The aim of this study was to explore contributing factors identified in serious incident investigations conducted by internal, independent multidisciplinary teams.

A total of 166 serious incident investigation reports, conducted between 2018 and 2023 in 11 integrated social and health care organizations in Finland, were analyzed. The reports were classified by incident type and contributing factor, which were analyzed using the WHO’s Conceptual Framework for the International Classification for Patient Safety.

The results indicate considerable variation in the structure and content of serious incident investigation reports, with none specifying the investigation method used. The investigation reports of serious incidents revealed that in 79 (47.6%) cases, the consequences for the client or patient were fatal. The highest number of contributing factors was identified in investigations related to medication errors and errors related to treatment or monitoring. The number of contributing factors per investigation ranged from 1 to 16, with an average of 4.6. Most of the contributing factors were organizational or staff factors.

Investigating serious safety incidents provides valuable insights into event chains and helps organizations learn from past damages. Effectively promoting client and patient safety requires standardized methods and practices for examining adverse events. This requires a shared perspective and clear definitions of best practices. Consistent and effective investigation processes demand national and international collaboration to enhance safety and strengthen organizational learning.