Author: Marguerite Alofa P. O’Brien-Melford, Sunliegh C. Gador

Abstract: This study investigated the effectiveness of ChatGPT as an instructional support tool in enhancing the explanation letter writing skills of Technical Writing students at Cebu Doctors’ University. It aimed to address students’ recurring difficulties in applying the correct format, organization, elaboration, tone, and grammar, language usage, and mechanics in formal written communication. Employing a quasi-experimental pre-test/post-test design supported by a perception survey, the research examined measurable improvements in students’ performance following a ChatGPT-assisted intervention that incorporated guided modeling, interactive feedback, and revision-based activities. Fifty (50) first-year students from the EXCEL-Med Program participated in the study. Data were analyzed using descriptive statistics and a paired sample t-test. Findings revealed statistically significant improvements across all five writing elements, with the largest effect observed in format, organization, elaboration, and tone, and a moderate improvement in grammar, language usage, and mechanics. Students’ perception ratings further indicated strong agreement that ChatGPT was easy to use, enhanced confidence and understanding, and effectively supported skill development. Overall, the study concludes that ChatGPT-assisted instruction significantly improves students’ explanation letter writing performance and fosters confidence and awareness in responsible AI use. The results emphasize the potential of integrating AI-based tools as complementary pedagogical aids that support the United Nations Sustainable Development Goal 4 (Quality Education) by promoting digital literacy, communication competence, and ethical technology use in higher education.

Keywords: AI-assisted instruction, ChatGPT, English teaching, explanation letter writing skills, Philippines

Article Info: Received: 13 Oct 2025; Received in revised form: 11 Nov 2025; Accepted: 15 Nov 2025; Available online: 18 Nov 2025

DOI: 10.22161/ijels.106.16