Evaluation of a national physical activity intervention for children: VERB campaign, 2002-2004.

Background: Amid concern for the consequences of physical inactivity among children, the Centers for Disease Control and Prevention started a campaign using commercial marketing methods to promote physical activity to children.

Design: Longitudinal study using a telephone survey to assess physical activity behaviors and attitudes at baseline and for 2 years of follow-up. Relationships of campaign awareness to behavioral and psychosocial effects were analyzed with use of propensity scoring.

Participants: Nationally representative cohort of 2257 parent-child dyads.

Intervention: Marketing campaign (VERB) directed to all U.S. children aged 9 to 13 years. Components included general market and ethnic-specific advertisements on television and radio, in print, and through promotions in communities, schools, and on the Internet. Advertising ran nationally at consistent levels from June 2002 through June 2004.

Main Outcome Measures: Psychosocial measures and self-reports of free-time and organized physical activity during nonschool hours in the week before the interview and on the day before the interview.

Results: After 2 years, a dose-response effect was detected in the study population. The more children who reported seeing VERB messages, the more physical activity they reported and the more positive their attitudes were about the benefits of being physically active. Children aware of VERB reported engaging in significantly more physical activity than children unaware of VERB. These results were considerably stronger than the effects after Year 1, which were only for physical activity among subpopulations.

Conclusions: The VERB campaign continued to positively influence children's attitudes about physical activity and their physical activity behaviors and expanded the effects to more children. With adequate and sustained investment, health marketing shows promise to affect the attitudes and behavior of children.