Reliability of a monitoring system for respiratory emergency room admissions

A respiratory emergency room admissions monitoring system (RERAMS) was set up in Barcelona between 1985-1989, in order to investigate asthma epidemics in the city. Information on emergency room admissions for asthma and chronic obstructive pulmonary disease (COPD) was recorded daily from the four main hospitals of the city. The present study aims at assessing the reliability and coverage of this monitoring system. Identification of asthma and COPD emergencies was repeated by a reference observer, following the same protocol to extract data as that used by the register. To assess the coverage of the monitoring system, information was collected over 28 randomly selected days, from the emergency room clinical records for the seven additional hospitals in the city with five or more daily emergencies. Identification of asthma emergencies was highly reliable (kappa value, kappa = 0.81) as was the discrimination between asthma and COPD diagnoses (kappa = 0.91). Reliability for emergencies classified as COPD was lower, but still good (kappa = 0.65). The monitoring system covered 76 and 78% of all Barcelona asthma and COPD emergency room admissions, respectively. Emergency room admissions from our monitoring system did not differ in terms of social and demographic characteristics from emergencies recorded at the other hospitals. We conclude that the monitoring system for the Barcelona respiratory emergency room admissions was highly reliable, which suggests that, when adequately collected, information from clinical records of respiratory emergencies could be used for environmental epidemiological purposes.