or above and no other exclusionary criteria.

1. SCAN is the most common tool for diagnosing APD, and it also standardized. It is composed for four subsets: discrimination of monaurally presented single words against background noise, acoustically degraded single words, dichotically presented single words, sentence stimuli. Different versions of the test are used depending on the age of the patient.

2. Random Gap Detection Test (RGDT) is also a standardized test. It assesses an individual’s gap detection threshold of tones and white noise. The exam includes stimuli at four different frequencies (500, 1000, 2000, and 4000 Hz) and white noise clicks of 50 ms duration. It is a useful test because it provides an index of auditory temporal resolution. In children, an overall gap detection threshold greater than 20 ms means they have failed.

3. Gaps in Noise Test (GIN) also measures temporal resolution by testing the patient's gap detection threshold in white noise.

4. Pitch Patterns Sequence Test (PPT) and Duration Patterns Sequence Test (DPT) measure auditory pattern identification. The PPS has s series of three tones presented at either of two pitches (high or low). Meanwhile, the DPS has a series of three tones that vary in duration rather than pitch (long or short). Patients are then asked to describe the pattern of pitches presented.

DLD is defined purely in behavioural terms: there is no biological test. There are three points that need to be met for a diagnosis of DLD:

1. The child has language difficulties that create obstacles to communication or learning in everyday life,

2. The child's language problems are unlikely to resolve by five years of age, and

3. The problems are not associated with a known biomedical condition such as brain injury, neurodegenerative conditions, genetic conditions or chromosome disorders such as Down Syndrome, sensorineural hearing loss, or Autism Spectrum Disorder or Intellectual Disability.

For research and epidemiological purposes, specific cutoffs on language assessments have been used to document the first criterion. Tomblin et al. proposed the EpiSLI criterion, based on five composite scores representing performance in three domains of language (vocabulary, grammar, and narration) and two modalities (comprehension and production). Children scoring in the lowest 10% on two or more composite scores are identified as having language disorder.

The second criterion, persistence of language problems, can be difficult to judge in a young child, but longitudinal studies have shown that difficulties are less likely to resolve for children who have poor language comprehension, rather than difficulties confined to expressive language. In addition, children with isolated difficulties in just one of the areas noted under 'subtypes' tend to make better progress than those whose language is impaired in several areas.

The third criterion specifies that DLD is used for children whose language disorder is not part of another biomedical condition, such as a genetic syndrome, a sensorineural hearing loss, neurological disease, Autism Spectrum Disorder or Intellectual Disability – these were termed 'differentiating conditions' by the CATALISE panel. Language disorders occurring with these conditions need to be assessed and children offered appropriate intervention, but a terminological distinction is made so that these cases would be diagnosed as Language Disorder associated with ___, with the main diagnosis being specified: e.g. "Language Disorder associated with Autism Spectrum Disorder." The reasoning behind these diagnostic distinctions is discussed further by Bishop (2017).

There are tests that can indicate with high probability whether a person is a dyslexic. If diagnostic testing indicates that a person may be dyslexic, such tests are often followed up with a full diagnostic assessment to determine the extent and nature of the disorder. Tests can be administered by a teacher or computer. Some test results indicate how to carry out teaching strategies.

Dyslexic children require special instruction for word analysis and spelling from an early age. While there are fonts that may help people with dyslexia better understand writing, this might simply be due to the added spacing between words. The prognosis, generally speaking, is positive for individuals who are identified in childhood and receive support from friends and family.

It has been discovered that APD and ADHD present overlapping symptoms. Below is a ranked order of behavioral symptoms that are most frequently observed in each disorder. Professionals evaluated the overlap of symptoms between the two disorders. The order below is of symptoms that are almost always observed. This chart proves that although the symptoms listed are different, it is easy to get confused between many of them.

There is a high rate of co-occurrence between AD/HD and CAPD. Research shows that 84% of children with APD have confirmed or suspected ADHD. Co-occurrence between ADHD and APD is 41% for children with confirmed diagnosis of ADHD, and 43% for children suspected of having ADHD.

Many normed assessments can be used in evaluating skills in the primary academic domains: reading, including word recognition, fluency, and comprehension; mathematics, including computation and problem solving; and written expression, including handwriting, spelling and composition.

The most commonly used comprehensive achievement tests include the Woodcock-Johnson IV (WJ IV), Wechsler Individual Achievement Test II (WIAT II), the Wide Range Achievement Test III (WRAT III), and the Stanford Achievement Test–10th edition. These tests include measures of many academic domains that are reliable in identifying areas of difficulty.

In the reading domain, there are also specialized tests that can be used to obtain details about specific reading deficits. Assessments that measure multiple domains of reading include Gray's Diagnostic Reading Tests–2nd edition (GDRT II) and the Stanford Diagnostic Reading Assessment. Assessments that measure reading subskills include the Gray Oral Reading Test IV – Fourth Edition (GORT IV), Gray Silent Reading Test, Comprehensive Test of Phonological Processing (CTOPP), Tests of Oral Reading and Comprehension Skills (TORCS), Test of Reading Comprehension 3 (TORC-3), Test of Word Reading Efficiency (TOWRE), and the Test of Reading Fluency. A more comprehensive list of reading assessments may be obtained from the Southwest Educational Development Laboratory.

The purpose of assessment is to determine what is needed for intervention, which also requires consideration of contextual variables and whether there are comorbid disorders that must also be identified and treated, such as behavioral issues or language delays. These contextual variables are often assessed using parent and teacher questionnaire forms that rate the students' behaviors and compares them to standardized norms.

However, caution should be made when suspecting the person with a learning disability may also have dementia, especially as people with Down's syndrome may have the neuroanatomical profile but not the associated clinical signs and symptoms. Examination can be carried out of executive functioning as well as social and cognitive abilities but may need adaptation of standardized tests to take account of special needs.

Assessments for developmental coordination disorder typically require a developmental history, detailing ages at which significant developmental milestones, such as crawling and walking, occurred. Motor skills screening includes activities designed to indicate developmental coordination disorder, including balancing, physical sequencing, touch sensitivity, and variations on walking activities.

The American Psychiatric Association has four primary inclusive diagnostic criteria for determining if a child has developmental coordination disorder.

The criteria are as follows:

1. Motor Coordination will be greatly reduced, although the intelligence of the child is normal for the age.

2. The difficulties the child experiences with motor coordination or planning interfere with the child's daily life.

3. The difficulties with coordination are not due to any other medical condition

4. If the child does also experience comorbidities such as mental retardation; motor coordination is still disproportionally affected.

Screening tests which can be used to assess developmental coordination disorder include:-

- Movement Assessment Battery for Children (Movement-ABC – Movement-ABC 2)

- Peabody Developmental Motor Scales- Second Edition (PDMS-2)

- Bruininks-Oseretsky Test of Motor Proficiency (BOTMP-BOT-2)

- Motoriktest für vier- bis sechsjährige Kinder (MOT 4-6)

- Körperkoordinationtest für Kinder (KTK)

- Test of Gross Motor Development, Second Edition (TGMD-2)

- Maastrichtse Motoriek Test (MMT)

- Wechsler Adult Intelligence Scale (WAIS-IV)

- Wechsler Individual Achievement Test (WAIT-II)

- Test of Word Reading Efficiency (TOWRE-2)

- Developmental Coordination Disorder Questionnaire (DCD-Q)

- Children's Self-Perceptions of Adequacy in, and Predilection for Physical Activity (CSAPPA)

Currently there is no single gold standard assessment test.

A baseline motor assessment establishes the starting point for developmental intervention programs. Comparing children to normal rates of development may help to establish areas of significant difficulty.

However, research in the "British Journal of Special Education" has shown that knowledge is severely limited in many who should be trained to recognise and respond to various difficulties, including developmental coordination disorder, dyslexia and deficits in attention, motor control and perception (DAMP). The earlier that difficulties are noted and timely assessments occur, the quicker intervention can begin. A teacher or GP could miss a diagnosis if they are only applying a cursory knowledge.

"Teachers will not be able to recognise or accommodate the child with learning difficulties in class if their knowledge is limited. Similarly GPs will find it difficult to detect and appropriately refer children with learning difficulties."

There is no cure for DVD/CAS, but with appropriate, intensive intervention, people with the disorder can improve significantly.

DVD/CAS requires various forms of therapy which varies with the individual needs of the patient. Typically, treatment involves one-on-one therapy with a speech language pathologist (SLP). In children with DVD/CAS, consistency is a key element in treatment. Consistency in the form of communication, as well as the development and use of oral communication are extremely important in aiding a child's speech learning process.

Many therapy approaches are not supported by thorough evidence; however, the aspects of treatment that do seem to be agreed upon are the following:

- Treatment needs to be intense and highly individualized, with about 3-5 therapy sessions each week

- A maximum of 30 minutes per session is best for young children

- Principles of motor learning theory and intense speech-motor practice seem to be the most effective

- Non-speech oral motor therapy is not necessary or sufficient

- A multi-sensory approach to therapy may be beneficial: using sign language, pictures, tactile cues, visual prompts, and Augmentative and Alternative Communication (AAC) can be helpful.

Although these aspects of treatment are supported by much clinical documentation, they lack evidence from systematic research studies. In ASHA's position statement on DVD/CAS, ASHA states there is a critical need for collaborative, interdisciplinary, and programmatic research on the neural substrates, behavioral correlates, and treatment options for DVD/CAS.

According to the DSM-IV-TR, communication disorders are usually first diagnosed in childhood or adolescence though they are not limited as childhood disorders and may persist into adulthood. They may also occur with other disorders.

Diagnosis involves testing and evaluation during which it is determined if the scores/performance are "substantially below" developmental expectations and if they "significantly" interfere with academic achievement, social interactions and daily living. This assessment may also determine if the characteristic is deviant or delayed. Therefore, it may be possible for an individual to have communication challenges but not meet the criteria of being "substantially below" criteria of the DSM IV-TR.

It should also be noted that the DSM diagnoses do not comprise a complete list of all communication disorders, for example, auditory processing disorder is not classified under the DSM or ICD-10.

The following diagnoses are included in the communication disorders:

- Expressive language disorder – Characterized by difficulty expressing oneself beyond simple sentences and a limited vocabulary. An individual understands language better than their ability to use it; they may have a lot to say but have difficulties organizing and retrieving the words to get an idea across beyond what is expected for their developmental stage.

- Mixed receptive-expressive language disorder – problems comprehending the commands of others.

- Stuttering – a speech disorder characterized by a break in fluency, where sounds, syllables or words may be repeated or prolonged.

- Phonological disorder – a speech sound disorder characterized by problems in making patterns of sound errors, i.e. "dat" for "that".

- Communication disorder NOS (not otherwise specified) – the DSM-IV diagnosis in which disorders that do not meet the specific criteria for the disorder listed above may be classified.

Developmental coordination disorder is a lifelong neurological condition that is more common in males than in females, with a ratio of approximately four males to every female. The exact proportion of people with the disorder is unknown since the disorder can be difficult to detect due to a lack of specific laboratory tests, thus making diagnosis of the condition one of elimination of all other possible causes/diseases. Approximately 5–6% of children are affected by this condition.

In 2006, the U.S. Department of Education indicated that more than 1.4 million students were served in the public schools' special education programs under the speech or language impairment category of IDEA 2004. This estimate does not include children who have speech/language problems secondary to other conditions such as deafness; this means that if all cases of speech or language impairments were included in the estimates, this category of impairment would be the largest. Another source has estimated that communication disorders—a larger category, which also includes hearing disorders—affect one of every 10 people in the United States.

ASHA has cited that 24.1% of children in school in the fall of 2003 received services for speech or language disorders—this amounts to a total of 1,460,583 children between 3 –21 years of age. Again, this estimate does not include children who have speech/language problems secondary to other conditions. Additional ASHA prevalence figures have suggested the following:

- Stuttering affects approximately 4% to 5% of children between the ages of 2 and 4.

- ASHA has indicated that in 2006:

- Almost 69% of SLPs served individuals with fluency problems.

- Almost 29% of SLPs served individuals with voice or resonance disorders.

- Approximately 61% of speech-language pathologists in schools indicated that they served individuals with SLI

- Almost 91% of SLPs in schools indicated that they servedindividuals with phonological/articulation disorder

- Estimates for language difficulty in preschool children range from 2% to 19%.

- Specific Language Impairment (SLI) is extremely common in children, and affects about 7% of the childhood population.

Learning disabilities can be categorized by either the type of information processing affected by the disability or by the specific difficulties caused by a processing deficit.

Studies have failed to find clear evidence that language delay can be prevented by training or educating health care professionals in the subject. Overall, some of the reviews show positive results regarding interventions in language delay, but are not curative. (Commentary - Early Identification of Language Delays, 2005)

Children who demonstrate deficiencies early in their speech and language development are at risk for continued speech and language issues throughout later childhood. Similarly, even if these speech and language problems have been resolved, children with early language delay are more at risk for difficulties in phonological awareness, reading, and writing throughout their lives. Children with mixed receptive-expressive language disorder are often likely to have long-term implications for language development, literacy, behavior, social development, and even mental health problems. If suspected of having a mixed receptive-expressive language disorder, treatment is available from a speech therapist or pathologist. Most treatments are short term, and rely upon accommodations made within the environment, in order to minimize interfering with work or school. Programs that involve intervention planning that link verbal short term memory with visual/non-verbal information may be helpful for these children. In addition, approaches such as parent training for language stimulation and monitoring language through the "watch and see" method are recommended. The watch-and-see technique advises children with mixed receptive-expressive language disorder who come from stable, middle-class homes without any other behavioral, medical, or hearing problems should be vigilantly monitored rather than receive intervention. It is often the case that children do not meet the eligibility criteria established through a comprehensive oral language evaluation; and as a result, are not best suited for early intervention programs and require a different approach besides the "one size fits all" model.

Sensory processing disorder since 1994 is accepted in the Diagnostic Classification of Mental Health and Developmental Disorders of Infancy and Early Childhood (DC:0-3R) and is not recognized as a mental disorder in medical manuals such as the ICD-10 or the DSM-5.

Diagnosis is primarily arrived at by the use of standardized tests, standardized questionnaires, expert observational scales, and free play observation at an occupational therapy gym. Observation of functional activities might be carried at school and home as well. Some scales that are not exclusively used in SPD evaluations are used to measure visual perception, function, neurology and motor skills.

Depending on the country, diagnosis is made by different professionals, such as occupational therapists, psychologists, learning specialists, physiotherapists and/or speech and language therapists. In some countries it is recommended to have a full psychological and neurological evaluation if symptoms are too severe.

After the initial diagnosis of speech delay, a hearing test will be administered to ensure that hearing loss or deafness is not an underlying cause of the delay. If a child has successfully completed the hearing test, the therapy or therapies used will be determined. There are many therapies available for children that have been diagnosed with a speech delay, and for every child, the treatment and therapies needed vary with the degree, severity, and cause of the delay. While speech therapy is the most common form of intervention, many children may benefit from additional help from occupational and physical therapies as well. Physical and occupational therapies can be used for a child that is suffering from speech delay due to physical malformations and children that have also been diagnosed with a developmental delay such as autism or a language processing delay. Children that have been identified with hearing loss can be taught simple sign language to build and improve their vocabulary in addition to attending speech therapy.

The parents of a delayed child are the first and most important tool in helping overcome the speech delay. The parent or caregiver of the child can provide the following activities at home, in addition to the techniques suggested by a speech therapist, to positively influence the growth of speech and vocabulary:

- Reading to the child regularly

- Use of questions and simple, clear language

- Positive reinforcement in addition to patience

For children that are suffering from physical disorder that is causing difficulty forming and pronouncing words, parents and caregivers suggest using and introducing different food textures to exercise and build jaw muscles while promoting new movements of the jaw while chewing. Another less studied technique used to combat and treat speech delay is a form of therapy using music to promote and facilitate speech and language development. It is important to understand that music therapy is in its infancy and has yet to be thoroughly studied and practiced on children suffering from speech delays and impediments.

What follows are a list of frequently used measures of speech and language skills, and the age-ranges for which they are appropriate.

- Clinical Evaluation of Language Fundamentals – Preschool (3–6 years)

- Clinical Evaluation of Language Fundamentals (6–21 years)

- MacArthur Communicative Development Inventories (0–12 months)

- The Rossetti Infant-Toddler Language Scale (0–36 months)

- Preschool Language Scale (0–6 years)

- Expressive One-word Picture Vocabulary Test (2–15 years)

- Bankson-Bernthal Phonological Process Survey Test (2–16 years)

- Goldman-Fristoe Test of Articulation 2 (2–21 years)

- Peabody Picture Vocabulary Test (2.5–40 years)

Disorders and tendencies included and excluded under the category of communication disorders may vary by source. For example, the definitions offered by the American Speech–Language–Hearing Association differ from that of the Diagnostic Statistical Manual 4th edition (DSM-IV).

Gleanson (2001) defines a communication disorder as a speech and language disorder which refers to problems in communication and in related areas such as oral motor function. The delays and disorders can range from simple sound substitution to the inability to understand or use their native language.

In general, communications disorders commonly refer to problems in speech (comprehension and/or expression) that significantly interfere with an individual’s achievement and/or quality of life. Knowing the operational definition of the agency performing an assessment or giving a diagnosis may help.

Persons who speak more than one language or are considered to have an accent in their location of residence do not have speech disorders if they are speaking in a manner consistent with their home environment or a blending of their home and foreign environment.

For nonverbal grade school children and adolescents with autism, communication systems and interventions have been implemented to enhance language and communication outcomes. Speech-generated devices, such as iPads, use visual displays for children who lack verbal language, giving them the task of selecting icons indicating a request or need. For adolescents with nonverbal autism, interventions can condition them to learn more advanced operations on speech-generated devices that require more steps (i.e. turning on device, scrolling through pages), which would allow them to enhance their communicative abilities independently.

The Picture Exchange System (PECS) is an alternative form of spontaneous communication for children with autism in which an individual selects a picture indicating a request. PECS can be utilized in educational settings and at the child’s home. Longitudinal studies suggest PECS can have long-term positive outcomes for school-aged children with nonverbal autism, specifically their social-communicative skills, such as higher frequencies of joint attention and initiation, and duration of cooperative play, which are all important roles in improving language outcomes.

It has also been suggested that a significant stage in acquiring verbal language is learning how to identify and reproduce syllables of words. One study found that nonverbal and minimally verbal children with autism are capable of enhancing their oral production and vocalizing written words by isolating each syllable of a word one at a time. The process of breaking down a syllable at a time and having it visually displayed and audibly available to the child can prompt him or her to imitate and create nonrandom and meaningful utterances.

Most of these studies contain small sample sizes and were pilot studies, making additional research significant to assess whether these findings can be generalized to all age groups of the same population. Furthermore, most studies on nonverbal autism speech-generated device communication were based on more basic skills, such as naming pictures and making requests for stimuli, while studies in advanced communication (i.e. asking "how are you?") is limited.

Many researchers are investigating the characteristics of apraxia of speech and the most effective treatment methods. Below are a couple of the recent findings:

Sound Production Treatment:

Articulatory-kinematic treatments have the strongest evidence of their use in treating Acquired Apraxia of Speech. These treatments use the facilitation of movement, positioning, timing, and articulators to improve speech production. Sound Production Treatment (SPT) is an articulatory-kinematic treatment that has received more research than many other methods. It combines modeling, repetition, minimal pair contrast, integral stimulation, articulatory placement cueing, and verbal feedback. It was developed to improve the articulation of targeted sounds in the mid-1990s. SPT shows consistent improvement of trained sounds in trained and untrained words. The best results occur with eight to ten exemplars of the targeted sound to promote generalization to untrained exemplars of trained sounds. In addition, maintenance effects are the strongest with 1–2 months post-treatment with sounds that reached high accuracy during treatment. Therefore, the termination of treatment should not be determined by performance criteria, and not by the number of sessions the client completes, in order to have the greatest long-term effects. While there are many parts of SPT that should receive further investigation, it can be expected that it will improve the production of targeted sounds for speakers with apraxia of Speech.

Repeated Practice & Rate/Rhythm Control Treatments:

Julie Wambaugh’s research focuses on clinically applicable treatments for acquired apraxia of speech. She recently published an article examining the effects of repeated practice and rate/rhythm control on sound production accuracy. Wambaugh and colleagues studied the effects of such treatment for 10 individuals with acquired apraxia of speech. The results indicate that repeated practice treatment results in significant improvements in articulation for most clients. In addition, rate/rhythm control helped some clients, but not others. Thus, incorporating repeated practice treatment into therapy would likely help individuals with AOS.

In a typical 2-year-old child, about 50% of speech may be intelligible. A 4-year-old child's speech should be intelligible overall, and a 7-year-old should be able to clearly produce most words consistent with community norms for their age. Misarticulation of certain difficult sounds ("l", "r",

"s", "z", "th", "ch", "dzh", and "zh") may be normal up to 8 years. Children with speech sound disorder have pronunciation difficulties inappropriate for their age, and the difficulties are not caused by hearing problems, congenital deformities, motor disorders or selective mutism.

The DSM-5 diagnostic criteria are as follows:

- A. Persistent difficulty with speech sound production that interferes with speech intelligibility or prevents verbal communication of messages.

- B. The disturbance causes limitations in effective communication that interfere with social participation, academic achievement, or occupational performance, individually or in any combination.

- C. Onset of symptoms is in the early developmental period.

- D. The difficulties are not attributable to congenital or acquired conditions, such as cerebral palsy, cleft palate, deafness or hearing loss, traumatic brain injury, or other medical or neurological conditions.

For most children, the disorder is not lifelong and speech difficulties improve with time and speech-language treatment. Prognosis is poorer for children who also have a language disorder, as that may be indicative of a learning disorder.