>>212262920 (OP)regardless what you think of iq,
reminder that the "references" used for lebanon are an n=300 study that tests:
- 100 WORKING (i.e extremely poor) children exposed to some sort of neurotoxic solvent
- 100 WORKING children
- 100 non-working children
all in TRIPOLI (very poor city, generally speaking)
additionally, they all likely went to public school, which just like public electricity, is quite terrible.
PISA and TIMSS testing was also done on children educated in public schools. everyone who can afford it (it's not that expensive) puts their children in private schools.
https://www.ulsterinstitute.org/ebook/THE%20INTELLIGENCE%20OF%20NATIONS%20-%20Richard%20Lynn,%20David%20Becker.pdf
https://www.researchgate.net/publication/6407995_Evidence_of_Neurotoxicity_in_Working_Children_in_Lebanon