Intelligence quotient (IQ) of Thai students in the first year of primary school: national survey 2016

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Janarpar Sookatup
Amporn Benjapolpitak
Vanida Chaninyuthwong
Prasert Chutha


          Objective To study the average intelligence quotient and intelligence quotient distribution among Thai students in the fi rst year of primary school in 2016.
          Material and methods The survey was assessing representative samples of the fi rst year of primary school Thai students from every provinces and every kind of school affi liation in Thailand except for those affi liated with the Department of Social Development and Welfare. The 23,641 sampling was derived from a stratifi ed cluster sampling model. The data collected from November 2015 to January 2016 by psychologists in each province using the Standard Progressive Matrices and analyzed with descriptive statistics. The estimation of weighted prevalence was also performed.
          Results The average IQ of the fi rst-year primary school Thai students was 98.2. When analyzed by province. The average IQ was found to be higher than 100 in 12 provinces (15.6%), approximately 100 in 30 provinces (39.0%) and lower than 100 in 35 provinces (45.4%). Considering the national IQ distribution according to Wechsler’s IQ classifi cation, it was found that 31.8% of the students has lower IQ than normal (IQ<90), and 5.8% of the students with intellectual disability (IQ<70). On the other hand, it was found that the percentage of students with very superior IQ level (IQ≥130) were as high as 7.9%.
          Conclusion The average IQ of the fi rst-year primary school Thai students in 2016 was average and close to the international standards (IQ=100). However, the percentage of Thai students with low IQ is higher than the international standard.


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