Explicit Lifelong Learning Studies in Engineering Education: A Systematic Review and Thematic Synthesis of Project-Based Inquiry, Soft Skills, Employability, and Curriculum Embedding

Abstract

Lifelong learning is widely recognised as a core capability for engineers working under rapid technological, professional, and societal change. This article reports a PRISMA 2020-guided systematic review and thematic synthesis of engineering education publications that explicitly position themselves in relation to lifelong learning. Searches of Web of Science, ERIC, IEEE Xplore, and the ACM Digital Library in May 2026 identified 341 records; after duplicate removal and staged screening, 68 publications were included. The synthesis was organised around four recurrent thematic layers within this explicit lifelong learning corpus: project-based and inquiry-based learning, soft skills and motivation, employability-oriented capabilities, and curriculum and co-curricular embedding. Across the corpus, the literature was stronger at naming lifelong learning and proposing educational responses than at demonstrating how development was sustained across time and context. A recurring gap separated definition, design, and evidence: conceptual breadth and pedagogical variety outpaced cumulative developmental evidence. The review contributes an explicit-corpus synthesis, a layered interpretive framework for reading these recurrent supports, and implications for curriculum design, educational practice, and future research.