PICO

PICO is a framework that provides a structured approach for defining the eligibility criteria of a systematic review and for developing a targeted search strategy. It breaks down the research question into four key components: population (the specific characteristics of the patients of interest), intervention (the treatment, exposure, or diagnostic test being studied), comparator/control (the alternative intervention or control group for comparison), and outcomes (the specific results or effects that are being measured). PICOS and PICOST are variations of this classic framework. In these variations, the extra components refer to study design and time (i.e. the time frame within which the outcomes are assessed).