likely to be significantP < 0.1
For multiple logistic analysis, we incorporated several important factors that were likely to be significant (at P < 0.1) and that avoided multicollinearity, as follows: elderly patients (> 65 years old), visit to the health care facility after 24 h, presence of fever, absence of abdominal tenderness, elevated CRP (above 10 mg/L), night shift, first visit to a teaching hospital, unavailability of urgent radiology reports, first visit to the clinic, and examination by a non-generalist.