Dear Ali, 

Comparisons between the methods:

Article An impulse oscillometry system is less efficient than spirom...

Article Impulse oscillometry in acute and stable asthmatic children:...

Dear Ali,

The biggest clinical benefit of IOS over spirometry is that it is effort independent, and so the results are not confounded by the patient being tired or not engaging fully with testing.

Kind regards

Tom

 Dear Béatrice and Thomas,

Thank you so much for your answers and valuable articles!!

Regards,

Here is a useful review on impulse oscillometry.  Although effort independent, some cooperation is still required in performing impulse oscillometry.  On a practical level, spirometry interpretation tends to be more straightforward.  Impulse oscillometry has been hypothesized to be more sensitive for small airway diseases, for which spirometry seems to be relatively insensitive at diagnosing.   

http://journal.publications.chestnet.org/article.aspx?articleid=1900866&resultClick=3

Dear All,

Although IOS is more sensitive for small airway obstruction than PFT, it is not specific, and cannot be used for diagnosis. Its value is also unclear in the follow up of patients.  However it has some (not fully explored) value in BHR and BDR tests, as we see that there are patients whose response can be detected only with IOS and exhibit only a partial or no response with PFT.

Other areas where IOS has some potential value:

-Pediatric populations who cannot reliably perform PFT

-During general anesthesia (more studies are needed).

-Animal studies.

try to access:

J Invest Allergol Clin Immunol 2005; Vol. 15(2): 102-106

"IOS was well accepted by young asthmatic children and provided reproducible and sensitive indices of lung function"