Investigating the differential item functioning of a PIRLS Literacy 2016 text across three languages

  • Karen Roux University of Pretoria
  • Surette van Staden UP
  • Elizabeth J. Pretorius UNISA
Keywords: differential item functioning, equivalence, large-scale studies, PIRLS Literacy 2016, reading comprehension, translation


The aim of this study was to determine whether a limited release literary text from the Progress in International Reading Literacy Study (PIRLS) Literacy 2016 is equivalent across English, Afrikaans and isiZulu, three of South Africa’s 11 official languages. PIRLS is a large-scale reading comprehension assessment, which assesses Grade 4 students’ reading literacy achievement. PIRLS Literacy 2016 results for South African Grade 4 students indicated poor performance in reading comprehension, with approximately eight out of ten Grade 4 students who cannot read for meaning.  Descriptive statistics informed the Rasch analysis which was conducted using the South African PIRLS Literacy 2016 data. Even though the Rasch analysis indicated differential item functioning across the three languages for this specific passage, there was no universal discrimination against one particular language. By conducting differential item functioning, it was possible to determine whether the selected text had metric equivalence, in other words, whether the test questions were of similar difficulty across languages.