Unfortunately, the text concerning the statements of interest for this manuscript's authors was presented incorrectly. The second “SUPPORT STATEMENT” heading in the manuscript should have read “STATEMENTS OF INTEREST”. The text under this heading should have appeared as “Statements of interest for J. Stolk, J.H.C. Reiber, K.F. Rabe and B.C. Stoel can be found at www. erj.ersjournals.com/misc/statements.shtml”.
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