Reference values for DLCO from studies that complied with the 2005 American Thoracic Society/European Respiratory Society DLCO standards
| Author# | Year | Country | Age | Subjects |
| Thompson [129] | 2008 | Australia | 45–71 years | 498 male/474 female |
| Koopman¶ [130] | 2011 | Netherlands | 7–18 years | 278 male/265 female |
| Garcia-Rio¶ [131] | 2012 | Spain | 65–85 years | 169 male/262 female |
| Kim [132] | 2012 | USA and Australia | 5–19 years | 225 male/254 female |
| Thomas [133] | 2014 | Denmark | 5–17 years | male/female (297 total) |
| Michailopoulos [134] | 2015 | Greece | 18–91 years | 234 male/233 female |
| Verbanck [135] | 2016 | Belgium | 20–80 years | 128 male/124 female |
DLCO: diffusing capacity of the lung for carbon monoxide. #: only studies with at least 100 males and 100 females are included. All of these reference values were derived using caucasian subjects. ¶: test gas contained 19% oxygen (all other studies used test gas with 21% oxygen).