Use the CARP criteria to evaluate your information sources:
Currency / Authority / Audience / Relevance / Reliability / Point of View or Purpose
NOTE: CARP (or CAARRP) is not a checklist that you can plug an article in and come up with a simple yes/no answer. Instead, it's a guide for thinking about different aspects of information, and making informed choices.
Here's a handy and useful chart:
CARP Criteria (.pdf)
Currency refers to how recently the source was published/updated.
Knowing when an article was published is important if only to put it into historical context. For instance, if you are researching a topic that is constantly changing, like technology or current events, you’d want the latest info. For factual information, like for your plant research, older materials should be ok because the basic characteristics of plants do not change, and confirming facts across sources helps too. Having material with a date of authorship is preferable, but not absolutely necessary if the source passes muster in the other criteria.
Authority and reliability work hand-in-hand to help us judge if the information on the webpage is accurate.
Authority refers to WHO has created the resource. Reliability refers to WHERE they are drawing their information from, and how we can tell.
We want to be using and learning from resources that have trustworthy information.
One way to do this is to try to use authored by people who have credentials or expertise in the field that they are writing about. The author
should have a degree, some proven expertise in the field. It might be they’ve owned a business for a long time, or have a name in their trade. Look for other materials published by the author. If they haven’t written a lot about your subject then be wary of their authority on the subject.
To judge reliability, we can look for a list of references or links to other sites that can help to verify the information. Perhaps other sources refer to the one you are evaluating. This is a good sign of reliability
These two points help you determine if the source will be useful to you, to answer your research questions.
"Audience" means asking who the information was written for. Is the information intended for people who do not have expertise in the field? Look at the terminology used in the article/on the website.
"Relevance" refers to how useful the source is for a specific use. When you have your topic in mind while you review the site, are you struggling to see how the site goes with your research? If so, question its relevance to your topic. The material may be credible and reliable, but it might not suit your information need. Do not try to force information sources to work for you.
This refers to the reason the webpage was created, and what perspective the author is coming from.
This one often takes the most effort to determine. If you are actively skeptical when you review for purpose/POV, you’ll find yourself questioning the overall purpose of the source through deeper reading. If the author is not clearly stating his/her reasons for writing the piece/developing the website, then you might want to look for bias which can sometimes be very vague or seem hidden. Sometimes the purpose of the source is to just inform, to report facts. If this is the case, then your skepticism should guide you to confirm those facts using a few other sources.
Using the CARP: A questionable site.
Using the CARP: An excellent site.
A note about Wikipedia
[Tip: Wikipedia has some very nice plant images....]