[Can diagnostic scoring systems help decision making in primary care of patients with suspected acute appendicitis?]

To assess two recently developed scoring systems with respect to making or excluding the diagnosis of acute appendicitis.

Data on 2359 patients with typical signs of acute appendicitis (AA) were analysed, the results of two diagnostic scoring systems being compared with the diagnosis made by an experienced surgeon.

AA was confirmed in 662 of the 22,359 patients (prevalence 28%). Sensitivity, specificity, positive and negative predictive values and overall accuracy for diagnosis with the Ohmann scoring system were 0.63, 0.93, 0.77, 0.86 and 0.84; with the Eskelinen score the values were 0.79, 0.85, 0.68, 0.81 and 0.835; and by the surgeon they were 0.90, 0.94, 0.85, 0.96 und 0.93. The negative appendectomy or laparotomy rate was 14.3 an 12.3 respectively with the Ohmann score, 29.5 and 26.6 with the Eskelinen score. The numbers of potential and of nondiagnosed perforations were 41% and 37% respectively with the Ohman score and 26.6% and 16.3% with the Eskelinen score. The number of missed cases of AA was lowest with the Ohman scoring system, compared with 1.8% for the surgeon. After excluding AA, both scoring systems had a specificity of -0.99, with a positive probability rate of at least 27 (Eskelinen score) up to 87 (Ohman score).

Both diagnostic scoring systems are better for excluding than correctly diagnosing AA; the decision to exclude could be made with a high degree of accuracy. Either scoring system may therefore be used in primary care of patients suspected of AA to help decide on referral to hospital.