The GiveWell Blog

The Carter Center

(updated on: ) | by Elie

I’ve spent a good part of the past month reviewing The Carter Center in depth. We found out about The Carter Center though referrals from an advisor and donor, and through the Gates Award for Global Health.

We chose to investigate The Carter Center further for four reasons:

  1. Strong track record of success. The Carter Center has been credited with leading the global effort to eradicate guinea worm. In 1986, when Carter got involved, there were 3.5m annual cases of guinea worm. In 2008, there were fewer than 5,000. Guinea worm has been eliminated from 12 of the 18 countries that were once endemic. This chart shows the decline in cases from 1989-2007 (PDF). (More information about guinea worm and its symptoms is available on The Carter Center website.)
  2. Strong program selection. Other Carter Center programs have strong evidence of effectiveness supporting them. The interventions they implement to control or eliminate neglected tropical disease including river blindness, trachoma, lymphatic filariasis, and schistosomiasis are recommended by the experts at the Disease Control Priorities Project.
  3. Monitoring and evaluation. For its health programs, The Carter Center often monitors not only the number of drugs distributed in each region but disease prevalence directly. This monitoring isn’t evident for every single program or region, but it is far more consistent than any other complex organization we’ve seen before.
  4. Transparency. All the information we’ve used to research The Carter Center is available publicly on their website. For example, the detailed program reports I mentioned above are available here. For an example of the type of monitoring conducted for its guinea worm program, see the latest monthly report linked here.

I still have some large, unanswered questions about The Carter Center, and we aren’t yet ready to recommend them.

Financial Times on microfinance (and the need for better info about it)

(updated on: ) | by Holden

PDF here (via Innovators for Poverty Action, whose research is featured). After discussing the Karlan/Zinman study showing benefits for loans (which we summarize here), it continues:

Karlan is the first to warn against extrapolating too much from a single experiment. “This is the last thing in the world that I would use to develop policy,” he warns. “You’ve got to replicate.”

The trouble is that the replication just isn’t happening. For all the optimism about microfinance – and the [Karlan/Zinman] experiment only encourages that optimism – it is striking how much we do not know about when it works, and why.

This matters because non-commercial microfinance projects often depend on donor subsidies. And while microfinance has a good reputation among development professionals, that doesn’t mean guaranteed access to those subsidies. Not everyone is convinced that a donor grant is best used to subsidise a loan rather than, say, pay directly for a primary school. More credible evaluation would help preserve the programmes that deserve to be preserved.

Already, solidly held beliefs about microfinance have been shaken. The “group liability” system, in which a group of borrowers guarantee one another’s loans, is still supposed by many to be the secret behind Grameen Bank’s low default rates. But a randomised trial in the Philippines conducted by Karlan and aWorld Bank economist, Xavier Gine, found that group liability was discouraging new customers without improving repayment rates. Grameen itself quietly dropped group liability some time ago.

Another sacred cow of microfinance is that women make best use of the money – the Grameen Bank says that 97 per cent of its borrowers are women. But another randomised trial, conducted in Sri Lanka by a team of researchers including David McKenzie of the World Bank, found that male borrowers seemed to make a far higher return on their capital. As with the ZaFinCo study, it’s just one experiment in one country. Yet it raises a worrying question: for how long will donors fund microfinance projects with so little compelling evidence about exactly what kinds of project really work?

It also discusses why the Karlan/Zinman’s results might not be generalizable:

[The experiment’s] clients were ideal customers for a commercial lender: they were city-dwellers and therefore cheap to reach; they were poor enough to want loans but rich enough that the loans were profitably chunky. A peasant farmer in Ethiopia or Sudan ticks none of those boxes: living in the middle of nowhere, he is expensive to reach and he is so poor that he can only afford tiny loans. Trapped in a barren economic ecosystem, he has no job that a ZaFinCo-style loan can help preserve, and no business prospects either. A mere loan will not catapult him into the ranks of the entrepreneurial class. Then there are the destitute, the disabled, the elderly and the orphans. Such people cannot repay loans at a rate that would cover costs. Heavy subsidies or outright grants would be needed. “All people are entrepreneurs,” says Muhammad Yunus. If only he were right.

And indeed, a more recent randomized trial of microfinance has preliminarily found far less encouraging results (discussed in this interview on Philanthropy Action, co-maintained by GiveWell Board member Tim Ogden).

Microfinance/education program didn’t work as expected

(updated on: ) | by Holden

A reader was good enough to send in a Lancet article (free registration required for full text) about a well-designed study of a combination microfinance/education program in South Africa.

Study design, strengths and weaknesses

A program consisting of both loans and group meetings was rolled out to 8 villages in rural South Africa, but the villages were randomly split into 4 that received it right away and 4 that received it 3 years later. Meetings included a curriculum that “covered topics including gender roles, cultural beliefs, relation ships, communication, intimate-partner violence, and HIV, and aimed to
strengthen communication skills, critical thinking, and leadership” (pg 1975).

Researchers hypothesized that (a) women in the loan groups would have fewer experiences of intimate-partner violence (presumably due to being financially/culturally more empowered); (b) this in turn would be connected with less unprotected sex in their households; (c) this in turn would slow the spread of HIV in their villages. A very ambitious theory of how to slow the spread of HIV – but to the researchers’ credit, they specified their hypotheses formally before conducting the study, as well as registering it on ClinicalTrials.gov. Combined with the use of randomization, this study had just about all the ingredients for avoiding the plague of publication bias.

A problem with the study, which the researchers partially acknowledge (pg 1981), is that it was only conducted in 8 villages total (4 receiving the program and 4 not receiving it). Therefore, it’s hard to say with confidence that any observed differences were due to the program as opposed to other differences between one randomly chosen set of 4 villages and another. Villages were similar on most observable characteristics, but very different on a few (see pg 1980).

Results

The study concludes that the program resulted in less intimate-partner violence, but not in less safe sex or in slowing the spread of HIV.

A few possible interpretations of this result:

  • The researchers’ interpretation is that the program was responsible for reductions in violence, but that these simply didn’t translate into slowing the spread of HIV. Definitely a possibility. (If this is right, by the way, I’d call this a great program solely on the basis of its successfully reducing intimate-partner violence. That would be a great accomplishment in its own right, even if it didn’t have the hoped-for effect on the spread of HIV.)
  • It’s also possible that the program had no effect, and that the observed change was a change in reported episodes of violence. Perhaps women who participated in the program came to feel more shame about reporting these episodes. (It’s also possible that the measurement error is in the other direction – that women in the program felt more pressure to report episodes, and that the fall in violence was greater than what was measured. This is the researchers’ theory, given on pg 1982.)
  • And it’s possible that random fluctuations simply swamped any effects of the program itself. As mentioned above, it examined only 8 villages; and there was definitely a lot else happening in these villages over the time period in question. For example, the unspecified measure of “greater food security” had a huge rise across all villages studied, whether or not they received the program (see pg 1980). I can’t help but wonder: if this had been a more typical (less rigorous) study without a comparison group, would this increase in food security have been touted as a success of the program?

The one thing I feel fairly sure of after reading this study is that the researchers’ elaborate, multi-step theory of how loans and education can slow the spread of HIV didn’t come out looking great when all the facts were in. For every community program that publishes a study like this (and this is one of the very few I’ve seen), there are many more similar programs, with similarly involved theories of the linkages between credit, knowledge, health, empowerment, etc. that have simply never been checked in any way.

Antiretroviral treatment (ART): Things to look out for

(updated on: ) | by Holden

Antiretroviral treatment (ART) is one of the more well-publicized ways to help people in the developing world. The (RED) campaign puts it front and center, and the Gates Foundation places heavy emphasis on it as well. It seems at first glance like a fairly straightforward, if expensive, intervention: directly treat HIV-positive people with proven drugs to extend their lifespan and improve quality of life.

But the Copenhagen Consensus disease experts (also lead authors on the Disease Control Priorities report) make the case for caution (from pg 40 – emphasis mine):

  • Poor implementation (low adherence, development of resistance, interruptions in drug supplies) is likely to lead to very limited health gains, even for individuals on therapy. (This outcome is unlike that of a weak immunization program in which health gains still exist in the fraction of the population that is immunized.) Poorly implemented antiretroviral drug delivery programs could divert substantial resources from prevention or from other high-payoff activities in the health sector. Even worse, they could lead to a false sense of complacency in affected populations: evidence from some countries suggests that treatment availability has led to riskier sexual behavior and increased HIV transmission. The injunction to “do no harm” holds particular salience.
  • Unless systematic efforts are made to acquire hard knowledge about which approaches work and which do not, the likelihood exists that unsuccessful implementation efforts will be continued without the appropriate reallocation of resources to successful approaches. Learning what works will require major variations in approach and careful evaluation of effects. Failing to learn will lead to large numbers of needless deaths. Most efforts to scale up antiretroviral therapy unconscionably fail to commit the substantial resources required for evaluation of effects. Such evaluations are essential if ineffective programs are to be halted or effective ones are to receive more resources.
  • Many programs rely exclusively on the cheapest possible drugs, thereby risking problems with toxicity, adherence, and drug resistance. From the outset a broader range of drug regimens needs to be tested.

An ART program needs to use the right drugs, ensure compliance, be there for the long haul, and deal with side effects (both medical and behavioral). None of these are a given, with the (RED) campaign’s beneficiaries or anyone else, until you see the evidence that the programs are working.

And ART costs can be in the range of $600 per patient treated per year. Compare with vaccinations, which are estimated as saving lives for as little as $200 apiece, have a strong track record of success, and in many ways introduce less potential for complications.

Malaria treatment

(updated on: ) | by Elie

The Disease Control Priorities Report says:

The recommended treatments for malaria in areas with resistance to single drugs are combination treatments, preferably artemisinin combination therapy (ACT) (WHO 2001a, 2001b, 2003a, 2005).

But, knowing that your charity of choice runs this program is not sufficient to know that they’re improving lives. Bill Brieger at Malaria Matters points to this article in the WSJ which says:

Cures for malaria are largely designed for adults; the pills are often bitter and too big to swallow for children, who account for most of the more than one million people killed each year by the mosquito-borne disease, malaria experts say.

Bill Brieger adds:

Three challenges that are not mentioned in the article include –

  • For one, when drugs are made available for free or at reduced cost only for children, there will be leakage into wider use as health workers or medicine shop keepers will provide multiple packets of the child drugs to satisfy their adult clients/customers.
  • A second unmentioned challenge is the tendency to overprescribe malaria drugs, especially among adults. The answer to this is case management that includes diagnosis using a laboratory, but more likely rapid diagnostic tests, which can be used at the primary care level.
  • Finally there is the issue of compliance. Artemisinin-based combination therapy generally is taken twice a day for three days. If medicine providers do not counsel clients on the need for full compliance children may swallow only a few doses and not only fail to be cured but also contribute to drug resistance.

Malaria case management is a complicated process that begins with the drug manufacturer and ends in the home. All partners along the way must be [vigilant] if children’s lives are to be saved.

Surgeries performed vs. cases of blindness prevented

(updated on: ) | by Elie

We’ve written before about the possibility that surgeries to correct blindness are extremely cost effective. While summarizing the evidence of effectiveness for trachoma interventions, we’ve learned more and it’s clear that equating surgeries performed with cases of blindness prevented is plain wrong.

I read Trachoma: an overview, a literature review of the evidence of effectiveness for the SAFE Strategy, the WHO-recommended approach to trachoma control.

Matthew J. Burton, the author, reviews each of the four components of the strategy, including surgery. He writes (Pg 109, in the PDF version):

There are about 10 million people with trachomatous trichiasis (TT) worldwide who are at increased risk of developing irreversible blinding corneal opacification (CO). Surgical correction of TT probably reduces the risk of progressive CO and blindness. The indications for TT surgery vary between control programmes. Some advocate early surgery when one or more lashes touch the eye, whereas others practice epilation until more severe TT develops. As the progression of TT can be quite swift in some people, where access to ophthalmic services is limited, surgery for mild disease is a logical approach.

…

A major problem limiting the effectiveness of surgery is the recurrence of trichiasis following surgery, which can be as high as 40– 60%…. There can be a small improvement in vision following surgery of about a line of Snellen visual acuity.

The quote tells me that:

  1. Surgeries are performed for people who are at-risk of becoming blind, but not yet blind. The review doesn’t specify the probability that they’ll become blind.
  2. Surgeries are not performed on those already blind — trachoma-caused blindness is irreversible.
  3. There’s significant chance of recurrence, so performing a surgery is not the same as preventing the patient from ever having the condition again.
  4. There is some vision improvement for those with TT and low vision, but it’s extremely small. (According to Wikipedia, the Snellen visual acuity chart is the eye chart we’re all used to at the doctor’s office and one line is not much.

We don’t have the data to make a reasonable estimate of the cost per case of blindness prevented. We’ve tried unsuccessfully to find the percentage of those with TT who eventually become blind.

Assuming that it costs ~$20-60 to perform one surgery, and assuming 50% recurrence and that 50% of people with TT become blind, the cost per blindness averted would be $80-240. But, assuming 50% recurrence and that only 5% of people with TT become blind, the cost per blindness averted would be well over $1,000.

Addendum added by Holden: Adding a little more context on the ratio between TT infection and blindness. Estimates of total blindness due to trachoma vary a lot – this PLoS paper (table 3) puts the number around 3 million while this WHO report puts it closer to 1 million in the same year (37 million total people blind worldwide, 3.6% due to trachoma). Assuming constant prevalence of both TT and blindness would imply that TT turns to full-blown blindness 10-30% of the time, which in turn implies (using the 50% “recurrence risk” figure) that there’s 1 case of full-blown blindness averted for every 6-20 successful surgeries.

Surgeries have other benefits too, and with all the layers of uncertainty about prevalence, the 6-20 range could be off by a lot in either direction. It seems safe, though, to agree with the top-line statement that equating surgeries with “blindness prevented” would substantially overstate what you’re getting for your dollar.