There is strong evidence that when large numbers of people use LLINs to protect themselves while sleeping, the burden of malaria can be reduced, resulting in a reduction in child mortality among other benefits.
Insecticide‐treated nets reduce child mortality from all causes by 17% compared to no nets (rate ratio 0.83, 95% CI 0.77 to 0.89; 5 trials, 200,833 participants, high‐certainty evidence). This corresponds to a saving of 5.6 lives (95% CI 3.6 to 7.6) each year for every 1000 children protected with ITNs. Insecticide‐treated nets also reduce the incidence of uncomplicated episodes of Plasmodium falciparum malaria by almost a half (rate ratio 0.55, 95% CI 0.48 to 0.64; 5 trials, 35,551 participants, high‐certainty evidence) and probably reduce the incidence of uncomplicated episodes of Plasmodium vivax malaria (risk ratio (RR) 0.61, 95% CI 0.48 to 0.77; 2 trials, 10,967 participants, moderate‐certainty evidence).
If the nation-level data isn’t supportive of this, then perhaps this is worthy of further investigation to understand why it may be different from the trials.
You seem to acknowledge this by saying ‘Maybe the RCT evidence is so convincing that the noise of country-level data doesn’t matter’ - but if your claim is that there is ‘no evidence of impact’ specifically at the country-level, then I’d encourage you to be clear about this with your heading. The statement that ‘when you try to measure outputs there is no evidence of impact’ doesn’t seem true.
Thanks for the comments Matt. I’ve adjusted and improved the post based on your input.
I was aware of this info and assumed everybody else would be too, so I just took it as read. However, I agree these points are not clear enough in the original post above.
I’ve now changed the heading to add the clarity that it only applies to non-RCT/”real world” distributions. I’ve also inserted a sentence in the final paragraph to make it clear the RCTs do show such evidence and this is the basis for GiveWell’s recommendation.
Have you read this GiveWell page on bed nets? They state:
Or this Cochrane review?
If the nation-level data isn’t supportive of this, then perhaps this is worthy of further investigation to understand why it may be different from the trials.
You seem to acknowledge this by saying ‘Maybe the RCT evidence is so convincing that the noise of country-level data doesn’t matter’ - but if your claim is that there is ‘no evidence of impact’ specifically at the country-level, then I’d encourage you to be clear about this with your heading. The statement that ‘when you try to measure outputs there is no evidence of impact’ doesn’t seem true.
Thanks for the comments Matt. I’ve adjusted and improved the post based on your input.
I was aware of this info and assumed everybody else would be too, so I just took it as read. However, I agree these points are not clear enough in the original post above.
I’ve now changed the heading to add the clarity that it only applies to non-RCT/”real world” distributions. I’ve also inserted a sentence in the final paragraph to make it clear the RCTs do show such evidence and this is the basis for GiveWell’s recommendation.