 The objective of this study was to determine how many helicopter emergency medical services, HEMS, bases are necessary to reach the entire Norwegian population within 10 to 15 minutes. Using geographical location and population data from Norway's 428 municipalities, researchers estimated the number of HEMS bases needed to reach 99% or 100% of the population, within 15 minutes. They also calculated the number of personnel and associated costs needed to make the system cost effective. Researchers found that to reach 99% or 100% of the population within 15 minutes, 78 or 104 HEMS bases were needed, respectively. Additionally, they determined that the incremental need for personnel to go from 20 to 15 minutes was 602 or 728 personnel, with an accompanying incremental cost of 228 or 276 million euros per year. Finally, researchers concluded that the HEMS system as a whole would be cost-effective, but the least efficient bases would not be. This article was authored by Caroline Jean Jagdenberg, Audvar Yulberg, Gudrun Maria Wallerjournal, and others. We are article.tv, links in the description below.