Second language oral fluency has long been considered as an important construct in communicative language ability (e.g. de Jong et al, 2012) and many speaking tests are designed to measure fluency aspect(s) of candidates’ language (e.g. IELTS, TOEFL iBT, PTE Academic).

Current research insecond language acquisition suggests that a number of measures of speed, breakdown and repair fluency can reliably assess fluency and predict proficiency. However, there is little research evidence to indicate which measures best characterise fluency at each level of proficiency, and which can consistently distinguish one proficiency level from the next. This study is an attempt to help answer these questions.

This study investigated fluency constructs across four different levels of proficiency (A2–C1) and four different semi-direct speaking test tasks performed by 32 candidates taking the Aptis Speaking test. Using PRAAT (Boersma & Weenik, 2013), we analysed 120 task performances on different aspects of utterance fluency including speed, breakdown and repair measures across different tasks and levels of proficiency.

The results suggest that speed measures consistently distinguish fluency across different levels of proficiency, and many of the breakdown measures differentiate between lower (A2, B1) and higher levels (B2, C1). The varied use of repair measures at different proficiency levels and tasks suggest that a more complex process is at play.

The non-significant differences between most of fluency measures in the four tasks suggest that fluency is not affected by task type in the Aptis Speaking test. The implications of the findings are discussed in relation to the Aptis Speaking test fluency rating scales and rater training materials.