OPVL

The OPVL test is a tool to check the reliability of a source according to 4 criteria:

• ORIGIN
• PURPOSE
• VALUE
• LIMITATION

Origin: Where the source comes from.

Ask yourself the following questions:

• Who created the source?
• What is the creator’s background?
• When and where was the source created?
• When and where was the source published?
• In what format is the source presented?
• Is it a primary or secondary source?

Purpose: Why does the source exist.

Ask yourself the following questions:

• What does the source contain?
• Why was the source created (why does it exist?)
• Why was the source published (what is the goal of communicating this source)?
• Why was the source created in the format it is in?
• Who is the target audience (who is it for)?
• Does the source seek to inform, explain, persuade, or entertain?

Value: Why is this source useful for my investigation

Ask yourself the following questions:

• What does the source tell us about the author?
• How much authority does the author have on the subject matter of the source?
• Is the source trying to be objective or does it tend towards a specific point of view, or bias?
• Can you verify the source’s information with other relevant sources?
• How important is this source for the context of your inquiry?

Limitation: What restrictions does this source have

Ask yourself the following questions:

• How complete is the content of my source?
• What is the source’s point of view (bias)?
• What is the bias of the format or container?
• How removed is the source from the original source of information?
• To what depth does the source delve into the information that I need?