Techniques to Minimize Bias When Using the Delphi Method to Quantify Construction Safety and Health Risks

Abstract

The dynamic and transient nature of construction projects makes construction engineering and management research particularly challenging. For example, experimental research on safety, risk management, innovation, and technology forecasting is often unrealistic due to the sensitivity and complexity of these topics. The Delphi technique, originally developed by the Rand Corporation to study the impact of technology on warfare, allows researchers to maintain significant control over bias in a well-structured, academically-rigorous process using the judgment of qualified experts. The Delphi method is particularly useful when objective data is unattainable, there is a lack of empirical evidence, experimental research is unrealistic or unethical, or when the heterogeneity of the participants must be preserved to assure validity of the results. In this paper, the authors review eight forms of bias that literature in the field of social psychology identifies as detrimental to judgment-based studies such as the Delphi method. Additionally, several techniques are reviewed that should be incorporated into the Delphi method to control for the identified biases. Special attention is focused on the use of these techniques when using the Delphi method to identify and quantify construction safety and health risks.