PISA 2015 Data

Data analysis

All statistics were computed using sampling weights; standard errors based on balanced repeated replication weights were used for statistical significance and/or confidence intervals.

Analyses based on achievement test results (plausible values) were based on Rubin’s rule for multiply imputed variables.

The OECD average corresponded to the arithmetic mean of the respective country estimates.

Secondary analysis

The PISA data analysis manual provides SAS and SPSS codes for analyzing PISA microdata.

User-written software is also available in Stata (repest, pisatools) and R (intsvy).

Basic statistics can be computed with the PISA Data Explorer.

Types of data files
  • Student questionnaire data file (includes responses to the parent questionnaire and optional student questionnaire, as well as plausible values for test achievement)
  • School questionnaire data file
  • Cognitive item response data file
  • Scored cognitive response data file
  • Teacher questionnaire data file
  • Student questionnaire timing information data file (includes information about the time spent answering each questionnaire screen).
Format(s) of data files
Item release policy

Most items are kept confidential for re-use in future cycles in order to measure trends. A minority of items are released after each cycle to illustrate new frameworks and provide samples of tasks at different levels of proficiency.