I still don't know if he is lying though, as the producer behind it, Phil Scuderi, Victor Miller (He claims he came up with the idea of a campsite setting) or Tom Savini could have brought any of those elements to the project.
Anyway we all know Italians rip off American films,
never the other way round.
Still I think Bava would had found the whole slasher sub-genre rather amusing, esp as he had already poked fun at the gialli genre all those years before.