Externally Consistent and Outside the Vacuum

How does that document or entry in a register of numerous entries compare to other documents or other entries in the register? Obviously the details identifying the specific individual are different, but other aspects of the item should be similar to other documents or entries?

If your document (a death certificate perhaps) is partially typed and partially handwritten are others? If different types of handwriting appear on the document are others similar? If parts of the document are left blank do others have the same blank spaces?

If the item of interest is an entry in a register of baptisms, are other entries similar to yours in how they are worded, phrased, and organized? Are there other pieces of information in most of the other entries that are not included in yours.

Page 22 of the second edition of the  Standards Manual written by the Board for Certification of Genealogists (BCG) mentions “external consistency” as a key element in source analysis. I’ve always referred to it as looking at a document/record in context of others in the same set of records–pretty much the same thing.

No record or document is created in a vacuum.

Although if your research is very disorganized and tracked on small slips of paper some of those little bits of paper may end up in a vacuum, but that’s not what’s being discussed here.