A Literature Review and Meta Analysis of the Effects of Lockdowns on COVID 19 Mortality

WEight (1/SE)
left. 38 Figure 5 also shows that four <strong>of</strong> eight studies with at least 3 <strong>of</strong> 4 quality dimensions find
that SIPOs increase COVID-19 mortality by 0.8% to 13.1%.
Figure 6: Funnel plot for estimates from SIPO studies
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120
100
80
60
40
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-50.0% -40.0% -30.0% -20.0% -10.0% 0.0% 10.0% 20.0%
Estimate (Estimated Averted Deaths / Total Deaths)
2 <strong>of</strong> 4 quality dimensions or fewer At least 3 <strong>of</strong> 4 quality dimensions
Note: The figure displays all estimates <strong>and</strong> <strong>the</strong> precision <strong>of</strong> <strong>the</strong> estimate defined as one over <strong>the</strong> st<strong>and</strong>ard error. Studies where
st<strong>and</strong>ard errors are not available are not included. Studies which live up to at least 3 <strong>of</strong> 4 quality dimensions are marked with
white, while studies which lives up to 2 <strong>of</strong> 4 quality dimensions or less are marked with black. The vertical line illustrates <strong>the</strong>
precision-weighted average.
Overall conclusion on SIPO studies
We find no clear evidence that SIPOs had a noticeable impact on COVID-19 mortality. Some
studies find a large negative relationship between lockdowns <strong>and</strong> COVID-19 mortality, but this
seems to be caused by short data series which does not cover a full COVID-19 ‘wave’. Several
studies find a small positive relationship between lockdowns <strong>and</strong> COVID-19 mortality. Although
this appears to be counterintuitive, it could be <strong>the</strong> result <strong>of</strong> an (asymptomatic) infected person
being isolated at home under a SIPO can infect family members with a higher viral load causing
more severe illness. 39 The overall effect measured by <strong>the</strong> precision-weighted average is -2.9%.
The result is in line with Nuzzo et al. (2019), who state that “In <strong>the</strong> context <strong>of</strong> a high-impact
38
This could indicate some publication bias, but <strong>the</strong> evidence is weak <strong>and</strong> with only 13 estimates, this cannot be
formally tested
39
E.g. see Guallar et al. (2020), who concludes, “Our data support that a greater viral inoculum at <strong>the</strong> time <strong>of</strong> SARS-
CoV-2 exposure might determine a higher risk <strong>of</strong> severe COVID-19.”
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