The OECD became aware of the high exemption rate of students in Catalonia in the PISA tests in March 2026, when it received the relevant reports from Spain and its autonomous communities, and immediately reported the issue to the Ministry of Education and Vocational Training, according to a spokesperson for the organization who spoke to La Vanguardia. The tests were conducted in April 2025 and at that time technicians from the Ministry and the Generalitat already warned of the high rate of students exempted from taking the exams, but, according to the ministry, they did not escalate it to their superiors, so there was no room for correction nor, supposedly, the capacity to inform the OECD evaluation group.
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The evaluation was based, the spokesperson who responds to this newspaper’s questions by email indicates, “exclusively on the exceptionally high exclusion rate,” as well as on the unprecedented increase compared to PISA 2022.
“Exemption rates of 10% in PISA are rare and Catalonia’s was 23%”
The OECD did not receive a complete report on this nor has it opened its own investigation because Catalonia is not an “entity subject to the PISA adjudication process” as Spain is, which appears in the international ranking. In that case, the data are independently reviewed and cross-checked by the PISA adjudication group, the contracted international companies, and the OECD to verify if they meet PISA’s technical standards and if their results can be published and compared internationally.
Therefore, when the intergovernmental organization that advises governments on public policy design saw that more than five hundred students out of the 2,500 selected (23.2% of the total) had been left out of the test, they decided two things: to remove Catalonia from the annex of the international report and include its data “for transparency” in the national report, adding that they are not valid for comparisons.
“The national report of Spain offers the possibility to present more complete information on subnational results and to explain in greater detail their context, limitations, and implications. This allows readers to better understand why Catalonia’s results are not considered suitable for international comparisons or for temporal (trend) comparisons, while maintaining transparency about the data collected,” adds the spokesperson.
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The OECD has not opened its own investigation because Catalonia is not an entity in the international ranking
However, they demand that the administration thoroughly investigate the causes of this high exclusion rate. “Catalonia must investigate the factors that contributed to the high exclusion rate in 2025 and take appropriate measures to reduce these exclusions in future PISA cycles.”
The “exceptionally high” exclusion rate is unprecedented in PISA’s history. In 25 years it has not happened in any countries or regions. In previous editions, the 5% limit established by PISA’s technical standards has been exceeded, with percentages ranging between 6% and 12%. “However, exclusion rates above 20% have never been observed.”
In Denmark, a rate of 11.6% was reached by excluding children with dyslexia who could not use support devices
For example, in PISA 2022, Canada (5.8%), the United States (6.1%), the Netherlands (8.4%), and the highest, Denmark, with 11.6%, exceeded the exclusion threshold. In Denmark’s case in PISA 2022, the report explicitly explained that the increase in exclusions was mainly due to the rise in students diagnosed with dyslexia and that these students used electronic support devices for reading during the exams. Since PISA did not allow these supports, many centers decided to exclude those students. “The OECD added that, to reduce these exclusions in future editions, PISA could better adapt the test for students with dyslexia,” the spokesperson points out.