The latest study has found that one extra year of schooling may leave students with new knowledge and may lead to a small but noticeable increase in students’ IQ.
The researchers found that an additional year of education was associated with an increase in IQ that ranged from 1.197 IQ points to 5.229 IQ points.
In combination, the studies indicated that an additional year of education correlated with an average increase of 3.394 IQ points.
Research has long shown that years of education and intelligence are correlated but it has been unclear whether this is because education boosts intelligence or because individuals who start off with higher IQ scores are likely to stay in school for longer, the researchers said.
For the study, published in the journal Psychological Science, researchers looked at three particular types of quasi-experimental studies from a variety of sources, including published articles, books, preprint articles, working papers, dissertations, and theses.
To be included in the meta-analysis, each data set had to provide cognitive scores obtained from objective measurement with participants who were six or older and cognitively healthy.
This yielded 42 datasets from 28 studies collected from a total of 615,812 individuals, the researchers said.
The researchers also noted that each type of study has strengths and weaknesses, and the findings raise several new questions that future research will have to address.