2024
How to Use Quasi-Experimental Methods in Cardiovascular Research: A Review of Current Practice
Carter A, Jayawardana S, Costa-Font J, Nasir K, Krumholz H, Mossialos E. How to Use Quasi-Experimental Methods in Cardiovascular Research: A Review of Current Practice. Circulation Cardiovascular Quality And Outcomes 2024, 17: e010078. PMID: 38362765, DOI: 10.1161/circoutcomes.123.010078.Peer-Reviewed Original ResearchConceptsRandomized controlled trialsDecision aidJoanna Briggs Institute checklistControlled trialsQuasi-experimental methodObservational studyInterrupted time series analysisQuasi-experimental studyDifference-in-differences analysisEstimate causal relationshipsSystematic search strategyInstrumental variable analysisQuality appraisalInstitute checklistInclusion criteriaGraphical decision aidReview of current practicesCurrent practicesRandom assignmentSearch strategyHigh-impact articlesVariability analysisTime series analysisCardiovascular researchAIDS
2020
Quality of informed consent documents among US. hospitals: a cross-sectional study
Spatz ES, Bao H, Herrin J, Desai V, Ramanan S, Lines L, Dendy R, Bernheim SM, Krumholz HM, Lin Z, Suter LG. Quality of informed consent documents among US. hospitals: a cross-sectional study. BMJ Open 2020, 10: e033299. PMID: 32434934, PMCID: PMC7247389, DOI: 10.1136/bmjopen-2019-033299.Peer-Reviewed Original ResearchConceptsInformed consent documentsHOSPITAL scoreUS hospitalsMean hospital scoresRetrospective observational studyConsent documentsCross-sectional studyEight-item instrumentService patientsElective proceduresProcedure typeObservational studySurgical proceduresMedicare feeHospitalHospital qualityMeasure scoresInformed consentMost hospitalsSpearman correlationScoresFace validityIndependent ratersOutcomesStakeholder feedbackUse 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
2017
Inferior Vena Cava Filters to Prevent Pulmonary Embolism Systematic Review and Meta-Analysis
Bikdeli B, Chatterjee S, Desai NR, Kirtane AJ, Desai MM, Bracken MB, Spencer FA, Monreal M, Goldhaber SZ, Krumholz HM. Inferior Vena Cava Filters to Prevent Pulmonary Embolism Systematic Review and Meta-Analysis. Journal Of The American College Of Cardiology 2017, 70: 1587-1597. PMID: 28935036, PMCID: PMC8412839, DOI: 10.1016/j.jacc.2017.07.775.Peer-Reviewed Original ResearchConceptsDeep vein thrombosisSubsequent pulmonary embolismInferior vena cava filterPulmonary embolismVena cava filtersIVC filtersCause mortalityOdds ratioCava filtersSystematic reviewSubsequent deep vein thrombosisInverse variance fixed-effect modelRisk of PECochrane Central RegisterQuality of evidenceFixed-effects modelCentral RegisterVein thrombosisControlled TrialsOverall mortalityObservational studyMAIN OUTCOMEPrimary analysisMeta-AnalysisMortality
2016
Gender differences in physical activity following acute myocardial infarction in adults: A prospective, observational study
Minges KE, Strait KM, Owen N, Dunstan DW, Camhi SM, Lichtman J, Geda M, Dreyer RP, Bueno H, Beltrame JF, Curtis JP, Krumholz HM. Gender differences in physical activity following acute myocardial infarction in adults: A prospective, observational study. European Journal Of Preventive Cardiology 2016, 24: 192-203. PMID: 27885060, DOI: 10.1177/2047487316679905.Peer-Reviewed Original ResearchMeSH KeywordsAdolescentAdultAustraliaCardiac RehabilitationChi-Square DistributionExerciseExercise TherapyFemaleHealth BehaviorHealth Knowledge, Attitudes, PracticeHumansMaleMiddle AgedMyocardial InfarctionOdds RatioPatient ComplianceProspective StudiesRisk FactorsSex FactorsSpainTime FactorsTreatment OutcomeUnited StatesYoung AdultConceptsAcute myocardial infarctionPost-acute myocardial infarctionMyocardial infarctionPhysical activityRegular physical activity participationYoung AMI Patients (VIRGO) studyPhysical activity recommendationsAmerican Heart AssociationPhysical activity trajectoriesNon-white raceMyocardial infarction recoveryPhysical activity participationGender differencesHospital dischargeHeart AssociationLifestyle behaviorsActivity recommendationsObservational studyInfarctionAustralian hospitalsTargeted interventionsOne monthPatientsTime pointsLonger durationCoronary Catheterization and Percutaneous Coronary Intervention in China: 10-Year Results From the China PEACE-Retrospective CathPCI Study
Zheng X, Curtis JP, Hu S, Wang Y, Yang Y, Masoudi FA, Spertus JA, Li X, Li J, Dharmarajan K, Downing NS, Krumholz HM, Jiang L. Coronary Catheterization and Percutaneous Coronary Intervention in China: 10-Year Results From the China PEACE-Retrospective CathPCI Study. JAMA Internal Medicine 2016, 176: 512. PMID: 26974883, PMCID: PMC5459379, DOI: 10.1001/jamainternmed.2016.0166.Peer-Reviewed Original ResearchMeSH KeywordsAgedAged, 80 and overAngina, UnstableCardiac CatheterizationChinaCoronary Artery DiseaseDrug-Eluting StentsFemaleHospital MortalityHospitals, UrbanHumansLength of StayMaleMedical RecordsMiddle AgedMyocardial InfarctionOdds RatioOutcome Assessment, Health CarePercutaneous Coronary InterventionPostoperative ComplicationsPostoperative HemorrhageQuality of Health CareRetrospective StudiesStentsTime-to-TreatmentConceptsPercutaneous coronary interventionDrug-eluting stentsQuality of careCoronary catheterizationCoronary interventionNonobstructive coronary artery diseasePrimary percutaneous coronary interventionFuture quality improvement initiativesEvidence-based medicationsOutcomes of patientsCoronary artery diseaseClinical observational studyUse of catheterizationQuality improvement initiativesCalendar year 2001Hospital mortalityArtery diseasePatient characteristicsStable patientsTreatment patternsMedian lengthMean agePCI proceduresMedical recordsObservational study
2012
Duration of resuscitation efforts and survival after in-hospital cardiac arrest: an observational study
Goldberger ZD, Chan PS, Berg RA, Kronick SL, Cooke CR, Lu M, Banerjee M, Hayward RA, Krumholz HM, Nallamothu BK, Investigators F. Duration of resuscitation efforts and survival after in-hospital cardiac arrest: an observational study. The Lancet 2012, 380: 1473-1481. PMID: 22958912, PMCID: PMC3535188, DOI: 10.1016/s0140-6736(12)60862-9.Peer-Reviewed Original ResearchConceptsHospital cardiac arrestSpontaneous circulationCardiac arrestResuscitation attemptsMedian durationResuscitation effortsGuidelines-Resuscitation registryDuration of resuscitationRisk-adjusted survivalHigh-risk populationAmerican Heart AssociationPrimary endpointHospital dischargeHeart AssociationObservational studyPatientsUS hospitalsClinical Scholars ProgramSurvival rateHospitalResuscitationHigher survival rateSurvivalNational InstituteHigher likelihoodPatterns and Loss of Sexual Activity in the Year Following Hospitalization for Acute Myocardial Infarction (a United States National Multisite Observational Study)
Lindau ST, Abramsohn E, Gosch K, Wroblewski K, Spatz ES, Chan PS, Spertus J, Krumholz HM. Patterns and Loss of Sexual Activity in the Year Following Hospitalization for Acute Myocardial Infarction (a United States National Multisite Observational Study). The American Journal Of Cardiology 2012, 109: 1439-1444. PMID: 22546209, PMCID: PMC3341956, DOI: 10.1016/j.amjcard.2012.01.355.Peer-Reviewed Original ResearchConceptsAcute myocardial infarctionActivity 1 yearSexual activityMyocardial infarctionMain outcome measurementsActivity-related outcomesThird of womenMultivariable hierarchical modelsHospital discharge instructionsLack of counselingMultisite observational studyCorrelates of lossTRIUMPH registryPhysician counselingDischarge counselingYear mortalityDischarge instructionsMean ageObservational studyOutcome measurementsHospitalizationFirst monthPatientsMortalityInfarctionComparison of hospital risk-standardized mortality rates calculated by using in-hospital and 30-day models: an observational study with implications for hospital profiling.
Drye EE, Normand SL, Wang Y, Ross JS, Schreiner GC, Han L, Rapp M, Krumholz HM. Comparison of hospital risk-standardized mortality rates calculated by using in-hospital and 30-day models: an observational study with implications for hospital profiling. Annals Of Internal Medicine 2012, 156: 19-26. PMID: 22213491, PMCID: PMC3319769, DOI: 10.7326/0003-4819-156-1-201201030-00004.Peer-Reviewed Original ResearchConceptsRisk-standardized mortality ratesAcute myocardial infarctionHospital risk-standardized mortality ratesHospital mortality measuresHeart failureMortality rateObservational studyNonfederal acute care hospitalsMortality measuresAcute care hospitalsMean LOSPrimary outcomeStandardized followCare hospitalBlood InstituteService patientsMyocardial infarctionNational HeartPatient LOSMedicare feePneumoniaHospitalAdmissionHospital qualityHospital profiling
2011
Operator Experience and Carotid Stenting Outcomes in Medicare Beneficiaries
Nallamothu BK, Gurm HS, Ting HH, Goodney PP, Rogers MA, Curtis JP, Dimick JB, Bates ER, Krumholz HM, Birkmeyer JD. Operator Experience and Carotid Stenting Outcomes in Medicare Beneficiaries. JAMA 2011, 306: 1338-1343. PMID: 21954477, PMCID: PMC3208144, DOI: 10.1001/jama.2011.1357.Peer-Reviewed Original ResearchMeSH KeywordsAge FactorsAgedAged, 80 and overAtherosclerosisCarotid StenosisCenters for Medicare and Medicaid Services, U.S.Clinical CompetenceFee-for-Service PlansFemaleHospital MortalityHumansInsurance CoverageMaleMedicarePhysiciansQuality of Health CareRetrospective StudiesStentsStrokeTime FactorsTreatment OutcomeUnited StatesConceptsAnnual operator volumeCarotid stentingOperator volumeMedicare beneficiariesNational coverage decisionHigh riskOperator experienceStudy periodThirty-day mortalityEmbolic protection devicesHigh-volume operatorsLow-volume operatorsService Medicare beneficiariesLow annual volumeMultivariable adjustmentOlder patientsRate of failureClinical trialsCoverage decisionsObservational studyMAIN OUTCOMEPatientsClinical practiceStentingMore procedures
2010
Variation in Recovery
Lichtman JH, Lorenze NP, D'Onofrio G, Spertus JA, Lindau ST, Morgan TM, Herrin J, Bueno H, Mattera JA, Ridker PM, Krumholz HM. Variation in Recovery. Circulation Cardiovascular Quality And Outcomes 2010, 3: 684-693. PMID: 21081748, PMCID: PMC3064946, DOI: 10.1161/circoutcomes.109.928713.Peer-Reviewed Original ResearchConceptsAcute myocardial infarctionYoung AMI patientsAMI patientsYoung womenHeart diseaseSex differencesExcess mortality riskIschemic heart diseaseRisk stratification modelPsychosocial risk factorsYears of ageQuality of careComparison cohortPrognostic factorsPrognostic importanceAMI populationMyocardial infarctionRisk factorsObservational studyMortality riskHigh riskAMI eventsPatientsAge accountWomenTrends in Length of Stay and Short-term Outcomes Among Medicare Patients Hospitalized for Heart Failure, 1993-2006
Bueno H, Ross JS, Wang Y, Chen J, Vidán MT, Normand SL, Curtis JP, Drye EE, Lichtman JH, Keenan PS, Kosiborod M, Krumholz HM. Trends in Length of Stay and Short-term Outcomes Among Medicare Patients Hospitalized for Heart Failure, 1993-2006. JAMA 2010, 303: 2141-2147. PMID: 20516414, PMCID: PMC3020983, DOI: 10.1001/jama.2010.748.Peer-Reviewed Original ResearchConceptsLength of stayShort-term outcomesHeart failureReadmission ratesHospital mortalityDischarge dispositionRisk ratioThirty-day readmission ratesMortality risk ratioSkilled nursing facilitiesHome care servicesHospital stayOlder patientsUnadjusted analysesMedicare patientsObservational studyMedicare feeNursing facilitiesPatientsStayCare servicesMortalityMarked reductionMean lengthOutcomes
2009
Reduction in Acute Myocardial Infarction Mortality in the United States: Risk-Standardized Mortality Rates From 1995-2006
Krumholz HM, Wang Y, Chen J, Drye EE, Spertus JA, Ross JS, Curtis JP, Nallamothu BK, Lichtman JH, Havranek EP, Masoudi FA, Radford MJ, Han LF, Rapp MT, Straube BM, Normand SL. Reduction in Acute Myocardial Infarction Mortality in the United States: Risk-Standardized Mortality Rates From 1995-2006. JAMA 2009, 302: 767-773. PMID: 19690309, PMCID: PMC3349070, DOI: 10.1001/jama.2009.1178.Peer-Reviewed Original ResearchConceptsRisk-standardized mortality ratesAcute myocardial infarctionShort-term mortality rateMortality rateHospital variationNonfederal acute care hospitalsAcute myocardial infarction mortalityHospital mortality rateDay of admissionRisk standardized mortality ratesAcute care hospitalsMyocardial infarction mortalityHealth care professionalsIndex hospitalizationCare hospitalMyocardial infarctionNational averagePatient levelMedicare patientsObservational studyMedical adviceHospital varianceMAIN OUTCOMECare professionalsPatients
2007
Summary of Evidence Regarding Hospital Strategies to Reduce Door-to-Balloon Times for Patients With ST-Segment Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention
Bradley EH, Nallamothu BK, Curtis JP, Webster TR, Magid DJ, Granger CB, Moscucci M, Krumholz HM. Summary of Evidence Regarding Hospital Strategies to Reduce Door-to-Balloon Times for Patients With ST-Segment Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention. Critical Pathways In Cardiology A Journal Of Evidence-Based Medicine 2007, 6: 91-97. PMID: 17804968, DOI: 10.1097/hpc.0b013e31812da7bc.Peer-Reviewed Original ResearchConceptsST-segment elevation myocardial infarctionElevation myocardial infarctionPercutaneous coronary interventionBalloon timeCoronary interventionCross-sectional designMyocardial infarctionCatheterization laboratoryPrompt percutaneous coronary interventionPrimary percutaneous coronary interventionHospital-based strategiesEmergency medicine physiciansHospital strategiesSummary of evidenceRandomized trialsPrehospital electrocardiogramCatheterization teamObservational studyMedicine physiciansClinical importanceComputerized searchPatientsEffective interventionsHospitalHospital effortsSocioeconomic disparities in outcomes after acute myocardial infarction
Bernheim SM, Spertus JA, Reid KJ, Bradley EH, Desai RA, Peterson ED, Rathore SS, Normand SL, Jones PG, Rahimi A, Krumholz HM. Socioeconomic disparities in outcomes after acute myocardial infarction. American Heart Journal 2007, 153: 313-319. PMID: 17239695, DOI: 10.1016/j.ahj.2006.10.037.Peer-Reviewed Original ResearchConceptsAcute myocardial infarctionBaseline clinical statusClinical factorsQuality of careLow socioeconomic statusSocioeconomic statusClinical statusMyocardial infarctionMultivariable modelingWorse clinical statusEducation levelSelf-reported household incomeCause mortalityCause rehospitalizationHazard ratioCare measuresObservational studyHousehold incomeRehospitalizationHigh riskUS hospitalsHigh mortalityPatientsMortalitySocioeconomic disparities
2006
Hydroxymethylglutaryl‐CoA Reductase Inhibitors in Older Persons with Acute Myocardial Infarction: Evidence for an Age–Statin Interaction
Foody JM, Rathore SS, Galusha D, Masoudi FA, Havranek EP, Radford MJ, Krumholz HM. Hydroxymethylglutaryl‐CoA Reductase Inhibitors in Older Persons with Acute Myocardial Infarction: Evidence for an Age–Statin Interaction. Journal Of The American Geriatrics Society 2006, 54: 421-430. PMID: 16551308, PMCID: PMC2797316, DOI: 10.1111/j.1532-5415.2005.00635.x.Peer-Reviewed Original ResearchMeSH KeywordsAge FactorsAged, 80 and overAtorvastatinCholesterol, LDLDrug PrescriptionsFatty Acids, MonounsaturatedFemaleFluvastatinFollow-Up StudiesHeptanoic AcidsHumansHydroxymethylglutaryl-CoA Reductase InhibitorsIndolesLovastatinMaleMyocardial InfarctionOdds RatioPravastatinPyridinesPyrrolesRetrospective StudiesSurvival RateTreatment OutcomeConceptsAcute myocardial infarctionHydroxymethylglutaryl-CoA reductase inhibitorsStatin therapyMyocardial infarctionLower mortalityOlder personsReductase inhibitorsPrincipal discharge diagnosisAcute care hospitalsCause mortalityEligible patientsOlder patientsYounger patientsCare hospitalDischarge prescriptionsPrimary outcomeDischarge diagnosisHospital characteristicsEfficacy dataMedicare patientsMultivariable modelObservational studyPatientsStatinsDischarge statins
2005
Hospital Improvement in Time to Reperfusion in Patients With Acute Myocardial Infarction, 1999 to 2002
McNamara RL, Herrin J, Bradley EH, Portnay EL, Curtis JP, Wang Y, Magid DJ, Blaney M, Krumholz HM, Investigators N. Hospital Improvement in Time to Reperfusion in Patients With Acute Myocardial Infarction, 1999 to 2002. Journal Of The American College Of Cardiology 2005, 47: 45-51. PMID: 16386663, PMCID: PMC1475926, DOI: 10.1016/j.jacc.2005.04.071.Peer-Reviewed Original ResearchConceptsST-segment elevation myocardial infarctionBalloon timeMin/yearNeedle timeMyocardial infarctionHospital characteristicsAcute ST-segment elevation myocardial infarctionPercutaneous coronary intervention cohortPercutaneous coronary intervention volumeElevation myocardial infarctionPercutaneous coronary interventionRetrospective observational studyFour-year study periodRapid reperfusionCoronary interventionFibrinolytic therapyHospital arrivalTherapy cohortReperfusion timeIntervention cohortNational registryIntervention volumeObservational studyHospital improvementPatientsLow-to-Moderate Alcohol Intake and Health Status in Heart Failure Patients
Salisbury AC, House JA, Conard MW, Krumholz HM, Spertus JA. Low-to-Moderate Alcohol Intake and Health Status in Heart Failure Patients. Journal Of Cardiac Failure 2005, 11: 323-328. PMID: 15948080, DOI: 10.1016/j.cardfail.2004.11.009.Peer-Reviewed Original ResearchConceptsKansas City Cardiomyopathy QuestionnaireModerate alcohol intakeHealth statusHF hospitalizationAlcohol intakeAlcohol abstinenceBaseline Kansas City Cardiomyopathy QuestionnaireShort Form-12 scoresComplete alcohol abstinenceHeart failure guidelinesMulticenter observational studyHeart failure patientsModerate alcohol consumptionSF-12 scoresKCCQ scoresHF outpatientsHF patientsFailure patientsMultivariable analysisBaseline differencesObservational studyModerate drinkersAlcohol consumptionSimilar outcomesAlcohol useThiazolidinediones, Metformin, and Outcomes in Older Patients With Diabetes and Heart Failure
Masoudi FA, Inzucchi SE, Wang Y, Havranek EP, Foody JM, Krumholz HM. Thiazolidinediones, Metformin, and Outcomes in Older Patients With Diabetes and Heart Failure. Circulation 2005, 111: 583-590. PMID: 15699279, DOI: 10.1161/01.cir.0000154542.13412.b1.Peer-Reviewed Original ResearchConceptsHeart failureInsulin-sensitizing drugsOlder patientsLower riskCox proportional hazards modelAntidiabetic drug prescriptionRetrospective cohort studyPrincipal discharge diagnosisClustering of patientsProportional hazards modelCohort studySecondary outcomesPrimary outcomeMetformin treatmentRandomized trialsThiazolidinedione treatmentDischarge diagnosisInsulin sensitizersAdverse outcomesDrug prescriptionsMultivariable modelObservational studyHospital variablesThiazolidinedione classHigh riskThe generalizability of observational data to elderly patients was dependent on the research question in a systematic review
Gross CP, Garg PP, Krumholz HM. The generalizability of observational data to elderly patients was dependent on the research question in a systematic review. Journal Of Clinical Epidemiology 2005, 58: 130-137. PMID: 15680745, DOI: 10.1016/j.jclinepi.2004.10.001.Peer-Reviewed Original ResearchConceptsCooperative Cardiovascular ProjectIntracranial hemorrhageSystematic reviewBeta-blocker useElderly patientsAngiography useCommunity patientsAtrial fibrillationRisk factorsObservational studyOutcome measuresRCT dataPresentation delayGlobal UtilizationT-PAPatientsSimilar predictorsTreatment variationStudy questionsCCP dataGUSTOHemorrhageReviewFibrillationAbsolute rate