Surveillance of Mortality and Morbidity in U.S. Workers

University of Miami Study Database Documentation
 

For the purposes of this Study, the Investigators have made a series of policy decisions with regards to definitions, statistical analyses and other issues. In addition, in the process of their explorations of the NHIS database, the Investigators have encountered particular issues (e.g. “SOC” coding) which are detailed below in hopes that this will aid other investigators. Several of these explorations have resulted in detailed tabular data which have also been made available to other investigators where indicated in the documentation below. Of note, this is an ongoing study and exploration, as such this Study Documentation will continue to be updated as necessary. The following issues have been addressed:

 

 

 

 

Time Period

  • 1986-1994 since these were the years with mortality follow up available through 1997 (as of 2003).

 

 

NHIS Working Population

  • "Currently employed" (paid and unpaid) within last 2 weeks prior to annual NHIS interview (Kaminski and Spirtas 1980)

  • 18 yrs of age or older at time of annual NHIS interview

 

 

Use of Supplement Survey Data

  • Use only from the same year as their NHIS Survey

  • Do not use any supplements involving < 18 year olds

  • Weights for supplemental data

    1. use supplemental survey weight if doing prevalence/incidence

    2. use NHIS annual survey weight for all other uses (for example if used as a covariate)

 

  • If there is a year with > 2 or more supplements and overlap of participants, then

    1. for Prevalence estimates, use only the larger Supplement and its weights

    2. for smoking enrichment, use both supplements but IF discordance, use the data from the larger Supplement

    • ex: 1991, use Health Promotions Supplement for Prevalence with appropriate supplement weight; for smoking enrichment, use both Health Promotions and Smoking Supplements with annual NHIS survey weight, if discordance of smoking information, use Health Promotions smoking information

 

  • For years with > 2 or more supplements and no overlap and equal selection criteria, then use both supplements with appropriate supplement weight divided by the number of supplements

    • ex: 1987 Cancer Control and Cancer Epidemiology Supplements were mutually exclusive and used similar selection criteria

  • Eliminate 1989 Diabetes and 1988 TAPS supplements due to very little data and/or too selective

 

 

Occupation

              Label/indicate if >30% SE (as per Brackbill R 1988)

 

 

"SOC" Codes

 

 

Longest held job

 

 

Industry

  • Defined as current work in past 2 weeks prior to NHIS interview

  • "SIC" codes available but really US Census industry codes and are mislabeled as "SIC" by NHIS documentation

 

 

Smoking/Tobacco Use

  • Create additional variable for all NHIS employed participants

  • NHIS Questions: Have you smoked 100 > cigarettes in your life?. What is your current smoking status?

          These two questions were asked of a subset of adults in the following years: 1987, 1989, 1990, 1991, 1992, 1993, 1994.

  • Variable created for all NHIS participants:Keep Historic Smokers (ie known smoked > 100 cigs but not if current or former) as "Unknown or Missing" These people can be used if using: Ever vs Smokers but not if any detail on the smokers (then must set to "missing")

    • Therefore Smoking Categories: Never, Ever (Former, Current), Unknown

  • No smoking questions from the 1994 second supplement on aging and the 1994 followback survey

 

 

Ethanol Use

  • Only use as supplemental check

    • • 1988 Alcohol Supplement (43,809 subjects)

      • o Variable: Current Drinkers” = people who answered “yes” to “in the past 12 months the subject has had at least 12 drinks of any kind of alcoholic beverages.” (Question 1b)

    • • 1991 Alcohol and Drug Supplement (21,174 subjects)    

      • o Variable Current Drinker =people who drank alcohol in the past 12 months (ie. Answered yes to tape location 337-338, item number 2, items and codes 01-12 (1-12 months drank).

 

 

Response to NHIS

  • In the period 1986-1994, a nnual NHIS household survey response rates ranged from 94% to 97% (1-9) ; annual response rates to the 1997-2002 adult core ranged from 70% (in 1999) to 80% (in 1997) (10-15).

 

REFERENCES

  1. Dawson DA, Adams PF. Current estimates from the National Health Interview Survey, 1986. Vital Health Stat 10 1987:1-177.

  2. Schoenborn CA, Marano M. Current estimates from the National Health Interview Survey, 1987. Vital Health Stat 10 1988:1-233.

  3. NCHS. Current estimates from the National Health Interview Survey, 1988. Vital Health Stat 10 1989:1-250.

  4. Adams PF, Benson V. Current estimates from the National Health interview survey, 1989. Vital Health Stat 10 1990:1-221.

  5. Adams PF, Benson V. Current estimates from the National Health Interview Survey, 1990. Vital Health Stat 10 1991:1-212.

  6. Adams PF, Benson V. Current estimates from the National Health Interview Survey, 1991. Vital Health Stat 10 1992:1-232.

  7. Benson V, Marano MA. Current estimates from the National Health Interview Survey, 1992. Vital Health Stat 10 1994:1-269.

  8. NCHS. Current estimates from the National Health Interview Survey, 1993. Vital Health Stat 10 1994:1-221.

  9. Adams PF, Marano MA. Current estimates from the National Health Interview Survey, 1994. Vital Health Stat 10 1995:1-520.

  10. Blackwell DL, Collins JG, Coles R. Summary health statistics for U.S. adults: National Health Interview Survey, 1997. Vital Health Stat 2002;10(205):1-110.

  11. Pleis JR, Coles R. Summary health statistics for U.S. adults: National Health Interview Survey, 1998. Vital Health Stat 2002;10(209):1-121.

  12. Pleis JR, Coles R. Summary health statistics for U.S. adults: National Health Interview Survey, 1999. Vital Health Stat 2003;10(212):1-145.

  13. Pleis JR, Benson V, Schiller JS. Summary health statistics for U.S. adults: National Health Interview Survey, 2000. Vital Health Stat 2003;10(215):1-141.

  14. Lucas JW, Schiller JS, Benson V. Summary health statistics for U.S. adults: National Health Interview Survey, 2001. Vital Health Stat 2004;10(218):1-143.

  15. Lethbridge-Cejku M, Schiller JS, Bernadel L. Summary health statistics for U.S. adults: National Health Interview Survey, 2002. Vital Health Stat 2004;10(222):1-160.

 

 

Proxy

  • Since only one household member used for the NHIS interviews (and often for the supplements), proxy information is provided for a large component

  • Always re-look at analyses using proxy as an interaction term

 

 

Vital Status

  • Use NHIS algorithm criteria for matching with National Death Index

  • Keep proxy deaths

  • Make first day of each quarter the arbitrary date of death

  • Eliminate any deaths that occurred prior to date of NHIS interview although keep these individuals in the dataset but will list as "missing" data

  • Assume if not dead then alive

 

 

Comparison Population

  • 2000 US Census

  • 2000 US Mortality rates

 

 

Education

  • Variable categorical defined as <12 grade, 12 grade, > 12 grade

  • Approximately 4000 missing data kept in analysis except for education

 

 

Age

  • Variable continuous

  • Variable categorical defined as: 18-44, 45-64, 65+ years

 

 

Race Ethnicity

  • Variable categorical defined as: White Non-Hispanic, White Hispanic, Black Non-Hispanic, All Others

 

 

Sample Size Considerations

  • NHIS default of >30% of the Relative Standard Error (RSE) gets and asterix to indicate that the data are unstable• Do not use data with less than 45 individuals/yr

 

 

Statistical Analyses

  • Mortality

    • O/E

    • Cox

    • Standardized Mortality Ratios (SMRs)

      • The Investigators have provided SAS program language to perform the SMR calculations. In addition, Noble, Drever, and Shah give details on computing confidence intervals, with formulas for events > 100 and table values for events between 0 and 100 

  • Morbidity

    • Logistic Regression

    • Trend

 

 

Obesity/Height & Weight Measurement

  • In 1996 the National Center for Health Statistics (NCHS) truncated the range of weight from   50-500 pounds to 98-289 pounds and height from 36-98 inches to 59-76 inches in order to protect possible identification of survey participants.

  • For the 1996 NHIS participants outside of the abovementioned ranges, Body Mass Index (BMI) cannot be calculated.

  • Beginning in 1997, the NCHS computed BMI values for all survey participants, including those outside of the restricted range.

 

 

Acute & Chronic Disability Study Definitions

Study Variable Definition

Acute Disability 

AFD1 = 0 vs ≥ 1 Restricted Activity Days in Prior 2 Wks
AFD2 = 0 vs ≥ 1 Bed Days in Prior 2 Wks
AFD3 = 0 vs ≥ 1 Lost Work Days in Prior 2 Wks


Chronic Disability 

 
CFD1 = 0-3 vs ≥ 4 Doctor Visits in Prior 12 months
CFD2 = 0 vs ≥ 1 Hospitalizations in Prior 12 months

Health Status 

 
HS1 = 0 if Health Self-rated Excellent or Good;
       = 1 if Health Self-rated Fair or Poor
HS2 = 0 vs ≥ 1 Health Condition reported

1986 - 1994 NHIS Chronic Condition Prevalence
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

© 2018 by MORG Staff. 

The MORG is a NIOSH-funded (R01-OH003915) research team in the Department of Public Health Sciences, at the University of Miami, Miller School of Medicine.

Last Updated:   July 27, 2018

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Tel: 305-243-6980

Fax: 305-243-5544

Email: dlee@med.miami.edu

 

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