Breakthrough PainAdministration, BuccalFentanylAnalgesics, OpioidPainLabor PainPain MeasurementAnalgesicsPain ManagementChronic PainAnalgesia, EpiduralPain, PostoperativePain, IntractablePrescription Drug MisuseDouble-Blind MethodNeoplasmsChronic DiseaseTreatment OutcomeArthralgiaMedication ErrorsMedication AdherencePalliative CareNeuralgiaQuestionnairesProspective StudiesAnti-Inflammatory Agents, Non-SteroidalTime FactorsPain ThresholdRetrospective StudiesLow Back PainSeverity of Illness IndexRadionuclide GeneratorsBack PainQuality of LifeFollow-Up StudiesPatient SatisfactionNeck PainAbdominal PainComorbidityMedication SystemsMedication ReconciliationCohort StudiesMedication Systems, HospitalPelvic PainPain PerceptionGene DosageFacial Pain