Why classical test theory remains important in modern pre-employment assessments

24 November 2023

Over the past few decades methods of evaluating and selecting the right talent have evolved significantly – Classical Test Theory has remained its key component. Psychometric testing is a cornerstone of recruitment assessments, employing rigorous methodologies rooted in Classical Test Theory and, more recently, Item Response Theory.

In this article we will explain the meaning of these theories and its application psychometric testing in an easy and digestible way – designed as a must read for all recruiters and HR professionals.

We’ll also explore how psychometric testing is constructed into job assessment tools. Moreover, we’ll provide practical guidance to the interpretation of psychometric test scores for recruiters like yourself. Next, we will address common challenges faced in the field of psychometric testing, as well as outline the emerging trends that are shaping the future of psychometric testing in recruitment. 

This comprehensive overview will equip you with the knowledge needed to correctly choose and apply psychometric tools in your future recruitment campaigns.

Contents:

1. What is Classical Test Theory and why is it important in candidate assessment?
2. What are the key concepts of Classical Test Theory?
3. How are psychometric tests developed?
4. What are the benefits of using hiring assessments based on Classical Test Theory?
5. What are some of the common challenges with psychometric testing?
6. How to understand psychometric test scores as a recruiter?
7. What are the emerging trends in psychometric testing?
8. Why choose psychometric tests designed by Assess Candidates?
9. FAQs and Glossary of Terms

1. What Is classical test theory and why is it important in candidate assessment?

What is Classical Test Theory (CTT)?

Classical Test Theory (CTT) is a psychometric framework that focuses on the principles of test reliability and test validity. It provides a structured approach to designing, administering, and interpreting psychometric tests.

Understanding CTT and its significance is pivotal for recruiters and organizations when selecting pre-employment tests. Here’s a breakdown of what CTT is and why it matters.

What is the difference between Classical Test Theory and Item Response Theory?

Classical Test Theory (CTT) and Item Response Theory (IRT) are two distinct frameworks used in psychometric testing, each offering unique perspectives:

1. Classical Test Theory (CTT): CTT focuses on overall test characteristics, emphasizing concepts like test reliability and validity. It evaluates test performance as a whole, making it simpler to grasp and apply. CTT assumes that the measurement error is constant across all levels of the trait being assessed.

2. Item Response Theory (IRT): IRT, on the other hand, centers on individual test item properties. It assesses how each item contributes to measurement precision and can accommodate varying levels of item difficulty and discrimination. IRT provides a more nuanced understanding of item performance and is particularly useful when dealing with complex, adaptive testing scenarios.

In summary, while CTT examines the overall test’s reliability and validity, IRT delves into item-level properties, offering a more detailed and flexible approach, especially in situations where individual item characteristics play a critical role in job assessment precision.

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2. What are the key concepts of Classical Test Theory?

We have covered how Classical Test Theory (CTT) provides a structured framework for understanding the reliability and validity of psychometric job assessments – but to grasp the essence of CTT, it’s essential to delve deeper into its core concepts.

Key Concepts of Classical Test Theory Explained:

• Test Reliability: Test reliability signifies the extent to which a test produces consistent results when administered repeatedly to the same individuals under similar conditions. It quantifies the proportion of true score variance to total observed score variance. A reliable test minimizes measurement error and ensures that observed differences in scores are not merely due to chance or fluctuations.

• Test Validity: Validity signifies the degree to which a test accurately measures the specific trait, skill, or attribute it intends to assess. It validates whether the test outcomes correspond to the construct being measured, making it a critical concept for ensuring that hiring assessments align with the job requirements.

• True Score: The true score represents an individual’s actual standing on the trait or attribute of interest, uncontaminated by measurement error. CTT aims to estimate this true score as accurately as possible.

• Measurement Error: Measurement error accounts for the variability introduced by various factors, including test administration, scoring, and individual fluctuations. Minimizing measurement error enhances the reliability and validity of a test by ensuring that scores closely reflect the true score.

• Standard Error of Measurement (SEM): SEM quantifies the precision of a test by estimating the standard deviation of measurement error. Smaller SEM values indicate greater precision, enabling more accurate differentiation between individuals.

These key CTT concepts serve as the building blocks for developing, interpreting, and using psychometric tests effectively in recruitment and other fields.

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3. How are psychometric tests developed?

The development of psychometric tests is a meticulous process rooted in the principles of Classical Test Theory (CTT) and, in some cases, Item Response Theory (IRT). As a recruiter, you should be familiar with the following steps of psychometric test development.

8 steps of psychometric test development:

1. Test Construction: The process begins with clear test construction. Test developers define the constructs they aim to measure, ensuring alignment with the intended purpose of the assessment. 

2. Item Development: Items or questions are carefully crafted to assess the targeted attributes or skills. Item analysis techniques are employed to assess item quality, ensuring that each item contributes meaningfully to the assessment.

3. Standardization:To maintain consistency and fairness, tests are standardized. This involves setting uniform administration procedures and scoring guidelines.

4. Pilot Testing: Before finalizing the test, a pilot phase is conducted to gather data and assess the test’s reliability and validity. This phase should include a diverse sample of participants.

5. Reliability Assessment: Test developers calculate reliability coefficients to measure the degree of consistency in test scores. High reliability indicates that the test produces stable results.

6. Validity Evaluation: The validity of the test is rigorously assessed to ensure that it accurately measures the intended constructs. This involves examining the relationship between test scores and external criteria.

7. Psychometrics Research: Throughout test development, continuous psychometrics research is essential. Researchers refine the test based on empirical data and insights gained from the pilot phase.

8. Test Scores Interpretation: Developers provide guidelines for test scores interpretation, helping users understand the meaning of test results in practical terms.

In conclusion, the development of psychometric tests is a comprehensive process that combines elements of CTT and, in some cases, IRT. By following these steps and adhering to rigorous measurement theory, developers create robust hiring assessment tools with high reliability and validity, enhancing their utility in candidate recruitment.

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4. What are the benefits of using hiring assessments based on Classical Test Theory?

In candidate assessment, Classical Test Theory (CTT) ensures that psychometric tests used in the selection process are trustworthy and robust. CTT helps companies make informed decisions about candidate performance and suitability for roles.

Consider providers with pre-employment tests rooted in research-backed theory for your future hiring campaigns. Here are some quickfire benefits for doing so.

5 key benefits of selecting pre-employment assessment tests based on Classical Test Theory:

1. Reduction of Bias: Classical Test Theory helps reduce biases in candidate assessment by providing a standardized and objective approach to candidate evaluation. This reduces the potential for subjective judgments and discriminatory practices.

2. Quality Assessment Tools: Classical Test Theory serves as a cornerstone for developing high-quality assessment tools. By adhering to CTT principles, recruiters can create pre-employment assessments that are both reliable and valid, enhancing their effectiveness in identifying top talent.

3. Reduced Recruitment Costs: Classical Test Theory (CTT) helps create pre-employment assessments that effectively screen and evaluate candidates, minimizing the need for extensive and costly interview processes. This streamlined selection process saves both time and resources.

4. Minimized Retesting: Pre-employment assessments developed using Classical Test Theory (CTT) are more reliable and consistent, reducing the likelihood of retesting candidates. This saves the costs associated with administering assessments multiple times.

5. Improved Employee Retention: Accurate hiring assessments based on Classical Test Theory (CTT) lead to better hiring decisions, which in turn reduce turnover rates and the costs associated with recruitment and training of new employees.

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5. What are some of the common challenges with psychometric testing?

While psychometric testing rooted in Classical Test Theory offers valuable insights, it is important to remember no pre-employment assessment methodology is 100% infallible. Here are some of the challenges you may face when administering assessment tests for recruitment in your organization.

What are the challenges with psychometric testing?

Challenge with Psychometric Testing	Solution
Bias and Fairness: Ensuring that tests are unbiased and fair across diverse populations is a persistent challenge. Tests may inadvertently favor certain demographic groups, leading to unequal opportunities.	Select a provider who can provide a more appropriate and customizable norm group based on your candidate pool. This way, candidates are compared against people similar to them and percentile scores are more reflective.
Test Quality: Developing high-quality tests that are both reliable and valid demands expertise and resources. Poorly designed tests can result in inaccurate hiring assessments.	Simply select those who go the extra mile to do this. We pride ourselves on our chartered psychologists and experienced developers to ensure pre-employment test quality.
Test Anxiety: Test-takers may experience anxiety, affecting their performance. Managing candidates’ test anxiety is essential for accurate results, therefore aim to provide as much information as possible to candidates about their upcoming assessments and what is expected of them.	Encourage candidates in your email invite to take practice pre-employment tests beforehand. This way, you reduce anxiety and increase familiarity to allow candidates to present their true performance.
Cultural Sensitivity: The design of the test must avoid misinterpreting responses based on cultural differences in language, norms, and values.	As above, customizable norm groups help you ensure apples are compared with apples. It is paramount you are fair in interpreting candidate scores and only compare their scores with similar people.
Adaptation for Disabilities: Adapting tests for individuals with disabilities or special needs needs to be ensured for fair assessment.	Providers can provide time increases to cater for all. Additionally, the colors red and green can be avoided for color-blindness and zoom functionalities can be incorporated to allow candidates to focus in on assessments as required. Check for this beforehand to make an informed decision.
Test Security: Maintaining test security to prevent cheating and unauthorized distribution is an ongoing concern for many companies. Using lesser known providers might be an answer.	Providers can randomize pre-employment assessments and may also have cheater detection functionality. For example, preventing copy and paste and keeping strict time limits to make cheating more difficult.
Evolving Job Market: As job roles evolve, keeping tests up-to-date to measure relevant skills and competencies is a must for all organizations.	Opt for a provider with options to bespoke assessments to your organization. At Assess Candidates, we pride ourselves on building an assessment process catered to you. Bespoke assessments exist to ensure candidate assessments are more catered to your organization.
Ethical Considerations: Ethical dilemmas arise in data privacy, consent, and the use of psychometric results in decision-making.	Opt for a provider that allows you to adjust the minimum score required to progress a candidate. We suggest low-cut offs to prevent adverse impact and keep your hiring assessment process legally defensible.

Addressing these challenges requires ongoing research, adaptation of testing practices, and a commitment to fairness, ethics, and continuous improvement in the field of psychometric testing.

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6. How to understand psychometric test scores as a recruiter?

Now that you know the benefits of using hiring assessments rooted in theory, as a recruiter, the next step you will be most likely to carry out is understanding candidate results. It is essential for making informed hiring decisions. Here’s a brief guide to psychometric scoring.

5 tips to understand psychometric test scores:

1. Score Interpretation: Begin by reviewing the test’s score interpretation guidelines provided by the test developer. This typically includes the range of scores and their corresponding meanings.

2. Norms and Percentiles: Compare an individual’s score to the test’s norms or percentiles. This provides context by indicating how the individual’s performance compares to a reference group.

3. Cut Scores: In some cases, there may be predetermined cut scores that define different performance categories, such as “above average” or “below average.”

4. Consult Experts: If available, consult with experts or psychometricians who can provide deeper insights into score interpretation, especially in complex testing scenarios.

5. Consider the Context: Always consider the specific context in which the test is used. A score that is acceptable in one situation may not be in another.

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7. What are the emerging trends in psychometric testing?

As a recruiter, it is also a good idea to stay ahead of the psychometric pre-employment tests you are interpreting.

The field of psychometric testing in candidate assessment is not stationary – whilst we have seen the concerns of this method, the landscape of psychometric testing is continually evolving to meet the changing demands of the modern world.

Several emerging trends are shaping the field. Stay up to date with these to ensure your future candidate assessment campaigns are a success.

What are the most important new trends in psychometric testing for recruitment?

• Digital Assessments: The shift toward digital platforms for test administration is becoming more pronounced. Online and computer-based assessments offer convenience, scalability, and real-time scoring.

• Adaptive Testing:  Adaptive testing tailors the difficulty of questions to a test-taker’s ability level, providing more precise results and shorter testing times.

• Big Data and AI: Psychometrics is harnessing big data and artificial intelligence to analyze vast datasets for deeper insights into test performance and predictive analytics.

• Gamification: Introducing game-like elements to assessments can enhance engagement and candidate experience, especially among younger generations.

• Emotional Intelligence Assessment: There is growing interest in assessing emotional intelligence and interpersonal skills, as these attributes gain prominence in workplaces.

• Remote Proctoring: Innovations in remote proctoring technologies are addressing test security concerns in online assessments.

• Neuroscientific Insights: Understanding how the brain processes test-taking can lead to more effective assessments and personalized feedback. These are especially important in Game-based Assessments where many more behavioral data points can be captured.

These emerging trends reflect the dynamic nature of psychometric testing, adapting to new technologies, societal changes, and a deeper understanding of human behavior and cognition.

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8. Why choose psychometric tests designed by Assess Candidates?

At Assess Candidates we dedicate our careers to offer inclusive and reliable hiring assessment tools rooted in Classical Test Theory, with an aim to changing change hiring assessments so they are a seamless and enjoyable experience for both recruiters and candidates. 

We offer:

• Cutting-Edge Solutions: Access state-of-the-art psychometric testing solutions.

• Scalability: Streamline your recruitment or educational processes with digital assessments.

• Real-Time Results: Get instant insights into candidate performance.

• Ethical AI: Prioritize data privacy and fairness in assessment.

• Expertise: Benefit from our team’s proficiency in test development and interpretation.

• Informed Decisions: Make accurate and unbiased hiring decisions.

• Efficiency: Streamline your selection and evaluation processes.

• Stay Ahead: Partner with us to stay at the forefront of psychometric testing trends.

Practical example of how Assess Candidates will help your company design successful recruitment campaigns.

Problem

As a recruiter, you struggle with using online tools and have in the past had hires that did not fit well into your company culture and could not meet job requirements.

Assess Candidates Solution

With Assess Candidates as your partner, you can choose from an end-to-end range of assessments rooted in Classical Test Theory. With everything done in-house, you can be confident your hires will have a good job fit that enables them to perform better, stay longer and remain happier in your organization.

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9. FAQs and Glossary of Terms

FAQ (Frequently Asked Questions)

1. What Is Psychometric Testing, and Why Is It Important in Candidate Recruitment?
   • Psychometric testing is a method of assessing candidates’ cognitive abilities, personality traits, and skills objectively. It’s crucial in recruitment to make informed hiring decisions based on standardized measures, reducing subjectivity and bias.

2. What Are the Key Concepts in Classical Test Theory?
   • Classical Test Theory (CTT) focuses on test reliability and validity. Reliability ensures consistent results, while validity ensures accurate measurement. Understanding these concepts is vital for developing trustworthy assessment tools.

3. What is Item Response Theory (IRT)?
   • Item Response Theory (IRT) is a statistical framework used in educational and psychological testing to assess the performance of test items and the abilities of test-takers. It models the probability of a correct response to a test item as a function of both the item’s characteristics and the test-taker’s abilities.

4. How Are Psychometric Tests Developed?
   • Developing psychometric tests involves constructing items, standardizing tests, pilot testing, assessing reliability and validity, and continuous psychometrics research to refine assessments based on empirical data.

5. How are Percentile Scores calculated, and what do they represent?
   • Percentile scores rank an individual’s performance relative to a reference group. To calculate a percentile score, the number of people in the reference group who scored lower than the individual is determined, and this count is expressed as a percentage of the total reference group. For example, if a candidate scores in the 75th percentile on a test, it means they performed better than 75% of the people in the reference group. It’s a useful way to understand where you stand compared to others.

6. What is Ethical AI, and why is it important?
   • Ethical AI refers to the development and deployment of artificial intelligence systems in a manner that aligns with ethical principles, fairness, and societal values. It’s crucial because AI can have significant societal impacts, including bias, discrimination, and privacy violations. Ethical AI aims to ensure that AI technologies are designed and used responsibly, respecting human rights and avoiding harm to individuals or marginalized groups. It promotes transparency, accountability, and the equitable treatment of all users and stakeholders in the AI ecosystem.

Glossary of Terms

• Psychometric Testing: The practice of objectively assessing individuals’ abilities, personality traits, and skills using standardized measures.

• Classical Test Theory (CTT): A framework that emphasizes test reliability (consistency of results) and test validity (accuracy in measurement).

• Test Reliability: The degree to which a test produces consistent results upon repeated administrations.

• Test Validity: The extent to which a test accurately measures the specific trait or skill it intends to assess.

• Standardization: The process of setting uniform administration and scoring procedures to ensure fairness and consistency in testing.