The overwhelming amount of available evidence in this information era poses a challenge to clinicians when it comes to taking decisions. It's not an easy task to decide based on solid scientific grounds rather than intuition, hearsay, or peer practice. Hence critical reading is a key tool to take evidence-based decisions. Decisions in ophthalmology care heavily rely on knowledge acquired in books, journals or another papers. Traditional view recognizes as valid any knowledge, regardless of its source or validity or if this is updated or not. Nowadays an updated medical knowledge will be supported on evidence-based medicine, using solid modern study designs and statistics; with the aim to weight the published evidence, no matter where those findings come from. This first article in the series gives us some elements to decide whether the proposed treatments for macular edema after cataract surgery are evidence-based. We will also review the basic skills needed to critical reading and evidence-based ophthalmology that allow us to take more reasonable decisions in order to obtain better benefit for our patients.