Methodological consistency for quantitative analysis and reporting in project delivery system performance research

The project-based nature of construction means that a unique team of designers, contractors, and specialty trade partners must be assembled for the delivery of each new asset. The decisions around how these parties are procured and contracted can have downstream consequences for the success of those delivered assets, both in the timeliness and cost-effectiveness of the project, as well as in meeting the long-term needs of the client. Over the last 20 years, this Journal has published several studies that statistically compare cost and schedule performance between two or more project delivery systems. New and emerging alternative project delivery systems have recently been included in these studies. However, greater consistency in the data collection, analysis, and reporting practices are needed in the published literature around the topic of project delivery systems to allow for comparisons of studies, identifying trends over time, and understanding this body of knowledge. This article presents a review of the research methods used in 30 empirical papers published in leading construction engineering and management journals that studied the performance of different project delivery systems. These papers serve as a basis to identify successful practices and propose a set of recommendations for more consistent quantitative research in this field. The authors argue that greater consistency in project delivery research is critically needed, proposing a path forward that will assist researchers in conducting more reliable project delivery research for years to come. The paper is structured around three main categories of recommendations: (1) overcoming bias in project delivery data collection, (2) making a fair comparison, and (3) standardizing the presentation of results. In each category, the authors identify successful practices from published papers and make specific recommendations that provide a consistent standard for future studies. The vision of the authors is that the recommendations advanced in this paper, derived from exemplary cases of published work, will start a dialogue in the construction, engineering, and management community about establishing a standard of practice for quantitative project delivery system research. This article can be used as a resource for peer-reviewers and editors evaluating a project delivery study's readiness for publication, and for faculty and graduate students looking for consistent guidance in conducting project delivery studies.