Lykken, T. David. The Antisocial Personalities. Hillsdale, New Jersey: Lawrence Erlbaum Associates Publishers 1995. 259 pp.
Per Lykken in The Antisocial Personalities in 1995 put it this way (I am mostly paraphrasing here):
To qualify for antisocial personality disorder or APD, one must fit the following criteria (pg 3):
(1) they must be 18 yrs old or older
(2) the one diagnosing must be aware of “evidence of” antisocial behavior existing before the age of 15, or, as Lykken puts it, “with onset before the age of 15″
(3) must be upon critical examination found to be marked by a pervasive pattern of disregard for, and violation of, the rights of others
(4) in a way that disqualifies it from being considered merely or exclusively explainable by either Schizophrenia or manic episodes (remember: it’s pervasive and a pattern).