Case control studies that randomly assign patients to either surgical or non-surgical treatment yield a relapse rate of approximately 14% at one year. It would be useful to know the relapse rate of patients who have, instead, been selected for a given treatment based on a thorough clinical evaluation, including physical examination and laboratory results (all characteristics forming the Alvarado Score) as well as radiological exams if needed or deemed helpful. If this clinical evaluation is useful,the investigators would expect patient selection to be better than chance, and relapse rate lower than 14%. Once the investigators have established the utility of this evaluation, the investigators can begin to identify those components that have predictive value (such as blood chemistry analysis, or CT findings). This is the first step toward developing an accurate diagnostic-therapeutic algorithm which will avoid the risks and costs of needless surgery.