There are some claims that the ongoing randomised trial of Daily Contact Testing (DCT) vs blanket quarantine/isolation in schools for cases of #COVID19 is "unethical"
Here is a short thread on why that is completely wrong
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Here is a short thread on why that is completely wrong
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Randomised trials are indicated (ethical) when we have "equipoise", meaning we can't be sure which of some options is better
We want to get the best of all outcomes, e.g. a pill which is really good at treating mild coughs but frequently causes cancer is not good overall
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We want to get the best of all outcomes, e.g. a pill which is really good at treating mild coughs but frequently causes cancer is not good overall
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For COVID-19 cases in schools, we know that we want to avoid transmission, but we also know that children missing school is harmful
There is equipoise as to whether the best of *all outcomes* is blanket quarantining of bubbles, or doing DCT
But wait, there's more
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There is equipoise as to whether the best of *all outcomes* is blanket quarantining of bubbles, or doing DCT
But wait, there's more
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Imagine you are a 15yo sent home with your entire year group because of a case in another class
Your parents don't have to isolate, so off they go to work
Do you:
A) Stay home all day like you're supposed to
B) Go and see all your mates who are also not in school
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Your parents don't have to isolate, so off they go to work
Do you:
A) Stay home all day like you're supposed to
B) Go and see all your mates who are also not in school
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Also in this scenario, if you are a 15yo asymptomatic positive case you might never find out
You could infect your parents, who go to work and don't realise until they are symptomatic (too late)
The chain of infection continues
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You could infect your parents, who go to work and don't realise until they are symptomatic (too late)
The chain of infection continues
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Now imagine instead, you are the same 15yo doing daily tests
You test positive within a few days, and immediately you and your family all self isolate
Chain of transmission broken before your family infect others
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You test positive within a few days, and immediately you and your family all self isolate
Chain of transmission broken before your family infect others
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So, there are plausible reasons why DCT might not only minimise time off school, but also be BETTER at interrupting transmission
This might not work at all, and blanket isolation/quarantine may be much more effective
But we have absolutely no idea
That's why we do trials
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This might not work at all, and blanket isolation/quarantine may be much more effective
But we have absolutely no idea
That's why we do trials
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I am genuinely proud of the UK for investing huge resources into answering some of these questions, rather than just implementing interventions with no idea how effective that might be (although we are doing that too...)
The world will be eager to see the results
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The world will be eager to see the results
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