An Experimental Study of Message Strategies for Mobile Alerts and Warnings

Dr. Dennis Mileti devoted his career to the study of public warnings disseminated through mass media, word of mouth, and, later, mobile technologies. To date, research on mobile public warnings has focused on standardized elements of messages (e.g., the common alerting protocol). During this same period, however, a variety of private, public, and governmental organizations have adopted mobile alert technologies to disseminate a diverse variety of free-form (nonstandardized) messages. We investigated how the evidence-based guidance developed for mobile public warnings applies to this broader class of free-form mobile alerts and warnings (FMAWs). This study reports an experimental comparison of US residents’ ($N=299$) reactions to notional free-form mobile messages about a safety risk. Experimental conditions compared messages that included safety instructions, ways to seek additional information, expressions of empathy, and emphasizing choice (“choice forward”). Results indicated that message efficacy was greater for FMAWs that gave safety instructions rather than just notifications. Choice-forward FMAWs produced both message efficacy and safety efficacy, or confidence that the person could make a good safety decision for the situation. Application: When the location, timing, and severity of an emergent risk are ambiguous, or when for public safety organizations, they have not yet reached a threshold appropriate for wireless emergency alert messages, a free-form message disseminated through mobile technologies or social media could use choice-forward language and links to more detailed information about possible self-protective action to facilitate just-in-time pre-event education and preparedness.

Thanks to the scholarship of Dr. Dennis Mileti, guidance for mobile public warnings, such as wireless emergency alert (WEA) messages, works. This guidance helps make people feel safer, and it is becoming standardized through technologies and practices, such as the common alerting protocol. Existing guidance applies to a specific set of circumstances: Experts have identified an imminent threat and can accurately predict its severity, location, and the single best way that people at risk can protect themselves. For many other situations, mobile alert technologies and social media messages may still be useful. These messages would be “free-form,” meaning not following a template or common alerting protocol, so understanding how existing wisdom about warnings applies is key. This study further suggests that free-form messages should empower recipients to seek additional information about a range of self-protective actions and to make the best choice for their individual situation.