By Nick Clark, Editor World Education News & Reviews
The mobility of students and academics across borders has become big business in recent years, and authorities in receiving countries have become increasingly efficient in tracking and reporting the data surrounding their education-export industries. Yet, the comparison of international enrollment statistics is somewhat problematic as national agencies collect data in different ways and according to different definitions. This makes statistical comparisons difficult and often inaccurate or misleading.
In recognition of this, the two biggest compilers and aggregators of cross-border student mobility data have, since 2006, attempted to standardize terms and definitions related to the collection of academic mobility statistics. Specifically, they have drawn a distinction between an international student and a foreign student, in a bid to encourage national agencies to standardize their data along similar lines.
International Students Versus Foreign Students
According to the UNESCO Institute for Statistics ’ (UIS) Global Education Digest  (2006), an internationally mobile student has left his or her country, or territory of origin, and moved to another country or territory with the singular objective of studying. The OECD, in its Education at a Glance  (2006) report supports this definition and makes an important distinction between “international students” and “foreign students” in defining terms for the cross-border-mobility section of its comparative dataset.
Adopted in 2006, the OECD and UIS convention is to use the term “international student” when referring to students crossing borders for the specific purpose of studying and the term “foreign student” for non-citizens enrolled at an institution of education outside their home country, but who have not necessarily crossed a border to study (therefore not strictly mobile, and cause for an over-count of actual mobility figures).
While the UIS and OECD accept and tabulate data from counties that count international students based on citizenship (foreign students) for their annual comparative education reports, they have made clear since 2006 (in collaboration with Eurostat ) that international students are defined according to the following characteristics:
- Permanent Residence: Students are considered internationally mobile if they are not permanent residents of the host country in which they pursue their studies.
- Prior Education: Students are considered internationally mobile if they obtained the entry qualification to their current level of study in another country.
Citizenship, or lack thereof, is commonly used as a defining characteristic of an internationally mobile student, especially for data from European Union and OECD countries. However, it is considered an inadequate definition by the UIS, which adds a second criterion, prior education or permanent residence, to qualify citizenship.
In countries where naturalization is less common, as in many European countries, the foreign student count (citizenship), as defined by the OECD, would likely be much higher than the international student count because many immigrants or permanent residents without citizenship of their country of residence would be counted as foreign students, even if they have been in the country much or all of their life. The prior education criterion would eliminate these students from the count. In countries such as the United States and Canada, where naturalization is more common, the foreign student count would likely be closer to the international student count. Put another way, a permanent resident who has already been in country for a period of time would be considered a foreign student and included in the totals of countries collecting data based on citizenship, but not counted by countries basing data on visa issuances. This, as the OECD points out, “results in an overestimate of numbers of foreign students in countries with comparatively low rates of naturalization of their immigrant populations.”1 
At this moment, however, the UIS and OECD recognize that countries use different criteria to measure the number of foreign or international students studying in their countries. As such, they point out that the statistics represented in their annual reports may not be entirely comparable and should be compared only after careful consideration of what and how each country counts.
Total Global Counts Include Citizenship Data
The UIS reported in 2009 that in 2007, from a count of 153 host countries compiling and reporting such data, “over 2.8 million students were enrolled in educational institutions outside their country of origin.”2  The OECD reported in 2008 that in 2006, “over 2.9 million tertiary students were enrolled outside their country of citizenship,” 3  representing a 3 percent increase from the previous year in total cross-border student intake reported to the OECD. It is important to note that as defined, these numbers are tallies of both foreign and international students, although it might be argued that “country of origin” is a different distinction from “country of citizenship.” This fact might account for the different totals, although this is not specifically addressed in either report.
Considering the two organizations share statistical datasets, it is no great surprise that they come up with a similar number, but also something of a surprise that the numbers are not the same. The different results reported by the OECD and UIS are likely due to slight differences in the number of countries that report, although unlike the UIS the OECD does not indicate in its report exactly how many countries reported for its study. It does however state that “data on total foreign enrollments worldwide are based on the number of foreign students enrolled in countries reporting data to the OECD and to the UNESCO Institute for Statistics and thus may be underestimated.” Therefore, the likelihood is that the OECD receives data from a slightly larger number of countries.
Changing the Definition of an International Student Results in a 32% Increase in Enrollments
As an example of the difference a definition can make, the United Kingdom’s Higher Education Statistics Agency  (HESA) added a new definition to its foreign-student counting methodology this year. As a result, an additional 125,000 ‘foreign students’ (versus ‘international’) were ‘found’ to be studying at British universities than previously estimated (a 32% difference!).
The HESA data, as reported by the British Council  in May, was altered to reflect citizenships rather than residency. Traditionally, HESA has classified students according to the address from which they apply, not the country on their passport, i.e. they have counted international students, not foreign students (as defined by the OECD and UIS). In counting students by domicile of application, HESA found that there were 389,330 international students studying in Britain in the past academic year. However, in counting passports, HESA found that there were 513,570 foreign students at British universities and colleges; a huge difference. The study by the British Council followed a decision to include nationality for the first time in 2007-08 as a compulsory field in data submitted by universities to HESA.
Many of the 124,240 previously non-counted foreign students would likely have made their applications while completing foundation or English language courses in the UK or while studying at British boarding schools. For these students, applications to higher studies would have been made using a UK address, which for statistical purposes makes them equivalent to a domestic applicant.
Soon after this new data was released, a number of media outlets suggested that Britain was now much closer to being on a par with the US  in terms of international recruitment numbers. Indeed the new 513,570 figure is much closer to the 623,805  reported by the New York-based Institute for International Education  (IIE) for academic year 2007/08; however, according to IIE counting methodology an international student is defined thus:
Anyone who is enrolled at an institution of higher education in the United States who is not a U.S. citizen, an immigrant (permanent resident) or a refugee. These may include holders of F (student) visas, J (exchange visitor) visas, and M (vocational training) visas.
The IIE definition is essentially the same therefore as the definition traditionally used by HESA, making a comparison of HESA’s new numbers with IIE’s numbers misleading. The important distinction in the IIE definition is the exclusion of immigrants from the tally.
However, the move to count passports rather than residency or visa issuances brings the UK in line with many other countries in Europe, which count mobile students in a similar manner, to counteract the fact that students can study and move freely within the European Union and are therefore not included on visa counts.
The problem that arises with European data is that as many as 33 percent of ‘foreign students’ in some European countries are long-term or permanent residents, making a measure of true academic mobility on the European continent particularly difficult to accurately gauge.4  With this in mind, the OECD includes in its mobility statistics, data from countries that count “international students … who are not permanent residents of their country of study or, alternatively, those who received their prior education in another country (regardless of citizenship), depending on which operational definition is most appropriate in their national context.”
For non-EU countries, the OECD suggests that the residence criterion usually works well as a count for countries that require a student visa to enter the country for educational purposes. Where countries have not been able to report data on student mobility based on students’ country of origin or prior education the OECD has charted indicators separately to emphasize the need for caution in interpreting comparative student mobility numbers.
In collaboration with UNESCO and Eurostat, the OECD has begun the process of standardizing procedures for measuring international student flows for statistical purposes. However, there remain great differences among national immigration procedures in addition to constraints on the availability of data, which continues to make the accurate comparison of student-flow data complex at best, and misleading and inaccurate at worst.
Therefore the statistical organizations named above continue to rely on the data they are voluntarily provided with by national agencies, and have to offer their comparative student-flow datasets with numerous disclaimers and explanations. While it would be useful if all countries could conform to OECD standards in reporting international students numbers, this is by no means a priority for many countries. Therefore countries still differ in the criteria reported, and there also remains a number of important destination countries (such as China and Egypt) that do not report at all.
Analysts of the OECD and UIS statistics have to continue to be careful in how they cite the data, as much as they would if comparing individual datasets from different countries. The important distinctions and definitions that have been outlined by the agencies are helpful in understanding the subtleties of academic mobility data, and a useful reminder that not all statistics are created equally, despite similar headlines. It is as important to read the fine print of a dataset’s methodology as it is to compare the numbers contained within.
The accompanying article in this edition of WENR looks at the enrollment collecting practices of nationally recognized data-collecting agencies in major host nations in a bid to define what is, and what is not, being counted when headline figures are announced.
4  Kelo, M., Teichler, U., and B. Wachter (2006) Eurodata: Student Mobility in European Higher Education, Bonn, Germany, Lemmens Verlag & Mediengesellschaft.