Slide 1

Overview of NCHS Linked Data and Analytic Considerations

Hannah R. Day, PhD

11ObjectivesOverview of linked data resources Some analytic considerations of the linked dataMotivating ExampleCompare self-report diabetes in NHIS 2005 with 2005 Medicare claims for diabetes in the Chronic Condition (CC) Summary File. 23

NCHS Population Health SurveysLinked data files enable researchers to examine the factors that influence disability, chronic disease, health care utilization, morbidity, and mortality.NCHS currently links several surveys with Mortality data Medicare Enrollment and Claims Data (CMS)Medicaid/CHIP Enrollment and Claims data (CMS)Medicare Social Security Benefit History data (SSA) More information on our website:http://www.cdc.gov/nchs/data_access/data_linkage_activities.htm

3Surveys with Linked Administrative DataSurveyNHISNational Health Interview SurveyNHANESContinuous National Health and Nutrition Examination SurveyNHANES IIIThird National Health and Nutrition Examination SurveyNHANES IISecond National Health and Nutrition Examination SurveyNHEFSNHANES I Epidemiologic Followup StudyLSOA IISecond Longitudinal Studies of AgingNNHSNational Nursing Home Surveys44Linked Data ConsiderationsDefining Study SampleTiming of survey data and administrative claimsMortalityProgram ineligible Data IssuesEver Variable in Chronic Condition (CC) Summary FileMedicare Part CIncomplete LinkageLinkage ineligible ReweightingChild Survey Participants 5Linked Data ConsiderationsDefining Study SampleTiming of survey data and administrative claimsMortalityProgram ineligible Data IssuesEver Variable in Chronic Condition (CC) Summary FileMedicare Part CIncomplete LinkageLinkage ineligible ReweightingChild Survey Participants 67

National Health Interview Survey (NHIS) Linked data files enable researchers to examine the factors that influence disability, chronic disease, health care utilization, morbidity, and mortality.NCHS currently links several surveys with Mortality data Medicare Enrollment and Claims Data (CMS)Medicaid/CHIP Enrollment and Claims data (CMS)Medicare Social Security Benefit History data (SSA) More information on our website:http://www.cdc.gov/nchs/data_access/data_linkage_activities.htm

7Linked Data ConsiderationsDefining Study SampleTiming of survey data and administrative claimsMortalityProgram ineligible Data IssuesEver Variable in Chronic Condition (CC) Summary FileMedicare Part CIncomplete LinkageLinkage ineligible ReweightingChild Survey Participants 89Years of NHIS linked to Medicare:

199419951996199719981999200020012002200320042005Years of Medicare Data: 19911992199319941995199619971998199920002001200220032004200520062007Coming Soon: 20082009Years of NHIS-Medicare linkageCould consider excluding those with Mortality, but our current Mortality linkage does not include NHIS 2005.

910Years of NHIS linked to Medicare:

199419951996199719981999200020012002200320042005Years of Medicare Data: 19911992199319941995199619971998199920002001200220032004200520062007Coming Soon: 20082009Years of NHIS-Medicare linkageCould consider excluding those with Mortality, but our current Mortality linkage does not include NHIS 2005.

10Linked Data ConsiderationsDefining Study SampleTiming of survey data and administrative claimsMortalityProgram ineligible Data IssuesEver Variable in Chronic Condition (CC) Summary FileMedicare Part CIncomplete LinkageLinkage ineligible ReweightingChild Survey Participants 1112Years of NHIS linked to Medicare:

199419951996199719981999200020012002200320042005Years of Medicare Data: 19911992199319941995199619971998199920002001200220032004200520062007Coming Soon: 20082009Years of NHIS-Medicare linkageYears of NHIS linked to Mortality through 2006

19941995199619971998199920002001200220032004Could consider excluding those with Mortality, but our current Mortality linkage does not include NHIS 2005.

12Linked Data ConsiderationsDefining Study SampleTiming of survey data and administrative claimsMortalityProgram ineligible Data IssuesEver Variable in Chronic Condition (CC) Summary FileMedicare Part CIncomplete LinkageLinkage ineligibilityReweightingChild Survey Participants 13Medicare Program EligibilityNot everyone is eligible for Medicare 10 years Medicare-covered employment and age >=65