The Cochrane Collaboration (http://www.cochrane.org) is an international, non-profit organization that prepares and disseminates up-to-date systematic reviews on the effects of healthcare interventions in order to help people make well-informed decisions. Systematic reviews have been introduced in recent years to reduce biases characterizing traditional (informal) literature reviews. They aim to answer focused healthcare questions by systematically identifying and evaluating all relevant research studies and synthesizing their results.