Since 2000, the PISA test implemented by OECD has become the prime benchmark for international comparisons in education. The 2015 PISA edition introduced methodological changes that altered the nature of its results. PISA made no longer valid non-reached items of the final part of the test, assuming that those unanswered questions were more a…

The original data strategy on which PISA was based suggested that, after the completion of the first three assessments in 2000, 2003 and 2006, the cycle would repeat itself with three-yearly assessments in the areas of reading, mathematics and science. However, in light of newly emerging policy priorities and the experience gained with PISA so…