Background questions ask for general knowledge (who, what, how, why, when) about a health condition, syndrome, issue or disease. Examples:

• How does diet during pregnancy affect birth weight?
• When do complications of whooping cough usually occur and in what age groups?

Textbooks, government websites, and other types of secondary sources are usually the best sources for answers to background questions.

Foreground (Clinical) Questions

Clinical (or patient-centered or foreground) questions ask for knowledge in relation to individual patients or case scenarios; they generally focus on etiology, diagnosis, therapy, and/or prognosis. Developing an answerable clinical question is crucial to efficiently searching the research literature -- and the PICO framework makes that easy! (See below.)

Research databases, such as PubMed and CINAHL, and/or clinical consult tools, such as UpToDate are most useful in answering clinical questions, which tend to be more complex than background questions, requiring higher-level search skills.