Tse R, et al. - In saltwater drowning when the immersion time is less than 1 hour (SWD1) and nonimmersion deaths, experts compared the diagnostic accuracies between lung-body (LB) ratio, postmortem vitreous humor sodium and chloride (PMVSC), and their combination in diagnosing SWD1. For analysis, classification tree models were used which revealed that most accurate in diagnosing SWD1 was the combination of PMVSC and LB ratio, followed by PMVSC and LB ratio. A measurable diagnostic improvement was established when both LB ratio and PMVSC were used. In aiding the diagnosis of SWD1, the developed tree models can be a reliable way, after adjusting for interlaboratory variations.