3.5. Risk of publication bias
The
funnel plots of fever, cough, positive CT findings and coexisting
disorders are symmetric, which meant that these indicators may not be
published biased. On the contrary, the funnel plots of severe case or
death, lymphopenia, preterm labor, cesarean section, fetal distress,
neonatal asphyxia or neonatal death or stillbirth and neonatal infection
are asymmetric, which meant that the indicators above may have
publication bias. Since there was only 1 article about SARS-CoV-2 test
of breast milk, it was meaningless to draw a funnel plot. Therefore, the
publication bias of it was not evaluated. The funnel plots of fever and
cough are shown in Figure S1 and Figure S2.