CRP and Pleural effusion: For example, a 54-month-old child with MPP has an 87.1% probability of SMPP, whose characteristics were fever days ≥ 7, AGR of 2, NLR of 3, CRP 20 mg/L, ESR 38 mm/h, MPV of 10 fL, coinfection, primary disease, no pleural effusion, and no wheeze (Fig. 2).