Table 1: PICO employed in this systematic review.

P Patient, Population, or Problem How would I describe a group of patients similar to mine? Children with croup < 12 years of age.
I Intervention, Prognostic Factor, or Exposure Which main intervention, prognostic factor, or exposure am I considering? Prednisolone or dexamethasone
C Comparison or Intervention (if appropriate) What is the main alternative to compare with the intervention? Studies that examine prednisolone usage or compare prednisolone with dexamethasone
O Outcome you would like to measure or achieve What can I hope to accomplish, measure, improve, or affect? Measured symptom reduction, dosages and re-presentation rates.