Skip to main content
. 2018 Feb 12;13(2):e0191787. doi: 10.1371/journal.pone.0191787

Fig 3. Relationship of center-of-mass displacement to PIF/PEF ratio and PEF-PIF difference obtained during the two study phases.

Fig 3

A negative displacement indicates mucus movement towards the test lung. Dashed lines mark zero of center-of-mass displacement and the thresholds (PIF/PEF ratio < 0.9 and PEF-PIF difference > 17L/min) to facilitate comparisons between study phases. Note that only during the post-instruction phase (black circles) mucus simulant was moved outward. During the pre-instruction phase (white circles) mucus simulant was moved towards the test lung.