There are some oddities excluded/included. This is because it treats all credited actors the same, no matter the size of their role.
A film with three credited actors, where the male one has 8,000 lines of dialogue and is in every scene, while both the female actors get one scene and no dialogue each would count by this definition.
Whereas a film with that same scenario reversed wouldn't.
A better quiz would count up all female dialogue vs all male dialogue but that information isn't readily available.