India's situation is messy because of the different states policies.
To properly do this one would need to control for incidence and lockdown policy state-by-state. Also some states have no approval for Ivermectin yet it gets used.
My best bet is that we'll get the cleaner data on whether it works from Europe, in particular from Slovakia and Czechia.
Even if EMA advises against Ivermectin, Slovakia approved it for both prophylaxis and treatment in late January 2021.
I could not find how widespread the slovak usage of Ivermectin is, but there are few points:
I've not found data on the delta variant incidence in Slovakia, maybe it didn't reach there yet. It's 98% of cases in UK, 30% in CZ.
If Slovakia sees a ramp up in delta cases the Ivermectin proponents will likely say it wasn't used enough/correctly, and the detractors will keep saying it was useless from the start.
On the other hand, if Slovakia does not see a ramp up in delta cases whilst keeping a low vaccination rate and no effective lockdown in place it'd suggest something else must be at work.
Saying it's Ivermectin will come off as reasoning from exclusion but it'd be my best-bet hypothesis.
The article is mostly a narrative backed by anecdotes. The question here is whether it's possible to answer the question in a statistically more rigerous manner.
This specific article struck me for the area of Uttarakhand ...it is needed to understand the prevalence of docs giving IVM as prophylaxis to an entire house where a Covid patient resides.
https://www.hindustantimes.com/lifestyle/brunch/a-crown-of-care-during-covid-101615047368077.html
I frequently read the claim that India reduced their COVID-19 cases a lot via Ivermectin but it's very unclear to me whether the relevant data to make that claim is cheripicked.
India has 34 region and each of those region has their own policy on Ivermectin. While we don't have exact data about Ivermectin usage, Google Trend data provides a proxy for usage of Ivermectin and does provide data that's fine-grained enough to separate individual region. John Hopkins provides data for COVID-19 cases by Indian region as well. 34 regions sounds to me like it's plausible to find statistically significant results if Ivermectin had an effect that's as great as proponent of Ivermectin claim
Given p-hacking concerns, it makes sense to first decide on how to analyse the data and then run the statistics. Does anyone have suggestion for how the data should be analysed?