PMC

Validation of classification tree in different subgroups: the receiver-operating characteristic curve and the c-statistics. PCI, percutaneous coronary intervention.

Length of stay (day) in patients with different outcomes. In a histogram, number of patients with different outcomes (vary in colours) were stacked within each 2-day interval of the length of stay. For patients died within hospitalisation, the length of stay was similar with those who withdrew from treatment due to a clinical terminal status, and much less than those survived.

The classification tree for decision-making in the derivation cohort. To identify the subgroup with lower risk of in-hospital mortality in the classification and regression tree (CART) analysis, systolic blood pressure (≥100 mm Hg), age (<60 years old), gender (male) and infarct location (non-anterior) was the best independent discriminator step by step. This flow chart demonstrates the size (proportion of the derivation cohort) and average risk in the lower-risk group at each step. SBP, systolic blood pressure; STEMI, ST segment elevation myocardial infarction.

Flow chart: cohort for tool development and validation. To develop and validate the risk tool, we identified fibrinolytic-eligible patients, who had not received any reperfusion therapy. Eligibility was defined as patients with STEMI who arrived to the hospital within 24 hours of symptom onset and did not have contraindications to fibrinolytic therapy, including history of haemorrhagic stroke, active bleeding at presentation or any other physician-documented contraindication. We excluded the patients who were discharged alive within 24 hours or transferred to other hospitals. The mini-GRACE indicates the median and IQR of mini-GRACE risk score in each patients subgroup; GRACE, Global Registry of Acute Coronary Events; PCI, percutaneous coronary intervention; STEMI, ST segment elevation myocardial infarction.