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London Judgment and Decision Making Seminar

Mark Noort (Leiden University)

“Speaking-up to prevent harm: decision-making in times of danger”


Safety silence is the act of people withholding safety concerns, instead of raising these. Speaking-up (or ‘safety voice’) is essential for effective decision-making in times of danger (e.g., for identifying leading indicators of incidents, increasing performance) and where people have remained silent this has led to major organisational failures (e.g., Challenger space shuttle, Deep Water Horizon, Mid-Staffordshire hospital trust). Research on safety silence in high-reliability industries (e.g., aviation, healthcare) has proposed at least 32 variables to reduce safety silence. For instance, inclusive leadership practices, flat hierarchies, favourable policies. However, despite contributing important lessons, the vast majority of studies have utilised methods and data that provide few insights on the extent to which people decide to raise safety concerns and prevent harm. In particular, whilst it has been assumed that speaking-up can mitigate the momentum of hazards towards harmful outcomes, evidence on the nature of the behaviour and the mechanisms that explain the behaviour during simulated and real accidents remains limited. Without addressing this, the scope for improving decision-making on safety remains limited. To address this gap, across several experimental studies (n > 1200) and an analysis of ‘black box’ data from 172 aviation accidents, we addressed methodological challenges for investigating the nature of safety silence and safety voice, and developed the Threat Mitigation Model of safety voice and silence. This model has important implications for policy: i) safety voice is a distinct concept that is highly ecological and situated, ii) the phenomenon is important for understanding how ineffective decision-making can contribute to accidents, and iii) the model underscores that safety concerns, safety voice and safety listening all contribute to effective decision-making in times of danger.