After LASSO logistic analysis, 18 risk factors were selected, including age, pleural effusion volume, ICU admission, eGFR, WBC count, proteinuria, platelet count, CRP, mechanical ventilation, contrast agents, NSAIDs, vancomycin/teicoplanin, spironolactone, loop diuretics, vasoactive agents, heart failure, pneumonia and CCI (Fig. 6). Here, CRP is linked to Pleural effusion.