Effect of Dial-Out Prefix Change on 9-1-1 Calls at a Large State University.

Background: Accessing the emergency medical services system via 9-1-1 operators is an effective way for patients to seek urgent health care; however, technological advances and telecommunication practices inundate the 9-1-1 and emergency services infrastructure with unintentional calls that delay response efforts to legitimate medical emergencies.

Objective: To determine whether the change in university-wide dial-out prefix from "9" to "7" reduced unnecessary calls to a 9-1-1 call center.

Methods: This is a retrospective study conducted utilizing information obtained from the University of North Carolina at Chapel Hill (UNC) Department of Public Safety (DPS) call center. Call center calls received during pre-change, intervening, and post-change periods were included in the study. The cost savings, defined in time and money, resulting from the prefix change were also examined.

Results: A total of 33,646 calls were made during the study period (January 11, 2010 through December 31, 2012) and included in the analysis. The prefix change was found to reduce the rate of invalid calls to the call center by 319 calls per month, resulting in a 43% reduction in total calls to the call center while preserving the rate of valid calls. The largest decrease occurred in hang-up calls (a decrease of 232 calls per month), especially those originating from the university. The prefix change was found to save the UNC DPS telecommunications division approximately $798.82 per month and the police officer division approximately $3,874.95 per month.

Conclusion: A prefix change was not only beneficial to the UNC community but it also has potentially wide-reaching effects. A reduction of invalid 9-1-1 calls translates to telecommunicators having more time available to handle true emergencies, phone lines remaining available for true emergencies, and police officers dedicating more time and effort to matters that necessitate officer assistance. Based on the call decrease seen with the prefix change, this study may be used as evidence to advocate for a change of dial-out codes beginning with "9."