The CARS Checklist

Credibility
Accuracy
Reasonableness
Support

...is designed to provide some criteria for assessing the quality of a source, whether it is print or online. Few sources will meet every criterion in the list, and even those that do may not possess the highest level of quality possible. But if you learn to use the criteria in this list to critically evaluate the material you are reading, you will be much better able to separate the high-quality information from the poor quality. First, read the summary of the CARS Checklist below, then do the exercise that follows it.

Summary of the CARS Checklist for Research Source Evaluation

Credibility

If a source is credible, it is: Trustworthy; the quality of evidence and argument is evident; the author's credentials are available; quality control is evident; it is a known or respected authority; it has organizational support.
Goal: An authoritative source; a source that supplies some good evidence that allows you to trust it. Some questions to ask to determine credibility:

Is there sufficient evidence presented to make the argument persuasive?
Are there compelling arguments and reasons given?
Are there enough details for a reasonable conclusion about the information?

Accuracy

If a source is accurate, it is: Up-to-date, factual, detailed, exact, comprehensive, and its purpose reflects intentions of completeness and accuracy.
Goal: A source that is correct today (not yesterday); a source that gives the whole truth. In addition to an obvious tone or style that reveals a carelessness with detail or accuracy, there are several indicators that may mean the source is inaccurate, either in whole or in part:

No date on the document
Assertions that are vague or otherwise lacking detail
Sweeping rather than qualified language (that is, the use of always, never, every, completely rather than usually, seldom, sometimes, tends, and so forth)
An old date on information known to change rapidly
A very one-sided view that does not acknowledge opposing views or respond to them

Reasonableness

If a source is reasonable, it is: Fair, balanced, objective, and reasoned; there is no conflict of interest; there is an absence of fallacies or slanted tone.
Goal: A source that engages the subject thoughtfully and reasonably; a source concerned with the truth.

Here are some clues to a lack of reasonableness:

Intemperate tone or language ("stupid jerks," "shrill cries of my extremist opponents")
Overclaims ("Thousands of children are murdered every day in the United States.")
Sweeping statements of excessive significance ("This is the most important idea ever conceived!")
Conflict of interest ("Welcome to the Old Stogie Tobacco Company Home Page. To read our report, 'Cigarettes Make You Live Longer,' click here." or "When you buy a stereo, beware of other brands that lack our patented circuitry.")

Support

If a source is valid, it will have: Listed sources, contact information, and available corroboration its claims will be supported; documentation will be supplied.
Goal: A source that provides convincing evidence for the claims made; a source you can triangulate (find at least two other sources that support it).

Some source considerations include these:

Where did this information come from?
What sources did the information creator use?
Are the sources listed?
Is there a bibliography or other documentation?
Does the author provide contact information in case you wish to discuss an issue or request further clarification?
What kind of support for the information is given?
How does the writer know this?