Exacerbation rate patient^{−1}·year^{−1#} | Rate ratio (95% CI) | Effect size^{#} | |||

Erdosteine^{¶} | Placebo^{+} | Difference versus placebo % | p-value^{§} | ||

Overall | 0.91 | 1.13 | 0.81 (0.68–0.92) | −19.4 | 0.01 |

ICS use | 0.93 | 1.16 | 0.80 (0.67–0.94) | −19.5 | 0.02 |

No ICS use | 0.89 | 1.10 | 0.81 (0.65–0.93) | −19.3 | 0.01 |

ICS: inhaled corticosteroid. ^{#}: Poisson regression estimates; ^{¶}: n=215; ^{+}: n=230; ^{§}: two-sided p-value for between-treatment difference (significance level <5%, Wilcoxon rank-sum test).