The relationship between body mass index and bronchial hyperresponsiveness showing the mediating effect of airway closure (percentage change in forced vital capacity (FVC) from baseline to the end of the methacholine challenge)
| Coefficient | Standard error | p-value | 95% CI | |
| Indirect effect | 0.0741 | 0.0301 | 0.014 | 0.0152–0.1331 |
| Direct effect | 0.0983 | 0.0434 | 0.024 | 0.0132–0.1833 |
| Total effect | 0.1724 | 0.0554 | 0.002 | 0.0638–0.2810 |
Model adjusted for baseline forced expiratory volume in 1 s to FVC ratio, asthma status, socioeconomic status, sex and smoking.