1. From Health Research to Social Research: Privacy, Methods, Approaches Leslie L Roos Distinguished Professor Department of Community Health Sciences Manitoba Centre For Health Policy

2. For Comparison: Panel Study of Income Dynamics (PSID) Compare administrative data with the only social science study noted on “the NSF’s list of its fifty most significant projects in its fifty year history” Highlights issues in extending population- based (health) administrative data to facilitate social research

3. Information-Rich Environment: Using Administrative Data Research Registry Medical Vital Statistics Home Care Nursing Home Hospital Provider Pharmaceutical Immunization Monitoring Inflammatory Bowel Disease Database Sleep Lab Clinical Data Alcoholism Panel Surveys Cancer Registry Educational and Social Data Heart Health Survey Aging in Manitoba Study National Population Health Survey

7. Expanding Capabilities a)Link files to incorporate new data sets while preserving privacy and confidentiality b)Measure such outcomes as educational achievement at population level Moving from health research to social research involves preparatory work with databases, which must be organized to:

8. Expanding Capabilities (cont’d) c)Use place of residence data (for any point in time) to calculate the number of moves, number of years in relatively poor neighborhoods, etc. d)Estimating family composition at any point in time (tracking marital status, family size, ages of siblings and twins). Social variables used for more powerful research designs.

9. Canada Foundation for Innovation and provincially funded Data Laboratory Highest standards of security, privacy & confidentiality of data No names, no addresses Probabilistic record linkages across files as needed Data for research, not for administrative use Provincial privacy offices kept fully informed Respect for Privacy In Building Manitoba Database

10. Linking while Preserving Privacy Multi stage de-identification process: –Trustee preparation –Manitoba health links Trustee’s file to the encrypted PHIN –Crosswalk file provided to MCHP –Trustee provides data file –MCHP stores data separately and unlinked

11. Currently Available: Measures to Understand Well Being Available for population for one or more years: Age, grade level, school attendance, marks, achievement tests for Grade 3, Grade 9, Grade 12 Well-identified health conditions such as asthma and diabetes plus a measure of general health status can be studied through childhood and adolescence Healthcare utilization and costs Receipt of social assistance

12. Not Available Survey-based measure of household income and education are not available for entire population Manitoba comparisons of income measure found risk estimates for health status measures derived from neighborhood income not attenuated relative to those from household income May not be true everywhere

13. Small Area Measures from Statistics Canada Publicly available Use dissemination/enumeration areas Often encompass several six digit postal code areas Indicators such as mean household income and education, unemployment rates, etc. Canadian studies of the socioeconomic gradient in utilization often use small area markers

14. Steps for comparing educational achievement across geographical areas parallel those developed for health research 1)Obtaining indicators of socioeconomic risk for each small area 2)Developing individual data on educational achievement 3)Calculate rates of achievement based on small areas 4)Track the entire population 5)Combine census enumeration areas as appropriate (for quartiles or quintiles based on socioeconomic status of area of residence)

15. Data Used Up to nine years of Manitoba birth cohorts (1978-1987, excluding the 1983 cohort) Takes advantage of available provincial Grade 12 test scores About 13,000 in each cohort surviving and remaining in the province for the first 18 years of life Large sample for same-sex pairs (33,000) and multiple births (2,000)

16. Population-Based Data Provide a Different Perspective

17. Grade 12 (S4) Performance, by Winnipeg SES Group, Language Arts Standards Test, 2001/02 Pass/Fail rates of test writers 18 year olds who should have written

18. Estimating Family Circumstances Number of children in the family Birth order Mother’s marital status at birth of first child Age of mother at birth of first child Whether or not family was receiving income assistance Number of changes of residence

19. Other Social Variables Number of years in different types of families Number of “family structure” changes (parental separations, remarriages) Number of years living with disabled parent NOTE: Almost all variables can be measured at different points in time

20. Importance of Social Variables The first six social variables (i.e. number of children, birth order, etc.) were better predictors of educational achievement than survey model (includes household income and parental education) from PSID Predictive power varies with outcome selected (much lower for health outcomes) Used as control variables in sibling and sibling/neighbourhood research

21. Emergence of the Socioeconomic Gradient Association between socioeconomic status and health may vary at different life stages Questions include: 1) How do socioeconomic gradients evolve for both males and females as children grow older? 2) What can we learn about gradient development by looking at the trajectories of individuals over time? 3) Are socioeconomic gradients in child health changing over time?

22. Problems with Non-Experimental Design Analyzing casual relationship is difficult Omitted variables and measurement error are likely to bias the coefficients attached to measured variables Standard statistical analyses suffer from this problem (a growing literature in economics on this issue)

23. Whole population, sibling and twin studies each have different strengths and weaknesses Siblings and twin designs ‘control’ differently often using ‘family fixed effects’ statistical models Problems with Non-Experimental Design

24. Literature Review Relationship between birth weight and infant mortality decreases when differences between twins examined Twin samples help eliminate unobserved heterogeneity across families BUT twins generally of lower birth weight than singletons Gestational length not examined in twin studies Canadian data provide uniform access to health insurance whereas coverage in U.S. may vary even among siblings

25. Approach One: Favourite Economist Tactic Summarizing cross-family variation (each family as a separate condition) provides estimate of effects of presumably causal individual variables (such as birth weight) by differencing out family- specific characteristics affecting all children. Comparisons of siblings within families help make up for lack of control over variables measuring household income and parental education

26. Comparing Twin and Sibling Estimates Exploits benefits of both identification strategies Siblings provide a more representative sample but strategy risks biased estimates: A)Potential change in parental investment following the birth of first child B)Potential change in socioeconomic status between births Using twins eliminates these potential biases but sample is limited and unrepresentative Patterns of postnatal development (as a function of infant health) may differ for siblings and for twins h could affect results

27. Results Infant health strongly predicted both high school completion and income assistance take-up and length, controlling for a number of possible cofounders Long-term consequences of infant health were found across families, within siblings, and within twin pairs.

28. Measuring Infant Health: Five Models* 1)Ordinary Least Squares (OLS) using entire sample 2)OLS using sample of children with siblings 3)Sibling sample including family fixed effects 4)OLS using sample of twins 5)Twin sample including family fixed effects * Looked at longer-term measures of child health and social outcomes

29. Approach Two: Sibling Neighbourhood Design A)Compare correlations for siblings and unrelated neighbours of similar ages B)Use to identify an “upper bound on the influence of neighbourhoods, because neighbour correlations reflect similar family backgrounds as well as shared community backgrounds” C)Extend this approach to consider schoolmates and peers

30. Study Opportunity Structures Urban-rural comparisons Socio-economic gradient (comparing means and correlations by income) Comparisons across dimensions of well being

31. Sibling Neighbourhood Design Uses location of each family in a 6 digit postal code area Matches a)with neighbour in postal code area, then b)those ‘leftover’, with closest ‘leftover’ in census enumeration area (neat linear program)

32. Figure 1. Sibling - Neighbourhood Designs Neighbourhood A Family 1 Sibling 1a Sibling 1b Family 2 Sibling 2a Sibling 2b Neighbourhood B Family 3 Sibling 3a Sibling 3b Family 4 Sibling 4a Sibling 4b

33. Sibling and Neighbour Correlations Girls Outside Winnipeg: 1978-1987 Cohorts (excluding 1983) Pregnancy Before Age 19 Sibling (Unadjusted) Neighbour (Unadjusted) Neighbour (Adjusted).576*.368*.120* Income Assistance After Age 18 ( 1978-1982) Sibling (Unadjusted) Neighbour (Unadjusted) Neighbour (Adjusted).612*.174*.000* Held back by Grade 12 Sibling (Unadjusted) Neighbour (Unadjusted) Neighbour (Adjusted).675*.369*.111*

34. A Guaranteed Annual Income Experiment A population-based guaranteed annual income experiment in Dauphin, MB from 1974 to 1978 substantially reduced poverty. To study long-term effects: Propensity matching created a 3-to-1 control for all Dauphin and rural municipality residents. A second set of controls age-and sex-matched residents living in the test site before the experiment

35. Research Questions 1)Did the elimination of income insecurity when children were particularly vulnerable affect their lives after the experiment ended? 2)Will young children in families receiving assistance have experienced better health and social outcomes as adolescents?

36. Provincial Centres: 1)Anchored in a ‘place’ 2)Feedback to ministries/data suppliers essential 3)Deliverables negotiated 4)“Smiling persistence” to obtain data sets

37. From Health Research to Social Research 1)Have reviewed issues of measurement, data organization, and analytical strategy 2)Expanded ability to examine outcomes through different stages in the life course