Wikipedia:Don't hijack references
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 | This page in a nutshell: Don't just change the content supported by a <ref>. |
Sometimes you make an edit, in which information is altered or added to a page, when the previous information was referenced. Now, that's all right; not all references are accurate, new information can become available, and so on. However, in many cases, the altered or added information will be altered or added in such a manner that the citation referencing the previous information, appears to be referencing the new information as well. Altering numbers, as in census results, climate data, or production total tables, is a common example of this "reference hijacking"; less common, but still happening often enough to be noticed, is slipping in additional prose text inside a sentence that is followed by the citation tag. These are often good-faith errors by newbies, who simply overlook the existence, or don't know the purpose, of the <ref> tags. While it can be passed as a mistake, this trick is, however, also a favourite tactic of vandals.
Bottom line: don't hijack references. When changing a referenced content, add a new reference, or remove the original reference if it's erroneous and replace it with a {{citation needed}} tag, preferably an explained one {{citation needed|reason=your explanation of the issue}}, and with an edit summary repeating the same explanation of the issue. Don't change the numbers in the table and leave the original reference for the entire table; do the same as you would in the first case mentioned.
When adding wholly new information, make sure you are not adding it just before an existing <ref> tag. Adding new information in the middle of a paragraph that used a single citation at the end is, I admit, tricky, and a good argument for "don't reference a whole paragraph to one cite at the end" ...but still, if you're adding something: cite it!
See also
- WP:Citation underkill - An essay suggesting to cite every sentence