Table.

Characteristics and Outcomes of the Study Population

Study PopulationMissed Diagnosis Subgroupsb
VariableMissed Diagnosis Group, n=90Identified Diagnosis Group, n=1,178Relative Risk (95% CI)P ValueDischarged From ED, n=44Hospitalized With Wrong Diagnosis, n=47Relative Risk (95% CI)P Value
Age, years, median [IQR]a29 [18, 43]23 [14, 39]0.02332 [21, 44]23 [16,42]0.24
Sex
 Female38 (42.2)436 (37.0)1.22 (0.82, 1.83)0.3713 (29.5)26 (55.3)0.56 (0.34, 0.92)0.019
 Male52 (57.8)742 (63.0)31 (70.5)21 (44.7)
Symptom onset before first ED encountera
 >24 hours35 (44.3)584 (51.3)0.77 (0.50, 1.18)0.2511 (31.4)25 (55.6)0.56 (0.32, 0.98)0.042
 ≤24 hours44 (55.7)554 (48.7)24 (68.6)20 (44.4)
Symptom onset before eventual hospitalizationa
 >24 hours55 (64.7)584 (51.3)1.68 (1.09, 2.58)0.01831 (75.6)25 (55.6)1.66 (0.95, 2.90)0.07
 ≤24 hours30 (35.3)554 (48.7)10 (24.4)20 (44.4)
Time between ED first encounter and surgery, hours, median [IQR]b,c29.5 [21.6, 45.4]9.3 [6.7, 14.1]<0.00129.6 [21.4, 60.5]29.6 [21.6, 40.7]0.29
Surgical finding
 Complicated appendicitis49 (54.4)324 (27.5)2.87 (1.93, 4.27)<0.00119 (43.2)30 (63.8)0.65 (0.42, 1.00)0.06
 Not complicated41 (45.6)854 (72.5)25 (56.8)17 (36.2)
  • aMissing data: Age in 2 patients; symptom onset before first ED encounter in 51 patients (40/1,178 in identified group; 11/90 in missed group [9/44 in ED discharged subgroup and 2/47 in hospitalized in the wrong department subgroup; in 90 missed patients there were 91 events, see comment b below]); symptom onset before eventual hospitalization in 45 patients (40/1,178 in identified group; 5/90 in missed group [3/44 in ED discharged subgroup and 2/47 in hospitalized in the wrong department subgroup]); time between ED first encounter and surgery in 1 patient who refused surgery and following interval appendectomy had evidence of uncomplicated appendicitis.

  • bOne patient who was discharged from the ED and upon return was hospitalized with the wrong diagnosis in the wrong department was counted twice for a total of 91 events in 90 patients.

  • cPatients with diagnosis of periappendicular abscess are excluded.

  • Note: Data are presented as n (%) unless otherwise indicated.

  • ED, emergency department.