The 5 Ws is meant to be an easy way to remember what elements to assess when evaluating a source. It is not a checklist. The other methods listed on this page, the SIFT Method and Lateral Reading, can be used in conjunction with the 5 Ws to thoroughly evaluate a source.
Lateral reading is a method of investigating the source. It means that you don't rely only on the source you're evaluating, but branch out to use other resources like Wikipedia or using a search engine to find more information on the source itself.