Smokefree Homes and Smoking Initiation in a National Sample
Abstracts
Initial Award Abstract |
|
Tobacco use is the most preventable cause of death and disability in the United States. Reducing the health consequences of smoking has been a key public health goal in the United States since 1964 and it is a primary goal for the California Tobacco Control Program.
The tobacco control literature suggests that an adolescent who grows up in a smoke-free home may have a lower probability of starting to smoke. In addition, it is not known whether the policy restrictions placed on tobacco marketing in the Master Settlement Agreement were sufficient to remove the influence of tobacco marketing on encouraging minors to start smoking. This study sets out to address these hypotheses by collecting additional data on an established, nationally representative cohort of families.
This nationwide cohort is comprised of 1,036 families who were identified using a random digit dialed telephone interview and enrolled in 2003-4 when their oldest child was aged 10-13 years. In 2007, there were 920 families still in the study. The study has prospective measures of smoke-free homes and receptivity to tobacco advertising at annual intervals over 5 years from participating teens, and baseline and one-year follow-up measures from participating parents. The current project will collect an additional (sixth) teen survey of smoking behavior and behavioral predictors when the teens are aged 17-18 years. An additional (third) parent survey will be collected to update data on parenting practices and adult smoking history. Parent and teen surveys will be undertaken by telephone, and scheduling of families will be conducted systematically by the age of the oldest child.
We will model adolescent progression on the smoking uptake continuum (never smoker to experimenter to established smoker) as a Markov chain, modeling time to transition to the higher smoking state using survival analysis techniques. We will evaluate the effect of smoke-free home and receptivity to tobacco advertising and promotions using hazard ratios from a parametric Weibull failure time model. A sensitivity analysis for estimated effect sizes and modeling assumptions will be obtained from a discrete time Cox regression model. Using this analytic approach, we will have 80% power to assess whether the early establishment of a smoke-free home reduces the probability of smoking initiation by at least 17% using a two-sided Wald test from the Cox Model. Similarly, we will be powered to identify whether receptivity to tobacco advertising and promotions (including the recent Camel #9 advertising campaign) as an adolescent is associated with a 20% increase in the probability of initiation by age 17-18 years. These analyses will be controlled for the following potential effects on smoking initiation: peer or parental smoking, and effective parenting practices for tobacco use prevention such as limit-setting on teen’s time allowed out at night, closeness of the parent-teen relationship, and consistent communication of anti-tobacco norms.
With multiple surveys of both parents and teens throughout adolescence, this cohort is ideal for the thorough exploration of a number of hypotheses testing the influence of public tobacco control policies on youth smoking uptake. Such exploration of these data offer the possibility of further refining hypotheses and their related intervention programs to prevent smoking initiation. |
