Six studies were included in the review (n=1,490, range 40 to 627). Four were randomised controlled trials (RCTs, n=528). A fifth RCT (n=335) had methodological flaws and was regarded in the review as non-randomised. The sixth study was non-randomised and had a matched control school (n=627). Only one study was double-blinded. Drop-out rates ranged from 5% to 51%. Only two of the studies analysed data by intention to treat.
School-based educational/motivational sessions (three studies): The one relevant RCT reported that at four weeks’ post intervention the likelihood of being smoke-free for five days was significantly higher in the intervention group (RR 2.51, 95% CI 1.25 to 5.03) analysed by intention to treat. Two non-randomised studies reported a significant impact on cessation rates in the intervention group. One of the non-randomised studies stratified the analysis by gender and reported that the intervention significantly benefited female but not male students.
Other interventions (three studies): No statistically significant difference in cessation rates was found between pregnant adolescents who received educational sessions with peer support and those who received educational sessions alone or usual care (one RCT). Neither was there any statistically significant difference in smoking outcomes between hospital-recruited adolescents who received a motivational interview and those who received a pamphlet (one RCT) nor between adolescents who received laser versus sham acupuncture (one RCT).