Value predictors of a poor prognosis | |

Distance m | ≤334 |

6MWspeed m·s^{−1} | ≤0.8 |

6MWW m·kg^{−1} | ≤20 000 |

DSP %·m | ≤290 |

6MWspeed: calculated by dividing the 6-min walk distance by the total walking time; 6MWW: 6-min walking work, the product of the 6-min walking distance and the patient weight; DSP: distance saturation product, the product of the 6-min walk distance and the lowest registered arterial oxygen saturation measured by pulse oximetry.