CGL Study Guide 2026
Everything you need to pass the CGL exam in one place: the exam format, every topic to study, real practice questions with explanations, flashcards, and full-length practice tests. Free, no sign-up needed.
📋 CGL Exam Format at a Glance
📚 CGL Topics to Study (69)
✍️ Sample CGL Questions & Answers
1. Which element is required in a Proof Summary but NOT required in a Proof Argument?
A Proof Summary is a standalone, titled document that identifies the research question and presents the conclusion, while a Proof Argument may be embedded in a narrative without a formal title block.
2. Which statistical concept is most useful when evaluating the likelihood that two individuals with the same name in the same county are the same person?
Name frequency analysis alongside cluster research of associated individuals helps assess whether two same-name records refer to one person.
3. A researcher finds a death certificate listing a parent's birthplace as 'Germany' while earlier records say 'Prussia.' How should this discrepancy be interpreted?
Political boundaries changed over time, and informants often used current country names rather than the historic jurisdiction.
4. A lecturer is presenting on the Genealogical Proof Standard (GPS) to an audience of experienced researchers. How should the lecture approach differ from one given to beginners?
Experienced audiences benefit from deeper application, edge cases, and critical analysis rather than basic definitional review.
5. Which environmental factor poses the greatest risk to the long-term integrity of a stored DNA sample?
Heat and UV light cause DNA strand breaks and accelerate degradation, making them the primary environmental threats to stored samples.
6. What does 'GPS element 5' (a soundly written conclusion) require that distinguishes it from the other GPS elements?
Element 5 requires transparency — the written conclusion must show readers the logical path from evidence to conclusion so the reasoning can be scrutinized and replicated.