No evidence that same-language subtitles improve children’s reading fluency

High-profile campaigns in the UK, USA, and India have argued that same-language television subtitles may help children improve their reading. In this intervention study, we tested the causal hypothesis that exposure to subtitles improves children’s reading fluency. We tested 127 British children in Years 2 and 3 before and after a six-week home-based intervention, in which children were randomly assigned to an experimental group who watched television with English subtitles or a control group who watched television without subtitles. Children’s reading fluency was assessed via two standard tests of reading fluency and via their engagement with subtitles while watching videos, measured with eye-tracking. Results showed that both groups improved their reading fluency over six weeks. Crucially, there was no evidence that subtitle exposure (of around 66 hours on average) drove an improvement in reading fluency, or that a more intensive subtitle intervention provided any additional benefit. We conclude that same-language subtitles are unlikely to improve children’s reading fluency. However, the primary school reading curriculum has a positive impact on reading fluency that can be observed over a relatively short time-scale.