Respiratory flow-volume loop
I understand almost all of the concepts discussed in flow-volume loop, except for one, which is PEFR (Peak expiratory flow rate).
According to UWorld, PEFR increases in restrictive lung disease. That's because 1) The increase in elastic recoil lead to decreased compliance, and 2) Increased radial traction on airways by fibrotic lung. That makes sense, but what doesn't -at least to me- is the diagram shown by UWorld, where it shows the PEFR clearly decreased -instead of increased- in restrictive lung disease. First Aid seems to agree with UWorld regarding the diagram, but it didn't comment on PEFR at all or even mention it. After searching the internet, I found so much conflicts between different websites (see images below), and I ended up more confused than when I started. Any help would be appreciated. Thanks in advance.