Abstract
Megaprojects frequently face cost overruns, delays, and inefficiencies due to their complexity and multi-stakeholder dynamics. As large-scale infrastructure projects with significant economic and social impacts, they demand innovative solutions to enhance performance and sustainability. Lean Construction (LC) offers a promising approach to achieving these goals, yet its adoption remains limited by various barriers. While prior studies have identified Critical Success Factors (CSFs), there is a lack of robust statistical validation on how these factors mitigate LC adoption challenges. To address this gap, this study employs a sequential mixed-methods approach integrating a systematic literature review to identify preliminary factors, followed by semi-structured interviews with industry experts to refine and validate these factors. A structured questionnaire was then administered to 379 construction professionals involved in megaprojects in China to gather quantitative data. Finally, Partial Least Squares Structural Equation Modeling (PLS-SEM) was used to examine the causal relationships between CSFs and LC Barriers (LCBs). Results show that CSFs significantly reduce LCBs, with Strategic Leadership (β = 0.243), Resource and Knowledge Availability (β = 0.193), and Process Improvement (β = 0.188) being most influential. The model demonstrates acceptable explanatory power (R 2 = 0.263), predictive relevance (Q 2 = 0.252), and effect size (F 2 = 0.356). This study provides the first empirically validated framework linking success factors with LC adoption barriers, offering actionable strategies for more effective implementation in complex project environments.