Most genealogy programs have no way of indicating that a claim is impossible (i.e. proved to be false), so genealogists are usually forced to delete these claims from their databases. This is an unfortunate practice that should not be necessary. Impossible claims should be accompanied by source references and text explaining why the claim is false. Impossible claims will not be considered when calculating birth date estimates or when determining improbabilities. Impossible claims are also highlighted on profile pages making it clear to all visitors that the claim is known to be false.
0 @I1@ INDI 1 BIRT 2 DATE 1 JAN 1900 2 SOUR @S1@ 2 _PROOF impossible
You can also use the built in GEDCOM tag for source reference quality (
QUAY) and set it to 0. Some users may set their source reference quality to 0 for other than impossible claims, so Gigatrees will display a
questionable reliability assessment. If you only use this tag for impossible claims, you may want to use the translate feature to manually replace the
questionable display text with
0 @I1@ INDI 1 BIRT 2 DATE 1 JAN 1900 2 SOUR @S1@ 3 QUAY 0
The following screenshot shows several impossible claims and their explainations. As you can see, keeping impossible claims has value in that is lets other researchers know which blind alley's they can avoid. If your explainations are not sufficient, however, it will not achieve that goal.