The information on this page has been developed in response to questions asked at our DLD webinar on 4 November 2020.

To make the responses manageable, we have presented several general questions which encompass the themes coming out of questions on the day. Where possible, responses will direct you to answers within the CATALISE studies or webinar materials themselves. Written information from the presenters has been collated by RCSLT, along with information from additional sources.

RCSLT and the presenters are not able to comment on specific clinical cases, but if you feel your own question has not been covered, please get in touch.

1. What resources are available to assist SLTs in diagnosing and supporting children with language disorder/developmental language disorder (DLD)?

CATALISE resources

The two studies conducted by the CATALISE consortium are both free to access online:

RCSLT resources

  • Briefing paper (PDF) published in 2017, updated in 2020, to support therapists with the changes to terminology and criteria.
  • RCSLT members have access to the DLD guidance pages, including learning tools and evidence resources.
  • On the webinar page there are videos of the presentations, slides, written case studies and the previous webinar ‘DLD – What do the changes mean for service delivery?’
  • Download a set of slides (PDF) that specialists can use to talk about the changes with their teams.

Other resources

  • The DLD Toolbox includes useful discussion and flowcharts to help with differential diagnosis.
  • The DLD Project provides evidence-based information for therapists, families and educators, including via the Talking DLD Podcast.
  • NAPLIC provide a range of resources and are in the process of developing an online learning package for professionals about DLD.
  • The RADLD, DLD and Me and Afasic websites provide support for children, families and professionals.
  • Moor House Research and Training Institute also has information and training videos for parents and teachers, with more for SLTs coming soon.

2. What is the appropriate diagnosis for a child who has features of language disorder, in combination with phonological difficulties or speech sound disorder?

A diagnosis of DLD can be accompanied by specification of the affected domains, which include phonology (see webinar slides PDF for a diagram). However, poor phonological awareness is not sufficient for a diagnosis, as impairments in other language skills are required.

“Where the child has a mixture of language disorder and motor or structural problems with speech production, a dual diagnosis of DLD with SSD [speech sound disorder] is appropriate.” (Statement 11, Bishop et al, 2017)

It is important to remember that SSD is an “…umbrella heading either speech sound disorder…or speech sound disorders… abbreviated SSD either way” (Bowen, 2015: 4). Depending on the categorisation model employed, clinicians should then go on to transcribe and analyse the child’s speech and reach a definitive diagnosis or diagnoses.

For example, Dodd’s classification (2004) includes phonological delay, consistent phonological disorder, inconsistent phonological disorder, articulation disorder, or motor speech disorders such as dysarthria and dyspraxia. Helpful resources include the Child Speech Disorder Research Network website and the Ask the Experts (PDF) feature published in Bulletin (August 2019).

A learning space for SLTs supporting young children with co-occurring features of SSD and DLD launched in January 2021.

3. Can children with learning disability, learning difficulties, global developmental delay or low non-verbal IQ be diagnosed with DLD?

Susan Ebbels discussed this issue in her presentation (see particularly from slide 22/13:19) and this question was touched on in the live Q and A at the end of the webinar. Susan has also written a clarification of the RCSLT briefing paper for Bulletin.

Intellectual disability is a differentiating condition and would typically entail non-verbal IQ level below 70, as well as major limitation of adaptive behaviour. Intellectual disability is used in DSM-V and is used extensively in the US. ‘Learning disability’ tends to be the term used in the UK.

Where a child with language disorder has been diagnosed with a learning disability, the diagnosis would be ‘language disorder associated with intellectual disability/learning disability’.

Learning difficulties is a more general term, which might be used in education, for example for a child with dyslexia, and does not necessarily indicate a differentiating biomedical condition. Global developmental delay tends to be used for younger children who have not reached milestones in two or more developmental areas.

It is not a diagnosis/biomedical condition, although it might be followed up by a diagnosis of intellectual disability or other biomedical condition. See question 4 for more discussion of cases where information is unclear or still emerging.

“A child with a language disorder may have a low level of nonverbal ability. This does not preclude a diagnosis of DLD… It is important to recognise that language can be selectively impaired in a child with normal nonverbal ability, but this statement confirms that a large discrepancy between nonverbal and verbal ability is not required for a diagnosis of DLD. In practice, this means that children with low nonverbal ability who do not meet criteria for intellectual disability (Harris, 2013) can be included as cases of DLD.” (Statement 8, Bishop et al, 2017)

4. What if I need more information to determine whether a child with language difficulties has an intellectual disability or autistic spectrum disorder (ASD)?

As discussed in Susan Ebbels’ presentation, diagnosis of differentiating conditions is likely to need a multidisciplinary team. It is not the SLT’s role to formally assess cognitive skills or to diagnose intellectual/learning disability.

Where a child is undergoing wider assessment and seems likely to receive a diagnosis for another biomedical condition, a therapist may wish to use DLD provisionally or use ‘language disorder’ as an umbrella term, which can be revised to be more specific once there is more information.

However, the CATALISE studies are clear that therapists can be confident in giving a diagnosis of DLD, unless there is a known biomedical aetiology. If a differentiating condition is diagnosed later, then the diagnosis can be changed to ‘language disorder associated with…’.

In all of these cases, SLTs can emphasise the degree of difficulty with language and how that might be a priority for intervention. The focus should be on the functional impact of difficulties and the needs of the child, as final diagnosis should not impact on provision.

“SLTs have an important role to play with children whose language disorder occurs with a biomedical condition. Language disorders occurring with these conditions need to be assessed and children offered appropriate intervention.” (RCSLT Briefing Paper, 2017)

5. Can I diagnose DLD where a child has a diagnosis of condition not specified by CATALISE as a differentiating biomedical condition, such as dyslexia, ADHD or auditory processing disorder?


“Co‐occurring disorders are impairments in cognitive, sensori‐motor or behavioural domains that can co‐occur with DLD and may affect pattern of impairment and response to intervention, but whose causal relation to language problems is unclear. These include attentional problems (ADHD), motor problems (developmental coordination disorder or DCD), reading and spelling problems (developmental dyslexia), speech problems, limitations of adaptive behaviour and/or behavioural, and emotional disorders.” (Statement 9, Bishop et al, 2017)

“The terminology used for neurodevelopmental disorders can create the impression that there is a set of distinct conditions, but the reality is that many children have a mixture of problems. Indeed, the same problems may be labelled differently depending on the professional the child sees. For example, the same child may be regarded as having DLD by a SLT/P, dyslexia by a teacher, auditory processing disorder by an audiologist, or ADHD by a paediatrician. Given our focus on DLD, our aim with this statement was to make it clear that presence of another neurodevelopmental diagnosis does not preclude DLD.” (Statement 9, Bishop et al, 2017)

“There was discussion about including auditory processing disorder (APD) as a co‐occurring condition. This category is controversial (Moore, 2006), but this should not lead to it being ignored. Children who are given this diagnosis often have co‐occurring language problems which require expert evaluation (Dawes and Bishop, 2009; Sharma, Purdy, and Kelly, 2009).” (Statement 9, Bishop et al, 2017)

Co-occurring disorders are particularly important for planning intervention. Depending on who you are reporting the diagnosis to, it may be more or less important to specify these.

6. Can I diagnose DLD where there are other developmental factors, eg trauma, effects of drugs/medication in utero?

Yes, unless there is also a differentiating condition.

“Risk factors are biological or environmental factors that are statistically associated with language disorder, but whose causal relationship to the language problem is unclear or partial. Risk factors do not exclude a diagnosis of DLD.” (Statement 10, Bishop et al, 2017).

Risk factors are likely to be less important than co-occurring disorders at an individual level for predicting response to intervention. They need to be borne in mind when planning intervention, but would not usually be specified as part of a diagnosis.

7. Are there any standardised assessments or procedures that are recommended or should be included when diagnosing language disorder? What if there isn’t time for a full battery of language assessments?

To provide intervention, a full picture of the child’s needs is required, so it is good practice to get lots of this information prior to diagnosis, if possible. However, clinical markers (see below) may be useful as an indicator of whether more detailed assessment is required.

“Multiple sources of information should be combined in assessment, including interview/questionnaires with parents or caregivers, direct observation of the child, and standardized age-normed tests or criterion-based assessments.” (Bishop et al, 2016)

“The main challenge facing those attempting to use the concept of language disorder that we advocate is that there are few valid assessments of functional language and relatively limited evidence regarding prognostic indicators.” (Bishop et al, 2017)

Do what formal and functional assessment you can, state what you can conclude from what you have done and if you need more time, you need to either create or argue for this, or state that due to limited time for assessment you are not able to make a diagnosis. It may be harder to make a decision where difficulties are less severe.

In instances where formal assessment is not possible, for example due to emotional or behavioural difficulties, a diagnosis can still be made, especially if you do a language sample analysis.

Ideally, assessment would include classroom observation, but where this is not possible SLTs should at least discuss functioning with school staff and parents.

8. Are there any specific assessment scores that are used in making a diagnosis of DLD?

The CATALISE panel “cautions against defining language disorder solely in terms of statistical cut‐offs on language tests.” (Bishop et al, 2017).

Different tests have different cut-off points giving the best level of sensitivity and specificity (depends on several factors, including the standardisation sample). Thus, having a single cut-point to be used for all tests, is not to be recommended.

“There is no clear cut-off that distinguishes between language impairment (regardless of its cause) from the lower end of normal variation of language ability … Regardless of the cause, where a person’s language abilities fall at the low end of the normal range, it can be appropriate to recommend intervention, ranging from environmental adjustments to specialised help, depending on the severity and nature of the problems and accompanying risk factors. However, it should be noted that many children who are judged clinically to have language impairments score within one SD of the mean on many commonly used language tests. This suggests that many instruments used to assess child language are insensitive to impairments that affect day-to-day language functioning, possibly because items can be answered using nonlinguistic compensatory strategies.” (Statement 12, Bishop et al, 2016)

9. Are clinical markers useful in making a diagnosis?

Clinical markers can be useful as a screen, in the context of a full picture of the child’s needs. (Statement 16, Bishop et al, 2016).

Sentence repetition (difficulty repeating back sentences accurately) has been identified as a particularly good marker for language disorder. Impairments in syntax and use of tenses are also strong indicators and most tests include focus on these skills.

10. What about the impact of other skills like working memory?

Working memory and language difficulties can co-occur and interact. A child who has difficulties with both language and working memory is likely to be particularly disadvantaged. However, the current evidence indicates that working on language is more effective than working on memory.

11. If a child has pragmatic difficulties but no other language difficulties (syntax and semantics fine) and does not have ASD, should we then diagnose DLD?

Yes, but you need to be specific as to the nature of their DLD.

“Pragmatic difficulties … are hallmarks of the communicative problems seen in ASD, but are also found in children who do not meet criteria for autism.

Specific terminology has been proposed for nonautistic children with pragmatic impairments. In ICD‐11, the term pragmatic language impairment is used as a descriptive qualifier within DLD. In DSM‐5, a new category of social (pragmatic) communication disorder (SPCD) has been introduced – see Baird and Norbury (2016).

We considered adopting the DSM‐5 term in CATALISE, but decided against this for several reasons. First, in DSM‐5, SPCD is seen as a new category of neurodevelopmental disorder, whereas we regard pragmatics as part of language, and hence pragmatic impairment as a type of language disorder. Second, the label SPCD emphasises social communication, rather than language; in contrast, our focus is on linguistic problems.

Interventions are being developed that address linguistic as well as social aspects of such communication problems (Adams, 2008), and a focus on pragmatic language as a feature of DLD should help direct children to appropriate intervention.” (Statement 11, Bishop et al, 2017)

12. Do pragmatic/social communication difficulties come under the remit of speech and language therapists?


“Training of speech and language therapists/pathologists should encompass assessment and planning of intervention for children who have pragmatic difficulties (including those diagnosed with DSM-5 social communication disorder). Other professional groups, including educators and psychologists, may also play a major role in identifying and planning for the needs of these children.” (Statement 19, Bishop et al 2016)

13. Are ASD and DLD seen as being on a continuum?

For many years autism was regarded as quite distinct from other developmental language difficulties, and diagnosis of ASD would lead to a different educational/intervention pathway. However, it is now recognised that the distinction between ASD and other conditions is not as clearly delineated as some textbooks might suggest.

“On the one hand, there are children with social communication disorder/pragmatic language impairment, who have pragmatic impairments without all the features necessary for a diagnosis of ASD (see item 19).

“On the other hand, a high proportion of verbal children with ASD have language difficulties similar to those seen in non-autistic children, especially with grammar or phonology, though there is debate as to whether the similarities are merely superficial. Where structural language impairment co-occurs with ASD there are more severe problems with receptive language and functional communication.

“There is as yet no research evidence on whether intervention approaches used with language-impaired children are effective for analogous difficulties in ASD.” (Statement 24, Bishop et al 2017)

14. What is best practice when working with families who have complex language backgrounds?

Examples of working with bilingual children often describe a consistent home language context. However, some families have more complex language backgrounds, with several languages spoken in the home and parents using English with their children, providing a poor language model, due to incomplete competency in this language. These children may take longer to acquire English, and therefore a differential diagnosis is more complicated. What is best practice in these cases?

The webinar prompted a useful discussion about diagnosing DLD in a bilingual child. See the additional presentation by Sean Pert about DLD in the bilingual context and relevant case studies.

RCSLT bilingualism guidance is clear that assessment in all languages the child speaks is essential to ensure a true picture of their skills. This also provides a unique opportunity for the therapist to encourage use of the home language and promote bilingualism.

It is very important to discuss with the parents that the acquisition of language requires a good model (constructivist language acquisition, see Ambridge and Lieven (2011) and Ambridge et al (2006)). The best model is the parent’s home language, and they should be encouraged to use this language with the child.

Parents often believe that using English will improve the child’s success in education, compared to acquiring home language(s). This myth needs to be addressed and parents reassured that children will acquire English (or the language of education, such as Welsh) more quickly if they have a firm foundation in their home language.

15. Is it appropriate to make a diagnosis when assessments have been conducted remotely?

This question was discussed in the live Q and A at the end of the webinar. Publishers of assessments may have specific advice about using their tests remotely, but even if this is possible, it is likely to be harder to assess children’s functioning remotely.

Depending on the situation, it may be appropriate to say that the diagnosis cannot be confirmed until more information is gained. However, if it seems likely, then it would be better to start discussing the hypothesis and allow parents and other professionals to start thinking about it.

During the COVID-19 pandemic, the changes to remote practice have been rapid, and evidence is still in the early stages. The RCSLT has updated its guidance on telehealth and produced a range of resources for members, including on the subject of remote assessment.

16. Are there specific criteria or thresholds for “a significant impact on everyday social interactions or educational progress” or the severity of disorder? What if the child’s functioning improves?

“The main challenge facing those attempting to use the concept of language disorder that we advocate is that there are few valid assessments of functional language and relatively limited evidence regarding prognostic indicators.” (Bishop et al, 2016)

It is also important to think about the child’s current environment and support already in place. It could be that they function well in this scenario, but would not in a more challenging environment. Joint setting of short and longer term goals is likely to be helpful.

17. Is limited response to intervention part of the criteria for diagnosis?

Some limited progress was referred to in the webinar case studies, as part of discussing the persisting nature of language disorder. All children are different and limited response could be due to a number of factors. It may add to the clinical picture you are building but is not imperative for diagnosis. Children with language disorder will benefit from the right interventions, but their difficulties will not completely resolve.

“The term ‘language disorder’ is proposed for children who are likely to have language problems enduring into middle childhood and beyond, with a significant impact on everyday social interactions or educational progress… This statement clarifies that prognosis should be a key factor in the definition of language disorder; that is, the term should include those with language problems that lead to significant functional impairments unlikely to resolve without specialist help. There is no sharp dividing line between language disorder and typical development, but we can use relevant information from longitudinal studies to help determine prognosis.” (Statement 2, Bishop et al, 2017)

It is the case that some language difficulties (especially in younger children) will resolve with general intervention, and this is one of the reasons for caution in giving a diagnosis to younger children.

Courtenay Norbury gave a LuCiD Seminar in December 2020 on the topic of Stability and Change in DLD.

18. Is it possible to give a diagnosis of DLD or ‘language disorder associated with X’? to children who are under 5 years?

Yes, if there are indicators of persisting difficulties. “Research evidence indicates that predictors of poor prognosis vary with a child’s age, but in general language problems that affect a range of skills are likely to persist.” (Statement 3, Bishop et al, 2017)

See Susan Ebbels’ presentation (see particularly from slide 6/2:10) and the live Q and A at the end of the webinar. See also Susan’s clarification of the RCSLT briefing paper (PDF), which appeared in Bulletin.

See also Statements 4-8 Bishop et al (2016).

19. Diagnosis is challenging for older children, especially when they have had long absences from school, which could affect their language scores. It can be difficult to get information about their language when they were younger, before school absences. Case history can also be challenging for looked-after children. What would you advise in these cases?

Therapists can only draw conclusions from the data available. Assess what you can, do as through a case history as possible (from multiple sources) and use your clinical judgement to decide whether a diagnosis is appropriate, stating clearly if there is any uncertainty and why.

Some aspects of language are more likely to be affected by (lack of) school than others. Vocabulary is likely to be very affected, but grammar much less so. So, grammatical difficulties at secondary age, may be more likely to indicate DLD.

20. Should traditional language units that previously focused on children with specific language impairment (SLI) now focus on children with DLD and ‘language disorder associated with X’?

SLI should be removed from usage in such provisions. There will be local policy decisions around the focus of such units and the related terminology. A language unit could be appropriate for some children with associated conditions, but not for all: placement should depend on needs not diagnosis.

21. How can you record your findings and any working diagnosis for others, within time constraints?

Reports and case notes are valuable tools to share information about identified priorities and concerns, assessment, functional skills, therapy goals, strategies and how SLT and therapy partners can work to address these. They can be kept as concise as possible.

There will be times when you are uncertain, and it is perfectly acceptable to document evolving clinical hypotheses in case notes and even reports if necessary.

It is important that families are involved in discussions around diagnosis and goals and that reports are accessible to them.

22. What is recommended for assessment and diagnosis in adults?

The current evidence base in this area is very limited and has been recognised as a priority for research by CATALISE (Bishop et al, 2016) and in the RCSLT Research Priority Setting Partnership. Fidler, Plante and Vance (2011) have explored identification in adults and their paper has led some members to explore use of the Modified Token Test (Morice and McNicol, 1985) with adults in DLD diagnosis. Barry, Yeasin and Bishop’s paper (2007) will also be of interest to members in this field.

The principles relating to assessment and diagnosis in children will still be applicable. You will also be able to evaluate the evidence relating to children, and draw from this, where appropriate, in conjunction with your clinical expertise and the perspective of your client, as per the EBP model.

The second CATALISE paper notes: “‘developmental’ can become less useful, or even confusing, as individuals grow older. One proposed solution was to drop the ‘developmental’ part of the term in adulthood – this is how this issue is typically handled in the case of (developmental) dyslexia, where affected adults usually refer to themselves as ‘dyslexic’.” (Bishop et al, 2017)

People you are working with may want to consider signing up to the Engage with Developmental Language Disorder network so they can be notified of opportunities to participate in research.

We also have a case study of an adult diagnosis (PDF).


Remember that many journal articles are open access or can be accessed for free by members via our journal collection.

Adams, C (2008) Intervention for children with pragmatic language impairments: Frameworks, evidence and diversity. In CF Norbury, JB Tomblin and DVM Bishop (Eds), Understanding developmental language disorders. Hove, UK: Psychology Press.

Ambridge, B, and Lieven, EVM (2011) Child language acquisition: contrasting theoretical approaches. Cambridge: Cambridge University Press.

Ambridge, B, Theakston, AL, Lieven, EV and Tomasello, M (2006) The distributed learning effect for children’s acquisition of an abstract syntactic constructionCognitive Development. 21(2): 174-193.

Baird, G, and Norbury, CF (2016) Social (pragmatic) communication disorders and autism spectrum disorder. Archives of Disease in Childhood. 101: 745-751.

Barry, Johanna and Yasin, I and Bishop, Dorothy (2007) Heritable risk factors associated with language impairments. Genes, brain, and behavior. 6: 66-76.

Bishop, DVM., Snowling, MJ, Thompson, PA, Greenhalgh, T, and The CATALISE Consortium (2016) CATALISE: a multinational and multidisciplinary Delphi consensus study. Identifying language impairments in children. PLOS One, 11(7), e0158753.

Bishop, DVM, Snowling, MJ, Thompson, PA, Greenhalgh, T, and The CATALISE Consortium (2017) Phase 2 of CATALISE: a multinational and multidisciplinary Delphi consensus study of problems with language development: Terminology. Journal of Child Psychology and Psychiatry. 58 (10), 1068- 1080.

Bowen, C (2015) Children’s Speech Sound Disorders. Chichester, UK: Wiley Blackwell.

Broomfield, J, and Dodd, B (2004) The Nature of Referred Subtypes of Primary Speech Disability. Child Language Teaching and Therapy. 20(2): 135-151.

Dawes, P, and Bishop, D (2009) Auditory processing disorder in relation to developmental disorders of language, communication and attention: A review and critique. International Journal of Language and Communication Disorders. 44: 440-465.

Fidler, L, Plante, E and Vance, R (2011) Identification of Adults With Developmental Language Impairments. American journal of speech-language pathology /American Speech-Language-Hearing Association. 20:2-13.

Moore, DR (2006) Auditory processing disorder (APD): Definition, diagnosis, neural basis, and intervention. Audiological Medicine. 4: 4-11.

Morice, R and McNicol, D (1986) The Comprehension and Production of Complex Syntax in Schizophrenia. Cortex; a journal devoted to the study of the nervous system and behavior. 21: 567-80.

Royal College of Speech and Language Therapists (2020) RCSLT briefing paper on Language Disorder with a specific focus on Developmental Language Disorder (PDF)

Sharma, M, Purdy, SC, and Kelly, AS (2009) Comorbidity of Auditory Processing, Language, and Reading Disorders. Journal of Speech Language and Hearing Research. 52: 706-722.

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