Nonsmokers | Smokers | |

Total events n | 411 | 59 |

Positive cases n | 197 | 15 |

Prevalence | 48 | 25 |

Cut-off ppb | 50 | 25 |

Sensitivity | 72 | 66 |

Specificity | 56 | 48 |

PPV | 61 | 30 |

NPV | 68 | 81 |

Accuracy | 64 | 53 |

p-value^{#} | <0.001 | 0.39 |

Data are presented as %, unless otherwise indicated. PPV: positive predictive value; NPV: negative predictive value.

^{#}: the p-value was defined as the statistical significance of rejecting an area under the curve of 0.5. A positive event was defined as controlled asthma (Asthma Control Questionnaire score <1.5). A true-positive case was defined as an exhaled nitric oxide fraction (*F*_{eNO}) of less than or the same as the cut-off value associated with a controlled asthma.*F*_{eNO}does not discriminate for or against cross-sectionally controlled*versus*uncontrolled asthma in smoking patients (pā=ā0.39).