Background: Spirometry is the most common pulmonary function test. It is widely used in the assessment of lung function to provide objective information used in the diagnosis of lung diseases and monitoring lung health. In 2005, the American Thoracic Society and the European Respiratory Society jointly adopted technical standards for conducting spirometry. Improvements in instrumentation and computational capabilities, together with new research studies and enhanced quality assurance approaches, have led to the need to update the 2005 technical standards for spirometry to take full advantage of current technical capabilities. Methods: This spirometry technical standards document was developed by an international joint task force, appointed by the American Thoracic Society and the European Respiratory Society, with expertise in conducting and analyzing pulmonary function tests, laboratory quality assurance, and developing international standards. A comprehensive review of published evidence was performed. A patient survey was developed to capture patients’ experiences. Results: Revisions to the 2005 technical standards for spirometry were made, including the addition of factors that were not previously considered. Evidence to support the revisions was cited when applicable. The experience and expertise of task force members were used to develop recommended best practices. Conclusions: Standards and consensus recommendations are presented for manufacturers, clinicians, operators, and researchers with the aims of increasing the accuracy, precision, and quality of spirometric measurements and improving the patient experience. A comprehensive guide to aid in the implementation of these standards was developed as an online supplement.

This document provides an update to the European Respiratory Society (ERS)/American Thoracic Society (ATS) technical standards for single-breath carbon monoxide uptake in the lung that was last updated in 2005. Although both D (diffusing capacity) and T (transfer factor) are valid terms to describe the uptake of carbon monoxide in the lung, the term D is used in this document. A joint taskforce appointed by the ERS and ATS reviewed the recent literature on the measurement of D and surveyed the current technical capabilities of instrumentation being manufactured around the world. The recommendations in this document represent the consensus of the taskforce members in regard to the evidence available for various aspects of D measurement. Furthermore, it reflects the expert opinion of the taskforce members on areas in which peer-reviewed evidence was either not available or was incomplete. The major changes in these technical standards relate to D measurement with systems using rapidly responding gas analysers for carbon monoxide and the tracer gas, which are now the most common type of D instrumentation being manufactured. Technical improvements and the increased capability afforded by these new systems permit enhanced measurement of D and the opportunity to include other optional measures of lung function.

There are numerous reference equations available for the single-breath transfer factor of the lung for carbon monoxide (); however, it is not always clear which reference set should be used in clinical practice. The aim of the study was to develop the Global Lung Function Initiative (GLI) all-age reference values for Data from 19 centres in 14 countries were collected to define reference values. Similar to the GLI spirometry project, reference values were derived using the LMS (lambda, mu, sigma) method and the GAMLSS (generalised additive models for location, scale and shape) programme in R.12 660 measurements from asymptomatic, lifetime nonsmokers were submitted; 85% of the submitted data were from Caucasians. All data were uncorrected for haemoglobin concentration. Following adjustments for elevation above sea level, gas concentration and assumptions used for calculating the anatomic dead space volume, there was a high degree of overlap between the datasets. Reference values for Caucasians aged 5-85 years were derived for, transfer coefficient of the lung for carbon monoxide and alveolar volume.This is the largest collection of normative data, and the first global reference values available for.

The committee believes that wide adoption of these formats and their underlying principles by equipment manufacturers and pulmonary function laboratories can improve the interpretation, communication, and understanding of test results.

The Global Lung Function Initiative (GLI) Network has become the largest resource for reference values for routine lung function testing ever assembled. This article addresses how the GLI Network came about, why it is important, and its current challenges and future directions. It is an extension of an article published in Breathe in 2013 [1], and summarises recent developments and the future of the GLI Network.Key pointsThe Global Lung Function Initiative (GLI) Network was established as a result of international collaboration, and altruism between researchers, clinicians and industry partners. The ongoing success of the GLI relies on network members continuing to work together to further improve how lung function is reported and interpreted across all age groups around the world.The GLI Network has produced standardised lung function reference values for spirometry and gas transfer tests.GLI reference equations should be adopted immediately for spirometry and gas transfer by clinicians and physiologists worldwide.The recently established GLI data repository will allow ongoing development and evaluation of reference values, and will offer opportunities for novel research.Educational aimsTo highlight the advances made by the GLI Network during the past 5 years.To highlight the importance of using GLI reference values for routine lung function testing (e.g. spirometry and gas transfer tests).To discuss the challenges that remain for developing and improving reference values for lung function tests.