Share EF EPI

ABOUT EPI SIXTH EDITION

Methodology

The EF English Proficiency Index is increasingly cited as an authoritative data source by journalists, educators, elected officials, and business leaders. EF is pleased to contribute to the ongoing global conversation about English language education.

In order to use the EF EPI effectively, readers must understand its methodology. The EF EPI is constructed each year from the results of a set of English tests completed by hundreds of thousands of adults around the world during the previous calendar year. The data for this sixth edition was calculated using results from 950,000 test takers who completed three different EF English tests in 2015.

The Tests

Two tests 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. All three tests include reading and listening sections.

The open online tests are 30-question adaptive exams, meaning that each test taker’s questions are adjusted in difficulty according to his or her previous correct and incorrect answers. An analysis was conducted of 47,600 test takers who completed multiple versions of the adaptive exams to establish a uniform and consistent method for scoring across them. The non-adaptive placement test is 70 questions in length. All scores have been validated against EF’s course levels. The test administration is identical for all tests, with test takers completing the exam on computers.

Test Takers

Although the sample of test takers for the EF English Proficiency Index is biased towards respondents who are interested in pursuing language study, the sample is balanced between male and female respondents and represents adult language learners from a broad range of ages. Female respondents comprised 46.3% of the overall sample, and the median age of adult respondents was 28 years. 98.9% of adult respondents were under the age of 60. Male respondents tended to be slightly older, with a median age two years higher than that of female respondents. Because respondents are motivated to take the test by their interest in learning English, the sample should consist primarily of working-aged adults, with a bias towards students and people at the beginning of their careers.

Only countries with a minimum of 400 test takers were included in the index, but in most cases the number of test takers was far greater. A total of 72 countries and territories were included.

We recognize that the test-taking population represented in this index is self-selected and not guaranteed to be representative of the country as a whole. Only those 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. There is no incentive for test takers to inflate their scores artificially on these low-stakes tests by cheating or cramming, as the results do not lead to certification or admission to a program.

These tests are free and online, so anyone with an Internet connection can participate. Almost all of our test takers are working adults or young adults finishing their studies. People without Internet access are excluded. In countries 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, less educated, and less privileged people. Nevertheless, the open-access methods of Internet tests have proven effective in gathering very large amounts of data about evolving English proficiency levels in the global workforce.

Score Caluculation

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 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 within each region.

Each country has been assigned to a proficiency band based on its score. These proficiency bands allow recognition of groups of countries with similar English skill levels and comparisons within and between regions. The proficiency bands are aligned to the Common European Framework of Reference (CEFR) and EF’s course levels. The Very High Proficiency band corresponds to CEFR level B2. High, Moderate, and Low Proficiency bands correspond to CEFR level B1, with each band corresponding to a single EF course level. The Very Low Proficiency band corresponds to CEFR level A2. See pages 9 and 40 for more details about the specific abilities of English speakers in each band.

Other Data Sources

The EF EPI is created through an entirely different process from the one used by public opinion research organizations such as Euromonitor and Gallup, or by the OECD in skills surveys such as PISA and PIAAC. In order to compose a survey panel, those studies select survey participants using age, gender, level of education, income, and other factors. Their survey panels tend to be small, with at most a few thousand participants per country, but because they have been composed using complex sampling methods, they are considered representative of the entire population.

Another source of data about English proficiency comes from national education systems. Many countries test the English skills of every high school student using a standardized national assessment. The results of that exam may or may not be made public, but educators and government officials use the data to assess the efficacy of education reform and pinpoint areas for improvement.

Unfortunately, those national assessments are not comparable to each other, and they are not administered to adults, so although they give a good indication of English proficiency among high school students in a single country over time, they cannot be used to compare students between countries, nor can they tell us anything about adult English proficiency levels.

The EF EPI does not aim to compete with or contradict national test results, language polling data, or any other data set. Instead, these data sets complement each other. Some are granular, but limited in scope to a single age group, country, or test taker profile. The EF EPI is broad, examining working-aged adults around the world using a common assessment method. There is no other data set of comparable size and scope, and despite its limitations, we, and many others, believe it to be a valuable reference point in the global conversation about English language education.

Related EF EPI Reports

The EF EPI research series has three separate reports: this main EF EPI report, which looks at adult English proficiency; the EF EPI for Companies (EF EPI-c), which examines workforce English; and the EF EPI for Schools (EF EPI-s), which tests secondary school and university students around the world. This year, we are publishing the EF EPI sixth edition and the EF EPI-c third edition. The EF EPI-s first edition was published in 2015.

EF Education First

EF Education First (www.ef.com) is an international education company that focuses on language, academics, and cultural experience. Founded in 1965, EF's mission is "opening the world through education." With 500 schools and offices in more than 50 countries, EF is the Official Language Training Supplier of the Rio 2016 Summer Olympics. The EF English Proficiency Index is published by EF Learning Labs, the research and innovation division of EF Education First.

More EF EPI Reports

EF EPI-s

EF English Proficiency Index for Schools

The EF English Proficiency Index for Schools (EF EPI-s) is a study of the acquisition of English skills by secondary and tertiary students.

NEW EF EPI-c 2016 REPORT

EF EPI-c

EF English Proficiency Index for Companies

The EF English Proficiency Index for Companies (EF EPI-c) is an evaluation of global workforce English skills.

Participate in the EF EPI

EF Standard English Test

Participate in the next EF EPI report by taking the EF SET – the world's first free standardized English test.