I'd agree with you Florian. The Cost / Benefit analysis of rural roads (and even electrification) is probably relatively easy to perform simply by looking at rural economies, access to markets for agricultural goods and so on, and its easy to demonstrate the "bankability" of infrastructure projects in general.
Its much harder to show the effects of behavioural changes in society and even harder when there is a subjective eye on the monitoring of results (as needs to be done for sanitation and hygiene). The bias in reporting impacts seems at the moment somehow inevitable.

I saw this morning that IRC have picked up on this story on their relaunched E-Source weekly, adding some recent figures for their impact on the GBD of poor sanitation and hygiene. (Interesting too that they also mention environmental enteropathy in this context.) However the criticism remains the same. As the original author of the paper said when contacted to comment on the new WHO figures:

"The main problem with this review and analysis of the burden of disease attributable to poor water and sanitation are the same as with previous attempts: the included studies have substantial methodological problems. The effect estimates are largely a summary of the almost inevitable bias and confounding present in most of the included studies. The review may have been politically necessary to counter the even more questionable estimates from the recent Global Burden of Disease Study. However, one should be under no illusion as to the validity of the findings. While water and sanitation are likely to fundamentally improve people's lives, wellbeing and health in poor settings, epidemiological research may not be the right tool to prove this."

See here: www.ircwash.org/news/elusive-health-impa...-f9dd48ec3d-21332705

JKMakowka wrote: I am for example sure that a in-depth study would reveal a horrible price/impact ration for road construction (as compared to rail-ways for example), yet it is one of the most well funded activities.

Similarly rural electrification often has very limited impact beyond some lightning and entertainment (for the richer), which could be provided much cheaper with decentralized solutions (e.g. solar powered).

I'm sure rural roads and elecrification have huge impacts on rural economy, generating income and alleviating poverty. As does water supply.

Very interesting discussion, but I need to read that article properly first...

Well, one could say that the entire focus on the health aspects is what brought the difficulties in measuring the impacts, as compared to the relative ease in the case of drugs (double bind tests etc.).

And certainly most people in developing countries seem more interested in the non-health benefits of water & sanitation infrastructure.

My point is basically, that other basic infrastructure projects seem to face much less scrutiny (well intended or not), i.e. huge amounts of public investments go into transportation and power infrastructure and you rarely hear of double-blinded impact studies and such for those.

I am for example sure that a in-depth study would reveal a horrible price/impact ration for road construction (as compared to rail-ways for example), yet it is one of the most well funded activities.

Similarly rural electrification often has very limited impact beyond some lightning and entertainment (for the richer), which could be provided much cheaper with decentralized solutions (e.g. solar powered).

Yet similarly to water & sanitation infrastructure the long term benefits of both are probably also quite significant but difficult to measure.

I think there a few issues brought up in the editorial which have been and remain very important regarding the WASH sector.

Firstly, and from my experience I would very much agree with this, is that within the framework of development cooperation sanitation in particular is still seen more of a convenience issue than a direct health intervention. This has of course led to the use of demand driven approaches and meeting the non-health related needs of the users / households and other market oriented approaches, all of which can only be welcomed, but does tend to "steal" the issue from the health sector somewhat - or in other words, it often lets health ministries of the hook with regard to their clear responsibility in supporting the improvement of general health conditions through supporting the improvement of sanitation and hygiene. Often the ministry of health isn't even directly involved in interventions at all. We can hardly expect then rigorous health monitoring when marketers are involved and not health professionals.

Secondly I find it interesting to see how biased monitoring and reporting of impacts easily attracts funders, desperate to report some kind of success. This not only applies to the handwashing and household treatment examples given, but I think also to the CLTS "bubble" of incredible numbers of ODF villages, and to a large extent to many UDDT projects over the last 10 years that reported through rose-tinted glasses. Fronts then build not along evidence based results but on ideological lines and energy is lost for actual progress. Given how quickly good results can obtain funding one can understand the tendency to optimistic reporting (as well as the fact that those involved really do believe they are making a dramatic difference), but it doesn't excuse it.
The whole childhood enteropathy discussion risks being sucked into this kind of debate I fear.

And yet the question remains - how to support a shift towards greater investment in the sector? Its not easy, less so knowing that "the literature on the impact of water supply, sanitation and hygiene is unreliable in its entirety".

I would rather say that the conclusion of the article is that despite (very flawed) evidence that water & sanitation improvements have relatively little impact, it is still one of the most important health interventions. However due to the complexity of the issue (short term & conceptually limited) scientific studies fail to measure that.

While the article is more of an opinion piece, I very much agree with it... but how to advocate for a shift of public investment without so called "hard evidence" is one of the main issues the WASH sector is facing.

Dear all,
I recently read the attached paper and found it fascinating. In a way it challenges the conventional wisdom that there is a de facto improvement in the burden of disease resulting directly from improved sanitation, hygiene and / or water supply interventions and calls for better and, more importantly, long term epidemiological monitoring of the situation.
As the paper states "A good sanitation marketing campaign may require 5 -10 years to achieve a marked increase in latrine coverage with the potential impact on health". National governments may even have difficulty committing to this kind of time scale, never mind donors.

++++++
Paper details:
Editorial
The elusive effect of water and sanitation on the global burden of disease
Wolf-Peter Schmidt
Department of Disease Control, London School of Hygiene and Tropical Medicine, London, UK

Article link: onlinelibrary.wiley.com/doi/10.1111/tmi.12286/full