Table 1.

Structured drug use variables from three harmonized studies and how they were categorized for repeated measure latent class analyses.

Name	CTN-0027	CTN-0030	CTN-0051	Drug category
Alcohol	Yes	Yes	Yes	Alcohol
Heavy Drinking	*	⁎⁎	Yes
Cannabinoids	Yes	Yes	Yes	Cannabis
Cocaine	Yes	Yes	Yes	Cocaine
Crack	*	No	Yes	Cocaine
Amphetamine	Yes	Yes	Yes	Amphetamine
Methamphetamine	Yes	Yes	No	Amphetamine
Opiates	Yes	Yes	Yes	Opioid
Benzodiazepines	Yes	Yes	Yes	Benzodiazepines
Propoxyphene	Yes	Yes	No	Opioid
Oxycodone	Yes	Yes	No	Opioid
Other	Yes	⁎⁎⁎	Yes
Morphine	No	Yes	No	Heroin
Hydromorphone	No	Yes	No	Heroin
Codeine	No	Yes	No	Opioid
Hydrocodone	No	Yes	No	Opioid
Sedatives Not Benzo	No	Yes	Yes	Depressants
Heroin/Opium	No	Yes	Yes	Heroin
Hallucinogens/MDMA	No	No	Yes	Hallucinogens
Buprenorphine	No	No	Yes
Inhalants	No	No	Yes

^⁎Can be calculated.

^⁎⁎Only a count of days.

^⁎⁎⁎If yes to opiates, then follow up for which drug.