Principle variables in 6-min walk related to a poor prognosis in patients affected by idiopathic pulmonary fibrosis
| Value predictors of a poor prognosis | |
| Distance m | <250 |
| SpO2 nadir % | <88 |
| HRR bpm | <13 |
| DSP %·m | <200 |
SpO2: arterial oxygen saturation measured by pulse oximetry; HRR: heart rate recovery after 1 min following the test; DSP: distance saturation product, the product of the 6-min walk distance and the lowest registered SpO2.