Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Twin Discordance for Age of Substance Use Initiation
| Mean (standard deviation) |
|||
|---|---|---|---|
| Full Sample | Men | Women | |
| Age of tobacco initiation | 2.5 (2.4) | 2.8 (2.6) | 2.3 (2.3) |
| Age of alcohol initiation | 1.7 (2.0) | 1.8 (1.9) | 1.6 (2.0) |
| Age of cannabis initiation | 2.2 (2.3) | 2.1 (2.1) | 2.3 (2.4) |
Notes. Twin discordance for tobacco, alcohol, and cannabis initiation indicates the average absolute value of the difference in co-twins' reported ages of initiation for each substance.
