Preventing HIV and STDs with Cash Transfers - Both Abroad and Here?

So on the heels of my post a few days ago comes a brand new study in The Lancet where women in Malawi randomized to receive unconditional cash transfers were less likely to contract HIV or other STDs than their unpaid counterparts. Here is a very nice summary piece on the study.

The mechanism linking cash transfers to reduced HIV may have something to do with the fact that women with access to such resources need not depend on men for the same. That is, women who are cash strapped or who lack opportunities in the labor market may need to depend on relationships where the partner can support them financially. Financial support, in turn, may reduce their ability to negotiate safe sex practices (this is the so-called "transactional sex").

Cash transfer programs of this nature may not just be useful overseas. A forthcoming article in the Journal of Adolescent Health shows that young African American women in Atlanta who have boyfriends who give them gifts are less likely to use condoms than those without such boyfriends or those with boyfriends who go on to find another source of spending money. The authors conclude that "receiving spending money from a boyfriend is common among adolescent women in populations targeted by pregnancy and sexually transmitted infection prevention interventions, and may undermine interventions' effectiveness." (HT: Paula C for the Atlanta paper).

Aspirations and Investing in Girls

Two great posts in Development Impact (my favorite economics blog right now) on aspirations, expected returns to investments, and the advancement of women. The first reviews evidence on how increased labor market opportunities available to women lead parents to invest more in the daughter's education. The second looks at how recent quotas decreeing that a randomly chosen 1/3 of village governance seats in India be filled by women have led to increased aspirations among girls and their parents, as well as increased investments in the former. In the study they cite, the gender gap in child education (which favors boys at baseline) was decimated when a village headship was randomly assigned to a woman.

The posts, and the articles cited there in, make two powerful points. First, information on opportunities for girls that may be unknown to families (for whom the cost of obtaining such information is high because of, say, lack of access to "plugged in" social networks, media, etc) can be powerful in combating gender bias. Second, proactively breaking down institutional barriers can play an important role, too, something we saw with the Civil Rights Movement here on our shores.

Preventing HIV By Paying People to Maintain Safe Sex Practices

Finding an HIV prevention strategy that works is one of the Holy Grail's of public health policy. Indeed, poor evidence of the epidemic quelling effects of most prevention programs (outside of biomedical interventions such as circumcision) have driven many to accept that treatment may actually be the best preventive device we have.

That may be true, but I do not think that all modes of prevention have been exhausted. One margin where there is some growing evidence is in providing cash transfers for people who maintain a given set of behaviors over a period of time. For example, one could pay people for every month they do not test positive for HIV. Such methods have been tried in the substance abuse world, apparently to good effect. Could it work with HIV/AIDS?

In a great new NBER working paper, Damien de Walque, William H. Dow, Carol Medlin, and Rose Nathan argue that the answer is a resounding yes (ungated version here). From the abstract:

[W]e discuss the use of sexual-behavior incentives in the Tanzanian RESPECT trial. There, participants who tested negative for sexually transmitted infections are eligible for outcome-based cash rewards. The trial was well-received in the communities, with high enrollment rates and over 90% of participants viewing the incentives favorably. After one year, 57% of enrollees in the “low-value” reward arm stated that the cash rewards “very much” motivated sexual behavioral change, rising to 79% in the “high-value” reward arm. Despite its controversial nature, we argue for further testing of such incentive-based approaches to encouraging reductions in risky sexual behavior.

The abstract undersells some of the evidence they cite in the paper, so I would go ahead and read the entire thing. While people may somehow find it reprehensible to pay people to do the right thing, there is already a great precedent in education and yearly doctor visits (i.e., conditional cash transfers for those things are all the rage in the Americas) as well as (as mentioned above) with getting people to stop using illicit/recreational drugs.

Health Expenditures in the US: Are We Not Spending Enough?

According the Elizabeth Bradley, a Professor of Health Policy and Administration at Yale, the answer is no. As she and Lauren Taylor point out in a recent New York Times editorial:

We studied 10 years’ worth of data and found that if you counted the combined investment in health care and social services, the United States no longer spent the most money — far from it. In 2005, for example, the United States devoted only 29 percent of gross domestic product to health and social services combined, while countries like Sweden, France, the Netherlands, Belgium and Denmark dedicated 33 percent to 38 percent of their G.D.P. to the combination. We came in 10th.

Bradley and Taylor put forth the argument that the things that make people healthy go beyond what we typically think of as health care. That is, access to employment, good housing, food security, and educational institutions all contribute to population health. I don't think this is a revolutionary thought.

But what is revolutionary is that they authors imply that the answer to our central question for US health care - "Do we get what we pay for?" - might not be the "no" we've always assumed, but a "yes." We just aren't spending enough, at least not on the proximal things that really matter. I don't think that it is that simple - it's hard to know what portion of social service spending actually improves health. But the discourse does need to move in this direction.

Furthermore, another neat aspect of this piece is that Bradley and Taylor's contention doesn't just apply to the macro-level health policy sphere. Imagine a primary care system that takes into account the socioeconomic realities of patients and creates interventions that use these insights to better provide care. A developing country example: subsidizing the transportation fees for HIV/AIDS patients who would otherwise find this to be a barrier and be unable to seek much needed health care. This sort of intervention may be equally important to any medications or lab tests in advancing the health of these patients. I'll talk more about this sort of "economic hotspotting" in a later post.

Battling the Bulge

Some innovative social policy this week in Mexico, where the federal government been expressing some palpable alarm over rising obesity among children and adults. I'm sure that Mexico now is the fattest nation in the world and, if they aren't, they are right behind the US in this dubious regard. From a country that was worried about infectious disease deaths just a generation ago to one that is increasingly burdened by diabetes and heart disease comes a new social policy that aggressively seeks to reduce obesity in children by banning junk food, increase hours of physical education, and provide nutritional education in a school based setting. Only time will tell whether they can get people to substitute agua for refrescas, but I like where they are headed with this multi-pronged approach. I know there is some evidence that each of these interventions could provide positive benefits alone (see, for example, here), so perhaps there will be a bigger kick from all three together.

On our side of the border comes some new evidence that your neighborhood matters as far as obesity goes. A study in this week's New England Journal of Medicine finds that poor households randomized to receiving housing vouchers enabling them to move to nicer neighborhoods were significantly less likely to be obese and have elevated hemoglobin A1c levels (a marker of blood sugar content used to diagnose, and track response to treatment for, diabetes). This experiment validates a long-standing hunch that neighborhoods matter for obesity. The question now is what exactly matters, i.e., what is the mechanism behind this causal pathway? We obviously need to know this in order to design targeted policies? Is it that better neighborhoods have better designed streets that encourage walking? The presence of parks? Are there positive peer effects from health nuts? Better grocery stores and more healthy food options relative to junk food options? Better access to primary care docs? I'm awaiting the follow up study which tries to tease these different possibilities apart.

Absolutely Lovely Paper About Esther Duflo

Esther Duflo, hands down, is one of my favorite economists. Her work spans a rich swath of development economics, touching subjects as diverse (and, ultimately, as related!) as microfinance, education, health care, corruption, women's agency, and, central to a good deal of her work, randomized field experiments. She is also the founder of the Jameel Poverty Action lab and co-wrote the incredible Poor Economics.

Recently, she won the American Economic Association's John Bates Clark Medal, an bi-yearly award given to the topic economist under the age of forty. Chris Udry, one of my favorite professors at Yale, ruminates on Duflo's work in a beautiful essay in the Journal of Economic Perspectives. Reading it, one is amazed about the impact one person can have on an entire field - disruptive technological change at its finest! My favorite part about the piece is how Duflo has remained an incredible academician while also serving as a public intellectual and activist. Excellent stuff.

More on Corruption in the Public Sector

This time the relationship between elections and corruption. Suprise surprise, but elected officials respond to incentives, too:

We show that political institutions affect corruption levels. We use corruption audit reports in Brazil to construct new measures of political corruption in local governments and test whether electoral accountability affects the corruption practices of incumbent politicians. We find significantly less corruption in municipalities where mayors can get reelected. Mayors with re-election incentives misappropriate 27 percent fewer resources than mayors without re-election incentives. These effects are more pronounced among municipalities with less access to information and where the likelihood of judicial punishment is lower. Overall our findings suggest that electoral rules that enhance political accountability play a crucial role in constraining politician’s corrupt behavior.

Great paper, and in the June 2011 issue of the American Economic Review.

Poor Economics

I am working through this great book by MIT economists Abhijit Banerjee and Esther Duflo called Poor Economics. This beautifully written tome goes through various problems in economic development and discusses how evidence from the fast growing array of randomized field experiments in development economics can be used towards designing incisive policy interventions. What I love about this book is that it is theoretical and practical all at once. While there is still a healthy debate over the utility of experiments in development economics (see this recent post by Chris Blattman, and this one), what can't be argued is the importance of this methodology as at least a complementary tool in our quest to understand why some places are poor and others are not.

One of my favorite aspects of this new book is the accompanying website (linked above). In addition to access to various tables and datasets for 18 different countries, the website has a link to lectures on Banerjee and Duflo. The lectures on health, in particular, are quite interesting: they cover prevention, deworming, the importance of information, and the role of health in development. Some of these are practical resources that would be highly useful for health care practitioners who are interested in global health.

Lost in the Mail

I just read an interesting paper by Marco Castillo and coauthors on crime in Peru. The study involves a field experiment where the researchers sent out a bunch of envelopes to people involved in the experiment. They signaled the presence of valuable items in the envelopes by making them thicker and/or implying that the letters were sent between relatives (who might be more likely to send valuable things).

This is a clever paper with three really interesting findings:
1) 18% of the envelopes never made it to their destination.
2) Thicker envelopes and those addressed to putative relatives were far less likely to make it.
3) Mail sent to poor neighborhoods did not make it to its destination 18% of the time and mail sent to really rich neighborhoods failed to arrive about 10% of the time. Where most of the mail was lost is in middle income neighborhood. Apparently, this is where the trade-off between the expected value of the envelope contents and the risk of facing retribution due to complaints from influential people is maximized.

Here's the kicker: Peru's mail system is privatized. While privatization is often tossed around as a solution to inefficiencies in developing countries, this paper makes the great point that such changes may have little impact if employees in the system are not held accountable. Ultimately, bad incentives are bad incentives are bad incentives.

Write Our Future...

...is the name of a fantastic NGO that my good friends Brendan and Rebecca Maughan-Brown have started in South Africa (you may recognize Brendan as a frequent co-author of mine in previous posts). The broad goal of WoF is to intervene on disadvantaged children in South Africa to improve health, nutrition and education.

Currently, the Maughan-Browns are working towards providing school-based meals for 100 children for an entire year in the Eastern Cape, where budget issues have led to the cessation of a government-funded program doing the same. It's a great cause, as school meals have been shown to increase attendance and perhaps even test scores, both of which can have important long-run benefits.

I encourage you to donate if you are interested. The Maughan-Browns are smart people looking for evidence-based, high impact interventions. They are running WoF with low overheads, guaranteeing that your money is well spent.

Interesting Global Health Policy Articles

The January 2010 issue of PLoS Medicine contains four interesting articles on the "global health system" The articles define what this system is, discusses the role of nations within this larger system and talks about how to strengthen it's effectiveness. These pieces are written by leaders in the field and provide some concrete discussion on a concept that has gained currency over the last few years, that global health is a policy domain of importance and that nations can be thought interlinked as part of a larger "health ecology" when developing policies to address morbidity and mortality the world over.

For more on global health and global health governance, you may want to check out this interview of one of my thesis committee members, Yale University Professor Jennifer Prah Ruger. Her work (linked here) focuses on this broader global health system, linking insights from ethics, politics, policy and economics to understand how and when investments in international health are and should be made.

Finally, for a topical piece on health care worker shortages worldwide, and the role of the United States in alleviating these, see this great essay by Yale medical student (and my former roommate!) Dayo Fadelu.

World Oil Prices and Child Health

Yale Political Science graduate student Brian Fried and I have a new working paper looking at how fluctuations in world fuel prices impact child respiratory health. Here is the abstract:

Acute respiratory infections secondary to indoor air pollution from the use biomass fuels such as wood, dung and crop residues, are an important but under-explored cause of morbidity and mortality among children in the developing world. Designing policies to address this issue requires an understanding of the determinants of household fuel choice. This study explores one particular determinant, fluctuations in world fuel prices, which impact the local prices of clean-burning fuels such as liquid propane gasoline (LPG). Using a rich, nationally representative survey dataset from Guatemala, we explored the association between shocks to world fuel prices, measures of household biomass fuel use, and the respiratory health of children under the age of six. Our core finding was that a $1 (3.6%) increase in the (one week lagged) world oil price was associated with nearly a 3 percentage point increase in the likelihood of a child under the age of six experiencing respiratory symptoms. This association is likely driven by changes in household fuel use: increases in oil prices were associated with increases in the time spent cooking by the child’s mother and by the likelihood that the household collected firewood, both of which indicate a switch to biomass fuels. In addition, the fuel price effect on child respiratory health was strongest among very young children, who are more dependent on their mothers and therefore are more exposed to cooking smoke, and was nonexistent in areas that did not have markets for LPG, where substitution across clean and dirty fuels is not possible. Our results have important implications for policies aimed at reducing the burden of disease from respiratory illnesses secondary to exposure to pollutants from biomass fuels.

Economic Shocks, Risky Sexual Behavior and the HIV/AIDS Epidemic

The relationship between poverty and HIV/AIDS is a tricky one to pin down empirically. Studies have found widely different associations between SES and the likelihood of having been infected, though the positive association between education and HIV risk appears to be stable across time and space (see this excellent paper by Jane Fortson).

Aside from permanent economic status, transitory shocks may have some impact on the HIV/AIDS epidemic, as well. The idea is that bad times may induce people to engage in riskier sex because of market returns to such behaviors. The possibility of transient shocks in driving sexual behavior and, consequently, the HIV/AIDS epidemic is an intriguing one, especially given the potential prominence of "transactional sex" - sex in exchange for gifts, favors, etc (i.e., not necessarily prostitution!) - in African countries.

Two recent papers having examined this issue in the context of commercial sex workers. A study by Pascaline Dupas and Jonathan Robinson looks at the effects of political instability in Kenya circa 2007, which led to civil conflict and adverse economic times, on the behavior of commercial sex workers (CSWs). They find that CSWs were more likely to engage in unprotected sex after the adverse shock. A paper by Robinson and Ethan Yeh tells a similar story: CSWs in Kenya were more likely to have a variety of different types of riskier sex in response to income shocks. Both of these studies are well done from the stand point of data collection (how many people have panel data on CSWs??) and statistics (causality is plausibly inferred from both pieces).

In some African countries, however, CSW is not a common practice while transactional sex, more broadly, is. In such areas, it would be interesting to look at how the sexual behaviors of the general population respond to income shocks. My colleague Brendan Maughan-Brown, from the University of Cape Town, and I are working on this in the context of Khayelitsha, a township of Cape Town, SA, where antenatal clinic data indicates an HIV/AIDS of over 30%. Using longitudinal data from an effectively random sample of the township, we found (from individual fixed effects models) that people responded to income shocks by reducing condom usage. Interestingly, we found the same result when looking at individuals who were on anti-retroviral therapy for HIV/AIDS (draft forthcoming - will keep you posted).

We are currently trying to understand whether our results reflect a price mechanism (individuals cannot afford to pay the cost of obtaining and using condoms during bad times) or a consumption smoothing mechanism (individuals engage in riskier sex to get by during bad times). Either way, we have compelling evidence that economic shocks may play a role in driving the HIV/AIDS epidemic.

Politicians and Poverty Reduction

A long line of work in political science centers around the topic of clientelism, also known as vote buying. The idea is that politicians (the patrons) provide goods, services or benefits to the public or to those not in positions of power in exchange for votes. (Such favors, for example, could involve the allocation of a large development project to a swing-locality or district). There are lots of reasons to be displeased with "vote-buying" but a big one concerns the marginal returns to public expenditure: funds that are allocated for political reasons may not be allocated productively from the standpoint of some other societal goal. For example, if we are interested in poverty reduction, public funds should be allocated to those who are actually poor (yes, I am oversimplifying here!). Obviously, there is no guarantee that funds allocated by a political formula will follow this more technocratic logic.

So are we destined to an equilibrium where the incentives of politicians and the public are not well-aligned? Not so, according to two recent studies which examine the political impacts of conditional cash transfer programs (CCTs), which are schemes that provide cash to poor families who meet certain objectives (i.e., attending monthly check-ups, sending their children to school, etc; see here for a beautifully detailed account of CCTs the world over) and have been shown to have had numerous positive benefits on health, schooling and general circumstances faced by the poor. The first, by Yale political scientist Ana de la O, looks at the impact of the Mexican CCT, Progresa. Progresa was initially rolled out to a randomly selected subset of localities before more universal rollout a year and a half later. De la O uses this variation to show that people randomly exposed to Progresa longer are around 5 percentage points more likely to vote for the incumbent.

In the second study, Marco Manacorda, Ted Miguel and Andrea Vigorito use a regression discontinuity approach to identify the political impacts of Uruguayan CCT PANES. Comparing individuals just on either side of a pre-designated eligibility score (based on a composite of household and individual socioeconomic characteristics), they find that cash transfers lead to a whopping 21-28 percentage point increase in the probability of voting for the incumbent!

What I like about these papers, besides the use of program evaluation methods to identify causal impacts on voting behavior, is that it suggests that there is a better equilibrium out there: politicians can get re-elected on the basis of policies that have demonstrated large and positive effects on human development rather than through doling out public funds in potentially unproductive ways. My hope is that this catches on in other parts of the world...

Easterly/Sachs Debate and Other Links

1. Bill Easterly and Jeffrey Sachs have a lively back-and-forth going on the Huffington Post about how best to tackle global poverty (see here and click the links for previous posts). The debate is informative and also fun from an entertainment standpoint.

2. Nice post from Steve Levitt about how free-markets and poverty reduction strategies can co-exist.

3. If you're bored or devoid of fun these days, here you go.

Now Online: My Talk on Disability Grants and Adherence to HAART in South Africa

You can find it here (you'll need RealPlayer or RealAlternative to view it). Here is a description of the study, conducted by myself, Brendan Maughan-Brown (University of Cape Town), Nicoli Nattrass (University of Cape Town) and Jennifer Ruger (Yale) from a previous post.

We are currently working on a new draft of this paper and should have that ready in a week or so. In the meantime, I'd love to hear your comments on how to improve upon this study.

HIV/AIDS and the Erosion of Medical Care

A new and important paper by Anne Case and Christina Paxson finds the following:

We document the impact of the AIDS crisis on non-AIDS related health services in fourteen sub-Saharan African countries. Using multiple waves of Demographic and Health Surveys (DHS) for each country, we examine antenatal care, birth deliveries, and rates of immunization for children born between 1988 and 2005. We find deterioration in nearly all of these dimensions of health care over this period. The most recent DHS survey for each country collected data on HIV prevalence, which allows us to examine the association between HIV burden and health care. We find that erosion of health services is highly correlated with increases in AIDS prevalence. Regions of countries that have light AIDS burdens have witnessed small or no declines in health care, using the measures noted above, while those regions currently shouldering the heaviest burdens have seen the largest erosion in treatment for pregnant women and children. Using semi-parametric techniques, we can date the beginning of the divergence in health services between high and low HIV regions to the mid-1990s.

Case and Paxson are unable to pin down a mechanism for why this is happening. They suggest it is not driven by an erosion of wealth (though the data they use is somewhat lacking in measures of health beyond asset ownership) or reduced demand for medical care by HIV+ mothers. On the other hand, they cannot rule out adverse impacts of HIV/AIDS on the supply of health care workers and/or the diversion of resources to those with HIV/AIDS, perhaps at the expense of other aspects of medical care. As such, the authors rightly point out that there is more work to be done and that this work needs to be done very soon.

I'll have more to say about this in a forthcoming post.

The Human Development Index

Justin Wolfers put up an interesting post on the Freakonomics blog today about the Human Development Index (HDI), a summary statistic that combines information on life expectancy, schooling outcomes and income per capita. He cites a post by Andrew Gelman, which makes the claim that the Human Development Index for the 50 U.S. states provides little information above and beyond what state income per capita tells you.

Some thoughts:

1) The HDI was first developed in 1990 as a good faith effort to move beyond income as a measure of development. The idea was to capture other aspects of society and wellness that we might think are important in making people content and happy. The fact that there is little information beyond what a simpler measure of income per capita tells you is discouraging on the one hand, as it might imply that we aren't measuring non-monetary aspects of development well. On the other hand, the finding might suggest that wealth creation brings about the other aspects of development we care about, even if these other aspects are important ends in and of themselves.

2) It is important to ask what the content of the HDI is, how it is calculated, and its utility in informing policy. On this note, I'm a bit surprised that neither Wolfers or Gelman cite a seminal paper by my mentor from Duke, Allen Kelley. Written in 1991, Kelley notes the close correspondence between national income per capita and HDI, but also goes into the sausage factory of how the HDI is constructed (its a bit arbitrary) and what the statistic may or may not be able to tell us. The subtitle of his piece, "handle with care," gives you a good sense of his skepticism. The fact that the same skepticism remains warranted nearly 20 years later is more than a bit disturbing.

3) Finally, the blog fivethirtyeight.com is fantastic: the authors use data and elegant statistics to delve deeper into various political and social issues that are often taken for granted. It was first recommended to me by Joachim Hero, and I am now linking it in the sidebar for your enjoyment.

Links: Obama on Global Health, Kindergarten, and the Indian Marriage Market

1. Karen Grepin provides a nice discussion on Obama's comprehensive strategy on global health. While you are there, check out her interesting piece on advocacy and neglect in the global health arena.

2. In an interesting new paper, Elizabeth Cascio finds that the introduction of kindergarten programs in the 1960s and 70s led to reduced drop out and institutionalization rates among whites but not blacks. The differential effect, she posits, might have something to do with crowding out federally funded programs helping the poorest black five year olds. I'm not so convinced about this as the mechanism, and I think there is a study waiting to happen that looks at health effects, as well.

3. A fun new paper by Abhijit Banerjee and co-authors looks at the Indian marriage market. From the abstract:

This paper studies the role played by caste, education and other social and economic attributes in arranged marriages among middle-class Indians. We use a unique data set on individuals who placed matrimonial advertisements in a major newspaper, the responses they received, how they ranked them, and the eventual matches. We estimate the preferences for caste, education, beauty, and other attributes. We then compute a set of stable matches, which we compare to the actual matches that we observe in the data. We find the stable matches to be quite similar to the actual matches, suggesting a relatively frictionless marriage market. One of our key empirical findings is that there is a very strong preference for within-caste marriage. However, because both sides of the market share this preference and because the groups are fairly homogeneous in terms of the distribution of other attributes, in equilibrium, the cost of wanting to marry within-caste is low. This allows caste to remain a persistent feature of the Indian marriage market.

Imports and Development

It's always fun when a friend or colleague of yours is mentioned in The Economist. Last week was no exception, when the venerable periodical covered a recent piece on trade co-authored by Amit Khandelwal, a former Yale economics graduate student now at the Columbia Graduate School of Business as an assistant professor.

The research in question looks at the effects of imports on aspects of economic development. As the Economist piece points out, in policy discussions on trade, there is this belief that exporting is good for the home country's development, but importing is not. Khandelwal et al's piece shows that, in the case of India, imports have had some positive benefits. Quoting from the news article:

As part of those reforms, India slashed tariffs on imports from an average of 90% in 1991 to 30% in 1997. Not surprisingly, imports doubled in value over this period. But the effects on Indian manufacturing were not what the prophets of doom had predicted: output grew by over 50% in that time. And by looking carefully at what was imported and what it was used to make, the researchers found that cheaper and more accessible imports gave a big boost to India’s domestic industrial growth in the 1990s.

This was because the tariff cuts meant more than Indian consumers being able to satisfy their cravings for imported chocolate (though they did that, too). It gave Indian manufacturers access to a variety of intermediate and capital goods which had earlier been too expensive. The rise in imports of intermediate goods was much higher, at 227%, than the 90% growth in consumer-goods imports in the 13 years to 2000.

Good stuff.