Changes in percentages of students at Level 2 or above across ICILS cycles

Standard error appear in parentheses (). Because of rounding some results may appear inconsistent. Statistically significant differences between cycles are marked in Bold.

† Met guidelines for sampling participation rates only after replacement schools were included.

‡ Does not meet guideline for sampling participation rate, but achieved at least 50% overall sampling participation rate.

1 National defined population covers 90% to 95% of the national target population. See Appendix A for further information.

2 Country surveyed target grade in the first half of the school year.

3 National defined population covers 61% of the national target population.

b Country met guidelines for sampling participation rates only after replacement schools were included in the indicated cycle.

c Country nearly met guidelines for sampling participation rates after replacement schools were included in 2018.

d National defined population covered 90% to 95% of national target population in 2018.

e Country surveyed target grade in the first half of the school year in 2018.