What is cognitive referencing and should Speech and Language Therapists (SLTs) use it?

Cognitive referencing, also known as the discrepancy model, refers to the outdated practice of determining eligibility for a diagnosis, and/or Speech and Language Therapy (SALT) services by comparing an individual’s language abilities with their non-verbal IQ. According to this, children with language difficulties would be expected to have average overall intelligence, i.e. there ought to be a large “discrepancy” between their verbal and nonverbal scores in order to qualify for SALT support.

The reason for this was that a certain level of cognition was believed necessary to make progress with language skills, and therefore to benefit from intervention. An individual’s nonverbal intelligence scores were considered the “ceiling” up to which progress could be made. In areas where services were very stretched, and where it was felt necessary to prioritise those who would benefit the most, below average IQ was sometimes used as a reason to deny services.

This practice was quite common during the 1980s and 1990s, especially in school settings, and it is still used in some circles now. The previously used label of Specific Language Impairment (SLI), also used cognitive referencing as part of its “exclusionary criteria”. Since it was meant to identify language disorders that were “specific” in nature, i.e. occurring in the absence of any other difficulties, such as hearing impairment or general cognitive deficits, those with low non-verbal IQ were automatically excluded.

However, the very notion of a “pure” language disorder is questionable, and the exception rather than the rule in clinical practice anyway. If we were to restrict support to only those who presented with “pure” language disorders, then we risk denying services to those most in need (Bishop et al, 2016). In 2016, a panel of experts rejected the label as “not reflecting clinical realities” (Bishop et al, 2016) and it has now been replaced with the more inclusive “Developmental Language Disorder” (DLD), which does not apply such restrictions.

For further discussion on terminology, please see my article: https://secondaryschoolslt.wordpress.com/2026/02/26/developmental-language-disorder-a-brief-history-of-terminology/

There are several other problems with cognitive referencing, and many experts in the field, e.g. Larson and McKinley (2003) have argued strongly against the practice over the years. For one thing, the supposedly nonverbal tests used are rarely a pure measure of nonverbal ability (Paul & Norbury, 2012). While the test items themselves use visual stimuli, some type of oral instructions are usually involved.

What’s more, children who employ verbal strategies such as inner speech may have an advantage over their peers when solving the complex problems involved in these tests. Since those with language disorders do not tend to use these kind of strategies they are likely to score lower. Ironically, the very tests used to help identify those in need of support are likely to disadvantage those most in need.

Secondly, whereas cognition was previously understood to underlie and to support language skills, the relationship between the two is now considered to be more complex and bi-directional. For a start, individuals with poor non-verbal ability, yet strong language ability do exist (Larson and McKinley, 2003). This finding alone appears to disprove the theory that a certain level of cognition is needed to make progress with language skills. And individuals with poor nonverbal IQ have been found to benefit from intervention too (Paul & Norbury, 2012, p. 7).

Speaking of the interplay between verbal and nonverbal abilities, Marilyn Nippold (2014) observed in one paper how “complex talk reflects complex thought”. During one study, she found that challenging students to complete more demanding tasks or use more advanced forms of discourse pushed them to use longer, more complex sentence structures than they would otherwise. I imagine that both influence each other in a symbiotic way: if students’ understanding of a particular concept or topic is vague, and they lack the means to express themselves on it, then providing them with the words and sentence structures to do so may help to elucidate it for them.

I have personally experienced how writing, the process of putting different words together, and rearranging sentences can help to develop and refine my thinking. Thought without words or images is likely possible, but I imagine it to be a hazy, undefined sort of thing; words can give form and solidity to those ideas forming in the background.

As an optimist, I see in this an opportunity to support our students beyond what might be considered the boundaries of SLT; if we can give our students words and structures to help them think, then why wouldn’t we? Ultimately, I agree with Larson and McKinley (2003), who stress that we should be thinking of reasons to provide services to adolescents, rather than withhold them.

Notes

Bishop DVM, Snowling MJ, Thompson PA, Greenhalgh T, CATALISE consortium (2016)

CATALISE: A Multinational and Multidisciplinary Delphi Consensus Study. Identifying Language

Impairments in Children. PLoS ONE 11(7): e0158753. doi:10.1371/journal.pone.0158753

Bishop, D.V.M., Snowling, M.J., Thompson, P.A., Greenhalgh, T., and the CATALISE-2 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), pp. ​ 1068–1080. doi:10.1111/jcpp.12721​

Larson, V.L. and McKinley, N.L. (2003) Communication solutions for older students. Thinking Pub. 

Nippold, Marilyn. (2014). Language Intervention at the Middle School: Complex Talk Reflects Complex Thought. Language, Speech, and Hearing Services in Schools. 45. 153-156. 10.1044/2014_LSHSS-14-0027.

Norbury, C.F., Gooch, D., Wray, C., Baird, G., Charman, T., Simonoff, E., Vamvakas, G., & 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, 57(11), pp. 1247–1257. Available at: https://acamh.onlinelibrary.wiley.com/doi/10.1111/jcpp.12573