CAT type psychometric tests

Evolving computer technologies, which have lead online psychometric tests to become common practice in employee recruitment today, have now extended to further enhance online psychometric testing capabilities. Computerised adaptive testing (CAT) is a relatively new and widely accepted method of online psychometric testing, used in various areas including employee recruitment. Psychometric tests which are based on CAT include, aptitude tests, reasoning tests, verbal reasoning tests and numerical reasoning tests. Online psychometric tests have many advantages over traditional paper-based tests, such as reduced administration time. However the use of CAT in psychometric testing opens up new possibilities and provides further advantages, such as further reduced test-taking time, and increased reliability for measuring candidates’ aptitude (Forbey & Porath, 2007). 

CAT reduces the number of items in online psychometric tests, by optimally adapting items to the individual test-taker (Fetzer & Meade, 2008). Whilst there are differences between CAT and traditional online psychometric tests, practicing for psychometric tests which are built on CAT is identical to practicing for other forms of online psychometric tests. Most of the differences between online psychometric tests and CAT psychometric tests include the science working behind the scenes.

This science is referred to as Item response theory (IRT), which is the most common psychometric approach to CAT ability and achievement forms of psychometric testing. This adaptive approach is designed to estimate the test-takers ability (or variable of interest to the employee selection panel), by adaptively choosing new items for the individual test-taker, based on the estimate of his/her knowledge, skill, ability, or other characteristic being evaluated by the test, obtained from previous responses. That is, in online psychometric tests based on CAT, a computer selects the items from an item bank that are most relevant for and informative about the ability of the particular test-taker, thus optimising test relevance and precision and reducing test-taking time. CAT psychometric tests balance accuracy with efficiency. The intention of this type of psychometric testing is to provide a challenging and motivating situation for the test-taker. CAT aims to produce unique psychometric tests, best-fitted to the individual test-taker, to produce optimal and precise responses.

Although the psychometric testing properties and science behind CAT are quite complex, the process, as experienced by the individual test-taker, is not. So how does CAT work in an online psychometric test? If you get an item correct, the computer selects a harder item and administers it next. If you get an item wrong, the computer selects an easier item to go next. This process continues until either the computer has enough information to produce a reliable psychometric test score or the test taker has reached the maximum number of items to be administered, whichever comes first. This process is described as item matching.

In summary, this approach has a number of advantages over the paper-and-pencil psychometric testing approach and the traditional fixed-item online psychometric testing approach. Practicing online psychometric tests based on CAT is the same as practicing for traditional online psychometric tests. CAT psychometric tests are also computer-based, and are predominantly administered online. Predominantly, CAT psychometric tests are administered via a keyboard or a touch screen, thus online practicing for these types of psychometric tests is ideal.