Critical factors affecting construction labor productivity: A comparison between perceptions of project managers and contractors

The present study aims to identify critical factors (CFs) affecting construction labor productivity (CLP) from the perception of project managers compared to contractors' viewpoint. By a comprehensive review of the previous studies, this study managed 45 CFs affecting labor productivity in the construction industry, which was grouped as primary 6 categories, including manpower, management, work condition, project, and external factors. A total of 203 valid samples were collected by 56 project managers and 147 contractors who completed a structured questionnaire survey according to their previous participation in or directly implementation construction projects. These CFs were ranked based on their relative important index and descriptive statistics (i.e., mean and standard deviation). The results' analysis indicated that the wide difference between project managers' and contractors' perspectives on the most influential factors impacting construction labor productivity.