accurate family tree - Generations Genealogy

You can create a more accurate family tree if you dedicate time to identifying and fixing errors. This article will help you understand how family history errors occur and help you implement practices to minimise and fix them.

What are family history errors and how do they occur?

An error is an action or information which is inaccurate or incorrect.

There are three main types of family history errors:

errors that exist in sources and are mistakenly copied into a family tree
data entry errors that occur as information is entered into a family tree
errors resulting from mistakes made during the analysis of information, such as assumptions or misinterpretations.

Note: The term ‘sources’ means anything you obtain information from, including other people’s family trees.

Errors in sources

Errors in sources are usually the result of:

mistakes made by the creator of the source
errors in a source used by the creator of the source, or
incorrect information provided by an informant.

It is important to remember that all sources can have errors. However, here are some general rules about the likelihood of errors in a source:

Original sources may have fewer errors than derivative sources. Derivative sources are created using information from other sources and that increases the chances of errors occurring. However, as mentioned above, even original sources can have errors.
Contemporary sources may have fewer errors than sources created after the event. This is because sources created closer to an event are more likely to have access to reliable information about that event.
Official sources may have fewer errors than non-official sources, because they are often created in accordance with legislation or regulations.

Typed transcripts and indexes are derivative sources

Data entry errors

Common causes of data entry errors include:

a lack of familiarity with the program used to enter data, such as a family history software program or online family tree service
overlooking or ignoring details
imprecise copying of details.

Analytical errors

Analytical errors typically occur when:

no analysis is conducted
very little analysis is conducted, or
analysis is conducted but mistakes are made.

Common analytical errors include:

assuming that information in a source is accurate
assuming that a person with the same or similar name is the right person
failing to gather sufficient evidence from the best sources
accepting a search result without corroborating evidence
failing to consider alternatives
accepting information which was offered as a hint without first analysing whether it is correct information. As an example, read the article on Ancestry about the steps you should take to analyse green leaf hints.

Analytical errors can also occur due to misunderstanding, resulting from insufficient knowledge. For example:

misreading the text of a source, particularly with handwritten sources or poor-quality copies
difficulties with the language or the meaning of words
lack of familiarity with the format of information, the type of source, locations or place names.

handwritten letter with the writing written both horizontally and vertically — Crosshatch handwriting can be difficult to read

For more information about these types of mistakes, read my article about Mistakes and Misinterpretation.

Examples of family history errors

Here are some specific examples of errors to watch out for if you want an accurate family tree.

Incorrect or incomplete information, such as:

typographical errors or spelling mistakes
errors in the name or other details, such as birth or death information
names transposed, or names recorded in the wrong place on a form
information entered in the wrong place information that is entered in an inconsistent or incomplete manner, such as a date without a year, or inconsistent spelling of a place name
accidental or deliberate omissions, such as the removal of the names of children

An error in a transcription of a birth certificate, where the child’s surname has been omitted and his name has been recorded in the place that the father’s name should occur.

Other common errors include:

inclusion of the wrong person
creation of incorrect or inaccurate relationships between people
duplicate entries or people linked to each other more than once
a conclusion that is contrary to the available evidence.

Errors can also occur as a result of deficiencies in the research process, such as:

missing or poorly constructed source citations
including information in a family tree without citing sufficient reliable sources. The information itself may be accurate, but that accuracy cannot be demonstrated or tested without citing sources.
attaching a source citation to information which was not obtained from that source. For example, I often see sources cited for the date and location of birth, but the sources only mention the year. In such circumstances, additional sources should be provided for the location.

Avoid family history errors

Improve the accuracy of your family tree and minimise the risk of errors occurring by:

taking a systematic approach to research and developing your research skills
conducting a reasonably exhaustive search to find the best sources
critically analysing information and gathering sufficient evidence to reach reasonable and defensible conclusions
learning about the types of sources and the way that information is formatted in them (e.g. date formats)
studying the locations and places your family lived, and learning how the place names should be recorded
being meticulous in your data entry, verifying the information and proof reading your work.

Extract of a list of Maori place names . Guides to place names are useful tools for creating an accurate family tree — Consult guides to locations and place names

Identify errors in sources and your family tree

In addition to the strategies listed to avoid errors, to create an accurate family tree you should also:

be aware of common errors, and information patterns that may indicate errors (see checklist below)
gather more sources, as that will help to highlight inconsistencies
examine different versions of the same source
examine other sources about the same person
apply the FFANs technique
re-examine the sources you have already used and compare that information with the information in your family tree
compare your family tree to trees compiled by other researchers
analyse whether you have sufficient evidence to support your conclusions.

checklist of common family history errors to avoid so you can create an accurate family tree

See my article, Baptised Before Birth and Other Silly Claims.

Fix errors in your family tree

To create an accurate family tree, you need a systematic approach. This will make the task manageable and eliminate more errors.

Fix errors as you find them, or mark them to be fixed later.
Schedule regular maintenance and keep a record of where you are up to. Systematically work your way through your family tree, one generation at a time or one grandparent line at a time.
Conduct regular checks for missing source citations and poorly constructed source citations.
Use the tools provided by your family history software or online family tree service to check your tree for errors. For example, Legacy Family Tree software has a Potential Problems Report and Ancestry has Tree Checker feature in its Pro Tools.

A research plan can be a useful tool for reviewing your tree and listing remedial tasks.

Conclusion

Creating an accurate family tree requires implementation of good research practices. By understanding the types of errors that occur and being more systematic with your research, you can minimise errors and ensure your family history is as accurate as possible. Regularly reviewing and updating your tree will help maintain its accuracy.

For more tips on managing family trees, see my article: How to Manage Multiple Family Trees to Benefit Your Research.

More information

For more of my articles about analysing sources, go to the Analyse page.

For more of my articles about maintaining your family history, go to the Maintain page.

If you like this article, you will like my book, The Good Genealogist.

Featured image generated using AI apps in Canva, demonstrating the need to watch out for computer generated errors too!

For years, I confidently traced my great-great-grandmother Christina Malchow’s lineage through her father Gottlieb. After all, her parents married the same year she was born – the connection seemed obvious. Then my DNA results arrived. Christina wasn’t Gottlieb’s biological daughter. Years of research into the wrong family line, all based on a reasonable but incorrect assumption.

What are we aiming for when we say that we want good quality family history? Is having an accurate family tree enough, or are there other factors involved? And why is it so important that we have good quality family history?

Knowing the answers to these questions makes it easier to improve the quality of our family history.

Good quality family history has three main characteristics. It is accurate, comprehensive and well-documented.

Good quality family history rests on three essential pillars that work together to create reliable research: accurate, comprehensive and well-documented.

This post was originally published in June 2024 and last updated on 4 June 2025

1. Accurate family history

The correct people

An accurate family history has the correct people included. Each person is included because they are related to the person whose family history it is. They are family.

However, it is not as simple as this.

Relationships can be biological or non-biological. If the purpose of researching the family history is to research biological family, then the family history is inaccurate if it includes people who are not related biologically. On the contrary, if the purpose of researching the family history is to research family in the broadest sense, it is not made inaccurate by including non-biological relationships.

For example, my family history includes both my father’s biological parents and his adopted parents. It also includes the ancestors of both sets of parents. Including non-biological relationships in this case does not make it inaccurate, because that is my intent. His adopted parents were the people I knew as my grandparents. From my perspective, they are my family.

So, a judgement about the accuracy of a family history is partly dependent on the purpose of researching the family history. That purpose will vary depending on the intent of the researcher.

The correct relationships

An accurate family history has the correct relationships between each person. For example, it does not identify Person A as a sibling of Person B if Person A is actually a child of Person B.

Incorrect relationship or correct relationship in a family tree

Additionally, if a family history intentionally includes biological and non-biological family members, to be regarded as accurate it must distinguish between these different types of relationships. In the example above, my family history has two sets of parents for my father. One set is marked as biological and the other is marked as adopted.

You could also extend this principle further to other types of relationships. For example, if a woman marries for a second time, an accurate family history would mark the second husband as the step-father of the children from her first marriage.

Surnames can also mask true relationships. My 4x great-grandmother Mary Foran took her step-father’s surname when her mother remarried. Her birth surname was Leonard. Without distinguishing between her biological father (Leonard) and step-father (Foran), researchers could easily follow the wrong family line entirely.

The right information

An accurate family history does not have errors in the information.

Researchers create information errors:

when information is copied incorrectly into a family history
if a source contains incorrect information and that incorrect information is copied into a family history, and
when someone misinterprets the information in a source.

For more information about information errors, see my article: Mistakes and Misinterpretation.

Implications of an inaccurate family history

The main goal in researching family history is to identify and learn about family. Inaccurate family histories contain people who are not family, which means the main goal is not achieved.

An inaccurate family history makes it difficult to carry out further research and leads to more errors.

See my article, Family Tree Health Assessment Tool: Build a Solid Foundation.

Having the right people and correct relationships is essential, but accuracy alone isn’t sufficient for quality family history.

2. Comprehensive family history

Good quality family history is not just about accuracy. It also needs to be comprehensive.

A family tree chart that just contains names, for example, is not sufficient. Similarly, a family history that only traces the direct line is not sufficient.

Note: Direct line means the most direct line of ancestors or descendants. It excludes siblings. For example, father > father’s parents > their parents. (The Good Genealogist, Lautrec 2022, p187)

See my articles:

To be regarded as comprehensive, a family history also needs to include sufficient evidence to support the conclusions that have been made. For example, evidence should be obtained from more than one source and from the best sources.

This is the principle referred to as ‘reaching reasonable and defensible conclusions’. It is discussed in The Good Genealogist and also in my article How many sources should you use?

Similar to the situation with accuracy, a judgement about whether a family history is sufficiently comprehensive depends on the purpose of researching the family history. The people that are included and the information that is included should be consistent with that purpose.

This relates to the principle that family history should be based on a ‘reasonably exhaustive search’. Such a search examines all sources potentially relevant to the research question or hypothesis. For example, when researching a birth date, this means checking birth records, baptismal records, census records, and death certificates – not just stopping at the first source you find.

And, you need to explore offline family history sources as well as online sources.

Consequently, the family history should include all relevant information and people.

Even comprehensive research means little if you can’t substantiate your conclusions to others – or to yourself years later.

3. Well-documented family history

Good quality family history is well-documented.

This means that it is recorded systematically and comprehensively. It contains good quality source citations for each piece of information and has sufficient sources cited for each conclusion.

See my article How many sources should you use?

For more of my articles on documenting your family history, go to the Document page.

Accurate, comprehensive and well-documented

Good quality family history demonstrates all three characteristics. It is accurate, comprehensive and well-documented.

If there are weaknesses in any of these, it will affect the other. Poor documentation, for example, will usually make a family history inaccurate.

Good quality family history helps to ensure that we are researching our actual family. It also helps us do more research. When you have a solid foundation, every new discovery builds reliably on what came before.

Start by evaluating your current family history against these three pillars. Where are the gaps?

Addressing these weaknesses now will save you from the frustration of discovering errors years down the track – just like my experience with Christina Malchow showed me.

Quick Reference: The Three Pillars of Good Quality Family History

Accurate: Correct people, correct relationships, correct information

Comprehensive: Beyond names and dates – includes evidence, context, and reasonably exhaustive research
Well-documented: Systematic recording with quality source citations

Remember: Weaknesses in any pillar affect the others

Achieving good quality family history is the focus of the articles on this website, my book The Good Genealogist, and the courses and lectures that I present.

More information

For more of my articles about research methods for family history, go to the Research Methods page.

About the Author

Danielle Lautrec is a genealogy educator, researcher, and author of The Good Genealogist. With qualifications in history, family history, and historical archaeology, she teaches for the Society of Australian Genealogists.

Tag: accurate family tree

Create an accurate family tree by fixing errors