PISA assesses 15-year-olds in reading, mathematics and science on a three-year cycle, although the round planned for 2021 was held in 2022 because of the pandemic. For educational administration researchers its main value lies in the school questionnaire, which is completed by principals and covers school management and leadership, autonomy over resources and curriculum, staffing, the learning climate and assessment practices. An optional teacher questionnaire has been available since 2015, but not every system administers it, so coverage needs to be checked country by country.
Türkiye has taken part in every cycle since 2003, including PISA 2025, for which 7,702 students in 203 schools were tested. Since school responses can be linked to student achievement, the data lend themselves to multilevel models of leadership and outcomes, though the design is cross-sectional and does not support causal conclusions. Recent cycles provide ten plausible values per domain and 80 replicate weights, and both must be used. The IEA IDB Analyzer, the R package intsvy and EdSurvey all handle these requirements.