Formal evaluation of construction safety performance metrics and a case for a balanced approach

Measuring safety performance is crucial to making informed decisions that improve construction safety management. Traditional approaches to construction safety performance measurement primarily focus on injury and fatality rates, but researchers have recently proposed and tested alternative metrics such as safety leading indicators and safety climate assessments. Although researchers tend to extol the benefits of alternative metrics, they are studied in isolation and the potential weaknesses are rarely discussed, leaving a critical gap in knowledge.

To address this limitation, this study aimed to evaluate existing safety performance against a set of pre-determined criteria and explore how multiple metrics may be used together to optimize strengths and offset weaknesses. For a well-rounded evaluation, the study included three evidence-based assessment criteria (i.e., the extent to which the metric is predictive, objective, and valid) and three subjective criteria (i.e., the extent to which each metric is clear, functional, and important). The evidence-based criteria were evaluated using a structured review of existing empirical evidence in literature, while the subjective criteria were evaluated using expert opinion solicited through the Delphi method.

The results revealed that no construction safety performance measurement metric is strong in all evaluation criteria, but many weaknesses may be addressed through research and development. It was also demonstrated that combining multiple complementary metrics may result in a more complete evaluation of the safety systems because multiple metrics offset respective strengths and weaknesses.

The study provides a holistic understanding of construction safety measurement that may guide safety professionals in their selection of metrics and assist researchers who seek more reliable dependent variables for intervention testing and safety performance trending.