Reliability of external impulse oscillometry reference values for assessing respiratory health in Swedish adults.

Impulse oscillometry (IOS) can be used to assess the mechanical properties of the respiratory airways. The method is easy to perform as it requires only tidal breathing and may provide complimentary information beyond that from dynamic spirometry. For the method to be clinically useful, reference values appropriate with regard to methodology and population are needed. The IOS equipment producer recommended reference values are derived from a German population[1], while method specific reference values for healthy non-smoking adult Caucasian are available from smaller datasets from Europe[2] and Australia[3].