Changing terminology and diagnostic criteria: evidence based decisions and practice Dr Susan Ebbels Prof Courtenay Norbury @SusanEbbels @lilacCourt #DevLangDis #workshop

Overview of session Impetus for change Summary of CATALISE process and key changes to terminology and diagnostic criteria Summary of evidence supporting these changes Food for thought

the taxi driver test…. Language disorder Language delay Speech language and communication need Language learning impairment Language processing difficulties Specific language impairment Primary language impairment High-level language difficulty

Labels matter!! relative to prevalence and severity, ‘specific’ language impairments: attract less research interest (as measured by publications) attract less research funding attract less media attention are not recognised by the public lack of consistency in terminology contributing factor people don’t recognise we’re talking about the same thing people don’t realise its an important problem if it doesn’t have a name parents need and value labels Bishop, D.V.M. (2010) PLoS One

Included multidisciplinary input from English speaking countries SLTs, psychologists, charities, parents, teachers, etc

Key changes to terminology and criteria

Unfamiliar with local language? Competent in another language? [4] Yes START Child presents with difficulty producing or understanding language that affects everyday functioning Unfamiliar with local language? Competent in another language? [4] Yes No No Yes Features suggestive of poor prognosis? [3] No Yes Language disorder [2]

Fail to combine words at 24m Comprehension problems START Child presents with difficulty producing or understanding language that affects everyday functioning Under 3: Prediction from late language emergence to subsequent language disorder at school age is surprisingly weak. Indicators are: Fail to combine words at 24m Comprehension problems Don’t communicate via gesture Don’t imitate body movements Poor social responsiveness and joint attention Family history of language or literacy problems Unfamiliar with local language? Competent in another language? [4] Yes No No Yes Features suggestive of poor prognosis? [3] No Yes Language disorder [2]

START Child presents with difficulty producing or understanding language that affects everyday functioning 3-4 years: Prediction improves as children grow older. In 4 year olds, greater number of areas impaired, higher the likelihood that problems will persist. Sentence repetition is a relatively good marker for predicting outcomes (those with problems only with expressive phonology have generally good prognosis) Unfamiliar with local language? Competent in another language? [4] Yes No No Yes Features suggestive of poor prognosis? [3] No Yes Language disorder [2]

Prognosis particularly poor when: Receptive language is impaired START Child presents with difficulty producing or understanding language that affects everyday functioning 5 years and over: Language problems that are still evidence by 5 years are likely to persist Prognosis particularly poor when: Receptive language is impaired Non-verbal ability is relatively low Unfamiliar with local language? Competent in another language? [4] Yes No No Yes Features suggestive of poor prognosis? [3] No Yes Language disorder [2]

Associated biomedical conditions (examples) brain injury, START Child presents with difficulty producing or understanding language that affects everyday functioning Unfamiliar with local language? Competent in another language? [4] Yes Associated biomedical conditions (examples) brain injury, acquired epileptic aphasia in childhood, certain neurodegenerative conditions, genetic conditions such as Down syndrome, cerebral palsy sensori-neural hearing loss. autism spectrum disorder (ASD) intellectual disability No No Yes Features suggestive of poor prognosis? [3] No Yes Language disorder [2] Associated biomedical condition, X? Yes Language disorder associated with X [6] No Developmental Language Disorder [7]

Developmental Language Disorder No differentiating conditions START Child presents with difficulty producing or understanding language that affects everyday functioning Developmental Language Disorder No differentiating conditions “developmental” means “emerges in the course of development” Does not mean child might ‘grow out of’ problem Does not mean child unable to develop language Could drop “developmental” term for adults Large discrepancy between verbal and non-verbal ability not required Children with low non-verbal IQ (who do not meet criteria for intellectual disability) can be included as cases of DLD Unfamiliar with local language? Competent in another language? [4] Yes No No Yes Features suggestive of poor prognosis? [3] No Yes Language disorder [2] Associated biomedical condition, X? Yes Language disorder associated with X [6] No Developmental Language Disorder [7]

Additional Information START Child presents with difficulty producing or understanding language that affects everyday functioning Unfamiliar with local language? Competent in another language? [4] Yes No No Yes Features suggestive of poor prognosis? [3] No Yes Co-occurring disorders Attention (e.g., ADHD) Motor (e.g., dyspraxia, dysarthria) Literacy Speech Adaptive behaviour Behaviour/emotional problems Auditory processing (e.g., APD) Language disorder [2] Associated biomedical condition, X? Yes Language disorder associated with X [6] No Developmental Language Disorder [7] Additional Information Co-occurring disorders [9] Risk factors [10] Areas of language impairment [11]

Additional Information START Child presents with difficulty producing or understanding language that affects everyday functioning Unfamiliar with local language? Competent in another language? [4] Yes No No Yes Features suggestive of poor prognosis? [3] No Yes Language disorder [2] Associated risk factors Family history Male Younger sibling in large family poverty Fewer years of parental education Associated biomedical condition, X? Yes Language disorder associated with X [6] No Developmental Language Disorder [7] Additional Information Co-occurring disorders [9] Risk factors [10] Areas of language impairment [11]

Additional Information START Child presents with difficulty producing or understanding language that affects everyday functioning Unfamiliar with local language? Competent in another language? [4] Yes No No Yes Features suggestive of poor prognosis? [3] No Yes Language disorder [2] Areas of language impairment Phonology (may get dual diagnosis of DLD with SSD) Morphology Syntax Word finding and semantics Pragmatics/language use Discourse Verbal learning and memory Associated biomedical condition, X? Yes Language disorder associated with X [6] No Developmental Language Disorder [7] Additional Information Co-occurring disorders [9] Risk factors [10] Areas of language impairment [11]

Summary of terminology (as used by SLTs) Children with a previous diagnosis of SLI would all meet new criteria for DLD Children with previous diagnosis of SLI are a subset of those who meet new criteria for DLD DLD is broader than SLI as non-verbal criteria relaxed (although those with intellectual disability would not be included) Children with DLD are a subset of those with Language Disorder (those who do not have differentiating conditions) Children with LD are a subset of those with SLCN

Advantages of new terminology Agreed by consensus If all SLTs use same criteria, should reduce disputes between SLTs (e.g. between independent vs NHS practitioners) Can use different levels of labels depending on purpose: SLCN for discussing with policy makers (all children who may require SLT support) Language Disorder for discussing with commissioners/teachers (all children likely to need SLT support including a focus on language) DLD for highlighting particular needs of and support required by this group which may differ from others (e.g., ASD) Full description of areas of language impairment and co-occurring/associated disorders – for planning intervention and educational provision for an individual child Used in DSM-V Likely to be used in ICD-11

Terminology vs Intervention In an ideal world, intervention and educational provision should be based on a detailed understanding of the child’s full profile of strengths and needs In this case, changes in terminology / criteria should have no effect on intervention/educational provision, as the children’s needs have not changed

Terminology versus Intervention However, in some places, intervention/educational provision has been determined by diagnosis (using exclusionary criteria) some children have been excluded from services despite having needs which could benefit, changes in criteria and labels could mean more children are now eligible for services, creating greater pressures But the need always was and is still there…

Problems with new terminology We have a big problem when talking with education services Education uses terminology in a different way – especially SLCN

Terminology as used by education

Problems with new terminology We have a big problem when talking with education services Education uses terminology in a different way – especially SLCN Primary SLCN most similar to DLD Secondary SLCN most similar to “Language Disorder associated with X” But SLTs use SLCN to mean all children who we may need to be involved with for any reason

Evidence based decisions

why ‘specific’ language impairment? previously “developmental dys/aphasia” term ‘SLI’ took hold in era of universal grammar Language is modular / innate Can be selectively impaired non-verbal cognitive abilities limit language development Language impairment ‘in line’ with mental age is different to LI when discrepancy Children with low non-verbal ability don’t learn as fast or respond to therapy

view that language is ‘selectively’ impaired is under pressure… Behavioural moderate correlations between language and non-verbal ability children with intellectual disabilities (i.e. Down syndrome) benefit from language intervention (Burgoyne et al. 2015) ‘selective’ impairments derived from arbitrary cut-offs on continuous data

could improving language drive other kinds of learning? Reilly et al. (2014) IJLCD

what is the causal relationship of language and non-verbal ability? language is a fantastic problem solving tool!!

view that language is ‘selectively’ impaired is under pressure… Neurobiological genetic evidence is that ‘specific’ and ‘non-specific’ language impairment arise from same genetic mechanisms developing brain is not as rigidly modular as adult brain – language processing is distributed (Krishnan, Watkins, Bishop, 2016, for recent review) neural circuits implicated in language disorder involve general, complex rule-governed LEARNING ‘specific’ deficits highly unlikely in a developing system

Impact of changing criteria on prevalence and clinical presentation

If child has language difficulties at school entry, what co-morbidities are present from the start? How do co-morbidities affect language change over time?

Prevalence Year 1 % of population Developmental Language Disorder (cause unknown) 7.58% higher NVIQ 4.80% lower NVIQ 2.78% Language Disorder (known cause and/or intellectual impairment) 2.34% Total Language Disorder 9.92%

children with lower non-verbal cognitive ability (70 – 85) do NOT have a different clinical profile Low NVIQ (>-2SD & <-1SD) Normal NVIQ (>= -1SD) T-test N 156 256 IDACI rank 17987.59 17770.62 ns Age (months) 69.91 72.81 Communication checklist 19.61 18.06 Social, emotional, behavioural problems 7.00 7.81 Academic attainment 27.20 28.32 Weighted group comparisons using linearised SEs

children with lower non-verbal cognitive ability (70 – 85) do NOT have a different profile of language deficit

SLT COULD BE CRUCIAL TO QUALITY OF LIFE FOR THESE CHILDREN! NOTE: children with Language Disorder and associated conditions (ASD, Down syndrome, etc): more severe language deficits more severe social, emotional, behavioural problems greater academic challenges more likely to be in specialist education provisions SLT COULD BE CRUCIAL TO QUALITY OF LIFE FOR THESE CHILDREN!

why developmental language “disorder”? ‘disorder’ indicates a problem that should be taken seriously. puts language disorder on a par with other neurodevelopmental disorders autism spectrum disorder developmental co-ordination disorder attention deficit hyperactivity disorder is compatible with the two main diagnostic systems, DSM-5 and ICD11 term ‘specific’ language impairment has connotations that are misleading and confusing

DLD is a lifelong disorder

language is incredibly stable Better than Year 1 Total Language Year 3 (z-score) Worse than Year 1 Total Language Year 1 (z-score) ICC = .93

stable, but considerable language ‘growth’ over time Not only is this group improving, growth RATE is similar to TD peers

to “narrow the gap”… LD groups must learn language at a faster rate than the TD group Is this possible? Is there a critical period? Is current provision sufficient to do it?

food for thought… More inclusive criteria: Interface with education: How to manage the need… Interface with education: Joint working paramount Lifelong disorder: Changing need and limited adult services at present Consider the goal of intervention What is a ‘good’ outcome?

Key papers to read Bishop, D. V. M., Snowling, M. J., Thompson, P. A., Greenhalgh, T., & 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. http://onlinelibrary.wiley.com/doi/10.1111/jcpp.12721/full Bishop, D. V. M., Snowling, M. J., Thompson, P. A., Greenhalgh, T., & The CATALISE Consortium. (2016). CATALISE: a multinational and multidisciplinary Delphi consensus study. Identifying language impairments in children. PLOS One, 11(7), http://dx.doi.org/10.1371/journal.pone.0158753 Ebbels SH, McCartney E, Slonims V, Dockrell JE, Norbury C. (2017) Evidence based pathways to intervention for children with language disorders. PeerJ Preprints 5:e2951v1, https://doi.org/10.7287/peerj.preprints.2951v1 Norbury, C. F., Gooch, D., Wray, C., Baird, G., Charman, T., Simonoff, E., . . . Pickles, A. (2016). The impact of nonverbal ability on prevalence and clinical presentation of language disorder: evidence from a population study. Journal of Child Psychology and Psychiatry, http://dx.doi.org/10.1111/jcpp.12573