RT Journal
A1 Andersson R
T1 Proportion of cases of perforated appendicitis: A bad measure of quality of care
JF Archives of Surgery
JO Archives of Surgery
YR 2011
FD July 1
VO 146
IS 7
SP 885
OP 886
DO 10.1001/archsurg.2011.168
UL http://dx.doi.org/10.1001/archsurg.2011.168
AB 
Camp et al1 assume that a high proportion of perforations is an indication of the low quality of the health care system. However, this may be very misleading. The proportion of cases of perforated appendicitis is positively related to the number of perforations and inversely related to the number of cases of nonperforated appendicitis. There is now clear evidence that perforation can rarely be prevented and that spontaneous resolution of nonperforated appendicitis is common.2 Variations in the proportion of perforations is therefore mainly determined by variations in the incidence rate of nonperforated appendicitis, whereas the incidence rate of perforated appendicitis is stable over different health care systems.3 An increase in the use of health care and diagnostic techniques can explain the recent report of an increasing incidence rate of nonperforated appendicitis in the United States.4- 5 A low proportion of perforations is therefore most probably an indication of a higher consumption of health care leading to more operations for mild appendicitis that would otherwise resolve. The proportion of perforations is therefore a bad measure of the quality of care. I would advice future investigators of this issue to use population-based data and analyze the results as incidence rates.