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RESEARCH COMPARES THE TOEFL iBT WITH IELTS
The IELTS Academic as well as the TOEFL iBT both measure a candidates English capabilities in the four fields of reading, writing, listening and speaking.
It is not uncommon for researchers to attempt to draw some correlation between tests for the purpose of comparison. In the United States, for example, the results of two major college entry examinations, the SAT and ACT were linked, so that the universities could use one or the other to evaluate students seeking admission.
The research
ETS wanted to compare the results of the TOEFL and the IELTS to see whether they could be used interchangeably. In line with best practice they first ran a preliminary research study to interrogate which sections of the two tests were comparable and which totals.
During 2008 and 2009 the test results of students who had sat both tests were used as a means of comparison. The researchers emailed students who had done both tests and over 1000 volunteered. This number was added to the results already collected from 217 students. After careful sorting of the data, the sample size was just 1153. The test results and countries of origin were input, and the result was a comparative table.
Some weaknesses
The research had some weaknesses however. The students’ overall results were higher than the general population taking the tests. This is probably because volunteers were used, and those obtaining low scores are less likely to offer up their results. This affects the level of confidence at lower score levels.
Although the TOEFL iBT and IELTS both examine the same categories of language proficiency, it must be remembered that the two tests have been designed from different frameworks. TOEFL iBT is a computer-based test whereas the IELTS is a paper written test. This is why the researchers found that the correlation between the scores was, in some instances, moderate, indicating a questionable link.
The fact that volunteers were used in the sample is another weakness of the study and future research with a larger sample is recommended.