This document introduces the PICO framework for constructing clinical questions to guide literature searches. PICO stands for Population, Intervention, Comparison, and Outcome. It provides examples of how to formulate each element of a PICO question using the scenario of a doctor asking why nebulizers were discontinued for an infant with bronchiolitis. Two sample PICO questions are constructed for this scenario to demonstrate how the framework can be applied to focus a literature search around relevant clinical issues.