Examples: general reference books [textbooks, compendia & review articles eg British National Formulary, Martindale, US Patient DI (2 vols - healthcare professional & patient), Microdex, MIMS] or online databases (MIMS, Micromedex, UpToDate) that summarises & evaluates info from many pri sources, allowing for rapid gathering of large amount of info & is easily accessible
(+): summarise large number of pri literature with evaluation/interpretation of info as well as relatively inexpensive
(-): most lag time (time taken to compile & summarise the diff pri literature), may not be most up-to-date on info (new info gleaned everytime with new pri sources but each tertiary source takes time to be revised with a new edition)