Is the sky the limit? Trends in ambulance usage in Sør-Trøndelag County, Norway, from 1997–2007

Methods We did a population-based data registry analysis. From the ambulance database for the county of Sør-Trøndelag data from the years 1997–2007 was retrieved. Missions were stratified by year and classification of urgency (ordinary, urgent and acute). Further, we calculated gender distribution and age averages for each year. Results 257 089 ambulance missions were identified. Number of missions increased from 19 233 in 1997 to 27 306 in 2007. Population-adjusted numbers revealed the same trend. While number of missions classified as ordinary was almost constant, the increase in total number of missions was attributed to an increase in urgent and acute missions.