Bull Sheana S, Posner Samuel F, Ortiz Charlene, Beaty Brenda, Benton Kathryn, Lin Lillian, Pals Sherri L, Evans Tom
Colorado Health Outcomes Program, University of Colorado Health Sciences Center, Aurora, Colorado 80045-0508, USA.
J Adolesc Health. 2008 Jul;43(1):71-8. doi: 10.1016/j.jadohealth.2007.12.009. Epub 2008 May 12.
To evaluate effects of a 6-month social marketing campaign on awareness of, attitudes toward and use of female as well as male condoms for 15-25 year-old-women.
Using a time-space sampling methodology, we conducted a cross-sectional survey of 3407 women at pre-campaign in 12 western U.S. neighborhoods on female and male condom awareness, attitudes, and use. Six of the 12 study neighborhoods were randomly selected to receive the POWER social marketing campaign designed to impact condom knowledge, attitudes, and use. The campaign was followed with another cross-sectional survey of 3,003 women in all 12 study neighborhoods on condom knowledge, attitudes, use and awareness of POWER materials. We compared pre-and post-campaign surveys to determine the efficacy of POWER and conducted post hoc analyses on post-campaign data to determine if exposure to POWER was related to higher levels of positive condom attitudes and norms and condom use.
We found no differences between neighborhoods with and without the POWER campaign with regard to our primary outcomes. To diagnose reasons for this null effect, we examined outcomes post hoc examining the influence of POWER exposure. Post hoc analyses show some evidence that exposure to POWER was associated with condom use. In the context of the nested trial, this raises concerns that post test only evaluations are limited.
Establishing the efficacy of a social marketing campaign is challenging. This group randomized trial showed a null effect. Social marketing campaigns may need to have more media channels and saturation before they can show behavioral effects. Using a nested design with randomization at the community level and probability sampling introduces rigor not commonly seen in evaluations of social marketing campaigns.
评估一项为期6个月的社会营销活动对15至25岁女性对男用和女用避孕套的认知、态度及使用情况的影响。
采用时空抽样方法，我们在美国西部12个社区对3407名女性进行了活动前的横断面调查，内容涉及对男用和女用避孕套的认知、态度及使用情况。从12个研究社区中随机选取6个社区，使其接受旨在影响避孕套知识、态度及使用情况的POWER社会营销活动。活动结束后，又在所有12个研究社区对3003名女性进行了横断面调查，内容包括避孕套知识、态度、使用情况以及对POWER材料的认知。我们比较了活动前后的调查结果以确定POWER的效果，并对活动后的数据进行事后分析，以确定接触POWER是否与更积极的避孕套态度、规范及避孕套使用水平相关。
在主要研究结果方面，我们发现接受POWER活动的社区与未接受该活动的社区之间没有差异。为找出这种无效结果的原因，我们进行事后分析以检验接触POWER的影响。事后分析显示，有证据表明接触POWER与避孕套使用有关。在嵌套试验的背景下，这引发了对仅进行事后测试评估存在局限性的担忧。
确定社会营销活动的效果具有挑战性。这项群组随机试验显示出无效结果。社会营销活动可能需要有更多的媒体渠道并达到更高的饱和度，才能显示出行为效果。采用在社区层面进行随机化和概率抽样的嵌套设计，引入了社会营销活动评估中不常见的严谨性。
