Abstract:
ORIENTATION: For a number of years, eliminating a language component in testing by using
nonverbal cognitive tests has been proposed as a possible solution to the effect of groups’
languages (mother tongues or first languages) on test performance. This is particularly relevant
in South Africa with its 11 official languages.
RESEARCH PURPOSE: The aim of the study was to determine the differential item functioning (DIF)
and structural equivalence of a nonverbal cognitive ability test (the PiB/SpEEx Observance test
[401]) for five South African language groups.
MOTIVATION FOR STUDY: Cultural and language group sensitive tests can lead to unfair
discrimination and is a contentious workplace issue in South Africa today. Misconceptions
about psychometric testing in industry can cause tests to lose credibility if industries do not use
a scientifically sound test-by-test evaluation approach.
RESEARCH DESIGN, APPROACH AND METHOD: The researcher used a quasi-experimental design and
factor analytic and logistic regression techniques to meet the research aims. The study used a
convenience sample drawn from industry and an educational institution.
MAIN FINDINGS: The main findings of the study show structural equivalence of the test at a
holistic level and nonsignificant DIF effect sizes for most of the comparisons that the researcher
made.
PRACTICAL/MANAGERIAL IMPLICATIONS: This research shows that the PIB/SpEEx Observance Test
(401) is not completely language insensitive. One should see it rather as a language-reduced
test when people from different language groups need testing.
CONTRIBUTION/VALUE-ADD: The findings provide supporting evidence that nonverbal cognitive
tests are plausible alternatives to verbal tests when one compares people from different
language groups.
