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Skillbuilding: Guidelines for Evaluating Genealogical Resources

From OnBoard - Newsletter of the BCG
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Linda Woodward Geiger, "Guidelines for Evaluating Genealogical Resources," OnBoard 14 (May 2008): 14-15.

Genealogical resources come in all shapes and sizes—paper documents created by a governmental agency; paper records created by private agencies such as churches, newspapers, and fraternal organizations; photographs and paintings; dairies and journals; tombstones, etc. As we gather genealogical facts and background we must be careful to consider the many facets that each record provides.

Elizabeth Shown Mills explains the process of analyzing evidence in a simple model. The following has been adapted from her models:


We need to process every resource by examining every fact and clue. Only then are we able to draw reasonable conclusions. The process includes identifying three basic elements.

  • Source type—is it an original or a derivative?
  • Information type(s)—is each piece primary or secondary?
  • Evidence type(s)—is each piece direct or indirect?

Original or Derivative?

A source is original if it is the first written statement, photograph, or recording of an event. Subsequent copies are derivatives and may be reproduced by hand, machine, camera or scanner; they may be reproduced on paper, in microform, as photographs or digital images, or in any other medium that records the image whether transcribed by hand or technology. Derivatives include the clerk’s copy of deeds (the originals are in the possession of the grantee), transcripts, abstracts, and notes produced from viewing the original or a derivative. In some cases various generations of derivatives exist, and frequently there is no record of the generation number. By way of example, Marriage Book A in the Probate Court of Hall County, Georgia, is a copy of the first clerk’s volume which had became worn. Subsequent copies may prove to be problematic. Following are ome scenarios that may occur:

  • Every handwritten or typed copy is prone to additional errors caused by mistakes in deciphering the hand-writing of the document being processed. Typographical errors may occur; the current copier may be careless about punctuation and/or spelling.
  • Sometimes documents may have been interlined with additional comments (generally in a smaller size and as a superscript), which may not be copied.
  • An original document may contain additional comments written with a different pen or ink type that strongly suggest they were not made at the time the document was created; but a copy made later may not indicate that the comments were not in the original document. Microform and grayscale digital copies do not allow the viewer to access variations in color or equipment and a comment added to a 19th century document with a blue ballpoint pen would probably not be evident to the reader of the microform or grayscale derivative.

Trained genealogists and historians need to make every attempt to get as close to the original as possible. Correct analysis may rely on such diligence.

Primary or Secondary?

A piece of information is primary when it is recorded by a knowledgeable eyewitness or participant in that event, or by an official whose duties require him or her to make an accurate record of the event when it occurs.

Secondary information is supplied by someone who was not at the event and may include errors caused by memory loss or influenced by other parties who may have a bias or be under emotional stress.

It is not at all unusual for documents to contain a combination of primary and secondary information. Examples include death records, tombstones, pension records, marriage applications, etc. Consider a death record: primary information may include the name and residence of the deceased, date and place of death, cause of death, sex, marital status, and name of the surviving spouse. Secondary information is supplied by an informant who does not have primary knowledge; such information may relate to date and place of birth of the deceased as well as names and residences of the deceased’s parents.

Direct or Indirect Evidence

Direct evidence is any fact that is explicitly stated, while indirect evidence is inferred from one or more pieces of evidence within the record. It isn’t surprising, then, that some evidence within a record may be direct while other evidence is indirect. Sometimes, there is no direct evidence, or there is conflicting evidence that necessitates the use of the Genealogical Proof Standard.

The Evaluation Process

In order to reach reasonable conclusions, it is essential to perform a complete analysis of each resource. The process includes careful scrutiny of each fact (stated directly or implied) to determine plausibility, possible contradictory evidence, and impact on the particular research project.

At the same time, it is important to remember that a single genealogical resource is analogous to a single man—neither is an island, and neither stands alone. Every effort must be made to identify additional resources and connections to the particular project.

A precise discussion of evidence-evaluation standards (standards 19–34) is available in The BCG Genealogical Standards Manual. They should be studied carefully.

Each of us will be judged by our colleagues and professionals as well as by future generations. I want to be valued as a significant researcher who is careful and methodical—a genealogist who thoroughly analyzes and evaluates each and every piece of evidence and scrupulously acknowledges and explains possibly conflicting information.

Suggested Resources

The Board for Certification of Genealogists. The BCG Genealogical Standards Manual. Orem, Utah: Ancestry Publishing, 2000.

Devine, Donn. “Evidence Analysis,” in Professional Genealogy: A Manual for Researchers, Writers, Editors, Lectures, and Librarians. Edited by Elizabeth Shown Mills. Baltimore, Md.: Genealogical Publishing Co., 2006.

Leary, Helen F.M., Elizabeth Shown Mills, and Christine Rose. “Evidence Analysis,” in Virginia: Where a Nation Began: Program Syllabus, 1999 NGS Conference in the States, Richmond, Virginia. Arlington, Va.: National Genealogical Society, 1999.

Mills, Elizabeth Shown. Evidence Analysis: A Research Process Map. Baltimore, Md.: Genealogical Publishing Co., 2006.

———. Evidence Explained, Citing History Sources from Artifacts to Cyberspace. Baltimore, Md.: Genealogical Publishing Company, 2007.

Linda Woodward Geiger , CG, CGL

This article was originally published in OnBoard, BCG's educational newsletter and is protected by copyright. Individuals may download and print copies for their personal study. Educators are granted permission to provide copies to their students as long as BCG, OnBoard, and the appropriate author are credited as the source of the material. Republication elsewhere is not permitted.

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