TY - JOUR T1 - Verification of equipment for measuring the diffusion capacity of the lung for carbon monoxide JF - European Respiratory Journal JO - Eur Respir J SP - 523 LP - 524 DO - 10.1183/09031936.00059109 VL - 34 IS - 2 AU - F. Madsen Y1 - 2009/08/01 UR - http://erj.ersjournals.com/content/34/2/523.abstract N2 - To the Editors: In the paper by Jensen et al. 1 and the accompanying editorial by Farré and Navajas 2 the importance of quality assurance in the respiratory physiology laboratory is highlighted. The Jensen et al. 1 study represents a tremendous and successful effort on quality assurance and quality control as part of a large clinical study. The study or probably more likely the presentation of the study by Jensen et al. 1 has a few limitations seen from a metrological point of view to which I want to draw attention. Traceability is the key stone of quality control of measurements and must be addressed in all metrological studies. Metrological traceability is a property of a measurement result relating the result to a stated metrological reference through an … ER -