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

1. Study (Author & title) 2. Date
Published
3. Journal 4. Comments regarding meta-analysis
Auger et al. (2020);
"Association between
statewide school closure <strong>and</strong>
COVID-19 incidence <strong>and</strong>
mortality in <strong>the</strong> U.S."
Berry et al. (2021);
"Evaluating <strong>the</strong> effects <strong>of</strong>
shelter-in-place policies
during <strong>the</strong> COVID-19
p<strong>and</strong>emic"
Bjørnskov (2021a); "Did
Lockdown Work? An
Economist's Cross-Country
Comparison"
Blanco et al. (2020); "Do
Coronavirus Containment
Measures Work? Worldwide
Evidence"
Bonardi et al. (2020); "Fast
<strong>and</strong> local: How did lockdown
policies affect <strong>the</strong> spread <strong>and</strong>
severity <strong>of</strong> <strong>the</strong> covid-19"
Bongaerts et al. (2021);
"Closed for business: The
mortality impact <strong>of</strong> business
closures during <strong>the</strong> Covid-19
p<strong>and</strong>emic"
Chaudhry et al. (2020); "A
country level analysis
measuring <strong>the</strong> impact <strong>of</strong>
government actions, country
preparedness <strong>and</strong>
socioeconomic factors on
COVID-19 mortality <strong>and</strong>
related health outcomes"
Chernozhukov et al. (2021);
"Causal impact <strong>of</strong> masks,
policies, behavior on early
covid-19 p<strong>and</strong>emic in <strong>the</strong>
U.S."
Chisadza et al. (2021);
"Government Effectiveness
<strong>and</strong> <strong>the</strong> COVID-19
P<strong>and</strong>emic"
Dave et al. (2021); "When
Do Shelter-in-Place Orders
1-Sep-20 JAMA Estimate that school closure was associated with a 58% decline in COVID-19 mortality <strong>and</strong> that <strong>the</strong>
effect was largest in states with low cumulative incidence <strong>of</strong> COVID-19 at <strong>the</strong> time <strong>of</strong> school closure.
States with <strong>the</strong> lowest incidence <strong>of</strong> COVID-19 had a −72% relative change in incidence compared
with −49% for those states with <strong>the</strong> highest cumulative incidence.
24-Feb-21 PNAS
29-Mar-
21
1-Dec-20
CESifo
Economic
Studies
World Bank
Group
The estimated effect <strong>of</strong> SIPO's, an increase in deaths by 0,654 per million after 14 days (significant, cf.
Fig. 2), is converted to a relative effect on a state basis based on data from OurWorldInData. For
states which did implement SIPO, we calculate <strong>the</strong> number <strong>of</strong> deaths without SIPO as <strong>the</strong> number <strong>of</strong>
<strong>of</strong>ficial COVID-19 deaths 14 days after SIPO was implemented minus 0,654 extra deaths per million.
For states which did not implement SIPO, we calculate <strong>the</strong> number <strong>of</strong> deaths with SIPO as <strong>the</strong>
number <strong>of</strong> <strong>of</strong>ficial COVID-19 deaths 14 days after March 31 2020 plus 0,654 extra deaths per million.
We use March 31 2020 as this was <strong>the</strong> average date on which SIPO was implemented in <strong>the</strong> 40 states
which did implement SIPO. Using this approximation, <strong>the</strong> effect <strong>of</strong> SIPO's in <strong>the</strong> U.S. is 1,1% more
deaths after 14 days. Common st<strong>and</strong>ard errors are not available.
We use estimates from Table 2 (four weeks). Common estimate is calculated as <strong>the</strong> average <strong>of</strong> <strong>the</strong>
effect in Europe <strong>and</strong> United States, where <strong>the</strong> effect for each is calculated as (ln(policy stringency) -
ln(recommendation stringency)) x estimate.
The study is not included in <strong>the</strong> meta-analysis, as it looks at <strong>the</strong> effect <strong>of</strong> NPIs on growth rates <strong>and</strong>
does not include an estimate <strong>of</strong> <strong>the</strong> effect on total mortality.
8-Jun-20 0 Find that, world-wide, internal NPIs have prevented about 650,000 deaths (3.11 deaths were
prevented for each death that occurred, i.e. 76% effect). However, this effect is for any lockdown
including a Swedish lockdown. They do not find an extra effect <strong>of</strong> stricter lockdowns <strong>and</strong> state that
“our results point to <strong>the</strong> fact that people might adjust <strong>the</strong>ir behaviors quite significantly as partial
measures are implemented, which might be enough to stop <strong>the</strong> spread <strong>of</strong> <strong>the</strong> virus.” Hence, whe<strong>the</strong>r
<strong>the</strong> baseline is Sweden, which implemented a ban on large ga<strong>the</strong>rings early in <strong>the</strong> p<strong>and</strong>emic, or <strong>the</strong>
baseline is “doing nothing” can affect <strong>the</strong> magnitude <strong>of</strong> <strong>the</strong> estimated impacts. Since all Western
countries did something <strong>and</strong> estimates in o<strong>the</strong>r reviewed studies are relative to doing less – <strong>and</strong>,
hence not to doing nothing, we report <strong>the</strong> result from Bonardi et al. as compared to “doing less.”
Hence, for Bonardi et al. we use 0% as <strong>the</strong> common estimate in <strong>the</strong> meta-analysis for each NPI (SIPO,
regional lockdown, partial lockdown, <strong>and</strong> border closure (stage 1, stage 2 <strong>and</strong> full) because all NPIs are
insignificant (compared to Sweden’s “doing <strong>the</strong> least”-lockdown).
14-May-
21
1-Aug-20
1-Jan-21
10-Mar-
21
3-Aug-20
PLOS ONE
EClinacal-
Medicine
Journal <strong>of</strong>
Econometric
s
MDPI
Economic
Inpuiry
Business shutdown saved 9,439 Italian lives by 13th 2020. This corresponds to 32%, as <strong>the</strong>re were
20,465 COVID-19-deaths in Italy by mid April 2020.
Finds no effect <strong>of</strong> partial border closure, complete border closure, partial lockdown (physical
distancing measures only), complete lockdown (enhanced containment measures including suspension
<strong>of</strong> all non-essential services), <strong>and</strong> curfews. In <strong>the</strong> meta-analysis we use a common estimate <strong>of</strong> 0%, as
estimates <strong>and</strong> st<strong>and</strong>ard errors are not available.
The study looks at <strong>the</strong> effect <strong>of</strong> NPIs on growth rates but does include an estimate <strong>of</strong> <strong>the</strong> effect on
total mortality at <strong>the</strong> end <strong>of</strong> <strong>the</strong> study period for employee face masks (-34%), business closure (-
29%). <strong>and</strong> SIPO (-18%), but not for school closures (which we <strong>the</strong>refore exclude). In reporting <strong>the</strong>
results <strong>of</strong> <strong>the</strong>ir counterfactual, <strong>the</strong>y alter between "fewer deaths with NPI" <strong>and</strong> "more deaths without
NPI.” We have converted <strong>the</strong> latter to <strong>the</strong> former as estimate/(1+estimate) so "without business
closures deaths would be about 40% higher" corresponds to "with business closures deaths would be
about 29% lower.”
The common estimate is <strong>the</strong> average effect in Europe <strong>and</strong> United States respectively calculated as
(Actual COVID-19 mortality) / (COVID-19 mortality with recommendation policy) -1, where (COVID-
19 mortality with recommendation policy) is calculated as ((Actual COVID-19 mortality) - Estimate x
Difference in stringency x population). Stringencies in Europe <strong>and</strong> United States are equal to <strong>the</strong>
average stringency from March 16th to April 15th 2020 (76 <strong>and</strong> 74 respectively) <strong>and</strong> <strong>the</strong> stringency
for <strong>the</strong> policy based solely on recommendations is 44 following Hale et al. (2020). In <strong>the</strong> meta-analysis
we use <strong>the</strong> non-linear estimate, but <strong>the</strong> squared estimate yields similar results.
The study looks at <strong>the</strong> effect <strong>of</strong> SIPO's on growth rates but does include an estimate <strong>of</strong> <strong>the</strong> effect on
total mortality after 20+ days for model 1 <strong>and</strong> 2 in Table 7. Since model 3, 4 <strong>and</strong> 5 have estimates
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