Inclusion Criteria and Study Selection
Two investigators (W.Q. and W.Z.Y.) selected the studies based on the following inclusion criteria: (1) participants: adults with acute stroke diagnosed by computed tomography (CT) or magnetic resonance imaging (MRI) and without infection; (2) interventions: prophylactic antibiotics in addition to conventional treatment within seven days of the onset of acute stroke, irrespective of the type, dosage, and route of administration; (3) comparisons: placebo or no treatment in addition to conventional treatments; (4) outcomes: the primary outcomes were mortality rate, pneumonia and the secondary outcomes included incidence of infections (including pneumonia, urinary tract infections, catheter-related phlebitis, other or unclear origin infections), urinary tract infections, length of hospital stay, National Institute of Health stroke scale (NIHSS) score, Functional Independence (FI, defined as the proportion of patients with a mRS score of ≤ 2), and adverse events; (5) studies: RCTs. The studies were excluded if they were conference abstracts or duplicate publications, and publications in a language other than English and Chinese. We performed a preliminary screening by screening the title and abstract and a second screening by retrieving the full text for further evaluation to determine whether it was finally included.