To assess daily variations in ambulance calls for cardiovascular diseases (CVDs), mental and behavioral disorders, and external causes in Arkhangelsk, Northwest Russia, in 2000-2008.
A population-based study.
Data about all ambulance calls during the years 2000-2008 were obtained from the Arkhangelsk ambulance station. Information about patient's gender, age, doctor's diagnosis according to International Classification of Diseases, 10th revision, and the date of call were recorded. Pearson's Chi-squared tests were used for comparing proportions of ambulance calls across the week for CVDs (I00-99), mental and behavioral disorders (F00-F99), and external causes (S00-T98, V01-Y98). The ratio of incidence of ambulance calls on Saturday, Sunday, and Monday versus the rest of week was also calculated.