Replication of Strategic and Interactive Writing Instruction in a Nationwide Randomized Controlled Trial.

This study reports findings from a nationwide replication and the second randomized controlled trial (RCT) of Strategic and Interactive Writing Instruction (SIWI), a linguistically responsive framework for teaching writing to deaf students. A total of 50 teachers and their 294 students in grades 3-6 were randomly assigned to either SIWI or business-as-usual (BAU) instruction. Writing outcomes were assessed with trait-based rubrics and the Structured Analysis of Written Language (SAWL) in two genres (recount and information report), along with the Woodcock-Johnson IV broad written language composite and genre-specific motivation surveys administered at the beginning and end of the school year. Students receiving SIWI outperformed peers in the BAU group on writing traits across both genres, with effect sizes ranging from moderately large (d = 0.70) for informational reports to very large (d = 1.11) for recounts. On the SAWL, SIWI students demonstrated significantly greater gains in grammatical clarity on recount writing, as measured by the word efficiency ratio, with a moderate effect size (d = 0.64), although this effect was not observed for information reports. Students in the treatment group also reported significantly higher motivation for both genres. Unlike the prior RCT, no statistically significant differences emerged on the broad written language measure (d = 0.27). This may reflect spurious findings in the previous study or limitations in this study caused by the COVID-19 pandemic. Nonetheless, the effect size observed suggests some practical importance that warrants further investigation. Findings provide robust evidence that SIWI positively impacts deaf elementary students' writing development and motivation, particularly for recount genres, while underscoring the importance of replication for understanding the generalizability of intervention effects.