General Intelligence Assessment (GIA) |

General Intelligence Assessment (GIA)

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General Intelligence Assessment (GIA)

Accurately predict a person's potential to grasp a new role

  • Predict success in a role
  • Recruit candidates who adapt & learn quickly
  • Create high performing teams
  • Keep your team engaged and inspired in their roles
  • Identify future high-performers
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The General Intelligence Assessment (GIA)

Aptitude has been widely acknowledged as the most important predictor of job success. The GIA, part of our team interaction optimisation (TIO) platform, can help you to identify who will perform best in a role and build high performing teams to improve business performance.

Why use aptitude

Why use the General Intelligence Assessment (GIA)?

Measuring the aptitudes of a candidate helps you to understand if that individual will be able to quickly grasp the requirements of the role. It can give you an insight into whether they have the capacity to adapt to new challenges, and if they would be suited to drive change through your organisation.

This insight makes it easier to select the right candidate for the role by placing an objective filter on their ability, regardless of their IQ score, qualifications, and past experience. That’s not to say that IQ, qualifications and experience are unimportant, but they’re not the best predictor of potential performance in a role.

It’s widely acknowledged that not everyone excels at school, and that results from standard national exams or industry-accepted tests aren’t the best way to understand an individual’s capabilities, the level of challenge they need to keep them stimulated and committed, or whether they will respond well to development activities.

Research by the American Psychology Association inc. Frank L. Schmidt & John E. Hunter (1998) reviewed 85 years of research and found that higher cognitive ability, or aptitude as it is also called, as measured by the Thomas Aptitude assessment, is directly linked to higher employee productivity and performance in role.

How the General Intelligence Assessment (GIA) works


The General Intelligence Assessment (GIA) measures an individual's aptitude in 5 key areas: Reasoning, Perceptual Speed, Number Speed & Accuracy, Word Meaning and Spatial Visualisation

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5 Online Assessments


The Thomas GIA test consists of 5 online assessments, including reasoning, perceptual speed, number speed and accuracy, word meaning and spatial visualisation.

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Detailed Understanding


Gain a detailed understanding of a person’s mental capacity and how quickly they can grasp a new role/regime with the Thomas GIA test.

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Understand General Intelligence

The overall percentile is an estimate of a candidate's general intelligence, while focusing on their response to training, mental processing speed, concentration and fast track potential.

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Assessment Information

  • Assessment type: Aptitude
  • Format: 5 assessments
  • Time to complete: 30-45 minutes
  • Training required: None


Registered with the British Psychological Society and audited against technical criteria established by the European Federation of Psychologists’ Associations

Click below to download a sample candidate profile from the Thomas Perform platform

We simply would not be where we are today without the GIA from Thomas. The feedback that these assessments provide is invaluable.

Simon Bastin-Mitchell - Silverlake
Simon Bastin-Mitchell
Commercial Manager
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Background & Theory

The GIA, also known as the Thomas Aptitude assessment, was first developed as a way to measure conscious intellectual abilities and trainability of Armed Forces known as the British Army Recruitment Battery (BARB). It was then developed by Dr Peter Dann and has been part of the Thomas suite since 2006.

Intelligence can be defined as having fluid and crystallised components:

  • Fluid intelligence (pure processing speed) – this is used to solve new problems, use logic in new situations and identify patterns.
  • Crysallised intelligence (learnt factors) – This is the ability to use learned knowledge and experience.

The GIA is concerned with fluid intelligence and looks at an individual’s speed of processing information and ability to learn and develop new skills, rather than measuring ‘IQ’.

Get our factsheet to learn how the Aptitude assessment can help you better understand the learning speed and trainability of your people

Aptitude format


The General Intelligence Assessment consists of five online tests that rely on processes such as thought, language, decision making, learning and memory.

Each test measures a different cognitive function (detailed below):

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This test measures the ability to make inferences, the ability to reason from information provided and to draw the correct conclusions. This test assesses the ability of an individual to hold information in their short-term memory and solve problems.

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Perceptual Speed

This test measures the perception of inaccuracies in written material, numbers and diagrams, the ability to ignore irrelevant information, the ability to recognise similarities and differences, and error checking. It tests the speed of semantic encoding and comparison.

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Number Speed and Accuracy

This is a test of numerical manipulation and a measure of basic numerical reasoning ability. It measures the degree to which an individual can work comfortably with quantitative concepts.

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Word Meaning

This test assesses word knowledge and vocabulary. It assesses the comprehension of a large number of words from different parts of speech and the ability to identify the words that have similar or opposite meanings. It assesses the ability to work in environments where a clear understanding of written or spoken instructions is required.

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Spatial Visualisation

This test measures the ability to create and manipulate mental images of objects. This test correlates with tests of mechanical reasoning, and assesses an individual’s ability to use mental visualisation skills to compare shapes. It relates to the ability to work in environments where visualisation skills are required to understand and execute tasks.

Behaviour Validity

Reliability & Validity

The GIA has been subject to rigorous scientific testing to determine its reliability and validity as a psychological assessment. Various research studies have shown that the GIA is a consistent and valid measure of trainability.

The GIA is registered with the British Psychological Society (BPS) after it was audited against the technical criteria established by the European Standing Committee on Tests and Testing, part of the European Federation of Psychologists' Associations.

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Frequently Asked Questions

What is the General Intelligence Assessment (GIA)?

The General Intelligence Assessment (GIA) is an aptitude and ability test (or perceptual speed test) that helps employers predict how quickly an individual will adapt to a new role or regime.

How does the GIA work?

The GIA is composed of online tests that measure an individual’s cognitive function in five areas: Reasoning, Perceptual Speed, Number Speed & Accuracy, Word Meaning and Spatial Visualisation.

Their score is determined by the speed and accuracy of their responses and then compared to a norm group to determine whether the scores are lower, higher or in-line with the majority of that population.

What are the benefits of the GIA to an organisation?

The GIA report gives you an estimate of an individual’s general intelligence and gives insights into their response to training, mental processing speed, concentration and fast track potential.

As a result, the GIA can help you answer questions about your workforce including, ‘Can your people think on their feet?’, ‘Can they cope with the mental demands of the job?’, ‘Are they good problem solvers?’ and ‘How quickly they can they learn?’.