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From Health Research to Social Research: Privacy, Methods, Approaches . Leslie L Roos Distinguished Professor Department of Community Health Sciences Manitoba Centre For Health Policy.
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From Health Research to Social Research: Privacy, Methods, Approaches Leslie L Roos Distinguished ProfessorDepartment of Community Health SciencesManitoba Centre For Health Policy
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 For Comparison: Panel Study of Income Dynamics (PSID)
Hospital Medical Home Care Research Registry Nursing Home Pharmaceutical Provider Immunization Monitoring Vital Statistics Information-Rich Environment: Using Administrative Data Sleep Lab Clinical Data Alcoholism Panel Surveys Inflammatory Bowel Disease Database Educational and Social Data Cancer Registry National Population Health Survey Heart Health Survey Aging in Manitoba Study
Link files to incorporate new data sets while preserving privacy and confidentiality Measure such outcomes as educational achievement at population level Expanding Capabilities Moving from health research to social research involves preparatory work with databases, which must be organized to:
Use place of residence data (for any point in time) to calculate the number of moves, number of years in relatively poor neighborhoods, etc. 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. Expanding Capabilities (cont’d)
Respect for Privacy In Building Manitoba Database • 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
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 Linking while Preserving Privacy
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 Currently Available: Measures to Understand Well Being
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 Not Available
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 Small Area Measures from Statistics Canada
Obtaining indicators of socioeconomic risk for each small area Developing individual data on educational achievement Calculate rates of achievement based on small areas Track the entire population Combine census enumeration areas as appropriate (for quartiles or quintiles based on socioeconomic status of area of residence) Steps for comparing educational achievement across geographical areas parallel those developed for health research
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) Data Used
Population-Based Data Provide a Different Perspective
Grade 12 (S4) Performance, by Winnipeg SES Group, Language Arts Standards Test, 2001/02 18 year olds who should have written Pass/Fail rates of test writers
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 Estimating Family Circumstances
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 Other 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 Importance of Social Variables
Association between socioeconomic status and health may vary at different life stages Questions include: How do socioeconomic gradients evolve for both males and females as children grow older? What can we learn about gradient development by looking at the trajectories of individuals over time? Are socioeconomic gradients in child health changing over time? Emergence of the Socioeconomic Gradient
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) Problems with Non-Experimental Design
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
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 Literature Review
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 Approach One: Favourite Economist Tactic
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 Comparing Twin and Sibling Estimates
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. Results
1) Ordinary Least Squares (OLS) using entire sample OLS using sample of children with siblings Sibling sample including family fixed effects OLS using sample of twins Twin sample including family fixed effects *Looked at longer-term measures of child health and social outcomes Measuring Infant Health: Five Models*
Compare correlations for siblings and unrelated neighbours of similar ages 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 Approach Two:Sibling Neighbourhood Design
Urban-rural comparisons Socio-economic gradient (comparing means and correlations by income) Comparisons across dimensions of well being Study Opportunity Structures
Uses location of each family in a 6 digit postal code area Matches with neighbour in postal code area, then those ‘leftover’, with closest ‘leftover’ in census enumeration area (neat linear program) Sibling Neighbourhood Design
Sibling and Neighbour Correlations Girls Outside Winnipeg:1978-1987 Cohorts (excluding 1983)
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 A Guaranteed Annual Income Experiment
Did the elimination of income insecurity when children were particularly vulnerable affect their lives after the experiment ended? Will young children in families receiving assistance have experienced better health and social outcomes as adolescents? Research Questions
Anchored in a ‘place’ Feedback to ministries/data suppliers essential Deliverables negotiated “Smiling persistence” to obtain data sets Provincial Centres:
Have reviewed issues of measurement, data organization, and analytical strategy Expanded ability to examine outcomes through different stages in the life course From Health Research to Social Research