What Is the Average IQ of Doctors? What the Research Actually Shows

Where Does the 123.7 IQ Figure Come From?

The National Longitudinal Survey of Youth 1979 (NLSY79) is a long-running U.S. longitudinal study sponsored by the Bureau of Labor Statistics. It began with 12,686 young men and women born between 1957 and 1964 and followed them through education, employment, family life, and other major stages of adulthood. The NLSY79 contains extensive aptitude and intelligence data. One particularly important source is the Armed Services Vocational Aptitude Battery (ASVAB), which was administered to the NLSY79 cohort in 1980. Official NLSY documentation reports that 11,914 respondents completed the ASVAB. The ASVAB is a battery rather than a conventional IQ test. Its subtests cover different knowledge and cognitive domains, including arithmetic reasoning, mathematics knowledge, word knowledge, paragraph comprehension, coding speed, mechanical comprehension, general science, electronics information, numerical operations, and auto and shop information. NLSY79 documentation also confirms that some respondents had scores from conventional intelligence tests collected through school records, including the Stanford-Binet and Wechsler Intelligence Scale for Children. Those scores were available only for subsets of respondents rather than the entire cohort. That distinction becomes important when discussing the physician estimate. The 123.7 Estimate Xavier Jouve's 2026 reanalysis used NLSY79 AFQT data to estimate cognitive ability across occupations. The analysis used 9,774 NLSY79 respondents with valid AFQT scores and reported a physician/surgeon mean of 123.7 from a group of 30 physicians. The number is therefore traceable to a specific analysis rather than being completely mysterious. But it is still important to describe it accurately: 123.7 is an IQ-equivalent estimate produced from AFQT data, not a mean obtained by giving 30 doctors a standardized clinical IQ test. That difference is the central issue in interpreting the number.

What Does an IQ of 123.7 Mean?

On the commonly used IQ scale with a mean of 100 and standard deviation of 15, a score of 123.7 falls at approximately the 94th percentile. In simple terms, an individual scoring 123.7 on such a scale would score higher than roughly 94 out of 100 people in the relevant norm group. That does not mean that 94% of doctors have an IQ above 123.7. The figure is an occupational mean, not a cutoff or requirement for becoming a physician. If you want to understand how scores translate into percentiles, see IQ Percentile and What Does My IQ Score Mean?.

Is 123.7 Actually an IQ Score?

Not in the same sense as a score obtained from a professionally administered IQ test. This is where many articles about occupational IQ estimates become misleading. A clinical intelligence assessment such as the WAIS uses a standardized test battery and produces scores on an established IQ scale. The WAIS Intelligence Test guide explains how that type of assessment differs from other cognitive and aptitude measures. The NLSY79 physician estimate works differently. AFQT performance was transformed into an IQ-equivalent metric using a statistical conversion. The resulting number can be expressed on an IQ-like scale, but that does not make the underlying assessment identical to a clinical IQ examination. The difference can be summarized this way:

Official NLSY documentation also makes clear that AFQT is derived from selected ASVAB components and that its scoring procedures have changed across versions. For a broader explanation of this distinction, see Aptitude Test vs. IQ Test.

How Reliable Is the 123.7 Estimate?

The 123.7 figure is useful, but it should not be treated as a precise national physician IQ average. The first limitation is sample size. The physician group behind the estimate contains only 30 people. A mean calculated from 30 individuals can be informative, but it is much less stable than an estimate based on a large, representative sample of physicians. The second limitation is measurement. The number comes from an AFQT-based statistical transformation rather than direct administration of a modern clinical intelligence test. The third limitation is interpretation. The NLSY79 was not originally designed as a study of physician intelligence. Researchers later connected respondents' cognitive data with occupational information to examine differences between occupations. That makes 123.7 best understood as a reported occupational IQ-equivalent estimate, not as a definitive answer to the question "What is the true IQ of the average doctor?"

What Does the 2026 Edwards & DeYoung Study Add?

A separate 2026 study by Tobias Edwards and Colin DeYoung provides important evidence, but it should not be confused with a physician IQ study. The researchers analyzed the NLSY79 and NLSY97 cohorts and used ten ASVAB subtests to model general intelligence, or g, along with three specific cognitive abilities: technical ability, speed, and math-verbal ability. The NLSY79 analysis included 11,914 people who had completed the ASVAB. For occupational analysis, the researchers initially had 70 NLSY79 occupation categories. They removed four categories containing five or fewer workers, leaving 66 occupations. Among the 8,667 people with occupation codes, eight were removed because they belonged to rare occupations. The important finding for this article is how doctors were classified. The researchers explain that physicians are part of the broader health diagnosing occupations category. They found that health diagnosing occupations, which include doctors, were among the occupations with high average general intelligence. They also found that doctors specifically were among the occupations with high math-verbal ability. That is strong evidence for a broad conclusion: doctors are represented in an occupational group with high cognitive ability. But it does not establish that the average practicing physician has an IQ of exactly 123.7. Those are different claims. The Edwards & DeYoung study is therefore best described as an occupational cognitive-ability study, not a physician-IQ study.

Occupation Explains Some Cognitive Differences — But Not Everything

The Edwards & DeYoung analysis also found substantial occupational clustering in general intelligence. In the NLSY79 analysis, the multiple correlation between occupation and general intelligence was .49. Squaring that correlation gives approximately 24%, meaning occupational grouping accounted for about 24% of the variance in general intelligence in that analysis. That does not mean that occupation determines 24% of a person's intelligence. It means that people in different occupational groups differed enough in average general cognitive ability that occupation was statistically associated with a meaningful portion of the variation in the sample. Individual variation remains substantial.

Why Are Doctors So High on Cognitive-Ability Measures?

Medicine has a long selection pipeline. Someone who eventually becomes a physician typically has to perform well through several stages of education and professional training. Strong academic performance helps a student enter competitive university programs. Medical school admissions then introduce another selection stage, followed by demanding medical education, licensing examinations, and residency training. The result is a form of cumulative selection: people who remain in the pathway have already passed multiple academic and professional filters. That helps explain why physicians appear near the high end of occupational cognitive-ability distributions. But it would be too simplistic to say that IQ alone creates a successful physician. Medical practice also depends on knowledge, clinical reasoning, communication, judgment, experience, professionalism, teamwork, and the ability to make decisions under uncertainty. See Does IQ Predict Success? for a broader discussion of the relationship between cognitive ability and real-world outcomes.

What About the MCAT?

The MCAT is another reason to be careful when discussing cognitive ability and medicine. The MCAT is an admissions examination rather than an IQ test. It is used by medical and MD-PhD programs as one component of evaluating applicants. A Vanderbilt study published in Advances in Health Sciences Education examined 153 graduates of the university's Medical Scientist Training Program who matriculated between 1963 and 2003. The researchers found that MCAT scores were generally inconsistent or weak predictors of many later training and career outcomes within that MD-PhD population. This does not mean the MCAT is useless or that cognitive ability has no relevance to medical training. Instead, it illustrates an important statistical point: once people have already passed a highly selective educational threshold, a single admissions measure may become less useful for distinguishing their later performance. That is another reason not to turn physician IQ discussions into a simple equation such as "higher IQ = better doctor."

Why Does the "125 IQ" Figure Keep Appearing?

The number 125 appears frequently in articles and search results about physician intelligence. The problem is not that 125 is an impossible IQ. It is a perfectly plausible score on a conventional IQ scale. The problem is that the specific claim "the average doctor has an IQ of 125" is often presented without the information that would allow readers to evaluate it: no clearly identified study, sample, methodology, or original calculation. The existence of the 123.7 NLSY79-derived estimate provides a possible reason that a rounded number such as 125 became popular. But that connection should not be presented as established fact. The safer conclusion is simple: 123.7 has a traceable methodological origin; 125 is widely repeated but does not have an equally clear research basis.

123.7 vs. 125: What Does the Evidence Support?

What Occupational Averages Cannot Tell You

An occupational average describes a population, not an individual. A physician can score substantially above or below an occupational mean. Likewise, people outside medicine can have cognitive scores higher than those of individual physicians. This is an important point whenever occupational IQ statistics are discussed. A mean does not create a minimum requirement for entering a profession, and it does not tell us whether a particular person is intelligent, competent, empathetic, or effective at their job. The same principle applies to every occupation. An occupational cognitive-ability estimate can tell us something about group-level patterns. It cannot be used as an intelligence test for an individual doctor.

Does a High IQ Make Someone a Better Doctor?

Not necessarily. Cognitive ability can be relevant to learning complex information, reasoning through unfamiliar problems, and handling demanding academic material. Those abilities are clearly useful in medicine. But being an effective physician involves much more than abstract cognitive ability. Clinical judgment, communication, professional behavior, experience, teamwork, patient interaction, and decision-making under uncertainty all matter. A person can have a high IQ and still be a poor physician, just as someone with a more ordinary cognitive score can become an excellent doctor. The evidence therefore supports a relationship between cognitive ability and occupational selection, not a simple formula linking IQ to medical competence.

Final Verdict

So, what is the average IQ of doctors? The most defensible numerical answer is 123.7 as a reported IQ-equivalent occupational estimate, not 125. The figure can be traced to a 2026 reanalysis of NLSY79 AFQT data and was calculated from a small group of 30 physicians. That makes 123.7 considerably more informative than an unexplained "125" claim, but it still should not be presented as the scientifically established IQ of the average doctor. The newer Edwards & DeYoung research provides a different and arguably stronger conclusion. Doctors were included in the broader health diagnosing occupations category, which the study found to have high average general cognitive ability, and doctors specifically showed high math-verbal ability. The safest overall conclusion is therefore: doctors, as an occupational group, appear to have relatively high cognitive ability, but there is no scientifically established single IQ number that represents every doctor. The 123.7 figure is a useful estimate with important limitations, while the popular 125 figure should not be presented as an established research finding. For readers who want to understand the underlying concepts, see Psychometrics, How IQ Tests Work, and Stanford-Binet Test.

Sources & References

• 1. Xavier Jouve (2026) Jouve, X. — "Cognitive Ability Across Occupations: A Reanalysis of the NLSY79 Armed Forces Qualification Test Data." Cogn-IQ Research Papers. View the Jouve NLSY79 occupational analysis
• Edwards, T., & DeYoung, C. G. — "More Than General Intelligence: Cognitive Abilities and Class Structure." Intelligence & Cognitive Abilities. DOI: 10.65550/001c.162975. Read the Edwards & DeYoung stud
• 3. U.S. Bureau of Labor Statistics — NLSY79 National Longitudinal Survey of Youth 1979 (NLSY79) Data Overview. The official BLS documentation confirms the original 12,686-person cohort, its birth-year range, sampling structure, and longitudinal design. View the official NLSY79 Data Overview
• 4. National Longitudinal Surveys — Aptitude, Achievement & Intelligence Scores The official NLSY documentation describes the ASVAB administration, AFQT scoring, the 11,914 NLSY79 ASVAB participants, and the additional intelligence-test information available from school records. View the official NLSY79 cognitive and aptitude documentation
• 5. Bills et al. (2016) — MCAT Predictive Validity Bills, J. L., VanHouten, J., Grundy, M. M., Chalkley, R., & Dermody, T. S. — "Validity of the Medical College Admission Test for predicting MD-PhD student outcomes." Advances in Health Sciences Education, 21, 33–49. DOI: 10.1007/s10459-015-9609-x. View the study on PubMed View the full-text study on PMC