Laos is the least populated country in Indochina; home to nearly 7 million people. It is a single-party Marxist state, and ranks close to Cambodia and Burma on the tail end of human development indices. Ethnic Lao are about 55% of the population and inhabit the lowland regions. Numerous ethnic minorities inhabit more elevated regions, including the Hmong, who are about 8% of the population.

In this post I review one small study with intelligence test data for the nation of Laos. I also summarize over a dozen studies with intelligence and achievement test scores for Laotians living in the United States. A majority of these studies are for Hmong Americans.

⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻ HᏤ ⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻

Boivin et al (1996 ) tested two groups of children in Laos with the Kaufman Assessment Battery for Children (K-ABC). The first sample was mostly drawn from higher socioeconomic status families in the capital city of Vientiane. The second sample was drawn from rural schools outside of the capital. The K-ABC was translated into Lao and administered by trained physicians.

The IQ of 24 urban children was 112.7 while the IQ of 22 rural children was 89.9.

The mothers of these children were also tested with the Matrix Analogies Test-Expanded Form (an intelligence test that closely resembles Raven’s Progressive Matrices). The IQ of 24 urban mothers was 108.7, and the IQ of 22 rural mothers was 91.3.

The urban sample was described as “mainly children of medical staff … and administrative professionals” at a University affiliated hospital. So this is a slightly advantaged sample. The rural children were described in average terms: “… not from families in abject poverty but… less affluent than those of the professional class in Vientiane” (p. 590).

The average of the two normal samples is 90.6, which is also our national IQ estimate for Laos.

This is close to the estimate that Lynn & Vanhanen (2006; 2012) make from the same study: 89. Lynn cites data for two samples, and is also apparently using the IQ values from the rural mothers and their children, but he misreports the data as coming from two samples of 8 year-olds that were tested with the K-ABC, instead of one sample of 8 year-olds that was tested with the K-ABC and one adult sample that was tested with the MxAT. This is a confusing error since two samples of 8 year-olds were tested with the K-ABC (the average IQ of the two 8 year-old samples is 101.8 and not 89).

Table I: IQ test scores in Laos

Admin Sample Age N Test IQ Reference
~1995 SA 5-12 24 KABC 113 Boivin et al, 1996
~1995 A 5-12 22 KABC 90 Boivin et al, 1996
~1995 SA Adult 24 MxAT 109 Boivin et al, 1996
~1995 A Adult 22 MxAT 91 Boivin et al, 1996


The northeast of Thailand—called Isan—shares a long border with Laos along the Mekong river, and the people in this region speak a dialect of Lao and are close ethnic cousins to the majority people of Laos. The Northeast has an estimated IQ of 90, and is the lowest performing region in Thailand. This similarity suggests that 90.6 is a decent estimate for Laos. The scores for Laotian immigrant groups reviewed in the next section are also very similar.


Intelligence and Achievement Test Scores of Laotian Americans

Two culturally distinct groups from Laos fled to America after the Communists took power in 1975: Lao and Hmong.

■ Lao Americans

Two unpublished student dissertations from the 1980s contain intelligence test scores from newly arrived Lao refugees.

IQ data was collected for 6-13 year-old immigrants in North Texas (Utairatanakit, 1987 ). These children were all born in Laos and had been in the US between 1-6 years. They were given the K-ABC as well as the performance scale of the Wechsler Intelligence Scale for Children-Revised. The test examiners were fluent in Lao, and the test instructions were given in both Lao and English.

Their IQ on the WISC was 102.4 and their IQ on the K-ABC was 100.4. So the average IQ of this sample was 101.4.

There is also IQ data for a group of Lao immigrant children in Nashville, Tennessee (Nasseh, 1988 ). These were 4th graders in English as a Second Language (ESL) programs. They had been in the country, on average, for 4 years. This sample had a Raven’s Progressive Matrices IQ of 76.1

There is a large difference between these two studies, but the average gives us an IQ of 88.8 for Lao Americans.

Table II: IQ test scores for Lao Americans

Admin Sample Age N Test IQ Reference
~1986 A 6-13 70 KABC 100 Utairatanakit, 1987
WISC-R 102
~1987 A 10-14 21 CPM 74 Nasseh, 1988
SPM 78


Both of these studies included achievement tests. The Texas sample was given the Iowa Test of Basic Skills and the Nashville sample was given the Stanford Achievement Test. Unfortunately, both report raw scores and I don’t have access to the norms for either test. I will have to update this post at a later date.

Ima & Rumbuat (1987 ) report standard scores for 58 Lao immigrants on the Comprehensive Test of Basic Skills. This group had an Achievement Quotient (AQ) of 92 (Reading=84.1, Math=99.9).

California gives state-wide achievement tests to nearly all school children, and this data is broken down by ethnicity and available online: Standardized Testing and Reporting (STAR).

For the years 2003-2006 I looked at the performance of over 52,000 Lao Americans on the reading and math sections of the California Achievement Test. In comparison with whites, Lao students had an AQ of 90.6 (Reading=88.1, Math=93).

For the years 2009-2012 I looked at the performance of over 36,000 Lao Americans on the math and reading sections of the California Standards Tests. In comparison with whites, Lao students had an AQ of 90.4 (Reading=91.2, Math=89.5).

The median AQ of Lao Americans from three studies is 90.6.

Table III: Achievement scores for Lao Americans

Admin Sample Age N Test AQ Reference
1987 A 12-18 58 CTBS 92 Ima & Rumbaut, 1989
2003-06 A 8-17 52716 CAT 91 Malloy, 2014a
2009-12 A 8-17 36654 CST 90 Malloy, 2014b


■ Hmong Americans

Significant numbers of Hmong live in the highland regions of Thailand, Vietnam, and Laos, but these populations migrated down from southern China only in the last few centuries. A majority of Hmong still live in China.

Their movement into the remote parts of Indochina reflects a cultural history of resisting state control. In the early 20th century the Hmong revolted against colonial French authorities with some success. During the 1960s the United States recruited many Laotian Hmong as mercenaries against the Communist insurgents that were vying for control of Laos. When the Marxists took power they implemented genocidal reprisals that pushed many Hmong into refugee zones in Thailand, where some still live.

Many Laotian Hmong were eventually absorbed by the U.S., which took in hundreds of thousands of Southeast Asian refugees following the Communist victories of the 1970s; over 260,000 Hmong now live in the United States (For scale, some 416,000 still live in Laos).

Hmong Americans are an interesting test case in intergenerational assimilation as they came with almost no beneficial skills for living in a developed economy. A majority of Hmong immigrants were illiterate and had no formal education. In fact, the Hmong didn’t even have a written language before missionaries developed an alphabet in the 1950s.

Most of the studies in this post are specifically for Hmong Americans; this is the first review of Hmong cognitive ability.

Irwin & Madden (1986 ) provide the earliest data for Hmong immigrants. They collected test norms for refugee children attending a summer school program in Appleton, Wisconsin. Performance subtests of the Wechsler Intelligence Scale for Children-Revised were given to 110 children, ages 6-17. Their WISC IQ was 101.9.

The younger children were given the Coloured Progressive Matrices and the older children were given the Standard Progressive Matrices. The CPM IQ was 95.5 and the SPM IQ was 89.4.

The mean IQ from the three tests given to this sample is 95.6.

An older sample of Hmong, ages 20-64 (avg. 37), were also given the Standard Progressive Matrices. Mulder (1991 ) recruited subjects from adult education and ESL courses in Fresno, California. Others were located through religious organizations. The complete sample (N=106) had been in the U.S., on average, for 6 years. 72% had never attended school prior to emigrating.

The test was administered with a Hmong interpreter. Their SPM IQ was 60.6. Raven scores were associated with their adult education grades (.35).

Another study looked at 40 Hmong children in the rural Midwest (Smith et al, 1997 ). The average age was 10 years old and they had lived in the U.S., on average, for 8 years. So this sample was mostly raised in America. They were given the Wechsler Intelligence Scale for Children-III and the Kaufman Brief Intelligence Test.

The WISC IQ of this sample was 81.2. Their K-BIT IQ was 79.8. Performance on the two tests had a correlation of .83. Children from homes that spoke both English and Hmong did not have higher performance than children from households that only used Hmong. However, verbal scores on both the K-BIT and the WISC were over 20 points lower than the performance scores, indicating extensive language deficits. The average IQ of this sample was 80.5, with a verbal IQ of 71.8 and a non-verbal IQ of 93.

One study looked at 56 Hmong children referred for special educational needs in Dunn County, Wisconsin (Preston, 1999 ). Each child was given four different IQ tests: The WISC-III, the K-BIT, the Test of Nonverbal Intelligence-3, and the Comprehensive Test of Nonverbal Intelligence. IQ on the WISC was 79.8, IQ on the K-BIT was 78.5, IQ on the TONI was 102.9, and IQ on the CTONI was 92.4. The average score for the four tests is 88.4.

Since the sampling procedure required a cognitive disadvantage (referral for educational needs), this sample is classified as SD (slightly disadvantaged), and will not be used for the average IQ estimate.

Two student dissertations discuss data from a common sample (Redwine, 2005 ; Wood, 2005 ). This research involves 28 Hmong in La Crosse, WI that were given the Universal Nonverbal Intelligence Test at age 10, and the Comprehensive Test of Nonverbal Intelligence at age 11. Their UNIT IQ was 96.7 and their CTONI IQ was 95.8. Performance on these tests was associated with parental education level (.42)—57.1% of the parents had no education.

Two studies examine the ‘school readiness’ of Hmong (an academic euphemism for preschool IQ). Kan & Kohnert (2008 ) administered the Leiter International Performance Scale-Revised to English- and Hmong-speaking 4 year-olds. The Leiter IQ of these young children was 102.2.

Another study looked at Hmong entering school in St. Paul, Minnesota (Xiaong et al, 2008 ). These are children in Project Early Kindergarten (PEK), an educational experiment in 10 city schools with the intended goal of closing ethnic achievement gaps. About 1/4 of U.S. Hmong live in Minnesota, and St. Paul has the largest urban population of Hmong in the world. Hmong are fully 10% of the St. Paul population, and disproportionately young: over 30% of St. Paul’s public school children are Hmong.

PEK children were given the Peabody Picture Vocabulary Test-III. The Hmong had a PPVT IQ of 68.5.

There is wide variation in the Hmong American IQ scores listed in Table IV: from 60.6 for an uneducated adult sample to 102.2 for a recent sample of preschool children. If we exclude the one study that selected Hmong based on disadvantage (Preston, 1999) we are left with six normal samples of Hmong Americans. The median Hmong IQ from these six samples is 88.

The median nonverbal IQ from five studies is 95.5 and the average verbal IQ from two studies is 70.2. Verbal scores might be excessively low due to test bias, which would mean 95.5 is a more accurate estimate. Adapting a verbal intelligence test, like the PPVT, for the Hmong would help resolve the question of their true verbal abilities.

Table IV: IQ test scores for Hmong Americans

Admin Sample Age N Test IQ Reference
1980 A 6-17 110 WISC 102 Irwin & Madden, 1986
6-11 55 CPM 96
11-17 48 SPM 89
~1990 A 20-64 106 SPM 61 Mulder, 1991
~1996 A 7-13 40 WISC 81 Smith et al, 1997
~1998 SD 6-13 56 WISC 80 Preston, 1999
TONI 103
2001 A 10 28 UNIT 97 Wood, 2005
11 CTONI 96
~2007 A 4 26 Leiter 102 Kan & Kohnert, 2008
2008 A ~6 196 PPVT 69 Xiong et al, 2008


Four studies provide achievement test data. Ima & Rumbuat (1987) give scores for 47 Hmong on the Comprehensive Test of Basic Skills. This group had an AQ of 90.7 (Reading=86.3, Math=99.5).

Madyun & Lee (2010 ) compared a sample of 3185 white and Hmong 7th-8th graders in 79 neighborhoods of St. Paul. All the children took the Metropolitan Achievement Test-7. In comparison with the white children, Hmong had an AQ of 90.5 (Reading=87.7, Math=93.2).

Xiong et al (2008) gave St. Paul kindergarten children three tests from the Woodcock-Johnson Tests of Achievement III. These children had an AQ of 92.9. Despite scoring below the 2nd percentile on the PPVT, this sample did unusually well on the W-J language tests (Reading=97.3, Math=84.2).

Finally, I looked at STAR data from California. Statewide achievement tests only started reporting data for Hmong in 2010. For the years 2010-2012 I looked at the performance of over 28,000 Hmong Americans on the math and reading sections of the California Standards Tests. In comparison with whites, Hmong students had an AQ of 91.3 (Reading=88.9, Math=93.6).

The median Achievement Quotient for Hmong Americans from four studies is 91.

Table IV: Achievement scores for Hmong Americans

Admin Sample Age N Test AQ Reference
1987 A 12-18 47 CTBS 91 Ima & Rumbaut, 1989
2002 A 13-14 ~2337 MAT 91 Madyun & Lee, 2010
2008 A ~6 196 WJTA 93 Xiong et al, 2008
2010-12 A 8-17 28595 CST 91 Malloy, 2014c



In summary, one IQ study from Laos gives a national IQ of 90.6.

Lao speaking people inhabit the neighboring region of northeast Thailand. My estimated IQ for this region was 90.

Two studies of Lao immigrant children in the United States give an IQ of 88.8.

Three studies of Lao Americans give an AQ of 90.6.

There are a larger number of studies for Hmong Americans, a Laotian minority group that started migrating to the United States in the mid-1970s (Hmong are also native to China, Vietnam, and Thailand, but few, if any, Hmong Americans came from these populations).

The median Hmong American IQ from six studies is 88. Their IQ on nonverbal tests was 95.5, and their IQ on verbal tests was 70.2. The low verbal scores could be due to language bias, which would make the nonverbal score a more accurate estimate. I can’t say if this is the case.

The median Hmong American AQ from four studies is 91.

Studies of intelligence and achievement are in agreement that Laotian and Hmong Americans are close to the 25th percentile of white cognitive test performance. This is about 1/3 of a standard deviation higher than African American performance, and close to Hispanic American performance.

The Hmong have higher intelligence and achievement scores than Puerto Rican Americans, another minority with a language handicap. The Hmong have greater difficulties with language tests, but their nonverbal IQ is significantly higher than Puerto Rican nonverbal IQ (95.5 vs. 90.4).

If IQ scores are simply a reflection of developmental exposures to the “Culture of the Test” it is not obvious how freshly arrived refugee children from pre-literate Asian tribes have competitive intelligence test performance with non-Asian U.S. minorities.



⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻ REFERENCES ⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻

Boivin, M.J., Chounramany, C., Giordani, B., Xaisida, S., Choulamountry, L., Pholsena, P., … & Olness, K. (1996). Validating a cognitive ability testing protocol with Lao children for community development applications. Neuropsychology, 10, 588-599.

Ima, K., & Rumbaut, R.G. (1989). Southeast Asian refugees in American schools: A comparison of fluent-English-proficient and limited-English-proficient students. Topics in Language Disorders, 9, 54-75.

Irwin, D.A. & Madden, C. (1986). A psychoeducational assessment procedure for Southeast Asian refugee students. In C.L. Williams & J. Westermeyer (Eds.), Refugee mental health in resettlement countries (pp. 189-204). Washington, D.C., USA: Hemisphere Publishing Corporation.

Kan, P.F., & Kohnert, K. (2008). Fast mapping by bilingual preschool children. Journal of Child Language, 35, 495-514.

Lynn, R., & Vanhanen, T. (2006). IQ & global inequality. Augusta, USA: Washington Summit Publishers.

Lynn, R., & Vanhanen, T. (2012). Intelligence: A Unifying Construct for the Social Sciences. London, UK: Ulster Institute for Social Research.

Madyun, N., & Lee, M. (2010). Neighborhood ethnic density as an explanation for the academic achievement of ethnic minority youth placed in neighborhood disadvantage. Berkeley Review of Education, 1, 87-112.

Mulder, P.L. (1991). An investigation of the effects of level of acculturation on the performance of adult Hmong refugees on Raven’s Standard Progressive Matrices and Bender-Gestalt Visual/Motor Test. Unpublished doctoral dissertation, California School of Professional Psychology, USA.

Nasseh, A.A. (1988). Comparison of intelligence and achievement levels of Laotian and American fourth-grade students in four schools with an ESL/bilingual program. Unpublished doctoral dissertation, George Peabody College for Teachers of Vanderbilt University, USA.

Preston, J. (1999). An investigation of Hmong students’ performance on four standardized cognitive ability measures. Unpublished doctoral dissertation, Graduate College, University of Wisconsin-Stout, USA.

Redwine, D.J. (2005). A comparison of limited English proficient and English proficient Hmong Students’ Performance on the Comprehensive Test of Nonverbal Intelligence. Unpublished educational specialist thesis, University of Wisconsin-La Crosse, USA.

Smith, D.K., Wessels, R.A., & Riebel, E.M. (1997). Use of the WISC-III and K-BIT with Hmong students. Paper presented at Annual Meeting of the American Psychological Association, Chicago, USA, August 1997.

Utairatanakit, D. (1987). Construct and concurrent validity of the Kaufman Assessment Battery for Children (K-ABC) with a Laotian sample. Unpublished doctoral dissertation, Texas Woman’s University, USA.

Wood, R.A. (2005). A Comparison of scores on the Universal Nonverbal Intelligence Test (UNIT) and the Comprehensive Test of Nonverbal Intelligence (CTONI) in a sample of Hmong students. Unpublished education specialist thesis, University of Wisconsin-La Crosse, USA.

Xiong, Z.B., Yang, K.K., & Lee, J.K. (2008). What helps and hinders Hmong pre-kindergartners’ school readiness: learning from and about the Hmong in St. Paul, Minnesota. St. Paul, USA: Ready 4 K.


4 thoughts on “HVGIQ: Laos

  1. The low IQ of the Hmong doesn’t surprise me, although the wide variability is (especially for being in America), which might leave open the possibility that their genotypic IQ is higher than around 90. I don’t think that’s especially likely, especially with the degree of social dysfunction the Hmong exhibit in the US, but I think it does give hope for other southeast asians having higher genotypic IQ’s when a recently illiterate tribal people have IQ’s around what is often given for southeast asian countries by Lynn and co. To that end, I think people in these sorts of discussions very much underrate the historical and cultural record of SE asia- while not much has ever come out of SE asia in terms of unique inventions and discoveries, they certainly do have a strong record of state building and civilization, and in all honesty, I find SE asia’s architectural and artistic record to be much more impressive than much of east asia. The sprawling stone cities and temple complexes you see throughout that region are very elaborate and exhibit a strong degree of engineering expertise, and while one could debate on how much migrations from China and elsewhere have contributed (and how much one can extrapolate the achievements of pre-modern peoples to now) even more isolated islands like Sumatra, Java and Bali developed monumental architecture with advanced, seafaring states.

    Considering how the Hmong are a minority in Laos and Laos’ history of state building goes back quite sometime, it’s very unlikely their genotypic average is that low.

  2. Permit me to add some anecdotal observations to your analysis. I have a 15-year familiarity with the Lao expat community from Eastern New York/Western Connecticut. My wife is half-Lao, half-Thai. My father-in-law is Lao, from the northwest area of Laos, so you could consider him “Hmong” though he doesn’t identify himself as such. He was recruited by U.S. Army Special Forces/CIA as part of the cross-border ops with Vietnam you describe. Biggest reason is he is much taller than the average SE Asian, at 6’0. My mother-in-law is also taller than average for a SE Asian woman at 5’5”. My father-in-law was recruited from the (then) Royal Lao Army and fought in several skirmishes alongside US forces against communist insurgents (both Lao and Vietnamese), and was wounded through the calf. Eventually, he made it to one of the refugee centers in NE Thailand (was able to take advantage of mother-in-law’s Thai citizenship) with his family and emigrated to USA in 1979 to Eastern NY state. He, along with the other Lao expat males I know, was able to find good work in typical blue-collar industries (paper and metal fastening, small machine manufacturing), able to retire with a modest pension 8 years ago. He was able to pick up working English quickly (though he has a pronounced accent). Significantly, my wife grew up in a household where English was not the most frequently spoken language, yet her English is at least as good as mine. She graduated high school in early 1990’s in the top 15% of her class and then graduated from a top NY state private (Catholic) university with a degree in Biology. So, possibly accelerated Flynn effect? Don’t know; my brother-in-law definitely has father’s height gene (he’s also 6’0), but the body of a Pacific Islander (probably because of heavy dairy-based Western diet growing up in USA) who played O-line on high school football team, and spent two tours in the Middle East (martial skill is highly prized in the Lao/Hmong expat community). Not sure how much/well this informs your statistical aggregation/analysis, but can give you a flavor of the range in cognitive skills within and between generations of the population you are referencing.

  3. Thanks.

    It’s been 39 years since 1975 (wow … I feel old) so there are no doubt by now schoolchildren of Laotian / Hmong background whose parents were also born in America. It will be interesting to see how they do.

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