Frequency of adverse events in the placebo arms of COVID-19 vaccine trials: a systematic review and meta-analysis
Importance Adverse events (AEs) after placebo treatment are common in randomized
clinical drug trials. Systematic evidence regarding these nocebo responses in vaccine trials
is important for COVID-19 vaccination worldwide especially because concern about AEs is
reported to be a reason for vaccination hesitancy. Objective To compare the frequencies of
AEs reported in the placebo groups of COVID-19 vaccine trials with those reported in the
vaccine groups. Data Sources For this systematic review and meta-analysis, the Medline …
clinical drug trials. Systematic evidence regarding these nocebo responses in vaccine trials
is important for COVID-19 vaccination worldwide especially because concern about AEs is
reported to be a reason for vaccination hesitancy. Objective To compare the frequencies of
AEs reported in the placebo groups of COVID-19 vaccine trials with those reported in the
vaccine groups. Data Sources For this systematic review and meta-analysis, the Medline …