The Chinese mainland’s chart-topping scores in a recent high-profile global education study have sparked both pride and no small amount of controversy.

The best and brightest 15-year-olds from four key localities surpassed their overseas peers by ranking No. 1 for ability in the three core subjects of reading, math, and science in the 2018 Program International Student Assessment (PISA), the results of which were announced Tuesday.

The news marked a return to form for a country that languished in 10th place in the results of the 2015 test. PISA, which is coordinated by the Organization for Economic Cooperation and Development (OECD), is held every three years.

But familiar criticisms of the assessment swiftly followed, with some commentators pointing out that the mainland Chinese participants, who were drawn from the wealthy megacities of Beijing and Shanghai as well as the developed eastern provinces of Jiangsu and Zhejiang, are not representative of the true quality of China’s education system.

Others questioned the validity of the data, noting that mainland China’s 2018 scores are significantly higher than 2015, when the southern province of Guangdong was included instead of Zhejiang. The OECD allows China to approve which areas of the country can be subjected to testing.

Read the full story on Caixin Global later today.

Contact reporter Matthew Walsh (matthewwalsh@caixin.com)

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