Nine studies were included (1,101 patients), of which 6 included PEFR as an outcome measure (836 patients).
The overall summary effect size, when comparing antibiotics with placebo was 0.22 (95% confidence interval, CI: 0.10, 0.34, p < 0.05) indicating a benefit to the antibiotic-treated group.
The summary effect size for changes in PEFR was 0.19 (95% CI: 0.03, 0.35, p < 0.05) in favour of the antibiotic group. This translates to a difference in PEFR of 10.75 L/min (95% CI: 4.96, 16.54).
Subanalyses of out- and in-patient data gave effect sizes of only 0.17 (95% CI: 0.03, 0.30, p < 0.05) and 0.38 (95% CI: 0.13, 0.62, p < 0.05), respectively.
No significant heterogeneity was observed.