Testing the reliability and validity of risk assessment methods in Human Factors and Ergonomics

There is growing interest in the use of systems-based risk assessment methods in Human Factors and Ergonomics (HFE). The purpose of this study was to test the intra-rater reliability and criterion-referenced concurrent validity of three systems-based risk assessment approaches: (i) the Systems-Theoretic Process Analysis (STPA) method; (ii) the Event Analysis of Systemic Teamwork Broken Links (EAST-BL) method; and, (iii) the Network Hazard Analysis and Risk Management System (Net-HARMS) method. Reliability and validity measures were obtained using the Signal Detection Theory (SDT) paradigm. Whilst STPA identified the highest number of risks, the findings indicate a weak to moderate level of reliability and validity for STPA, EAST-BL and Net-HARMS. There were no statistically significant differences between the methods across analyses. The results suggest that there is merit to the continued use of systems-based risk assessment methods following a series of methodological extensions that aim to enhance the reliability and validity of future applications. <b>Practitioner summary</b> The three risk assessment methods produced weak to moderate levels of stability and accuracy regarding their capability to predict risks. There is a pressing need to further test the reliability and validity of safety methods in Human Factors and Ergonomics.