Thread by @ChrisMusson

We report today on a senior Scot Gov public health official using an arguably misleading & inaccurate deaths stat in Friday's Scot Gov televised Covid briefing, in order for the gov to back up its controversial argument it nearly eliminated Covid in summer thescottishsun.co.uk/news/scottish-…

In short, national clinical director Prof Jason Leitch suggested there were no Covid-related deaths between July 17 & Aug 18. There were in fact 24

Even if you examine his claim with a caveat he gave in response to one of two Qs on the issue, there was 1.

More detail follows

Prof Jason Leitch was responding to Edinburgh Uni epidemiologist Prof Mark Woolhouse's claims on Thurs that Scotland did not get close to elimination. Woolhouse's comments were widely reported, eg: thescottishsun.co.uk/news/6737272/c…

First, Leitch was asked by me re Woolhouse's comments.

He said: "Nobody died of Covid for a month between July 17 and August 18. Nobody died of Covid between July 17 and August 18, 28 days after a positive Covid test."

Q:
A:

After a later Q by @Georgina__Hayes, Leitch said: "We didn't eliminate the virus but we maximally suppressed it. We had a month with nobody dying of Covid, 3 months after a lockdown." 

Q -
A -

Note: Prof Leitch said the deaths were "28 days after a positive Covid test" to me, but not to @Georgina__Hayes

Two problems with these comments from Prof Leitch.

1. There were 24 Covid-related deaths on days during this period, according to National Records of Scotland.

2. Even if we measure deaths after a +ve test, there was 1, not none.

So the clear suggestion that nobody died for a month is wrong. 

And even if you think it's ok because Prof Leitch mentioned "after a positive Covid test" to me, it's still wrong. Because there was one.

(Thought experiment: Pretend claim of 0 deaths after a +ve test was correct & you think it's ok to use this measure as it's *technically* right. Ask yourself: What would an average viewer take from his statement? If the answer is 'There were no Covid deaths', they were misled)

Back to the stats so you know I'm not making it up. National Records of Scotland shows 24 Covid-related deaths between 17/7 and 18/8 here - see 'Figure 2 Data' here nrscotland.gov.uk/files//statist…

Public Health Scotland data shows one death after a positive test occurred on July 25 - so, in the period Prof Leitch claimed no deaths after a positive test. Data and defintions below. Available here.  public.tableau.com/profile/phs.co…

It seems Prof Leitch's carefully plucked zero deaths figure is from deaths *registered* (not occurred) daily of those who died within 28 days of a positive test. These are the figures read out at Scot Gov TV briefings. No deaths were *registered* under this measure from 17/7-18/8

If Prof Leitch was being accurate & showing full picture, he could have said something like:"From 17/7 to 18/8, no deaths of Covid patients were registered within 28 days of a positive test, however 24 Covid-related deaths happened including one death of a Covid-positive patient"

But then that wouldn't really have bolstered the Scot Gov line that Covid was nearly eliminated in Scotland last summer, or helped to debunk epidemiologist Prof Mark Woolhouse's comments on Thurs that it was not actually close to being eliminated

Why have I done a big, moany thread on this? Because we are told policy is being "driven by data".

Politicians spin figures - that's what they do.

But we need to be able to trust what we're told by public health officials at Covid briefings.