Kathryn Rose and J. Stephen Perhac University of North Carolina at Chapel Hill

1. Using Historical Records to Reconstruct Early Life SES Exposures in Decedents: Preliminary Findings from a Pilot Study Kathryn Rose and J. Stephen Perhac University of North Carolina at Chapel Hill

2. Background • Early life socioeconomic conditions associated with increased risk of chronic diseases in adulthood • In most ongoing epidemiologic studies early life SES not ascertained at study inception • Collect from study participants while study is ongoing • Obtain from historical records

3. Can Early Life SES Be Obtained From Historical Records? • Linkage of death certificates with 1900-1920 individual census records (Hill, 2000; Preston,1996) • Elderly, white men: 70% linkage • Elderly black men: 56% linkage • Study of link between childhood SES and Alzheimer’s disease (Moceri, 2001) • Attempted linkage with birth certificates and declassified 1910-20 census records • 86% of participants linked to birth certificates and/or census record • No significant variation by gender, age or education

4. Rationale for Current Pilot Study • Feasibility of using public records to obtain early life SES information: • Accessibility • Cost ($$$ and time) • Availability of parental SES data • Completeness • Comparability to data from other sources • What are the sociodemographic determinants of successful linkage?

5. Participants • Atherosclerosis Risk in Communities (ARIC) Study • Baseline examination 1987-89 • Participants born between 1922 and 1944 • 451 participants from NC field center who subsequently died • Born between 1922-1935 (N=334) • Born in NC (N=319) or

6. Search Strategy Death Certificates SS-5s Database for searching records containing parental SES NC Born Born 1922-1935 Request NC Birth Certificates Search 1930 Census

7. Attempting Linkage to Records with Parental SES Information • Sources: • Death Certificates • Available for > 99% of decedents • Social Security application (SS-5) data • Obtained for 99% of decedents • Information abstracted: • Mother and father’s names • Participant data: • Name(s), date and place of birth, race, gender

8. Searching for NC Birth Certificates Death Certificates SS-5s Database for searching records containing parental SES N=451 NC Born N=319 Request NC Birth Certificates

9. NC Birth Certificate Search • 269 of 321 (84%) requested records found • Yield of usable records lower • (N=253 - 79%) • Yield: • Higher for whites than blacks (81% vs. 72%) • Higher for men than women (81% vs. 76%) • Did not not vary by education • 95% contained parental occupational data

10. Searching for 1930 Census Records Death Certificates SS-5s Database for searching records containing parental SES Born 1922-1935 N=334 Search 1930 Census

11. Linkage with 1930 Census Records • Accessed using a proprietary website with computerized index • Criteria Used to determine match: • Place of birth match vs. census address • Match on both parents’ names • Match on race • If participant born at the time of census • Did age and name match?

12. Linkage with 1930 Census Records • 238 of 334 records (71%) found on initial searches • Yield: • Higher for whites (74%) than blacks (57%) • Higher for men (73%) than women (68%) • Lower for those with less than HS education (69%) than for those with 12+ years of education (72%) • Highest between 1927 and 1931 (80% +)

13. Sociodemographic Information Available from 1930 Census Records • Virtually complete and legible • Socioeconomic information • Home ownership • Household size • Literacy of mother and father • Occupational data on parents • Job title • Industry • Whether an owner or an employee • Current employment status

14. Summary: Data Linkage NC Born N=319 Born 1922-1935 N=334 269 Birth Certificates Obtained (84%) 238 Census Records Located (74%) • Search on 382 decedent records • 9% not located • 91% birth certificate and / or census record

15. NC Born N=319 Born 1922-1935 N=334 182 decedents searched on both sources • 79% both birth certificate and census record • 19% census record only • 1% birth certificate only • 1% no birth certificate or census record

16. Strengths Data collected directly from parents at time participant was born Records archived by state Limitations Limited SES data Variation in content across time and place Access rules vary by state During this time period records not always filed at birth Costly Strengths and Limitations: Birth Certificate Data

17. Strengths Data collected in a standardized manner across U.S. by trained census takers Large amount of parental SES-related data Inexpensive Every person is indexed Limitations Records are hand-written Data abstraction is tedious Limited ability to track those not born in close proximity to census Only declassified after 72 years Strengths and Limitations: Census Data

18. Next Steps • Continued search of census records • Comparison of the parental occupational data from different sources • Census vs. birth certificate • 1920 vs. 1930 census • Historical records vs. those reported by participants

19. Conclusions • It is feasible to use birth certificates and early census records as a source of early life SES information • Accessible • Parental SES information is complete • Labor-intensive and potentially expensive • Potential use in such data is missing due to loss to follow-up

20. Acknowledgements • UNC at Chapel Hill Program on Demographics and Economics of Aging Research • Dr. Gerardo Heiss • The ARIC Study • B. Renee Ferguson • Brigitt Heier