NHIS

 

 

The National Health Interview Survey (NHIS) is the largest and longest running household survey on health in the United States. The survey, which is conducted by the U.S. Census Bureau on behalf of the Centers for Disease Control and Prevention, covers a wide swath of health topics on the household and family, as well as a focal adult and child in each household.

UKCPR, in cooperation with the Economic Research Service (ERS) and the Food and Nutrition Service (FNS) in the U.S. Department of Agriculture, launched Understanding the Relationships between SNAP, Food Security, and Health in the National Health Interview Survey in 2015. The focus of this initiative was to provide rigorous research that utilized data from the National Health Interview Survey (NHIS) in order to expand our understanding of the effects of (1) the interaction between adult mental and physical health and household food insecurity, (2) SNAP on the health of both family caretaker and children, and (3) food insecurity on health and the possible mediating role of SNAP. This research was made possible with the addition of the Household Food Security Module to the NHIS beginning in 2011. Taking advantage of the expanding system of Federal Statistical Research Data Centers, all projects utilized restricted-access versions of the NHIS, and have accordingly went through an additional review process with the National Center for Health Statistics and/or the Agency for Health Care Research and Quality. Below are the discussion papers resulting from the research

2018

The effect of SNAP and the broader safety net on mental health and food insecurity

Previous literature documents a strong relationship between food insecurity and mental health, and also examines the impact of safety net programs on food insecurity.  However, little is known about the intersection between mental health, safety net participation, and food insecurity. In this research, we use a multi-program safety net calculator (including cash, food, and health insurance programs) and data from the National Health Interview Survey and the Current Population Survey to examine the effects of safety net generosity on food insecurity and mental health for single mother families.  We examine four research questions.  First, does state safety net generosity affect self-reported participation in safety net programs?  Second, does mental health affect participation in safety net programs, conditional on generosity?  Third, does more generous cash and food assistance affect mental health? And finally, how effective is the safety net in reducing food insecurity in the presence of mental health issues? We find that state-level safety net generosity does predict self-reported participation, and that conditional on generosity, those with mental health issues are significantly more likely to participate in safety net programs.  More generous cash and food assistance is protective of maternal mental health, but results are somewhat sensitive to the measure of mental health examined.  Finally, we find no effect of the safety net on 30-day food insecurity.  These results have important implications for the effectiveness of safety net programs for some of the most vulnerable members of society: low-income mothers suffering from mental health challenges and their children. 


Food security, health, and healthcare utilization: The role of SNAP for families in extreme poverty

We study whether SNAP mediates the effect of food insecurity on future health and healthcare utilization more for the extreme poor (i.e., those with income below 50% of the poverty line) than it mediates the effect for other low-income families (i.e., with incomes between 50% and 200% of the poverty line). We use data for about 23,000 people in the 2011-2012, 2012-2013, and 2013-2014 linked NHIS-MEPS surveys with the measures of food insecurity coming from the NHIS and the measures of SNAP benefits and various health outcomes from the MEPS. We find that SNAP significantly reduces the negative effects of food insecurity on several measures of health and healthcare-related outcomes for nonelderly adults, and that this reduction is often significantly greater for those in extreme poverty. However, we find no significant effects of this type for children. In addition, attempts to control for possible endogeneity of the SNAP effect of interest are unsuccessful because of a lack of strong instruments. Nevertheless, endogeneity of the effect of interest maybe biased downward, strengthening the support of the OLS estimates as valid.


Transition to adulthood: Dynamics of disability, food security, health, and SNAP participation

Young adults face enormous economic, social and psychological challenges when they transition into adulthood. This transition can be especially overwhelming and daunting for young adults with disabilities. Among the challenges young adults with disabilities are faced with are greater risk of low food security and barriers to healthcare. This study examines how the transition to adulthood may affect food security, health, and access to healthcare for youth with disabilities, and estimates the effects that SNAP has on this group in those turbulent years. Young adults face enormous economic, social and psychological challenges when they transition into adulthood. This transition can be especially overwhelming and daunting for young adults with disabilities. Among the challenges young adults with disabilities are faced with are greater risk of low food security and barriers to healthcare. This study examines how the transition to adulthood may affect food security, health, and access to healthcare for youth with disabilities, and estimates the effects that SNAP has on this group in those turbulent years.


2017

How well does SNAP protect families against the risk of food insecurity and poor health during economic downturns?

Our research project addressed the question of how well SNAP and the social safety net protects families against the risk of food insecurity and poor health during economic downturns. Previous research has documented the relationship between reductions in family incomes and food insufficiency and has examined the effects of resources that mitigate the effects of income volatility. The U.S. social safety net, including SNAP, exists to mitigate the deleterious effects of swings in family income, particularly among low- and moderate-income households. This work compares outcomes for lower income families and higher income families in response to economic downturns. To the extent that nutritional, food security and food-related health outcomes are unaffected by economic downturns, there is implicit evidence that the social safety net is working to protect economically disadvantaged families.


Using natural experiments to identify the effects of SNAP on child and adult health

The Supplemental Nutrition Assistance Program (SNAP; formerly known as food stamps) can have important impacts that extend beyond its intended aims to improve food security and nutrition, particularly for health and health care use. This project examined the impact of SNAP receipt and benefit level on the health of adults and children using two natural experiments to address selection bias: 1) state policy variation in SNAP in an instrumental variables (IV) analysis; and, 2) the temporary expansion of SNAP benefits and eligibility provided through the American Recovery and Reinvestment Act (ARRA) in a difference-in-difference (DD) approach. We used restricted data from the National Health Interview Survey (NHIS) from 2008 to 2014, restricting our sample to persons in SNAP-eligible and low-income SNAP-ineligible households. The IV analysis suggests that SNAP receipt is associated with improved health and reductions in foregone medical care due to affordability among adults and children. However, we find little evidence that ARRA’s temporary benefit increase led to any changes in health or health care use. Whereas SNAP receipt may improve health and health care use for populations close to the eligibility threshold (and thus induced to participate by some policies), the relatively small increase and reduction in SNAP benefits may not have been substantial enough to change health outcomes.


The real value of SNAP benefits and health outcomes

The food stamp program (SNAP) is one of the most important elements of the social safety net and is the second largest anti-poverty program for children in the U.S. (only the EITC raises more children above poverty). The program varies little across states and over time, which creates challenges for quasi-experimental evaluation. Notably, SNAP benefit levels are fixed across 48 states; but local food prices vary widely, leading to substantial variation in the real value of SNAP benefits. In this study, we leverage time variation in the real value of the SNAP benefit across markets to examine the effects of SNAP on child health. We link panel data on regional food prices and the cost of the Thrifty Food Plan, as measured by the USDA’s Quarterly Food at Home Price Database, to restricted-access geo-located National Health Interview Survey data on samples of SNAP-recipient and SNAP-eligible children. We estimate the relationship between the real value of SNAP benefits (i.e., the ratio of the SNAP maximum benefit to the TFP price faced by a household) and children’s health and health care utilization, in a fixed effects framework that controls for a number of individual-level and region characteristics, including non-food prices. Our findings indicate that children in market regions with a lower real value of SNAP benefits utilize significantly less health care, and may utilize emergency room care at increased rates. Lower real SNAP benefits also lead to an increase in school absences but we find no effect on reported health status.