2021
Changes in ST segment elevation myocardial infarction hospitalisations in China from 2011 to 2015
Zhou T, Li X, Lu Y, Murugiah K, Bai X, Hu S, Gao Y, Masoudi FA, Krumholz HM, Li J, . Changes in ST segment elevation myocardial infarction hospitalisations in China from 2011 to 2015. Open Heart 2021, 8: e001666. PMID: 34599073, PMCID: PMC8488733, DOI: 10.1136/openhrt-2021-001666.Peer-Reviewed Original ResearchConceptsST-segment elevation myocardial infarctionPrehospital delayMyocardial infarctionSegment elevation myocardial infarctionProportion of patientsElevation myocardial infarctionAcute cardiovascular careAcute myocardial infarctionWeighted national estimateHealth service capacityRisk-adjusted ratesAcute reperfusionEligible patientsHospital deathReperfusion therapyMedical chartsPatient characteristicsHospital treatmentPatient outcomesRandom cohortCardiovascular diseaseCardiovascular carePatientsNational estimatesStandardised definitions
2020
Geographic Variation in Process and Outcomes of Care for Patients With Acute Myocardial Infarction in China From 2001 to 2015
Zhong Q, Gao Y, Zheng X, Chen J, Masoudi FA, Lu Y, Feng Y, Hu S, Zhang Q, Huang C, Wang Y, Krumholz HM, Li X, Zhou Y. Geographic Variation in Process and Outcomes of Care for Patients With Acute Myocardial Infarction in China From 2001 to 2015. JAMA Network Open 2020, 3: e2021182. PMID: 33095248, PMCID: PMC7584924, DOI: 10.1001/jamanetworkopen.2020.21182.Peer-Reviewed Original ResearchConceptsAcute myocardial infarctionProcess of careHospital mortalityMyocardial infarctionOdds ratioAngiotensin receptor blockersCross-sectional studyOutcomes of careReceptor blockersReperfusion therapyPatient characteristicsTherapy useCare measuresPatient hospitalizationIdeal patientOutcome measuresMAIN OUTCOMEΒ-blockersAMI managementPatientsEnzyme inhibitorsSignificant geographic variationMortalityCareHospitalizationUse of intravenous magnesium sulfate among patients with acute myocardial infarction in China from 2001 to 2015: China PEACE—Retrospective AMI Study
Wang X, Du X, Yang H, Bucholz E, Downing N, Spertus JA, Masoudi FA, Li J, Guan W, Gao Y, Hu S, Bai X, Krumholz HM, Li X. Use of intravenous magnesium sulfate among patients with acute myocardial infarction in China from 2001 to 2015: China PEACE—Retrospective AMI Study. BMJ Open 2020, 10: e033269. PMID: 32220910, PMCID: PMC7170603, DOI: 10.1136/bmjopen-2019-033269.Peer-Reviewed Original ResearchConceptsIntravenous magnesium sulfateAcute myocardial infarctionMagnesium sulfate useMyocardial infarctionMagnesium sulfateChina PEACE-Retrospective AMI StudyHospital-level variationProportion of hospitalsHospital-specific characteristicsMedian ORsSignificant initial decreaseReperfusion therapyCardiac arrestAMI careIneffective therapyPatient outcomesRepresentative sampleObservational studyMAIN OUTCOMEChinese guidelinesPatientsChinese hospitalsRoutine useAMI studyInfarction
2019
Trends in Performance and Opportunities for Improvement on a Composite Measure of Acute Myocardial Infarction Care
Desai NR, Udell JA, Wang Y, Spatz ES, Dharmarajan K, Ahmad T, Julien HM, Annapureddy A, Goyal A, de Lemos JA, Masoudi FA, Bhatt DL, Minges KE, Krumholz HM, Curtis JP. Trends in Performance and Opportunities for Improvement on a Composite Measure of Acute Myocardial Infarction Care. Circulation Cardiovascular Quality And Outcomes 2019, 12: e004983. PMID: 30871375, DOI: 10.1161/circoutcomes.118.004983.Peer-Reviewed Original ResearchMeSH KeywordsAgedCardiology Service, HospitalFemaleGuideline AdherenceHealthcare DisparitiesHumansMaleMiddle AgedMyocardial InfarctionOutcome and Process Assessment, Health CarePractice Guidelines as TopicQuality ImprovementQuality Indicators, Health CareRacial GroupsRegistriesSex FactorsSocioeconomic FactorsTreatment OutcomeUnited StatesConceptsProportion of patientsAcute myocardial infarctionDefect-free careHispanic patientsAMI careOlder patientsCare measuresNational Cardiovascular Data Registry Acute Coronary TreatmentIntervention Outcomes Network RegistryAcute myocardial infarction careGuideline-recommended pharmacotherapyMedicaid insurance coverageSociodemographic groupsMyocardial infarction careSafety-net statusGreatest absolute improvementComposite measureQuality of careHospital-level performanceCessation counselingEvidence-based processReperfusion therapyCardiac rehabilitationCoronary TreatmentVentricular function
2017
Urban–Rural Comparisons in Hospital Admission, Treatments, and Outcomes for ST-Segment–Elevation Myocardial Infarction in China From 2001 to 2011
Li X, Murugiah K, Li J, Masoudi FA, Chan PS, Hu S, Spertus JA, Wang Y, Downing NS, Krumholz HM, Jiang L. Urban–Rural Comparisons in Hospital Admission, Treatments, and Outcomes for ST-Segment–Elevation Myocardial Infarction in China From 2001 to 2011. Circulation Cardiovascular Quality And Outcomes 2017, 10: e003905. PMID: 29158421, PMCID: PMC6312853, DOI: 10.1161/circoutcomes.117.003905.Peer-Reviewed Original ResearchMeSH KeywordsAgedAged, 80 and overChinaDisease ManagementFemaleHealthcare DisparitiesHospital MortalityHospitalizationHospitals, RuralHospitals, UrbanHumansMaleMiddle AgedOdds RatioQuality ImprovementRetrospective StudiesRural PopulationST Elevation Myocardial InfarctionSurvival RateTime FactorsUrban PopulationConceptsEvidence-based treatmentsMyocardial infarctionEnzyme inhibitors/angiotensin receptor blockersRural hospitalsST-segment elevation myocardial infarctionUrban-rural disparitiesAngiotensin receptor blockersElevation myocardial infarctionAdjusted odds ratioResource-intensive careRisk-adjusted ratesHospital deathReperfusion therapyReceptor blockersHospital admissionCardiac facilitiesPatient outcomesOdds ratioCare persistUrban hospitalΒ-blockersBetter outcomesRural careHealthcare resourcesST segment
2016
China PEACE risk estimation tool for in-hospital death from acute myocardial infarction: an early risk classification tree for decisions about fibrinolytic therapy
Li X, Li J, Masoudi FA, Spertus JA, Lin Z, Krumholz HM, Jiang L. China PEACE risk estimation tool for in-hospital death from acute myocardial infarction: an early risk classification tree for decisions about fibrinolytic therapy. BMJ Open 2016, 6: e013355. PMID: 27798032, PMCID: PMC5093680, DOI: 10.1136/bmjopen-2016-013355.Peer-Reviewed Original ResearchConceptsST-segment elevation myocardial infarctionAcute myocardial infarctionFibrinolytic therapyLow-risk groupMyocardial infarctionHospital deathHospital mortalitySegment elevation myocardial infarctionCardiac Events (PEACE) studyHospital death riskComposite of deathElevation myocardial infarctionSystolic blood pressureTime of presentationRelative risk reductionCross-sectional studyBaseline mortality riskAcute reperfusionMajor bleedingReperfusion therapyBlood pressureDerivation cohortStudy cohortChina PatientValidation cohortAssociation of Guideline-Based Admission Treatments and Life Expectancy After Myocardial Infarction in Elderly Medicare Beneficiaries
Bucholz EM, Butala NM, Normand SL, Wang Y, Krumholz HM. Association of Guideline-Based Admission Treatments and Life Expectancy After Myocardial Infarction in Elderly Medicare Beneficiaries. Journal Of The American College Of Cardiology 2016, 67: 2378-2391. PMID: 27199062, PMCID: PMC5097252, DOI: 10.1016/j.jacc.2016.03.507.Peer-Reviewed Original ResearchMeSH KeywordsAdrenergic beta-AntagonistsAgedAspirinFemaleFollow-Up StudiesGuideline AdherenceHospitalizationHumansLife ExpectancyMaleMedicareMyocardial InfarctionPercutaneous Coronary InterventionPlatelet Aggregation InhibitorsPractice Guidelines as TopicThrombolytic TherapyTime-to-TreatmentUnited StatesConceptsAcute myocardial infarctionPrimary percutaneous coronary interventionGuideline-based therapyYears of lifeAdmission therapyLife expectancyMyocardial infarctionMedicare beneficiariesCox proportional hazards regressionAcute reperfusion therapyLate survival benefitReceipt of aspirinPercutaneous coronary interventionLong-term outcomesProportional hazards regressionCooperative Cardiovascular ProjectElderly Medicare beneficiariesDose-response relationshipAssociation of GuidelineShort life expectancyLonger life expectancyReperfusion therapyCoronary interventionD2B timeElderly patients
2015
10 year trends in urban–rural disparities in treatments and outcomes after ST-elevation myocardial infarction in China: insights from the China PEACE-Retrospective Acute Myocardial Infarction Study
Li X, Murugiah K, Li J, Wang Q, Hu S, Masoudi F, Spertus J, Downing N, Chan P, Krumholz H, Jiang L, Group C. 10 year trends in urban–rural disparities in treatments and outcomes after ST-elevation myocardial infarction in China: insights from the China PEACE-Retrospective Acute Myocardial Infarction Study. The Lancet 2015, 386: s2. DOI: 10.1016/s0140-6736(15)00580-2.Peer-Reviewed Original ResearchST-segment elevation myocardial infarctionCase of STEMIUrban hospitalRural hospitalsMyocardial infarctionAcute Myocardial Infarction StudyST-elevation myocardial infarctionMedical chart abstractionACEI/ARBMyocardial Infarction StudyElevation myocardial infarctionMedical record abstractionAdjusted odds ratioCertain clinical conditionsTwo-stage random sampling designQuality of careRisk-adjusted ratesCompleteness of documentationHospital complicationsHospital mortalityHospital deathReperfusion therapyChart abstractionComposite outcomeFamily Planning CommissionNational Quality Assessment of Early Clopidogrel Therapy in Chinese Patients With Acute Myocardial Infarction (AMI) in 2006 and 2011: Insights From the China Patient‐Centered Evaluative Assessment of Cardiac Events (PEACE)–Retrospective AMI Study
Zhang L, Desai NR, Li J, Hu S, Wang Q, Li X, Masoudi FA, Spertus JA, Nuti SV, Wang S, Krumholz HM, Jiang L, Group T. National Quality Assessment of Early Clopidogrel Therapy in Chinese Patients With Acute Myocardial Infarction (AMI) in 2006 and 2011: Insights From the China Patient‐Centered Evaluative Assessment of Cardiac Events (PEACE)–Retrospective AMI Study. Journal Of The American Heart Association 2015, 4: e001906. PMID: 26163041, PMCID: PMC4608074, DOI: 10.1161/jaha.115.001906.Peer-Reviewed Original ResearchMeSH KeywordsAgedAsian PeopleChinaClopidogrelDrug Administration ScheduleFemaleHealthcare DisparitiesHumansMaleMiddle AgedMyocardial InfarctionNational Health ProgramsPercutaneous Coronary InterventionPlatelet Aggregation InhibitorsPractice Patterns, Physicians'Quality ImprovementQuality Indicators, Health CareResidence CharacteristicsRetrospective StudiesRisk FactorsRural Health ServicesTiclopidineTime FactorsTreatment OutcomeUrban Health ServicesConceptsAcute myocardial infarctionEarly clopidogrel useClopidogrel therapyClopidogrel useRural hospitalsMyocardial infarctionQuality improvement initiativesEligible patientsClopidogrel administrationReperfusion therapyCardiac eventsHospital admissionAMI patientsChina PatientChinese patientsPatterns of useUrban hospitalPatientsClopidogrelChinese trialsHospitalTherapyEarly useAMI studyImprovement initiativesSex Differences in Reperfusion in Young Patients With ST-Segment–Elevation Myocardial Infarction
D'Onofrio G, Safdar B, Lichtman JH, Strait KM, Dreyer RP, Geda M, Spertus JA, Krumholz HM. Sex Differences in Reperfusion in Young Patients With ST-Segment–Elevation Myocardial Infarction. Circulation 2015, 131: 1324-1332. PMID: 25792558, PMCID: PMC4652789, DOI: 10.1161/circulationaha.114.012293.Peer-Reviewed Original ResearchConceptsST-segment elevation myocardial infarctionMyocardial infarctionReperfusion therapyAcute ST-segment elevation myocardial infarctionProspective observational cohort studyYoung AMI Patients (VIRGO) studyTime guidelinesYoung womenObservational cohort studyProportion of patientsElevation myocardial infarctionPercutaneous coronary interventionYears of ageSex differencesPatients 18Reperfusion strategyCohort studyCoronary interventionFibrinolytic therapyNeedle timeYounger patientsReperfusion delayRatio of womenReperfusion guidelinesSex disparities
2014
Trends in Early Aspirin Use Among Patients With Acute Myocardial Infarction in China, 2001–2011: The China PEACE‐Retrospective AMI Study
Gao Y, Masoudi FA, Hu S, Li J, Zhang H, Li X, Desai NR, Krumholz HM, Jiang L, Group T. Trends in Early Aspirin Use Among Patients With Acute Myocardial Infarction in China, 2001–2011: The China PEACE‐Retrospective AMI Study. Journal Of The American Heart Association 2014, 3: e001250. PMID: 25304853, PMCID: PMC4323779, DOI: 10.1161/jaha.114.001250.Peer-Reviewed Original ResearchMeSH KeywordsAdultAge FactorsAgedAspirinChinaCohort StudiesConfidence IntervalsDose-Response Relationship, DrugDrug Administration ScheduleFemaleHospital MortalityHumansMaleMiddle AgedMultivariate AnalysisMyocardial InfarctionOdds RatioRetrospective StudiesRisk AssessmentRural PopulationSecondary PreventionSex FactorsSurvival AnalysisSurvival RateUrban PopulationConceptsAcute myocardial infarctionMyocardial infarctionAspirin useEarly treatmentSegment elevation acute myocardial infarctionElevation acute myocardial infarctionEarly useChina PEACE-Retrospective AMI StudyEarly aspirin therapyEarly aspirin useLimited healthcare resourcesAspirin therapyCardiogenic shockChest discomfortReperfusion therapyRate of useChina PatientRetrospective studyPatient groupFinal diagnosisHealthcare resourcesInfarctionPatientsAspirinAMI study
2008
Delay in Presentation and Reperfusion Therapy in ST-Elevation Myocardial Infarction
Ting HH, Bradley EH, Wang Y, Nallamothu BK, Gersh BJ, Roger VL, Lichtman JH, Curtis JP, Krumholz HM. Delay in Presentation and Reperfusion Therapy in ST-Elevation Myocardial Infarction. The American Journal Of Medicine 2008, 121: 316-323. PMID: 18374691, PMCID: PMC2373574, DOI: 10.1016/j.amjmed.2007.11.017.Peer-Reviewed Original ResearchMeSH KeywordsAgedAged, 80 and overAngioplasty, Balloon, CoronaryEarly DiagnosisElectrocardiographyEmergency Medical ServicesEmergency Service, HospitalFemaleFollow-Up StudiesHospital MortalityHumansMaleMiddle AgedMultivariate AnalysisMyocardial InfarctionMyocardial RevascularizationOdds RatioProbabilityRegistriesRetrospective StudiesRisk FactorsSurvival AnalysisThrombolytic TherapyTime FactorsTreatment OutcomeConceptsST-elevation myocardial infarctionReperfusion therapyHospital presentationBalloon timeSymptom onsetLonger doorMyocardial infarctionDrug timePrimary reperfusion therapyCohort studyLate presentersNeedle timeNational registryPatientsReduced likelihoodTherapyInfarctionLong delayPresentationOnsetHoursAssociationMinutesRegistry
2007
Acute Reperfusion Therapy in ST-Elevation Myocardial Infarction from 1994-2003
Nallamothu BK, Blaney ME, Morris SM, Parsons L, Miller DP, Canto JG, Barron HV, Krumholz HM, Investigators R. Acute Reperfusion Therapy in ST-Elevation Myocardial Infarction from 1994-2003. The American Journal Of Medicine 2007, 120: 693.e1-693.e8. PMID: 17679128, PMCID: PMC2020513, DOI: 10.1016/j.amjmed.2007.01.028.Peer-Reviewed Original ResearchConceptsAcute reperfusion therapyST-elevation myocardial infarctionReperfusion therapyMyocardial infarctionIdeal patientPrimary percutaneous coronary interventionPercutaneous coronary interventionNational performance measuresChest painCoronary interventionFibrinolytic therapySymptom onsetNational registryPatientsTherapyInfarctionKey subgroupsAppropriate utilizationTime periodRecent time periodPainRegistryCohortContemporary useImportant opportunityIschaemic symptoms, quality of care and mortality during myocardial infarction
Schelbert EB, Rumsfeld JS, Krumholz HM, Canto JG, Magid DJ, Masoudi FA, Reid KJ, Spertus JA. Ischaemic symptoms, quality of care and mortality during myocardial infarction. Heart 2007, 94: e2. PMID: 17639097, PMCID: PMC3703470, DOI: 10.1136/hrt.2006.111674.Peer-Reviewed Original ResearchConceptsIschemic symptomsMyocardial infarctionQuality of careST-elevation myocardial infarctionACE/ARBNon-cardiac comorbiditiesPositive cardiac enzymesEvidence of infarctionHospital mortalityCessation counsellingHospital survivalReperfusion therapyCardiac enzymesConsecutive patientsMI careMI symptomsCare indicatorsPatient reportsSymptom recognitionChart documentationPatientsUS hospitalsSymptomsInfarctionCare
2006
Door-to-drug and door-to-balloon times: Where can we improve? Time to reperfusion therapy in patients with ST-segment elevation myocardial infarction (STEMI)
Bradley EH, Herrin J, Wang Y, McNamara RL, Radford MJ, Magid DJ, Canto JG, Blaney M, Krumholz HM. Door-to-drug and door-to-balloon times: Where can we improve? Time to reperfusion therapy in patients with ST-segment elevation myocardial infarction (STEMI). American Heart Journal 2006, 151: 1281-1287. PMID: 16781237, DOI: 10.1016/j.ahj.2005.07.015.Peer-Reviewed Original ResearchConceptsST-segment elevation myocardial infarctionPatients' clinical characteristicsBalloon timeClinical characteristicsDrug timeMyocardial infarctionProportion of patientsElevation myocardial infarctionHospital-level variationTreatment of patientsCross-sectional analysisHigh performing hospitalsReperfusion therapyNational registryHospitalPatientsRegression modelingECGDrugsInfarctionHierarchical regression modelingHospital performanceImportant quality indicatorMinutesGeometric meanThe Pre-Hospital Electrocardiogram and Time to Reperfusion in Patients With Acute Myocardial Infarction, 2000–2002 Findings From the National Registry of Myocardial Infarction-4
Curtis JP, Portnay EL, Wang Y, McNamara RL, Herrin J, Bradley EH, Magid DJ, Blaney ME, Canto JG, Krumholz HM. The Pre-Hospital Electrocardiogram and Time to Reperfusion in Patients With Acute Myocardial Infarction, 2000–2002 Findings From the National Registry of Myocardial Infarction-4. Journal Of The American College Of Cardiology 2006, 47: 1544-1552. PMID: 16630989, DOI: 10.1016/j.jacc.2005.10.077.Peer-Reviewed Original ResearchConceptsST-segment elevation myocardial infarctionPre-hospital electrocardiogramPrimary percutaneous coronary interventionMyocardial infarction 4Mean doorReperfusion timeHospital characteristicsNational registryTreatment of STEMILimited contemporary informationElevation myocardial infarctionPercutaneous coronary interventionBundle branch blockAcute reperfusionECG usePCI cohortReperfusion therapyBalloon timeCoronary interventionFibrinolytic therapyTherapy cohortMyocardial infarctionBranch blockNational guidelinesDrug time
2005
Performance of the Thrombolysis in Myocardial Infarction (TIMI) ST-elevation myocardial infarction risk score in a national cohort of elderly patients
Rathore SS, Weinfurt KP, Foody JM, Krumholz HM. Performance of the Thrombolysis in Myocardial Infarction (TIMI) ST-elevation myocardial infarction risk score in a national cohort of elderly patients. American Heart Journal 2005, 150: 402-410. PMID: 16169316, PMCID: PMC2790534, DOI: 10.1016/j.ahj.2005.03.069.Peer-Reviewed Original ResearchConceptsThirty-day mortality rateTIMI scoreElderly patientsMortality rateRisk scoreMyocardial Infarction (TIMI) risk scoreHigh TIMI scoreMyocardial Infarction (TIMI) scoreCommunity-based cohortReperfusion therapyTrial cohortPrognostic discriminationTrial populationNational cohortModest discriminationPatientsUS hospitalsSTEMICohortScore discriminationScoresThrombolysisSex and Racial Differences in the Management of Acute Myocardial Infarction, 1994 through 2002
Vaccarino V, Rathore SS, Wenger NK, Frederick PD, Abramson JL, Barron HV, Manhapra A, Mallik S, Krumholz HM. Sex and Racial Differences in the Management of Acute Myocardial Infarction, 1994 through 2002. New England Journal Of Medicine 2005, 353: 671-682. PMID: 16107620, PMCID: PMC2805130, DOI: 10.1056/nejmsa032214.Peer-Reviewed Original ResearchMeSH KeywordsAdrenergic beta-AntagonistsAgedAspirinBlack PeopleCoronary AngiographyFemaleHealth Services AccessibilityHospital MortalityHumansLogistic ModelsMaleMiddle AgedMyocardial InfarctionMyocardial RevascularizationPlatelet Aggregation InhibitorsProcess Assessment, Health CareQuality of Health CareRisk FactorsSex FactorsUnited StatesWhite PeopleConceptsUse of aspirinMyocardial infarctionReperfusion therapyCoronary angiographyRacial differencesTreatment of patientsHospital deathHospital mortalityMultivariable adjustmentUnadjusted analysesNational registryInfarctionWhite womenAspirinAngiographyTherapyWhite menSexPatientsBlack womenSex differencesParticular treatmentBlack menWomenDeathRelationship Between Time of Day, Day of Week, Timeliness of Reperfusion, and In-Hospital Mortality for Patients With Acute ST-Segment Elevation Myocardial Infarction
Magid DJ, Wang Y, Herrin J, McNamara RL, Bradley EH, Curtis JP, Pollack CV, French WJ, Blaney ME, Krumholz HM. Relationship Between Time of Day, Day of Week, Timeliness of Reperfusion, and In-Hospital Mortality for Patients With Acute ST-Segment Elevation Myocardial Infarction. JAMA 2005, 294: 803-812. PMID: 16106005, DOI: 10.1001/jama.294.7.803.Peer-Reviewed Original ResearchMeSH KeywordsAdultAfter-Hours CareAgedAged, 80 and overAngioplasty, Balloon, CoronaryBenchmarkingChronology as TopicFemaleHospital MortalityHospitalsHumansMaleMiddle AgedMyocardial InfarctionMyocardial ReperfusionRegistriesRetrospective StudiesThrombolytic TherapyTime and Motion StudiesTime FactorsUnited StatesUtilization ReviewConceptsST-segment elevation myocardial infarctionPercutaneous coronary interventionElevation myocardial infarctionBalloon timeFibrinolytic therapyHospital mortalityMyocardial infarctionAcute ST-segment elevation myocardial infarctionDrug timeRegular hoursTimeliness of reperfusionIn-Hospital MortalityDay of weekPCI patientsReperfusion therapyCohort studyCoronary interventionMean doorHospital characteristicsCatheterization laboratoryBetter outcomesPatientsHospital subgroupsTherapyPatient arrivalRacial differences in reperfusion therapy use in patients hospitalized with myocardial infarction: A regional phenomenon
Rathore SS, Frederick PD, Every NR, Barron HV, Krumholz HM. Racial differences in reperfusion therapy use in patients hospitalized with myocardial infarction: A regional phenomenon. American Heart Journal 2005, 149: 1074-1081. PMID: 15976791, PMCID: PMC2790272, DOI: 10.1016/j.ahj.2004.08.018.Peer-Reviewed Original ResearchConceptsTherapy useMyocardial infarctionBlack patientsReperfusion therapyWhite patientsRacial differencesLower crude ratesMyocardial Infarction 2Reperfusion therapy ratesCohort of patientsTherapy ratesMultivariable adjustmentClinical contraindicationsNational registryPractice patternsCrude ratePatientsInfarctionGeographic regionsTherapyLower ratesTreatmentNational patternsContraindicationsDifferences