Therefore, these labels apply to the site indexed as it stands, not the domain registration of the organization operating the site. A peer review journal or publication is one that requires acceptance by a review board that is independent of the journal's ownership or management. Documented publications and publishers produce works that provide some source of substantiation for their claims within the article or book. These are typically footnotes, appendices of clinical trials or relevant experience, etc. This type of publication is aimed at professionals, people who expect to judge the validity of information for themselves.
Undocumented publications are typically for lay audiences.
These tend to be more like newsstand magazines and less like professional journals. This categorization gives searchers a reasonable indication of whether or not the publication indexed is more or less likely to be suitable for their interest. These label whether the site sells something, directly or indirectly. Again, this will help searchers determine whether the site is suitable to their interest and to know whether or not the site's material might be biased by a sales intent. Secure, Not secure.