The PICO(TS) Method is used to take a research question and break it down into searchable concept groups. The acronym stands for:
P = patient, population, problem, phenomenon
I = intervention, exposure
C = comparison
O = outcome
T = timeframe
S = setting
There are many different ways to use this method, and there are no restrictions on how many concepts can be within each letter category. (For instance, you might have a patient and a problem.) I would caution against searching for outcomes; this could potentially cause selection bias in your search results where you only find results to support your hypothesis or argument.