The DRT is a group-administered test of cognitive skills, divided into two subtests, Verbal Reasoning and Numerical Ability.  Verbal Reasoning assesses the ability of students to understand, think and reason in and with words.  Four types of items contribute to the Verbal Reasoning subtest: Synonyms, Classifications, Analogies and Antonyms. Numerical Ability requires the student to reason with numbers and to manipulate numerical relationships, and is assessed using four types of items: Operations with Numbers, Relations among Numbers, Sequential Ordering, and Numerical Abstractions.

The DRT was standardised on nationally representative samples of over 6,000 students ‎enrolled in the target grades in Irish primary and post-primary schools in 2016. The DRT is ‎now intended mainly for delivery on the ERC’s computer-based testing platform, and five ‎parallel Forms of the test are available on that platform. However, one Form is also available ‎on paper. It is possible to compare results from the digital and paper versions, meaning that ‎schools can opt to test using a mixture of digital and paper tests, should they choose.‎

The Numeric Ability test requires minimal understanding of written English and can be administered to students with quite limited English language proficiency.

There are five Forms of the DRT, each of which is randomly assigned to students in a class group, thereby ensuring a wide content coverage and minimising opportunity to copy. Once a test is completed, the ERC DOTS platform automatically scores and scales the results, providing student and class group reports that are directly comparable across Forms. The ERC is also developing an Abstract Reasoning subtest, which will eventually be added to the DRT as an optional add-on. All content was developed in Ireland, specifically for Irish students.