For example, a negative result can eliminate the need for unnecessary checkups and screening tests in some cases.
For all relationships additional contextual and genealogical information is required to confirm the nature of the relationship.
For genealogical relationships between second cousins once removed and 5th cousins a more careful approach is necessary and data needs to be collected from multiple family members.
In some cases Y-DNA and mt DNA data may also be of help.
For autosomal DNA testing one should always test the oldest generations first wherever possible - your parents, grandparents (if you are lucky), aunts and uncles.
For endogamous populations, genealogical relationships are frequently difficult to estimate beyond about the 2nd cousin level of relationship and require careful analysis.
Genealogical relationships beyond the 5th cousin level of relationship are more difficult to prove with autosomal DNA testing and, as a general rule, these can only be approached using triangulation.
By testing yourself as well as your parents you will be able to determine which segments have been inherited from which parent, and you will also be able to rule out coincidental (Identical by state) matches.
A two-parent/child trio also provides the best results for the purposes of phasing and chromosome mapping.
As always, students can win both a cash prize as well as genetics related materials for their school.
Teachers might consider using this contest as a way to engage students in some real-world debates as you start the school year, or as an opportunity to meet writing standards in the biology classroom.