I downloaded the latest IHME update of its COVID-19 projections yesterday to do another evaluation. Their projections still look very problematic. Other disease modellers and epidemiologists are coming to the same conclusion. An article just published in Statnews was much less polite than I was in my previous post. This article quoted epidemiologist Ruth Etzioni as saying “That it is being used for policy decisions and its results interpreted wrongly is a travesty unfolding before our eyes.”
The Statnews article claims that the IHME model may have influenced Trump’s thinking on when to re-open the country, and that IHME’s early very high projections for the USA are likely to be used by Trump to claim the government response has prevented a great catastrophe.
An article in the Washington Post is also highly critical of IHME and reviews the various other models in use which enable the impacts of social isolation to be better taken into account along with the epidemiological characteristics of the epidemics. A critique from researchers at Imperial College and LSHTM was also published this week in Annals of Internal Medicine and stated that the IHME projections are based “on a statistical model with no epidemiologic basis.”
These articles also note the volatility of the projections to updates of a few extra days data and like me see this as evidence of a very poor predictive model. The main impact of a model like this where the results vary wildly from one update to the next (as opposed to from one scenario to another) are very likely to reduce public/political confidence in all modelling. And this could lead to more deaths.
Having read these various other critiques, I don’t think I will bother to do a second evaluation of IHME’s latest updated projections now.