Four studies, two methods and one accident – another look at the reliability and validity of STAMP and Accimap for systemic accident analysis FilhoA.P.G. JunGyuchan Thomas WatersonPatrick 2017 The aim of this study was to assess the validity and reliability of two accident analysis methods. We identified four studies which analysed the same accident (the South Korea Sewol Ferry accident). Studies 1 and 2 used Accimap whilst Studies 3 and 4 applied STAMP. The four studies were compared in terms of analysis procedure taken, granularity of analysis, causal factors identified and recommendations suggested. The results indicate that the reliability between two STAMP studies (61%) is higher than two Accimap studies (31%) in terms of contributing factor identification. It was found that the recommendations made from each study reflect the focus and knowledge of the analyst.