- vocabulary measurement in bilingual children

About CLTs

30 Languages






New papers using CLTs!

12 June 2018
New paper on relation between CLT scores and parental assessment Abbot-Smith et al. has been published in Child Language Teaching and Therapy!

12 October 2017
New paper on CLT application in bilingual children by Hansen et al. has been published in International Journal of Bilingualism!

30 June 2017
Six new papers using CLTs in different languages have been published in a special issue of Clinical Linguistics and Phonetics, and are available at the journal website and desribed in the editorial by Hanne Gram Simonsen and Ewa Haman!

15 August 2015
A paper describing the results of the AoA study done as a part of CLTs construction was published in the Behavior Research Methods. See the online version of the paper here.

Growth of CLT picture base

13 June 2017
The picture base has been widen by 17 new variants of the pictures.

Workshop in Bratislava

11 December 2015
It was a pleasure for us to host over 140 people on the conference in Bratislava! You can find some photos and materials from the conference: here.


CLTs are picture-choice and picture naming tasks. CLTs comprise four parts: comprehension and production of nouns and verbs. For cross-linguistic comparison CLT is not translated, but constructed for each language according to a set of rules based on each word’s semantics, age of acquisition, and phonological and grammatical complexity.
CLTs may be used in research with monolingual and bilingual participants in preschool age.


29 ready versions

6 computer versions

1 version in progress



Arabic (Lebanese)

1: Messarra, Kouba-Hreich, Haman & Łuniewska
2 (used in research): Khoury Aouad Saliby, Kouba-Hreich & Messarra


Gureghian, Abboud & Tuller


Gavarró & Montes


Łuniewska & Smolík


van Wonderen, Blom, Boerma, Janssen, Unsworth & van Dijk

English (British)

Haman, Łuniewska, Polisenka, Mieszkowska & Chiat

English (South African)


English (American)

Haman, Miller, Wodniecka, Koegler & Łuniewska




Rinker & Gagarina


Armon-Lotem & Harel


Ehret & Marton




Roch, Levorato & Tedeschi


Southwood & Potgieter


Blažienė, Dabašinskienė & Łuniewska


Engel de Abreu, Gilles, Łuniewska & Haman


Yap, Razak, Treffers-Daller, Łuniewska & Haman


Gatt & Łuniewska


Simonsen, Hansen & Łuniewska




Haman, Łuniewska, Pomiechowska, Szewczyk & Wodniecka


1 (used in research): Gagarina & Nennonen
2: Nenonnen

Scottish Gaelic

Chondrogianni & Butcher


1: Vuksanović & Bjekić
2: Anđelković, Popović & Savić


Kapalková, Slančová




Ringblom, Håkansson & Lindgren


Unal, Uncer & Ege

Learn more about using CLTs in your research or designing a new CLTs version! clts@psych.uw.edu.pl

Steps of construction

CLTs construction comprises five steps. The procedure differs slightly - at the first step - for the languages that were included in the Bi-SLI project, and for new languages. The steps aim to select the set of words, assess the words' difficulty, compose CLTs on the basis of words' difficulty and semantics, and pilot the CLTs.

Naming study

Aim: to prepare a list of words
Task: to recruit at least 20 native speakers who will name 300 pictures
Result: the most widely shared names given to the pictures will compose the list of words used in the next steps
Link: here

AoA study

Aim: to estimate words' difficulty
Task: to recruit at least 20 native speakers who will give AoA ratings for the 300 words
Result: the average rating for each word will be used as one of the difficulty measures
Link: here


Aim: to estimate words' difficulty
Task: to provide information on words' morphological and phonological characteristics
Result: the indices computed for the words will be used as the second measure of words' difficulty


Aim: to design the CLTs
Task: to construct the CLTs on the basis of words' AoA and complexity
Result: the pilot version of the CLTs is ready!

Pilot study

Aim: to revise the pilot CLTs
Task: to test 10 monolingual preschoolers with the CLTs and to revise their construction
Result: the final version of the CLTs is ready!

People use in research!

Swedish mono- & bilinguals

BiLi-TAS project, Uppsala University, Sweden
PI: Ute Bohnacker
PhD students: Rima Haddad, Linneá Öberg, Buket Öztekin
Languages: Swedish, Turkish, Lebanese/Arabic

Natalia Ringblom: Russian-Swedish bilinguals
Josefin Lindgren: Swedish-German bilinguals & Swedish monolinguals

German bilinguals

MiKuS project, University of Konstanz, Germany
PIs: Tanja Rinker & Janet Grijzenhout
Languages: German, Turkish, Italian, Polish, English

Polish bilinguals

University of Warsaw, Poland
Languages: Polish, Norwegian, English, Italian, German
PI: Ewa Haman
PhD students: Magdalena Łuniewska, Joanna Kołak, Karolina Mieszkowska

Polish-Norwegian: collaboration with Hanne Simonsen & Pernille Hansen, University of Oslo

Hungarian mono- & bilinguals

PI: Klara Marton
MA students: Judit Banhidi, Edit Peto

Slovak monolinguals

Comenius University, Bratislava
PI: Svetlana Kapalková

Maltese-English bilinguals

University of Malta
PI: Daniela Gatt
Languages: Maltese, English

Publications about

CLTs design

Haman, E., Łuniewska, M., & Pomiechowska, B. (2015). Designing Cross-linguistic Lexical Tasks (CLTs) for bilingual preschool children. In S. Armon-Lotem, J. de Jong & N. Meir (Eds.). Methods for assessing multilingual children: disentangling bilingualism from Language Impairment. Bristol: Multilingual Matters.

CLTs applications

Abbot-Smith, K., Morawska-Patera, P., Łuniewska, M., Spruce, M., & Haman, E. (2018). Using parental questionnaires to investigate the heritage language proficiency of bilingual children. Child Language Teaching & Therapy, 34(2), 155-170. DOI

Altman, C., Goldstein, T., & Armon-Lotem, S. (2017). Quantitative and qualitative differences in the lexical knowledge of monolingual and bilingual children on the LITMUS-CLT task. Clinical Linguistics & Phonetics, 0(0), 1–24. DOI

Bohnacker, U., Lindgren, J., & Öztekin, B. (2016). Turkish- and German-speaking bilingual 4-to-6-year-olds living in Sweden: Effects of age, SES and home language input on vocabulary production. Journal of Home Language Research 1, 17-41.

Gatt, D., Attard, D., Łuniewska, M., & Haman, E. (2017). The effects of bilingual status on lexical comprehension and production in Maltese five-year-old children: A LITMUS-CLT study. Clinical Linguistics & Phonetics, 0(0), 1–30. DOI

Haman, E., Łuniewska, M., Hansen, P., Simonsen, H. G., Chiat, S., Bjekić, J., … Armon-Lotem, S. (2017). Noun and verb knowledge in monolingual preschool children across 17 languages: Data from cross-linguistic lexical tasks (LITMUS-CLT). Clinical Linguistics & Phonetics, Online First(0), 1–26. DOI

Hansen, P., Łuniewska, M., Simonsen, H., Haman, E., Mieszkowska, K., Kołak, J., & Wodniecka, Z. (2017). Picture-based vocabulary assessment versus parental questionnaires: A cross-linguistic study of bilingual assessment methods. International Journal of bilingualism, Online First, 1–20. DOI

Hansen, P., Simonsen, H., Łuniewska, M., & Haman, E. (2017). Validating the psycholinguistic aspects of LITMUS-CLT: Evidence from Polish and Norwegian. Clinical Linguistics & Phonetics, Online First, 1–21. DOI

Kapalková, S., & Slančová, D. (2017). The vocabulary profile of Slovak children with primary language impairment compared to typically developing Slovak children measured by LITMUS-CLT. Clinical Linguistics & Phonetics, 0(0), 1–17. DOI

Potgieter, A. P., & Southwood, F. (2016). A comparison of proficiency levels in 4-year-old monolingual and trilingual speakers of Afrikaans, isiXhosa and South African English across SES boundaries, using LITMUS-CLT. Clinical Linguistics & Phonetics, 30(2), 87–100. DOI

Saliby, C. K. A., Santos, C. dos, Hreich, E. K., & Messarra, C. (2017). Assessing Lebanese bilingual children: The use of cross-linguistic lexical tasks in Lebanese Arabic. Clinical Linguistics & Phonetics, 0(0), 1–19. DOI

Slančová, D., & Kapalková, S. (2013). Výskum vývinu detskej reči v slovenčine v medzinárodnom kontexte projektov COST. In: Jazyk a kultúra, (14).

CLTs construction steps

Age of acquisition

Łuniewska, M., Haman, E., Armon­Lotem, S., Etenkowski, B., Southwood, F., Andelkovic, D., ..., Unal - Logacev, U. (2015). Ratings of age of acquisition of 299 words across 25 languages. Is there a cross­linguistic order of words? Behavior Research Methods, 48(3), 1154-1177.

Theses using

Master Theses

Chyl, Katarzyna (2015). Vocabulary Size of Bilingual Preschool Children learning Polish as their first language. Unpublished master thesis. University of Warsaw, Faculty of Psychology. Supervisor: Ewa Haman.
Lindgren, Anna (2016). Cross-linguistic Lexical Tasks (CLTs): En kvalitativ analys av ordproduktion hos enspråkiga svenska och flerspråkiga svensk-turkiska 4;0-6;11-åringar. [Cross-linguistic Lexical Tasks (CLTs): A qualitative analysis of vocabulary production in monolingual Swedish and multilingual Swedish-Turkish 4;0 to 6;11-year-olds]. Unpublished master thesis (written in Swedish). Uppsala University, Department of Neuroscience, Speech-Language Pathology and Therapy Unit. Supervisor: Ute Bohnacker.
Markiewicz, Stefan (2014). Lexical Processing of Nouns & Verbs An Insight into Noun Bias in Polish Monolingual Preschool Children. Unpublished master thesis. University of Warsaw, Faculty of Psychology. Supervisor: Ewa Haman.
Poklembová, Terézia (2016). Analýza chýb v pomenovaní podstatných mien a slovies v predškolskom veku. Unpublished master thesis (written in Slovak). Comenius University. Supervisor: Svetlana Kapalková.
Sender, Camilla & Svensson, Malin (2017). Flerspråkiga barns felsvar vid bedömning av ordförrådet: En kvantitativ och kvalitativ studie kring ordförrådsutvecklingen hos svensk-turkiska 4- och 7-åringar via ordförrådstestet Cross-linguistic Lexical Task (CLT). [Multilingual children’s incorrect responses during vocabulary assessment: A quantitative and qualitative study of lexical development in Swedish-Turkish 4- and 7-year-olds on the CLT] Unpublished Master thesis (written in Swedish). Uppsala University. Department of Neuroscience, Speech Language Pathology & Therapy Unit. Supervisor: Ute Bohnacker.
Šašalová, Blanka (2016). Child language lexicon. Unpublished master thesis. Prešov University in Prešov, Faculty of Arts, Institute of Slovak and Media Studies. Supervisor: Daniela Slančová.
Valečíková, Barbora (2016). Overenie validity lexikálneho hodnotiaceho nástroja u detí v ranom veku. Unpublished master thesis (written in Slovak). Comenius University. Supervisor: Svetlana Kapalková.
Vrchovská, Zuzana (2015). Porozumenie a produkcia slov u detí vo veku troch do šiestich rokov pomocou lexikálneho testu. Unpublished master thesis (written in Slovak). Comenius University. Supervisor: Svetlana Kapalková.

Doctoral Theses

Lindgren, Josefin (2018). Developing narrative competence: Swedish, Swedish-German and Swedish-Turkish children aged 4-6. PhD thesis. Studia Linguistica 19. Uppsala: Uppsala University. Supervisor: Ute Bohnacker.
Łuniewska, Magdalena (2018). Vocabulary size and organization of the mental lexicon in typically developing children and children at risk of specific language impairment SLI. Unpublished PhD thesis. University of Warsaw. Supervisor: Ewa Haman.

Grants using


The method of designing CLTs was established in the project entitled "Language Impairment in a Multilingual Society: Linguistic Patterns and the Road to Assessment" funded by European Cooperation in Science and Technology (COST, IS0804). The project aimed at creating and testing basic tools for the assessment of the linguistic and cognitive development of bilingual children, which could later help establish crosslinguistic diagnostic norms.


The first steps of CLTs' design took place within Polish project Bi-SLI-PL (2010-2015) carried out at the Faculty of Psychology, University of Warsaw in collaboration with Institute of Psychology, Jagiellonian University in Kraków, led by Ewa Haman and Zofia Wodniecka. The project was financed by Ministry of Science and Higher Education and National Science Centre, Poland (decision 809/N-COST/2010/0). The University of Warsaw owns copyrights for the set of pictures designed for CLTs.

Kościuszko Foundation

Development of the American version of the CLTs was possible thanks to the project entitled "A new tool for testing vocabulary and lexical processing of bilingual children in American English" supported by the Kościuszko Foundation (scholarship awarded to Ewa Haman). The scholarship was pursued at the Centre for Language Sciences, Penn State University, USA, in collaboration with professor Judith Kroll and dr Zofia Wodniecka.

Visegrad Fund

Development of the CLTs in the Visegrad Group countries: Czech Republic, Hungary, Poland and Slovakia was possible in a project entitled "Bilingual assessment of child lexical knowledge: new method for Polish, Czech, Slovak and Hungarian" funded by International Visegrad Fund (standard grant). The project was supported by International Visegrad Fund with an amount of EUR13.000. In the project, we constructed the missing Czech and Hungarian CLTs according to multilingual construction procedure and conducted a validity study of CLTs testing materials in V4 countries.


The project entitled "Language impairment or typical language development? Developing methods for linguistic assessment of bilingual children in Sweden" is funded by the Swedish Research Council (2014-2019). In the project, various language versions (Swedish, Turkish, Lebanese) are used for testing Swedish-Arabic and Swedish-Turkish bilingual children.


In the project entitled "Mehrsprachigkeit in Kita und Schule" (MiKuS) - Multilingualism in day care and school (PIs: Tanja Rinker & Janet Grijzenhout), we are using the German, Italian and Turkish versions, as well as Polish and English. The funding is through Excellence funds of the University of Konstanz for transfer projects.

Slovak RDA

In the project entitled "Reading comprehension - enhancing through an inovative teaching method, creation and efficacy assessement using randomised controlled trial methodology", the computer version of Slovak CLT was used to assess vocabulary of 6 year-old Slovak speaking children (N = 200). Project was funded by Slovak Research and Development Agency (SRDA) for period 2012-2015.


Ewa Haman

Ewa is an assistant professor at the Psycholinguistics Lab, Faculty of Psychology, University of Warsaw. Her research interests are focused on lexical development of Polish-speaking children. Ewa has been a co-leader of the WG3 BiSLI COST. She is the first author of the CLTs design and the leader of the project.


Magdalena Łuniewska

Magdalena, PhD (2018, with honours), works at the Psycholinguistics Lab, Faculty of Psychology, University of Warsaw, and at the Nencki Institute of Experimental Biology, Polish Academy of Sciences. Magdalena co-authors the CLTs design procedure. She assists designers of various language versions in the process of CLTs construction. She coordinates the naming study and the AoA study.


Let's get in touch!

Interested in using CLTs in your research? Send us an email and we will get back to you as soon as possible!


Psycholinguistics Lab, Faculty of Psychology, University of Warsaw
Stawki 5/7, 00-183 Warsaw, Poland