Adapt-G test battery
The Adapt-G ability battery was developed according to Item Response Theory principles. It is a three-parameter IRT test and was originally developed on a custom IRT platform This platform was compared to a widely used IRT platform called Concerto, and the two engines were found to function virtually identically. To take advantage of the advances on the Concerto platform, the Adapt-G item bank will be migrated to Concerto, which is open source and developed and maintained by world-leading psychometricians.
What the Adapt-G measures
- Verbal Reasoning
- Numerical Reasoning
- Abstract Reasoning
Not the same as the GRT2
The abilities measured are the same as the GRT2. However, it is important to realise that the tests are not directly comparable. The Adapt-G draws on a much larger and more varied item bank, and is designed to measure across a wider range of ability levels.
While IRT tests are assumed to be distribution-free (not requiring norms), it was found to be necessary to calibrate the reporting of the Adapt-G to South African samples. This will be done periodically.
However, it is important when giving feedback to respondents and management, and when interpreting and making decisions, that you should not regard the Adapt-G as an equivalent test to the GRT2. They measure the same constructs but they are not scale-equivalent.
Background to the release of the Adapt-G
While the Adapt-G had been in use internationally for several years, it was only launched in South Africa during the Covid-19 pandemic of 2020. The pandemic and social distancing regulations had intensified the need for tests, including ability tests, that could be administered online without supervision under circumstances where testing people in person would expose professionals as well as respondents to a deadly disease.