Rapid reviews: definitions and uses.

This article is the first in a collaborative methodological series of narrative reviews on biostatistics and clinical epidemiology. This review aims to present rapid reviews, compare them with systematic reviews, and mention how they can be used. Rapid reviews use a methodology like systematic reviews, but through shortcuts applied, they can attain answers in less than six months and with fewer resources. Decision-makers use them in both America and Europe. There is no consensus on which shortcuts have the least impact on the reliability of conclusions, so rapid reviews are heterogeneous. Users of rapid reviews should identify these shortcuts in the methodology and be cautious when interpreting the conclusions, although they generally reach answers concordant with those obtained through a formal systematic review. The principal value of rapid reviews is to respond to health decision-makers needs when the context demands answers in limited time frames.