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Reference values for pulmonary function testing

Meredith C McCormack, MD, MHS
Section Editor
James K Stoller, MD, MS
Deputy Editor
Helen Hollingsworth, MD


Correct interpretation of pulmonary function tests requires the use of appropriate reference values with which the patient's results are compared [1-3]. Unlike many physiologic parameters, for which normal values do not vary with the characteristics of the particular patient, predicted values of pulmonary function depend upon age, height, gender, and race. Therefore, interpretation of pulmonary function tests performed for the first time must take these and other factors into consideration. In practice, this is usually done by a computer using linear regression equations (reference equations) for calculation of "predicted values," as determined by published studies of large numbers of healthy individuals.

Even when anthropometric factors are taken into consideration, the "normal" range for measurements of pulmonary function remains wide, often 80 to 120 percent of the predicted value. This means that large changes with disease progression or therapy can easily occur while the patient's values remain within the normal range. Therefore, follow-up pulmonary function tests in adults should be compared with the patient's previous (baseline) values, not the predicted values.

With children, the normal growth of lung function is fast when compared to the changes observed with disease or therapy. As a result, the use of growth charts (looking for trends across percentile lines) most accurately reflects changes that cannot be attributed to growth (figure 1A-B).

The American Thoracic Society (ATS) statement on the standardization of spirometry, as well as other ATS guidelines, can be accessed through the ATS web site at www.thoracic.org/statements.


During childhood, the lungs grow in proportion to the increase in height. This growth results in an exponential increase in lung volumes (and maximal flows) with each year from preschool age through adolescence [4]. On average, girls reach both their maximal height and their maximal lung volume earlier than boys, but boys achieve larger lung volumes. Additional factors may affect maximal lung function:


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Literature review current through: Sep 2016. | This topic last updated: May 2, 2014.
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  1. Miller MR, Hankinson J, Brusasco V, et al. Standardisation of spirometry. Eur Respir J 2005; 26:319.
  2. Hankinson JL, Odencrantz JR, Fedan KB. Spirometric reference values from a sample of the general U.S. population. Am J Respir Crit Care Med 1999; 159:179.
  3. Pellegrino R, Viegi G, Brusasco V, et al. Interpretative strategies for lung function tests. Eur Respir J 2005; 26:948.
  4. Wang X, Dockery DW, Wypij D, et al. Pulmonary function between 6 and 18 years of age. Pediatr Pulmonol 1993; 15:75.
  5. Robbins DR, Enright PL, Sherrill DL. Lung function development in young adults: is there a plateau phase? Eur Respir J 1995; 8:768.
  6. Korotzer B, Ong S, Hansen JE. Ethnic differences in pulmonary function in healthy nonsmoking Asian-Americans and European-Americans. Am J Respir Crit Care Med 2000; 161:1101.
  7. Babb TG, Wyrick BL, DeLorey DS, et al. Fat distribution and end-expiratory lung volume in lean and obese men and women. Chest 2008; 134:704.
  8. Sutherland TJ, Goulding A, Grant AM, et al. The effect of adiposity measured by dual-energy X-ray absorptiometry on lung function. Eur Respir J 2008; 32:85.
  9. Nides M, Rand C, Dolce J, et al. Weight gain as a function of smoking cessation and 2-mg nicotine gum use among middle-aged smokers with mild lung impairment in the first 2 years of the Lung Health Study. Health Psychol 1994; 13:354.
  10. Stanojevic S, Wade A, Stocks J, et al. Reference ranges for spirometry across all ages: a new approach. Am J Respir Crit Care Med 2008; 177:253.
  11. Quanjer PH, Stanojevic S, Cole TJ, et al. Multi-ethnic reference values for spirometry for the 3-95-yr age range: the global lung function 2012 equations. Eur Respir J 2012; 40:1324.
  12. Garcia-Rio F, Dorgham A, Pino JM, et al. Lung volume reference values for women and men 65 to 85 years of age. Am J Respir Crit Care Med 2009; 180:1083.
  13. Enright PL, Kronmal RA, Higgins M, et al. Spirometry reference values for women and men 65 to 85 years of age. Cardiovascular health study. Am Rev Respir Dis 1993; 147:125.
  14. Enright PL, Kronmal RA, Manolio TA, et al. Respiratory muscle strength in the elderly. Correlates and reference values. Cardiovascular Health Study Research Group. Am J Respir Crit Care Med 1994; 149:430.
  15. McDonnell WF, Enright PL, Abbey DE, et al. Spirometric reference equations for older adults. Respir Med 1998; 92:914.
  16. Miller MR, Thinggaard M, Christensen K, et al. Best lung function equations for the very elderly selected by survival analysis. Eur Respir J 2014; 43:1338.
  17. Enright PL, Sherrill DL. Reference equations for the six-minute walk in healthy adults. Am J Respir Crit Care Med 1998; 158:1384.
  18. ATS Committee on Proficiency Standards for Clinical Pulmonary Function Laboratories. ATS statement: guidelines for the six-minute walk test. Am J Respir Crit Care Med 2002; 166:111.
  19. Cerveri I, Corsico AG, Accordini S, et al. Underestimation of airflow obstruction among young adults using FEV1/FVC <70% as a fixed cut-off: a longitudinal evaluation of clinical and functional outcomes. Thorax 2008; 63:1040.