Opioid dependence latent structure: two classes with differing severity?

In an in-treatment, opioid-dependent sample, there appears to be two classes of individuals exhibiting distinct patterns of abuse and dependence criteria endorsement and to differ on externalizing but not internalizing disorders. This study provides preliminary evidence that the proposed DSM-V opioid use disorder distinction between moderate and severely dependent people is valid. Class one participants were not only more severely dependent, but had greater odds for opioid overdoses, other drug dependence and antisocial personality disorder.