Found this with a film of Mary Cain's 4:14 1,500.
World Jr.: W 3:51.34 1997 Yinglai Lang, CHN
WTF!
Mary Slaney, the U.S. best of all time, ran 3:57.12.
If that isn't proof that the Chinese records are either drug-assisted or on a short track, I don't know what is...