What do systematic reviews say?

SII‐ChAdOx1 – Serum Institute of India/AstraZeneca + University of Oxford vs ChAdOx1 – University of Oxford

SII‐ChAdOx1 – Serum Institute of India/AstraZeneca + University of… probably leads to lower systemic reactogenicity eventsb compared with chAdOx1 – University of Oxford (moderate certainty).

• Efficacy and safety of COVID‐19 vaccines 2022 · Cochrane Headline outcomes only
  RR 0.73 [0.54, 0.98]
  1 study · 400 participants
  Moderate