Assessing writing performance in TOEFL-iBT

This study aims to determine the linguistic and discoursal differences in essays produced by Iranian test-takers of TOEFL-iBT in response to integrated and independent writing tasks. A sample of 40 essays, written by 20 Iranian test-takers of scored integrated and independent writing tasks, was compared and analyzed in terms of the four latent constructs of text easability (fourteen variables), cohesion (nine variables), lexical sophistication (nineteen variables), and syntactic complexity (six variables), using the Coh-Metrix 3.0 program. Results indicate differences in the linguistic and discoursal features of integrated and independent writing tasks. The findings reveal that the scores on writing tasks of EFL test-takers can be anchored empirically through the analysis of some discourse qualities like cohesion. Independent tasks contain more connectives and particles so they can result in better discourse structure organization and the generation of more cohesive devices. Stakeholders of the test should verify test constructs in terms of particular contexts like EFL and communicative views of language proficiency. Consequently, the findings contribute to the ongoing validity argument on TOEFL-iBT writing tasks for designing and interpreting scoring schemes for the writing component of the test.