Background:
South Africa (SA) has enforced comprehensive tobacco control measures aimed at reducing tobacco use among the population. Tobacco control is especially important for young people because a lifelong addiction to nicotine is usually established in early teenage years. The impact of these tobacco control measures on trends in prevalence and frequency of cigarette smoking among SA youth have not been fully examined.

Methods:
Data was analysed from the four Global Youth Tobacco Surveys (GYTSs) conducted in 1999, 2002, 2008 and 2011. We assessed the prevalence and trends of current and frequent (smoked >=20 days in the preceding month) cigarette smoking by gender for grades 8 - 10 school learners. Logistic regression analysis with orthogonal polynomials was used to determine linear and non-linear trends from 1999 to 2011, controlling for age and race.

Results:
In boys, there was a significant linear decrease in current smoking from 28.8% (95% CI: 24.5-33.1) to 21.7% (18.5-25.0) across the four surveys (p=0.004). Frequent smoking in boys showed a significant linear decrease from 13.2% (9.8-17.5) to 7.8% (6.3-9.6) (p=0.015). In girls, there was a non-linear decrease in current smoking (p=0.028) from 17.5% (13.1-21.9) to 12.1% (9.9-14.4) and a significant nonlinear decrease in frequent smoking from 7.2% (5.2-10.0) to 1.9% (1.4-2.8) (p=0.004).

Conclusions:
In both boys and girls, the prevalence and frequency of cigarette smoking has showed significant declines. However, given that 16% of learners still smoke, increased efforts are required to address tobacco use among learners.