PainPain ManagementChronic PainPain ThresholdBack PainPain, PostoperativeAbdominal PainPain MeasurementDepressionLow Back PainNeck PainPain, IntractablePelvic PainPain PerceptionQuestionnairesFacial PainSeverity of Illness IndexAcute PainPain, ReferredPsychiatric Status Rating ScalesTreatment OutcomeShoulder PainPrevalenceAnxietySymptom AssessmentQuality of LifeBehavioral SymptomsMusculoskeletal PainProspective StudiesGastrointestinal DiseasesChronic DiseaseRisk FactorsDepressive DisorderFollow-Up StudiesCross-Sectional StudiesTime FactorsFatigueHallucinationsAnalgesicsUrination DisordersAffective SymptomsComorbidityPsychophysiologic DisordersGastroesophageal RefluxLongitudinal StudiesArthralgiaNeuralgiaStress, PsychologicalIrritable Bowel SyndromeConversion DisorderDelusionsNociceptive PainMagnetic Resonance ImagingConstipationOccupational DiseasesCoughPsychotic DisordersSchizophreniaRetrospective StudiesFibromyalgiaSchizophrenic PsychologySex FactorsMusculoskeletal DiseasesAge FactorsPremenstrual SyndromeDyspareuniaTomography, X-Ray ComputedIrritable MoodCohort StudiesHot FlashesAnalgesics, OpioidParesthesiaCognition DisordersStress Disorders, Post-TraumaticDyspneaSyndromePsychometricsAsthmaSleep DisordersDisability EvaluationNervous System DiseasesDizzinessHeartburnDyspepsiaNeuropsychological TestsPersonality InventoryAntidepressive AgentsMyofascial Pain SyndromesHyperalgesiaActivities of Daily LivingComplex Regional Pain SyndromesSleep Disorders, IntrinsicAffectDiagnostic Techniques, Digestive SystemAcute DiseaseVisceral PainLower Urinary Tract SymptomsSomatoform DisordersRespiration DisordersRegression Analysis