Wiley (No impact of NPI measures)
Results: Implementing any NPIs was associated with significant reductions in case
growth in 9 out of 10 study countries, including South Korea and Sweden that im-
plemented only lrNPIs (Spain had a nonsignificant effect). After subtracting the epi-
demic and lrNPI effects, we find no clear, significant beneficial effect of mrNPIs on
case growth in any country. In France, for example, the effect of mrNPIs was +7%
(95% CI: −5%- 19%) when compared with Sweden and+13% (−12%- 38%) when
compared with South Korea (positive means pro- contagion). The 95% confidence
intervals excluded 30% declines in all 16 comparisons and 15% declines in 11/16
comparisons.
Conclusions: While small benefits cannot be excluded, we do not find significant
benefits on case growth of more restrictive NPIs. Similar reductions in case growth
may be achievable with less- restrictive interventions