Abdominal PainCondimentsEndoscopesDuodenoscopyDyspepsiaEndoscopy, Digestive SystemPancreatitisTomography, X-Ray ComputedPainChronic PainPain ManagementAbdomen, AcutePain ThresholdPain, PostoperativePain MeasurementBack PainPain, IntractableLow Back PainNeck PainPelvic PainAcute PainPain PerceptionAppendicitisUpper ExtremityFacial PainGastrointestinal DiseasesIrritable Bowel SyndromePain, ReferredConstipationAbdomenIleal DiseasesShoulder PainTorsion AbnormalityTreatment OutcomeMusculoskeletal PainColonic Diseases, FunctionalChronic DiseaseIntestinal ObstructionRadiography, AbdominalUpper Gastrointestinal TractColitis, IschemicAnalgesicsIntestinal PerforationVisceral PainCecal DiseasesJejunal DiseasesIntussusceptionColonic DiseasesRetrospective StudiesRupture, SpontaneousProspective StudiesAcute DiseaseNociceptive PainNeuralgiaLaparotomyPancreatitis, ChronicAnalgesics, OpioidDiarrheaGastrointestinal HemorrhageFlatulenceVomitingAppendectomyHemoperitoneumFollow-Up StudiesAppendix