The Sheltered Instruction Observation Protocol (SIOP) Model and Oral Communication Outcomes in English as a Foreign Language: A Scoping Review

Abstract

Speaking is commonly regarded as the most challenging skill for EFL learners, yet pedagogical frameworks supporting its development in EFL classrooms remain inconsistently addressed. The Sheltered Instruction Observation Protocol (SIOP) Model was initially developed to help English learners cope with content subjects and simultaneously develop their language in North American classrooms. Although this model has been implemented in various international learning contexts, its impact on improving oral communication skills specifically has not been sufficiently documented. Guided by established scoping review methodology, this review examined empirical research featuring the SIOP Model in relation to its effect on oral communication or speaking proficiency among EFL learners. Records were retrieved from four databases, namely Web of Science, ERIC, Scopus, and Google Scholar, covering 2004 to 2025. Of 14,591 records identified, only two studies satisfied all eligibility conditions: an action research project conducted in Colombia and a mixed methods thesis conducted in Mexico. Neither study assessed oral proficiency using a structured measuring instrument, and both relied mainly on qualitative or self-reported data. These findings reveal a significant gap in the literature and suggest that assumptions about the effectiveness of SIOP in promoting oral proficiency among EFL learners still need further empirical investigation.