The main criterion for choosing a print or an electronic index is the currency of the information you need.

• Print indexes came first and are your primary access to older materials.
• Most electronic indexes began after 1980 and therefore do not include materials published before 1980.
• Some print indexes do not have an electronic equivalent.
• Some electronic indexes do not have a print equivalent.

To fully research many topics you will need materials published prior to 1980. To find this material, you need to use print indexes.

To determine how far back in the published literature you must go, you need to find out when an event occurred or an idea first appeared. Ask your instructor, your TA, or ASK A LIBRARIAN to help you.