Copies of all AMIS forms involving incidents classified as red response were sent to the project manager every other

week throughout the study. The EMCCs also sent copies of ambulance records from all red responses which involved ground or boat ambulances. In cases where doctors on-call, casualty clinics, PD0332991 chemical structure primary care doctors Inhibitors,research,lifescience,medical or air ambulances had been involved, copies of medical records were requested and collected separately. This collection of medical records continued also after the study period, until October 2008. To secure a uniform use of the variables in the AMIS program, a meeting was held between the persons in charge of the participating EMCCs. The severity of the medical problem was classified using The National Committee on Aeronautics (NACA) Score System based on all available information [12]. In the NACA system, the patient’s status is classified from Inhibitors,research,lifescience,medical 0 to 7, zero indicating no disease or injury, while seven indicates the patient being dead. NACA score was categorised in the analyses as NACA 0-1 (patient with either no symptoms/injuries or in no need of medical treatment), NACA 2-3 (patient in need of medical help, where value 3 indicates need Inhibitors,research,lifescience,medical of hospitalisation, but still not a life-threatening situation), NACA 4-6 (4 is a potentially,

Inhibitors,research,lifescience,medical and 5 and 6 are definitely, life-threatening medical situations) and NACA 7 (dead person). Based on information from all available forms and medical records the cases were also classified into symptom groups according to the International Classification of Primary Care – 2 (ICPC – 2) [13]. The analyses presented in the results-section are based on the patients who were given the code A10 – Chest pain. Results Inhibitors,research,lifescience,medical on all the clinical categories and symptom groups, are published in

a previous article [1]. Statistical analyses The statistical analyses were performed using Statistical Package for the Social Suplatast tosilate Sciences (SPSS version 15). Standard univariate statistics, including median and percentiles, were used to characterise the sample. Median, with 25th-75th percentiles, was used to analyse data where normal distribution was not present. Rates are presented as numbers of red responses per 1 000 inhabitants per year with a 95%-confidence interval (CI). Mann-Whitney U test was used for comparing age between males and females, for other comparisons the Pearson Chi-Square test was used. A P-value of < 0.05 was considered statistically significant. Ethics and approvals Approval of the study was given by the Privacy Ombudsman for Research, Regional Committee for Medical Research Ethics, and the Norwegian Directorate of Health.