Examining the relationships between posttraumatic stress disorder symptoms, positive smoking outcome expectancies, and cigarette smoking in people with substance use disorders: a multiple mediator model.

Cigarette smoking is highly prevalent in people with substance use disorders (SUDs) and is associated with significant physical health problems. Posttraumatic stress disorder (PTSD) is also highly associated with both SUDs and cigarette smoking and may serve as a barrier to smoking cessation efforts. In addition, people with PTSD are more likely to hold positive smoking outcome expectancies (i.