EF EPI – Frequently asked questions

What is the EF EPI?

The EF English Proficiency Index (EF EPI) is the world’s largest ranking of countries/regions by adult English skills. Published annually, the EF EPI is an important international benchmark for adult English proficiency. The EF EPI reports identify the most common pitfalls and highlight the most effective strategies for improving English proficiency.

What is the methodology behind index?

The EF EPI calculates a country’s/region's average adult English skill level using data from three different versions of the EF SET. Two versions are open to any Internet user for free. The third is an online placement test used by EF during the enrollment process for English courses.

In order to calculate a country’s EF EPI score, each test score was normalized to obtain the percentage of correct answers for that test. All the scores for a country/region were then averaged across the three tests, giving equal weight to each test. Regional and global averages were weighted by the populations of each country/region within each region.

Who are the test takers?

This year’s EF EPI includes adult test takers who are 18 years old and above from 80 countries and regions. The median age of this global sample is 26 years old, and there is an even balance between the genders. More than 90% of the test takers are not EF students.

Are the EF EPI samples representative?

We recognize that the test-taking population represented in this index is self-selected and not guaranteed to be representative of the country/region as a whole. Only those people either wanting to learn English or curious about their English skills will participate in one of these tests. This could skew scores lower or higher than those of the general population.

In addition, because the tests are online, people without Internet access or the ability to complete online applications are automatically excluded. In countries/regions where Internet usage is low, we expect the impact of this exclusion to be the strongest. This sampling bias would tend to pull scores upward by excluding poorer and less educated people.

Why was my country/region not included?

We were only able to include countries/regions with a minimum of 400 test takers. Unfortunately, many of the world’s countries/reginos did not meet this requirement and were not included. We added several countries/regions in this report compared to the previous edition, and we hope to continue expanding the EF EPI’s coverage in order to make our findings on global English levels as comprehensive as possible.

Could I have EF EPI raw data?

We are extremely interested in collaborating and supporting third party research, which we hope the EF EPI can contribute to. If you would like to consider collaboration, please contact us here. However, please note that we have not prepared the source data in such a way that can be shared outside the organization at this time.

What’s the difference between EF EPI, EF EPI-c, and EF EPI-s?

The EF EPI measures adult English proficiency and ranks countries/regions. The EF EPI-c tests professionals, and the EF EPI-s tests high school and university students.

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