Objective Derive continuous prediction equations and their lower limits of normal for spirometric indices, which are applicable globally. Material Over 160,000 data points from 72 centres in 33 countries were shared with the European Respiratory Society Global Lung Function Initiative. Eliminating data that could not be used (mostly missing ethnic group, some outliers) left 97,759 records of healthy nonsmokers (55.3% females) aged 2.5–95 years. Methods Lung function data were collated, and prediction equations derived using the LMS (λ, µ, σ) method, which allows simultaneous modelling of the mean (mu), the coefficient of variation (sigma) and skewness (lambda) of a distribution family. Results After discarding 23,572 records, mostly because they could not be combined with other ethnic or geographic groups, reference equations were derived for healthy individuals from 3–95 years for Caucasians (N=57,395), African Americans (N=3,545), and North (N=4,992) and South East Asians (N=8,255). FEV1 and FVC between ethnic groups differed proportionally from that in Caucasians, such that FEV1/FVC remained virtually independent of ethnic group. For individuals not represented by these four groups, or of mixed ethnic origins, a composite equation taken as the average of the above equations is provided to facilitate interpretation until a more appropriate solution is developed. Conclusion Spirometric prediction equations for the 3–95 age range are now available that include appropriate age-dependent lower limits of normal. They can be applied globally to different ethnic groups. Additional data from the Indian subcontinent, Arab, Polynesian, Latin American countries, and Africa will further improve these equations in the future.

Field walking tests are commonly employed to evaluate exercise capacity, assess prognosis and evaluate treatment response in chronic respiratory diseases. In recent years, there has been a wealth of new literature pertinent to the conduct of the 6-min walk test (6MWT), and a growing evidence base describing the incremental and endurance shuttle walk tests (ISWT and ESWT, respectively). The aim of this document is to describe the standard operating procedures for the 6MWT, ISWT and ESWT, which can be consistently employed by clinicians and researchers.The Technical Standard was developed by a multidisciplinary and international group of clinicians and researchers with expertise in the application of field walking tests. The procedures are underpinned by a concurrent systematic review of literature relevant to measurement properties and test conduct in adults with chronic respiratory disease.Current data confirm that the 6MWT, ISWT and ESWT are valid, reliable and responsive to change with some interventions. However, results are sensitive to small changes in methodology. It is important that two tests are conducted for the 6MWT and ISWT.This Technical Standard for field walking tests reflects current evidence regarding procedures that should be used to achieve robust results. OverviewThe aim of this Technical Standard is to document the standard operating procedures for the 6-min walk test (6MWT), incremental shuttle walk test (ISWT) and endurance shuttle walk test (ESWT) in adults with chronic respiratory disease. The testing procedures were developed by a multinational and multidisciplinary group of experts in field exercise testing, informed by a systematic review of the measurement properties and interpretation of the 6MWT, ISWT and ESWT in adults with chronic respiratory disease [1].The key findings of the Technical Standard are as follows.1) The 6-min walking distance (6MWD), ISWT and ESWT demonstrate good construct validity. Strong relationships with measures of exercise performance and physical activity support their conceptualisation as tests of functional exercise performance.2) A lower 6MWD is strongly associated with increased risk of hospitalisation and mortality in people with chronic respiratory disease, with a small number of studies suggesting a similar relationship for the ISWT.3) The 6MWD, ISWT and ESWT exhibit good test-retest reliability; however, there is strong evidence of a learning effect for the 6MWT and ISWT. Two tests should be performed when the 6MWT or ISWT are used to measure change over time.4) The 6MWD, ISWT and ESWT are responsive to treatment effects in people with chronic respiratory disease; however, most studies have evaluated responsiveness to rehabilitation and fewer data are available to confirm responsiveness to other interventions.5) The 6MWD and ISWT elicit a peak oxygen uptake (V9O 2 peak) that is similar to that during a cardiopulmonary exercise test (CPET). As a result, the contraindications and precautions for field testing should be consistent with those ...

This systematic review examined the measurement properties of the 6-min walk test (6MWT), incremental shuttle walk test (ISWT) and endurance shuttle walk test (ESWT) in adults with chronic respiratory disease.Studies that report the evaluation or use of the 6MWT, ISWT or ESWT were included. We searched electronic databases for studies published between January 2000 and September 2013.The 6-min walking distance (6MWD) is a reliable measure (intra-class correlation coefficients ranged from 0.82 to 0.99 in seven studies). There is a learning effect, with greater distance walked on the second test (pooled mean improvement of 26 m in 13 studies). Reliability was similar for ISWT and ESWT, with a learning effect also evident for ISWT (pooled mean improvement of 20 m in six studies). The 6MWD correlates more strongly with peak work capacity (r50.59-0.93) and physical activity (r50.40-0.85) than with respiratory function (r50.10-0.59). Methodological factors affecting 6MWD include track length, encouragement, supplemental oxygen and walking aids. Supplemental oxygen also affects ISWT and ESWT performance. Responsiveness was moderate to high for all tests, with greater responsiveness to interventions that included exercise training.The findings of this review demonstrate that the 6MWT, ISWT and ESWT are robust tests of functional exercise capacity in adults with chronic respiratory disease. OverviewThe aim of this systematic review was to examine the measurement properties for the 6-min walk test (6MWT), incremental shuttle walk test (ISWT) and endurance shuttle walk test (ESWT) in adults with chronic respiratory disease. A companion paper describes the standard operating procedures for the tests [1]. The key findings of this systematic review are as follows.1) The 6-min walking distance (6MWD) is a valid and reliable measure of exercise capacity for people with chronic lung disease. The 6MWD correlates more strongly with measures of peak work capacity and physical activity than with respiratory function or quality of life, which supports its conceptualisation as a test of functional exercise performance.2) The ISWT offers a different protocol to the 6MWT as it is incremental and externally paced. The ISWT is a valid and reliable measure of cardiopulmonary exercise capacity in chronic obstructive pulmonary disease (COPD), where there is a strong relationship between ISWT distance and peak oxygen uptake (V9O 2 peak) or work rate on a cardiopulmonary exercise test (CPET).3) A learning effect is observed for the 6MWT and the ISWT. The second test usually is the better compared with the first, but this is inconsistent.4) The ESWT is a test of endurance capacity. It is externally paced and is performed along the same course as the ISWT. Two tests do not appear to be necessary if the second test is conducted on the same day.5) Reference equations have been proposed for the 6MWD and the ISWT. Age, height and weight are included in most equations. The influence of race and ethnicity is unclear.6) The safety profile of ...

BackgroundAppropriate interpretation of pulmonary function tests (PFTs) involves the classification of observed values as within/outside the normal range based on a reference population of healthy individuals, integrating knowledge of physiologic determinants of test results into functional classifications, and integrating patterns with other clinical data to estimate prognosis. In 2005, the American Thoracic Society and the European Respiratory Society jointly adopted technical standards for the interpretation of PFTs. We aimed to update the 2005 recommendations and incorporate evidence from recent literature to establish new standard for PFT interpretation.MethodsThis technical standards document was developed by an international joint task force, appointed by the European Respiratory Society and the American Thoracic Society with multidisciplinary expertise in conducting and interpreting pulmonary function tests, and developing international standards. A comprehensive literature review was conducted, and published evidence was reviewed.ResultsRecommendations for the choice of reference equations and limits of normal of the healthy population to identify individuals with unusually low or high results, respectively are discussed. Interpretation strategies for bronchodilator responsiveness testing, limits of natural changes over time and severity are also updated. Interpretation of measurements made by spirometry, lung volumes and gas transfer are described as they relate to underlying pathophysiology with updated classification protocols of common impairments.ConclusionsPFTs interpretation must be complemented with clinical expertise and consider the inherent biological variability of the test and the uncertainty of the test result to ensure appropriate interpretation of an individual's lung function measurements.

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.