About the TL,CO Task Force

What is the TL,CO Task Force?

The TL,CO Task Force is a joint ATS/ERS project which proposes to build upon the success and expertise of the GLI Spirometry Task Force by expanding our work to include new reference values for the measurement of the transfer factor for carbon monoxide of the lung (TL,CO).

Why do we need TL,CO reference equations?

The 2005 ATS/ERS PFT guidelines provided updated standards for the measurement of TL,CO and an interpretation flow-chart showing the vital importance of TL,CO for interpreting PFTs. At this time no consensus was reached regarding which equations should be recommended. The development of international measurement standards, with corresponding changes in equipment, software and measurement techniques, combined with shifts in population characteristics, means that some TL,CO equations may no longer be appropriate. The use of inappropriate reference equations can lead to serious diagnostic errors, with its associated burden in terms of financial and human costs.

Members of the GLI TL,CO Task Force:

  • Prof Graham Hall (Perth, Australia) ERS Chair
  • Prof Brian Graham (Saskatoon, Canada) ATS Chair
  • Prof Bruce Thompson (Melbourne, Australia)
  • Prof Bruce Culver (Seattle, USA)
  • Prof Paul Enright (Tucson, USA)
  • Dr. Sanja Stanojevic (Toronto, Canada)
  • Dr. Brendan Cooper (Birmingham, UK)
  • Prof Janet Stocks (London, UK)

How to contribute data:

If you have measured TL,CO in more than 100 healthy subjects please consider contributing your data to the GLI TL,CO Task Force. To contribute data please visit http://www.gligastransfer.org.au/ to register your data for the TL,CO project. A member of the task force will contact you with further details.

Data Sharing Statutes:

To review the statutes and data sharing agreement please download the memorandum of understanding. GLI Task Force Memorandum:

 [+]  PDF journal article, handout or slides Global Lung Function Initiative (GLI) - Statutes: Deriving global multi-ethnic reference values for the transfer factor of carbon monoxide (TL,CO) in the lungs
Version 26 July 2013 See this session or publication
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Frequently Asked Questions:

  1. Will the new values be available for all lung function testing systems?
    Based on the experience of the GLI Spirometry reference values, most large lung function equipment manufacturers will incorporate the values in their “next version” of the software after they are published, but not necessarily as an update for older PC based systems because of software incompatibility.
  2. When should I change to the new reference values?
    The new reference values will have to be collated, reviewed, modelled, tested and piloted before being released to manufacturers and onto the internet . We don’t expect to complete this work for at least 18 months, but “pilot” testing may be possible before this.
  3. How should I change to the new reference values?
    The local implementation process needs to take several things into consideration. For example, do you want all local departments, hospital or regional health boards to adopt the new GLI TL,CO values? You may have to consider any research or clinical trials that may decide to use the previous values until the trial is complete.
  4. Will I be charged to use the new reference values?
    The GLI TL,CO reference values, like the GLI Spirometry reference values, are designed to be freely available, widely adopted and free to all who wish to use them. A free downloadable version in Excel and similar programmes is envisaged.
  5. Is the argument about the naming of TL,CO and DL,CO important?
    Whilst we all attempt to follow international guidelines, in the real world , the recommendations and nomenclature are adopted where it is feasible and rarely always in full to the letter. We have chosen to use the TL,CO name , but please do not let this stop you sending your data.