Ten RCTs (n=1,922) were included in the review. Seven were double-blind and three were open-labelled in design.
FEV1 (3 RCTs).
Twice-daily budesonide was associated with a slightly favourable FEV1, although this was not statistically significant (SMD 0.09, 95% CI: -0.09, 0.27). No evidence of statistical heterogeneity was found (data not given).
Morning PEF (8 RCTs; 9 comparisons).
Twice-daily budesonide was associated with a slightly favourable PEF, although this was not statistically significant (SMD 0.07, 95% CI: -0.04, 0.17). No evidence of statistical heterogeneity was found (data not given).
Withdrawals due to asthma (9 RCTs; 10 comparisons).
No significant difference was found between budesonide once and twice daily on withdrawals due to asthma (OR 1, 95% CI: -0.43, 0.43). No evidence of statistical heterogeneity was found (data not given).
Secondary outcomes.
No difference was found between budesonide once and twice daily on evening PEF, or on day or night beta-agonist use (results not given).