Abdomen, AcuteAbdominal PainAppendicitisTorsion AbnormalityAcute PainDiverticulitisMesenteric LymphadenitisDiagnostic ErrorsRadiography, AbdominalJejunal DiseasesDiagnosis, Computer-AssistedCholecystitisPainAcute DiseaseRupture, SpontaneousColonic DiseasesAppendectomyEnteritisIntestinal ObstructionAbdomenPeptic Ulcer PerforationPancreatitisMedical History TakingPeritoneal DiseasesTomography, X-Ray ComputedPhysical ExaminationChronic PainPain ManagementAmylasesPain ThresholdProspective StudiesAntibodies, AntiphospholipidPain, PostoperativePain MeasurementEmergency Service, HospitalBack PainPain, IntractableLow Back PainNeck PainPelvic PainPain PerceptionRetrospective StudiesSensitivity and SpecificityFacial PainIrritable Bowel SyndromePain, ReferredGastrointestinal DiseasesConstipationIleal DiseasesShoulder PainMusculoskeletal PainColonic Diseases, FunctionalTreatment OutcomeChronic DiseaseColitis, IschemicVisceral PainAnalgesicsIntestinal PerforationCecal DiseasesIntussusceptionNociceptive PainNeuralgiaLaparotomyPancreatitis, ChronicAnalgesics, OpioidFlatulenceDiarrheaHemoperitoneumEndoscopy, Digestive SystemAppendix