The American Speech and Hearing Association (2020) reported that at the year-end of 2019, only 13,211 of 201,961 individuals represented by ASHA reported meeting ASHA’s definition of a bilingual service provider. For those of us who actively avoid math, that’s only 6.5% percent of those 201,961 people with an ASHA certification. Speech language pathologists (SLPs) made up a majority (11,865) of that 13,211 figure. This statistic becomes problematic when considering the amount of cultural and linguistic diversity (CLD) that is found on the average caseload for all SLPs (Torres, Rodríguez, & Payne, 2018). Assessment and treatment considerations for CLD populations are not obvious for anyone, bilingual or not, which is why it is helpful to have training in cultural and linguistic diversity (Torres, Rodríguez, & Payne, 2018). As a graduate student in a Cultural and Linguistic Diversity Emphasis Program and Bilingual Certification Program, I discovered that I wasn’t as culturally and linguistically aware as I thought when it came to service delivery. In order to best capture the communication profile of our CLD clients, there are specific adjustments that need to be made for assessment and intervention.

One of the adjustments that SLPs can make is to increase their familiarity with characteristics of bilingualism such as code-mixing. Code-mixing refers to the use of two languages with the same sentence or part of a conversation. Code-mixed utterances may use phonological, lexical, morphosyntactic, or pragmatic patterns from one language (L1) and the other language (L2) (Genesse, 2002). Code-mixing is a natural, common, and normal act for bilingual children and adults (Genesse, 2002).  

Before we dive into code-mixing in the clinical setting, let’s review what bilingualism is and what it is not. Bilingualism is fluency in two or more languages. There is simultaneous and sequential bilingualism. Simultaneous bilingualism is the acquisition of two languages from birth or before the age of three. Sequential bilingualism is the acquisition of a second language after the age of three.

  • Bilingualism does not cause a delay in speech and language development (Junker, et al., 2002; Paradis, Nicoladis, & Genesee, 2001; Patterson, 2004).
  • Very young bilingual children may have a slightly shorter mean length of utterance (MLU), but this is only a difference, not a disorder (Paradis, Nicoladis, & Genesee, 2001).
  • Bilinguals do not have smaller or less developed vocabularies than monolinguals (Junker, et al., 2002; Paradis, Nicoladis, & Genesee, 2001; Patterson, 2004).

Considering these facts about bilingualism, we can see how better information on CLD populations can help clinicians know the right questions to ask. Questions about language acquisition and language exposure are instrumental in designing assessment to detect a difference versus a disorder (Ortiz, 2019). This is also where code-mixing comes into play. It’s important to know that code-mixing has several functions such as filling in a gap in language, pragmatic reasons, and/or for social reasons (Ortiz, 2019).

Let’s explore what “gap-filing” means as a function of code-mixing. Sometimes young children don’t have certain vocabulary words in one of their two languages (Junker, et al., 2002). When this happens, they fill in the word from the other language into their sentence(s). This is something that happens in their L1 as well as their L2. This happens because there are two “types” of language that kids learn to use: social language and academic language. Social language is what we use in a typical, daily conversation with friends and family while academic language is more specific sets of vocabulary for subjects learned in an academic setting (i.e. at school) (Robinson, Westby, Robinson, & Westby, 2009). Bilinguals’ L1 might have more social language while L2 has more of the academic language since L1 might be the dominant language at home (Genesse, 2002). Often, young bilingual children’s L1 consists of more vocabulary words for household items and words to describe daily routines (e.g. bedtime). In general, a child’s L2 might consist of more academic words such as vocabulary terms for numbers, colors, shapes, days of the week/months, etc.

Now imagine you have a bilingual child in front of you. If you asked this child to explain what they’re learning in math, what language do you think they will use?

A conversation with a French-speaking child and her mother might look like this “Maman, j’ai appris comment faire long division aujourd’hui” [Mom, I learned how to do long division today.] When I speak in French, I will code-mix when I don’t have the word for a more technical term (think academic language) and will substitute the English word in my sentence.

Another function of code-mixing is for pragmatic reasons. Narration, emphasis, and protesting are a few of many pragmatic reasons for code-mixing (Genesse, 2002). We can become quite animated when telling a story such as taking on a different voice, raising our pitch, and changing our tone. For bilinguals, the purpose of code-mixing could be to imitate or quote someone in the story. And my personal favorite is how code-mixing can be used to emphasize a command or insistent on something.

This might look like a French-English bilingual saying “Dis-moi ! Tell me!” or “allez, on mange…come on, let’s eat.” 

A third function for code-mixing is for reasons related to social norms. For some cultural groups, code-mixing may be expected or tolerated to a certain degree. For example, code-mixing may be a demonstration of acculturation, class difference, or power relations (Ahmed, 2019; Genesse, 2002). This is an area which shows the importance of researching the culture and the language.

Now that we’ve covered some of the main functions of code-mixing, let’s talk about assessment. According to ASHA, all SLPs, monolingual and bilingual, “must be able to independently provide comprehensive diagnostic and treatment services for speech, language, cognitive, voice, and swallowing disorders including the client’s/patient’s language and preferred mode of communication” (American Speech-Language Hearing Association, 2020).  This is should not be ignored! Just because a child may speak English fluently or more often than their L1, does not mean that assessment in just English is sufficient enough (Bedore, Peña, Gillam, & Ho, 2010; Genesse, 2002; Peña, Bedore, Kester, 2015). The child’s language dominance is fluid—it will change over time and can do so quickly (Paradis, Nicoladis, Genesse, 2001).

At minimum, the following areas that should be evaluated/obtained in L1 and L2: vocabulary, narratives, language sample, and speech sample (Peña, Bedore, Kester, 2015).

Code-mixing is perfectly acceptable in assessment and can even be encouraged if it seems like the child is trying to only speak in their L1 or L2 (Bedore, Peña, Gillam, & Ho, 2010; Genesse, 2002; Peña, Bedore, Kester, 2015). This includes standardized testing. Code-mixed and other responses in either language should be accepted and given credit because research consistently supports the examination of both languages during assessment (Bedore, Peña, Gillam, & Ho, 2010; Peña, Bedore, Kester, 2015). Now you may ask “won’t this invalidate the test?” Yes, it will, but since most standardized assessments’ psychometrics don’t include your client’s CLD profile anyway, you should never report those scores in your report. You’re likely to see more code-mixing in a language sample with younger children, but it is totally normal to see it with older children and adults (Genesse, 2002). Considering the support for looking at abilities in both languages, does it make more sense how code-mixing gives you a better picture of overall language ability? Since code-mixing is rule-based and grammatical, the instances of code-mixing are mostly likely serving one of the functions mentioned above (Genesse, 2002).

Let’s look at an example from one of my language assessments with a French-English speaking child. She said “je veux [I want] the pink one,” which function of code-mixing do you think she was using? 

Vocabulary testing follows the same rules. Total vocabulary (from L1 and L2) must be counted and considered (Junker, et al., 2002). In an assessment with an older French-English client, I accepted vocabulary words in either language to get the most accurate picture of his vocabulary size. So, if there was a picture of a fish, an acceptable answer from him would be “fish” or “poisson.”

What about speech samples? How do they fit in? Even if you don’t speak the child’s first language, you can still access the sounds produced in their L1 and L2. ASHA provides resources for phonological sounds produced in other languages which are helpful for the preparation/interpretation of your assessment. This will help you identify which speech sounds might exist in L1 versus L2, or which overlapping sounds might develop at different times. It will also help you identify possible dialectal differences. This information is crucial for detecting a difference versus disorder.

Remember, the overall goal is to figure out if the client has a certain skill in either language, regardless of whether it is in L1 or L2.

Now let’s finish up with code-mixing and intervention. Code-mixing is powerful tool in treatment. Research findings showed that use of L1 in treatment can increase academic performance in L2 while helping them to maintain social, emotional, and academic performance in L1 (Kohnert, Yim, Nett, Kan, & Duran, 2005). It is important to note—there are other factors not discussed here that will contribute to the decision to do therapy in one or both languages, but in either case, code-mixing is okay and should be encouraged (Bedore, Peña, Gillam, & Ho, 2010; Genesse, 2002; Kohnert, Yim, Nett, Kan, & Duran, 2005; Peña, Bedore, Kester, 2015)!

In general, allow clients to fill in gaps using a word from L1 or L2. When conducting treatment with bilingual children, familiarize yourself with the words that they are most likely to know in their L1 and L2 (social vs. academic language). The ability to switch from one language to another is a natural ability. In my own language experiences, I am able to code-mix without thinking twice. Kohnert et al. (2005) cited systematic studies that supported the use of both languages in order to decrease some of the demand on the child and allow them to be more successful in the early stages of therapy.

In my own experiences with bilingual language intervention for a preschooler with receptive and expressive language deficits, I would model utterances and give a direction in both French and English. The child was exposed mostly to French at home and English at preschool. Initially, she was producing short and limited utterances, but very quickly she began expanding her utterance through code-mixing.

Remember that it isn’t enough to just know your client’s language. To be a culturally competent clinician, you need to explore potential biases and familiarize yourself with the cultures of your clients. Consider representation in your material selection. Is your client represented in the pictures you’ve chosen? Does it respect their cultural views? For example, certain cultures don’t eat pork, so on a vocabulary test, a child shouldn’t be penalized if they don’t recognize a picture of “bacon.” It’s important that your materials incorporate images of people who look like your clients in terms of skin color, religion, or differences in physical abilities. For a client of mine with Down’s syndrome working on pragmatic skills, I created a social story for him using people from his racial background and included people with Down’s syndrome. He and his mother loved it! Another important cultural consideration to explore is how your client’s culture may view disabilities/disorders to best engage in education and counseling. This also helps facilitate conversations about decisions on goals and treatment design. Finally, don’t assume anything about your client based on their linguistic and cultural background. Use ethnographic interviewing and dynamic assessment to obtain bias-free information about your clients.

The best part about our profession is how it is always growing and evolving, just like us! Keep seeking out information about cultural and linguistic diversity; your clients will thank you for it!


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American Speech-Language-Hearing Association. (2020). Demographic profile of ASHA members providing bilingual services, year-end 2019. Available from

Bedore, L. M., Peña, E. D., Gillam, R. B., & Ho, T.-H. (2010, May). Language sample measures and language ability in Spanish-English bilingual kindergarteners. Retrieved from

Ortiz, J. (2019, June). Bilingual Development

Junker, D. A., Stockman, I. J., Junker, D. A., Junker, D., Stockman, I. J., & Department of Audiology and Speech Sciences Michigan State University Google. (2002, November). Expressive Vocabulary of German-English Bilingual Toddlers. Retrieved from

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Robinson, L., Westby, C., Robinson, L., & Westby, C. (2009, June). Social or Academic Language Intervention? You Don’t Have To Choose. Retrieved from, I. G., Rodríguez, B. L., & Payne, K. T. (2018, February). Cultural Competence: How Qualified Are You? Retrieved from

About The Author

Alexis Baione is a graduate student in the Hearing and Speech Sciences department at the University of Maryland.  She is a member of the Cultural-Linguistic Diversity Emphasis Program and the Bilingual Certificate Program (French). Her clinical interests include cross-linguistic speech and language therapy, fluency disorders, specific language impairment, and swallowing disorders.