Short-term effects of Project EX-4: a classroom-based smoking prevention and cessation intervention program

Researchers continue to try to develop effective teen tobacco use prevention and cessation programs. Three previous school clinic-based studies established the efficacy of Project EX for teen smoking cessation. This fourth study adapts Project EX to the classroom context. This paper reports the findings based on pretest and posttest surveys conducted immediately prior and post-intervention.

An eight-session classroom-based curriculum was developed and tested with a randomized controlled trial that involved a total of 1097 students in six program and six control continuation high schools. Program-specific knowledge and smoking measures were assessed at both the pretest and posttest surveys, and were used to evaluate the program's effect on the immediate outcomes. The immediate outcomes effects were analyzed with multi-level random coefficients models.

Program students provided favorable process ratings of the overall program and each session. Compared with the students in the control condition, students in the program condition showed a greater change in correct knowledge responses from pretest to posttest (beta=+5.5%, p=0.0003). Students in the program condition also experienced a greater reduction in weekly smoking (beta=-6.9%, p=0.038), and intention for smoking in the next 12 months (beta=-0.21 in 5-level scale, p=0.023).

EX-4 immediate outcome results revealed favorable student responses to the program, increases in knowledge, and decreases in smoking relative to a standard care control condition.