FerritinsOccult BloodHematologic TestsApoferritinsGuaiacIronColonoscopyMass ScreeningSigmoidoscopyColorectal NeoplasmsEarly Detection of CancerHemosiderinAnemia, Iron-DeficiencyImmunochemistrySensitivity and SpecificityEnemaBarium SulfateHemoglobinsTransferrinIron Metabolism DisordersUnnecessary ProceduresIron-Regulatory ProteinsPredictive Value of TestsIron OverloadReceptors, TransferrinDiagnostic Tests, RoutineReagent Kits, DiagnosticAdenomaIron RadioisotopesDeferoxamineHemochromatosisSiderosisBiological MarkersAnemia, HypochromicIron Chelating AgentsFerrous CompoundsFerric CompoundsIron Regulatory Protein 1Prospective StudiesTransketolaseCeruloplasminColonic PolypsImmunologic TestsColonography, Computed TomographicMelenaBlood Chemical AnalysisTime FactorsFecesRisk FactorsLiverPatient Acceptance of Health CareIndicators and ReagentsRetrospective StudiesPoint-of-Care SystemsLiver Function TestsDoping in SportsFalse Positive ReactionsCross-Sectional StudiesBlood SedimentationErythrocyte IndicesPostal ServicePatient ComplianceTuberculin TestFerrozineGastrointestinal HemorrhageIron-Binding ProteinsPhlebotomyHorsesEnzyme-Linked Immunosorbent AssayPrevalenceQuestionnairesROC CurveEndoscopy, GastrointestinalAge FactorsReproducibility of ResultsBreath TestsPractice Guidelines as TopicIron Regulatory Protein 2Liver DiseasesSex FactorsBloodlettingDiagnostic ErrorsColonic NeoplasmsFamily PracticeIron-Dextran ComplexRisk AssessmentFalse Negative Reactionsbeta-ThalassemiaHepcidinsHealth Knowledge, Attitudes, PracticeC-Reactive ProteinHemosiderosisPathology, ClinicalFollow-Up StudiesPilot ProjectsLogistic Models