This is the Centor criteria for strep throat caused by strep pyogenes. The way I remember it is simply using the acronym LEAF. Let's start with the letter L for lymphadenopathy, specifically anterior cervical lymphadenopathy, E for exudates when you examine the throat. A for absence of cough, and F for fever of 38 degrees celsius. Each one of this components has one point, with 0 to 1 scoring not likely being strep throat, a score of 2 to 3 is uncertain, & patient may need rapid strep test with or without a throat culture which is more sensitive. 4 is very likely strep throat, where the clinician might choose to do rapid strep test or empirically treat with antibiotics such as amoxicillin. And there you go, L E A F leaf for centor criteria to calculate the probability of strep throat.