Well, if I remember the behind-the-scenes bit on this they're actually, specifically, talking about child abductions by strangers that, ultimately, will end in the child's murder anyway. (Not all kids who're abducted on a whole.)

It's 74% are murdered in the first 3 hours, and, yes, about 99% in the first 24 hours - according to the FBI's Crimes Against Children's division - it's why it's crucial for the police to get involved and start their investigation as soon as possible. ...I have more stats but, haha, they might only work to scare you more.