6. Attending board-certified emergency physician places skin surface markers delineating region of abdominal tenderness, using an examination technique described below. Patient is marked with stickers while in supine position with arms above head, as required for CT. Attending board-certified emergency physician also places additional markers to blind radiological interpretation with respect to actual area of tenderness. Attending board-certified emergency physician is also asked to report the working diagnosis, treatment and disposition plan prior to CT scan being performed. An electronic standardized reporting form will be used. Reporting forms are designed in a format of electronic surveys and will be stored on password-protected server, designed specifically for research purposes. The information to be collected will be the same as the information in the attached appendices.