Appendix Table 1.

Table of Studies of Children

Paper	Case, A. Lubotsky, D., and Paxson, C., 2002	Currie, J. and Stabile, M., 2003	Condliffe, S. and Link, C. R., 2008	Currie, A. Shields, M. A., and Price, E. 2007	Currie, J. Decker, S., and Lin, W., 2008	Murasko, J., 2008	Khanama, R., Nghiemb, H. S., and Connelly, L., 2009	Reinhold and Jurges, 2011
Motivation	Focus on children; sources of the gradient	Canada; Focus on recovery and quantity of shocks	US; Focus on recovery and quantity of shocks	England; Compare with US	Focus on public health insurance expansions	Health; cumulative vs. current income; panel	Australia; panel; explain gradient	Gernamy
Data	Maternal reported general health status of children (0–17)		US MEPS and PSID, 1996–2002	HSE (2–15)	US NHIS 1986–2005	US MEPS 1996–2005	LSAC 2 Cohorts	KiGGS 2003–2006 parental and medical interviews. Use general health and biomarkers.
Method	Ordered probit regression	Ordered probit regression and linear probability regression	Ordered probit regression and linear probability regression	Ordered probit regression and linear probability regression	Index of generosity of the state’s public health insurance programs as IV for individual Medicaid/SCHIP eligibility and conduct 2SLS	Ordered probit	Binary and ordered Probit models	Ordered probit.
Findings	Children’s health is positively related to family income at every age, and the slope of the gradient increases for older children	Depsite the universal health coverage, there exists an income gradient of children’s health that steepens during childhood. The gradient is likely due to higher rate of health shocks among low-income children.	In U.S., children in low income families are more likely than children in high income families to still suffer from chronic conditions present 5 years ago. Income gradient becomes steeper with age, partly because low income children are less able to recover from health shocks.	Although family income has a positive relationship with general health status, strength of the relationship is smaller than in US. Gradient does not increase with children’s age. No evidence of a significant income differential in porbability of a child having a chronic health condition.	More generous insurance coverage at early childhood is associated with better health at older ages (ages 9–17). In addition, the relationship between family income and children’s health has weakened for older children after the year the SCHIP initiated.	Replicate Case (2002) pattern though somewhat weaker. Increased persistence of health status among older children; stronger contemporaneous influence of income on adolescents.	Similar findings as US studies in that children from higher income families have better health but gradient flatter. No evidence of more health shocks or failure to respond to shocks by income. Some suggestion that health of mother part of explanation of the gradient.	Larger but flatter income gradient for subjective health. No evidence of a significant income differential in probablility of child having a chronic health condition but severity is less among higher income children.
Implications	Low family income on chilren’s health tend to accumulate during childhood. Thus, children from lower income families may suffer from both lower SES and poorer health when they transition into adulthood	Policies that focus only on reducing gaps in access to medical care may not be sufficient to reduce disparities in health.	Public policies that increase access to medical care for low income children could be useful in reducing the income gradient of children’s health.	Family income may not be a major determinant of children’s health in England. NHS may infuence. Challenged by Case, Lee, and Paxson that findings reflect miscoding of chronic conditions.	Assuring access to health care in early childhood may prevent the income gradient of children’s health from becoming steeper over time.	Since influence of SES cumulative, interventions at an earlier age may be most effective.	National health service can reduce gradient but not come close to eliminating it.	Low income creates a severeity effect among children but not an increase in the probability of health problems .