Factors associated with the length of stay of patients discharged from emergency department in France

Objectives The length of stay in the emergency department (ED) has been proposed as an indicator of performance in many countries. We conducted a survey of length of stay in two large areas in France and tested the hypothesis that patient and ED-related variables may influence it. Patients and methods During 2007, we examined lengths of stay in ambulatory patients, that is, excluding admitted patients. The following variables were considered: (a) at the patient level, age, sex, the day and month of the visit, and the French clinical classification of emergency patients (CCEP) class; (b) at the ED level, annual ED total number of visits, mean age, the proportions of patients less than 15 and more than 75 years, and the proportions of admitted and clinically stable patients with CCEP class 1 and 2. A multilevel hierarchical analysis was carried out. Results We analyzed 988 591 visits in 53 EDs. The ED-specific median length of stay was 98 (IQR: 62-137) min and the ED-specific median proportion of patients with length of stay of more than 4 h was 15 (5-24) %. There was a strong correlation between the ED-specific median length of stay and the ED-specific proportion of patients with a length of stay of more than 4 h (R = 0.96, P < 0.001). Using a multilevel analysis, only three variables were associated significantly with the length of stay: the age and the CCEP class of the patient, and the ED census. Conclusion We observed that the length of stay in the ED needs to be stratified by case mix and the total number of visits of the ED.