Our site (erowid.org) now contains over 10,000 unique documents and image written by thousands of authors. This information ranges from the extremely reliable to the completely false. As an example, we have nearly 2000 experience reports in our Experience Vaults, most submitted anonymously. These vary in quality from extremely reliable & well written to the poorly written and possibly fabricated.
The value of any specific piece is unique to that article and there is no way to make blanket statements about the huge amount of material on the site. Some of it is good, some of it is not. Things slip through, items get mislabeled, typos happen, etc etc. The site includes fiction, humor, and satire. A good example is the Fosters beer LSD recipe, this was originally written as a joke, a usenet 'troll' by the original author. We archive many documents which we know are not 'true', but which have value in some other way, whether historical, entertainment, or opinion.
Erowid (spring of 2001) is edited and maintained by two senior editors (earth & fire), but articles are submitted, reviewed, edited, and critiqued by hundreds of volunteers who range from the world leading experts in their field to 15 year olds with no formal training.
The site as a whole is a cross between a library and a journal, not as an authority. A database, not an expert. If there is a specific piece of data or document you'd like confirmed for accuracy, please specify the exact URL and the exact piece of information you are interested in.
In general, the question of "are your sources valid" is a very complex one. Erowid is most like a library, crossed with a journal. We work hard to provide accurate information, but we also archive things like historical documents and experience reports. Because of the sheer volume of the site, like a library, the question of whether all the available books are "accurate" is not possible to answer.
Is a piece of poetry "accurate"? Is a historical document which describes the state of knowledge about a substance in 1750 "inaccurate"? Each article or page generally needs to be looked at on its own merits.
One exception would be the standard format pages which exist for most substances and which are generally written by Erowid such as the law, chemistry, effects, or dosage pages for a substance. These pages have been put together from a multitude of sources and with the input of experts in many fields. Some of the information has never been published anywhere else (such as dosage information about uncommon illicit recreational drugs) and is based primarily on the testemony of those who have used the substances.