Breakthrough PainAdministration, BuccalFentanylAnalgesics, OpioidPainLabor PainPain MeasurementAcute DiseaseAnalgesicsPain ManagementOxidesTreatment OutcomeChronic PainAnalgesia, EpiduralPain, PostoperativePain, IntractablePrescription Drug MisuseDouble-Blind MethodStrokeNeoplasmsChronic DiseaseArthralgiaMedication ErrorsMedication AdherenceNeuralgiaPalliative CareQuestionnairesProspective StudiesAnti-Inflammatory Agents, Non-SteroidalPain ThresholdRetrospective StudiesRadionuclide GeneratorsTime FactorsLow Back PainBack PainSeverity of Illness IndexPatient SatisfactionQuality of LifeFollow-Up StudiesAbdominal PainNeck PainComorbidityMedication ReconciliationMedication SystemsMedication Systems, HospitalCohort StudiesPelvic PainPain PerceptionFacial Pain