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Instrument to Measure Toddlers’ Numerical Cognition (E-ZaBE): Standardisation and Validation

Background and aims

Development of an understanding of numbers (Zahlenbegriff, ZBE) begins as early as in the first months of life, and at school entry, a child usually possesses a solid basis of mathematics skills. However, there are also already great interindividual differences that have an impact on later mathematics achievement. Despite the importance of early ZBE, up to now there has existed no instrument to assess it in early childhood. The Erfassungsinstrument zur Zahlenbegriffsentwicklung für Kinder von 2 bis 5 Jahren (E-ZaBE) (Olshausen Urech, 2015) closes this gap. With this instrument, developmental delays in ZBE can be identified in children age 2 years and older, and development can be supported in early special education, childcare centres, and special education schools.


The research project examined typical development of ZBE in children with impairment or developmental delay age 2 to 4½ years and examined the psychometric criteria of the items and scales. The E-ZaBE was administered to a total of 273 children. To determine age-typical development of ZBE, students in the Master’s programme HFE [early years special education] examined 171 children in childcare centres. To assess delayed development, early special education professionals in the Canton of Bern tested 102 children with approval or voucher for early years special education.


The results showed that E-ZaBE is a suitable instrument for practical assessment of developmental delays in ZBE. The instrument has a continuously increasing degree of difficulty—starting with items on pre-numeracy skills such as one-to-one correspondence, to items on numeracy skills such as counting objects, to items on recognizing numerals—and provides a valid measurement of children’s development of ZBE from age 2 to age 4½. The sequence of ZBE is also found in children with impairment or developmental delay, with only one difference: Their scores correspond to those of the younger age group in age-typical ZBE. Core skills in ZBE were thus achieved with a delay of one year.

To gain more precise information on the age groups and the sequence of ZBE and to examine psychometric quality criteria, the sample is currently being expanded. In a follow-up study, students in the HFE Master’s programme are administering the E-ZaBE to children in childcare centres.



Project Management

Project team


Forschung und Entwicklung
Tel: +41 44 317 11 81

zfe[at] zfe