The first citation needed under the epidemiology section comes from Luhr OR Antonsen K Karlsson M Incidence and mortality after acute respiratory failure and acute respiratory distress syndrome in Sweden Denmark and Iceland The ARF Study Group Am J Respir Crit Care Med Jun 1999 159 6 1849 61 However the statement above mine is correct and the actual figure is acually around 86 2 in 100 000 person years from Rubenfeld GD Caldwell E Peabody E Weaver J Martin DP Neff M Incidence and outcomes of acute lung injury N Engl J Med Oct 20 2005 353 16 1685 93