Codes and Frequencies
For persons age 18+ included in the NHIS during survey years 1986 to 2014 who provided sufficient data for linking (MORTELIG), MORTSTAT reports the final vital status (assumed alive or assumed deceased). This status was determined by NCHS based on probabilistic matches of survey participants' NHIS records to National Death Index (NDI) records.
For further information on the NDI and the creation of the mortality variables, see the variable description for MORTELIG and the technical documents from NCHS on the creation and analysis of the NHIS Linked Mortality Files.
Because adult survey participants who provided insufficient data for linking may differ from those who provided enough data for linking, ignoring the ineligible adult respondents (IPUMS NHIS code 3 in MORTELIG) could lead to biased mortality analysis. To correct this bias, NCHS developed eligibility-adjusted weights: MORTWT, available for 1986-2014, for use with variables from the NHIS person files, and MORTWTSA, available for 1997-2014, for use with variables from the sample adult files. When analyzing NHIS variables from the person files in conjunction with mortality variables, users should employ MORTWT (rather than the standard person weight, PERWEIGHT). When analyzing variables from the sample adult files in conjunction with mortality variables, users should employ MORTWTSA (rather than the standard sample weight, SAMPWEIGHT).
The other mortality variables included in IPUMS NHIS are the following:
- MORTDODY (Year of death)
- MORTDODQ (Quarter of death)
- MORTUCOD (Underlying cause of death)
- MORTUCODLD (Leading underlying cause of death)
- MORTDIAB (Multiple cause of death flag, diabetes as a contributing factor)
- MORTHIPFX (Multiple cause of death flag, hip fracture as a contributing factor)
- MORTHYPR (Multiple cause of death flag, hypertension as a contributing factor)
- MORTCMS (Mortality status obtained from Centers for Medicaid and Medicare Services)
- MORTNDI (Mortality match with National Death Index)
- MORTSSA (Mortality status obtained from Social Security Administration)
- 1986-2014: All persons age 18+ eligible for mortality follow-up.
- 1986-2014 : MORTWT