Distribution of the duration of nonoccupational sick leave by medical diagnosis (Catalonia, Spain, 2006-2008)

We present a simple and practical tool that allows the usual distribution of the duration of non-occupational sick leave to be determined by medical diagnosis. A total of 2,646,352 episodes of medically certified sick leave, registered by the Catalan Institute of Medical Evaluations for the period 2006-2008, were followed to closure and were entered into a spreadsheet. Given its asymmetric distribution, the median duration of sick leave was 9 days. Musculoskeletal disorders were the most frequent diagnostic group (22.5%), while neoplasms had the longest median duration (56 days). The most common specific diagnoses were diarrhea-gastroenteritis (8.2%; median: 3 days) and acute rhinopharyngitis (5.2%; median: 4 days). The distribution of the duration of sick leave in a population varies by diagnosis and is asymmetric, with most episodes being much shorter than the mean duration. This finding is important for better clinical and administrative management of sick leave episodes.