The OECD has thrown out Catalonia’s PISA results after finding that almost 25% of selected students were excluded from the test, far above the allowed limit. The error removed Catalonia from the international education rankings and exposed a breakdown in the region’s system for evaluating schools.
The basic problem was a lack of leadership. The Council Superior de Evaluación, which managed PISA and other assessments, was already struggling when the tests were organized. Its last president, Carlos Vega, was dismissed in January 2024 after earlier PISA problems. For more than a year, interim leaders ran the Council, while the director general of Currículo handled several jobs at once.
Information from ElDiario and ARA, only 1,909 of approximately 2,500 selected students in Catalonia took part in the PISA assessment. A total of 591 were excluded, far exceeding the OECD’s 5% exclusion limit.
During this period, the Catalan government tried to replace the Council with a new Agency of Evaluation. The agency officially launched in April 2025, in the middle of PISA testing, but lacked full staffing and a working structure. Its new director, Núria Planas, later said the agency was not really functional until July and was still hiring technical staff at that point.
Meanwhile, many experienced Council staff either left or were replaced, with no proper handover. The organization lost the knowledge and continuity needed to run PISA smoothly. One former member described the Council as "decapitated." In the resulting power vacuum, serious mistakes went unnoticed.
The effects were immediate. Schools received incomplete instructions and were not told about the strict rule limiting exclusions to no more than 5% of the sample. Instead, 23% were left out, often because of language barriers or learning difficulties. The Council ignored repeated warnings from PISA organizers, and Spain’s Ministry of Education caught the mistake only after the data had been sent.
ARA reports that the National Institute for Educational Evaluation (INEE) warned Catalan authorities up to seven times about sampling issues. Several alerts came as early as April 2025, when corrective action was still possible. An internal inquiry found no evidence that the warnings were effectively communicated to schools.
Adding to the confusion, two senior officials, the director general and the secretary of Mejora Educativa, were dismissed in October 2025, just months after the PISA incident. Both had also faced criticism over a controversial curriculum reform that merged several science subjects, a move opposed by teachers. During this unstable period, schools were running other regional and national assessments, but only PISA had strict exclusion rules.
Some officials have tried to downplay the PISA error, but insiders say other assessments also suffered from poor planning. For example, oral language tests were supposed to be conducted remotely by outside evaluators, but the plan was dropped after teachers complained. Without clear leadership or technical support, many schools were left confused and on their own.
After the Ministry of Education declared Catalonia’s PISA results invalid in March 2026, an internal investigation began. Three disciplinary cases were opened against two former Council technicians and a former senior official. On the same day, the department’s number two, Teresa Sambola, was dismissed, though the education minister denied any direct link to the PISA case.
Experts in educational assessment have said they are shocked by the scale of the exclusions. Francesc Pedró, a former OECD analyst, said he had never seen such a high exclusion rate. Joan Mateo, who led the Council from 2009 to 2021, argued that responsibility does not rest with just a few technicians, especially since senior officials missed the error. The lack of transparency and accountability has deepened the sense of institutional failure.
Catalonia’s expanded PISA sample, which the region pays for to obtain detailed data from many schools, will not be analyzed or reported by the OECD. Only the raw data will be published for use in Spain’s national average. The new Agency of Evaluation has said it will not produce its usual detailed report, leaving analysts with little more than unprocessed numbers.
This is not the only recent case of bureaucratic failure in Spain’s public sector. As reported earlier, similar problems with oversight and transition have caused serious issues in other regions and sectors. The Catalan education crisis shows how quickly established systems can falter when experienced staff are lost and leadership is missing. The government’s attempt to modernize its evaluation process has exposed how fragile reforms can be without continuity or expertise, while accountability remains elusive.
