Chapter 5

Scale anchoring methodology for developing revised performance level descriptors for the TOEFL iBT® test

A scale anchoring approach (Beaton & Allen, 1992) was initially used to develop empirically-based listening and reading performance descriptors for the TOEFL iBT® test, to help interpret scores. To further facilitate score interpretation, scores were also mapped to the Common European Framework of Reference (CEFR) levels through a standard setting study (Tannenbaum & Wylie, 2008), with revision to the score mapping results as additional data became available and feedback from score users was received (Papageorgiou et al., 2015). Although the two approaches, score mapping and scale anchoring, helped score interpretation from distinct perspectives, they also created some confusion for score users in that the performance levels from the two approaches were not fully aligned. The current study adopted a unified approach (Powers et al., 2017) to revise the performance descriptors of the scale anchoring approach by defining the proficiency levels based on the most recent CEFR score mapping results (Papageorgiou et al., 2015).  The performance descriptors evolving from this unified approach aimed to help us to address score users’ needs for score interpretation by referencing the widely known CEFR proficiency levels and by developing performance descriptors that were meaningful and relevant to the TOEFL iBT test.