The challenges of studying the effects of COVID lockdowns

What Scientists Have Learnt from COVID Lockdowns

(Nature) ...

Scientists have been studying the effects of lockdowns during the pandemic in the hope that their findings could inform the response to future crises. They have reached some conclusions: countries that acted quickly to bring in stringent measures did best at preserving both lives and their economies, for instance.

But researchers have also encountered difficulties. Analysing competing harms and benefits often comes down not to scientific calculations, but to value judgements, such as how to weigh costs that fall on some sections of society more than others. That is what makes lockdowns so hard to study — and can lead to bitter disagreement. 

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