Pioneering Contributions to Organizational Psychology: From World Wars to Workplaces

When the United States entered World War I in 1917, the military faced an unprecedented challenge: how to quickly evaluate millions of recruits and assign them to the right roles. The answer came not from generals or politicians, but from psychologists. This moment – when science met military necessity – gave birth to some of the most foundational practices in industrial and organizational (I/O) psychology. The contributions of figures like Robert Yerkes, James McKeen Cattell, and Walter Van Dyke Bingham during and after the World Wars didn’t just reshape the military. They transformed how organizations everywhere think about hiring, training, and managing people.

The urgency of World War I and the rise of psychological testing 🔗

Before World War I, psychological testing existed mostly in university laboratories and small clinical settings. There was no mechanism for evaluating large groups of people quickly. But with nearly two million recruits flooding into military camps, the U.S. Army needed a fast, systematic way to sort soldiers by their cognitive abilities and assign them to suitable roles.

Robert Yerkes, a Harvard professor and president of the American Psychological Association at the time, saw an opportunity. He convinced the Army that psychological testing could help with the massive task of personnel classification. Yerkes then assembled a committee of prominent psychologists – including Lewis Terman, Henry Goddard, and Guy Montrose Whipple – to develop group intelligence tests that could be administered at scale.

The result was two landmark instruments: the Army Alpha and the Army Beta tests. These weren’t just academic exercises. They were used across 35 military camps, administered by roughly 120 officers and 350 enlisted personnel, with over 500 additional clerks supporting the operation.

Army Alpha: testing literate recruits 🔗

The Army Alpha was a written, group-administered test designed for recruits who were literate in English. It assessed verbal ability, numerical reasoning, the capacity to follow directions, and general knowledge. Scores were used to determine a soldier’s capability for service, job classification, and potential for leadership. The test drew heavily on intelligence testing concepts pioneered by Alfred Binet, adapting them for rapid group administration rather than one-on-one assessment.

Army Beta: reaching those beyond written language 🔗

Not all recruits could read English. Many were immigrants with limited English proficiency, and others were illiterate. For these soldiers, the Army Beta was created – a nonverbal, pictorial test that relied on visual tasks and demonstrations rather than written instructions. Examiners used demonstration charts and mime to convey instructions, making it accessible regardless of language background. The Army Beta operated on a key assumption that was progressive for its time: that intelligence and literacy were independent of each other.

The scale and impact of the Army testing program 🔗

By the end of World War I, the numbers were staggering. Over 1.7 million soldiers had taken the Army Alpha or Army Beta. Approximately 83,000 individual follow-up examinations were conducted. Around 7,800 men were recommended for immediate discharge based on the results. Another 10,000 were assigned to labour battalions, and roughly 9,500 were flagged for additional observation and training.

This was the first large-scale use of psychological testing in history. It demonstrated that psychology could handle massive logistical challenges and produce results that genuinely influenced organizational decisions. The tests established a model for systematic personnel assessment that had never existed before.

Key psychologists who shaped the field 🔗

Robert Yerkes: bringing psychology to the military 🔗

Yerkes was the driving force behind the Army testing program. Working through the National Research Council, he proposed the idea of mass intelligence testing and then commissioned a team of 400 Army personnel to carry it out. His committee spent weeks at the Vineland Training School in New Jersey developing and trialling the tests before rolling them out nationally. After the war, Yerkes published the results through the National Academy of Sciences, making the data and methodology available to the broader scientific community. His work proved that psychological assessment had practical, real-world value far beyond the laboratory.

Walter Van Dyke Bingham: bridging academia and industry 🔗

Bingham’s contributions straddled both World Wars. In 1915, he founded the Division of Applied Psychology at Carnegie Institute of Technology – the first major academic program dedicated to applying psychology to business problems. The program offered entrance testing, vocational guidance, and research partnerships with local businesses. Bingham hired Walter Dill Scott to lead the Bureau of Salesmanship Research, and together they developed methods for selecting and training personnel using tools like personal history forms, structured interviews, and mental alertness tests.

During World War I, Bingham and Scott worked under the Adjutant General’s Office, focusing specifically on officer selection. They created a catalogue of occupational needs for the Army – essentially one of the first job-description systems – along with methods for performance ratings and occupational skill testing. When World War II arrived, Bingham was hired as the chief psychologist for the War Department, where he developed new systems for job selection, classification, training, and performance review.

James McKeen Cattell: from mental tests to the Psychological Corporation 🔗

James McKeen Cattell was one of the most influential figures in making psychology practically useful. A student of Wilhelm Wundt in Leipzig, Cattell later studied with Francis Galton in London before returning to the United States. Unlike Wundt, who focused on general laws of behaviour, Cattell was deeply interested in measuring individual differences and is credited with introducing the concept of the “mental test.”

At Columbia University, Cattell devoted much of his career to advancing mental testing and its applications. His most significant organizational contribution came in 1921, when he founded the Psychological Corporation. This organization had a dual purpose: to advance psychology as a science and to promote its practical usefulness to industry and business. It initially consisted of about 20 influential psychologists as directors and approximately 170 psychologists holding stock. The Corporation served as a bridge between academic research and the needs of the business world, helping companies find qualified psychologists and developing standardized psychological tests for hiring, placement, and performance evaluation.

Over the decades, the Psychological Corporation grew from a professional referral service into one of the world’s largest publishers of psychological tests. In 1969, it was absorbed into Harcourt, Brace, Jovanovich through a merger – a sign of just how commercially significant psychological assessment had become. Cattell’s vision of connecting scientific psychology with the practical needs of organizations essentially laid the groundwork for the entire field of applied psychological assessment.

The post-war transition: from battlefields to boardrooms 🔗

When World War I ended, the psychologists who had worked on military testing didn’t simply return to their universities and move on. They brought with them proven methods, credibility, and a track record of success. The techniques developed for sorting soldiers were quickly adapted for civilian use.

By the 1920s, updated versions of the Army testing framework were being used in schools to group students, in workplaces to screen job applicants, and in government agencies for hiring decisions. Bruce V. Moore received the first Ph.D. specifically in I/O psychology from Carnegie Tech in 1921, creating an early version of what would become the Strong Interest Inventory – a career-matching tool still used today. The field grew from roughly 10 practicing I/O psychologists in 1917 to 50 by 1929.

The Psychological Corporation played a key role during this period, not only as a publisher of tests but also as a quality control body. It helped protect the emerging field’s reputation by ensuring that businesses worked with qualified psychologists rather than untrained practitioners who were trying to capitalize on psychology’s growing popularity.

World War II: the next leap forward 🔗

If World War I proved that psychological testing could work at scale, World War II proved it could work with much greater sophistication. The military now needed tools that went beyond basic intelligence screening.

The Army General Classification Test (AGCT) 🔗

The AGCT replaced the Army Alpha and Beta and represented a major advancement. Developed starting in 1940, it measured verbal comprehension, quantitative reasoning, and spatial thinking – a more nuanced assessment than its World War I predecessors. The AGCT was used to classify approximately 12 million recruits during World War II, assigning them to over 200 different military occupational specialties.

Scores were converted into standard scores with a mean of 100 and divided into five grades. Grade I (scores of 130 and above) indicated soldiers suited for leadership and technical roles, while Grade V (below 80) suggested limited aptitude for complex tasks. Certain occupations had minimum score requirements – for example, the Air Corps required a score of at least 100 for pilots, navigators, and bombardiers.

Alongside the AGCT, the Navy developed the Navy General Classification Test (NGCT), which served a similar purpose and was administered to roughly three million sailors. Additional specialized tests covered mechanical aptitude, clerical skills, radio code operation, and language proficiency.

Assessment centres and the OSS 🔗

One of the most innovative developments of World War II was the creation of assessment centres by the Office of Strategic Services (OSS) – the precursor to the CIA. Rather than relying solely on paper-and-pencil tests, the OSS put candidates through realistic simulations. They observed how individuals handled complex, ambiguous, high-pressure situations, evaluating problem-solving ability, leadership under crisis, and teamwork with diverse groups.

This approach was groundbreaking. It moved assessment beyond measuring what someone knows to evaluating how they perform in realistic conditions. The assessment centre model developed during the war became the foundation for techniques that organizations from Fortune 500 companies to fire departments still use for leadership selection today.

The lasting legacy of wartime psychology 🔗

The contributions made during the two World Wars didn’t just stay in the military. They fundamentally reshaped how civilian organizations approach human resources and personnel management.

The concept that people should be selected for roles based on objective, standardized assessments rather than subjective impressions or personal connections – something we take for granted today – was established and validated through wartime testing programs. The idea that different jobs require different aptitudes, and that these aptitudes can be measured, became a core principle of modern hiring practices.

The AGCT itself evolved into the Armed Services Vocational Aptitude Battery (ASVAB), introduced in 1968 and still used by all branches of the U.S. military today. Beyond the military, the principles behind these tests influenced the development of college admissions testing (Carl Brigham, who worked on the Army Alpha, later created the SAT), corporate aptitude testing, and vocational guidance tools.

Bingham’s work on job classification systems during both wars set the template for how organizations define roles and match people to them. Cattell’s Psychological Corporation demonstrated that there was a viable business model in applied psychology, encouraging generations of psychologists to move beyond academia and work directly with organizations. And the wartime experience of psychologists collaborating across specialties – clinical, experimental, social, and applied – enriched the field’s knowledge base and shaped the multidisciplinary nature of I/O psychology as it exists today.

From wartime necessity to modern workplace science 🔗

The story of I/O psychology’s early development is really a story about what happens when urgent practical problems meet scientific thinking. The World Wars created conditions that demanded rapid, large-scale solutions to human resource challenges – and psychologists stepped up.

Yerkes showed that psychological assessment could operate at a scale previously unimaginable. Bingham proved that academic research could directly solve practical organizational problems. Cattell built the institutional infrastructure that allowed psychological science to serve industry on an ongoing basis. Together, their contributions turned I/O psychology from a small academic niche into a field with global impact.

The tools have certainly evolved – we’ve moved from paper-and-pencil tests in military camps to computerized adaptive testing and AI-driven assessments. But the fundamental idea remains the same: that understanding human psychology is essential to building effective organizations. Every modern hiring assessment, personality inventory, or leadership development program can trace its lineage back to those psychologists who first proved the value of their science under the pressure of war.

What do you think? How have the assessment tools developed during wartime continued to shape the way modern organizations select and manage talent? And do you think the shift from subjective judgment to standardized testing has been entirely beneficial, or has something been lost along the way?

References

1. https://behavioralscientist.org/psychologists-go-war/
2. https://www.oxfordreference.com/display/10.1093/oi/authority.20110803095424949
3. https://historyofpsychologicaltesting.wordpress.com/intellectual-assessment/wwi-beyond/
4. https://pmc.ncbi.nlm.nih.gov/articles/PMC6526409/
5. https://psychology.iresearchnet.com/industrial-organizational-psychology/i-o-psychology-history/i-o-psychology-in-north-america/
6. https://pressbooks.pub/workplacepsychology/chapter/psy104_ch01/
7. https://www.britannica.com/biography/James-McKeen-Cattell
8. https://www.psychologicalscience.org/members/awards-and-honors/cattell-fund/history
9. https://www.officialasvab.com/recruiters/history-of-military-testing/