Interesting, but this kind of research tends to ignore the historical context. Anecdata: in ’70s LA ID bracelets started to be sold in schools. Why? Accident blood type yadda yadda, but I vividly remember darker talk that hinted at disappearances. That time and place was ground zero for a post-Manson, pre–McMartin American id that no one has pinned down. Guaran-f*cking-teed, that ID bracelet biz was an offshoot of the SoCal aerospace industry: it reeks of automated metal fabrication + data collection + a Vietnam-era dog-tag fetish with overtones of “missing” — a la POW–MIA nonsense. Origins like that important because data-collection culture in the US has long had a morbid edge to it. To understand that we need more Pynchon than stat-mongering.