Chatbots, or conversational agents, used for the provision of health information can promote preventive behaviors, such as vaccination. This study aims to assess advertising preferences and strategies to disseminate a COVID-19 vaccine-focused, non-generative chatbot among social media users ages 18–34.
Guided by social identity theory, the authors designed a series of six iterative advertising tests to confirm which messaging, visual and targeting strategies best elicited engagement on Facebook and Instagram, as measured by link clicks, chatbot messages sent and cost per message.
Audience targeting, messaging and visual design choices worked synergistically to reduce advertising costs, with costs dropping by 86% for the final ads when compared to earlier ads. Preferences diverged by gender and language (English or Spanish). It was more cost-effective to target broad audiences than audiences interested in health. Both male and female users showed a preference for video ads over image-based ads. Further, message framing altered online engagement with the chatbot via advertisements, with Spanish-speaking audiences seeming to prefer messages highlighting user empowerment and collectivist orientation.
Research on strategies to disseminate digital tools aiming to encourage preventive health behavior in real-world online conditions is largely lacking. Social media advertising offers a pathway to enhance the adoption of digital tools, such as chatbots, but ads must do more than accomplish clicks and page views to demonstrably foster user engagement, with such engagement being a pathway to influence health behavior. Explicating the value of audience segmentation and content-testing can help health agencies and partners plan to maximize user interactions and minimize costs with their marketing strategies. Health advocates should use theory-based, data-driven and user-responsive advertising strategies to combat the rise of health misinformation.
