RT Journal Article SR Electronic T1 Spirometry: then and now JF Breathe JO Breathe FD European Respiratory Society SP 206 OP 216 DO 10.1183/18106838.0103.206 VO 1 IS 3 A1 G.J. Gibson YR 2005 UL http://breathe.ersjournals.com/content/1/3/206.abstract AB Key pointsThe spirometric measurements of most clinical value are FEV1 and VC.FEV1 and VC are used for diagnosis, assessment of severity, and monitoring progress and response to treatment.FEV1 and VC are a valuable guide in the prognosis of many diseases, not only respiratory.The greatest clinical value of maximum flow–volume curves is the recognition of central (upper) airway narrowing.Educational aimsTo outline the historical development and rationale of the measurements commonly made during forced expiration.To review the diagnostic specificity of these measurements and their continuing value in clinical respiratory medicine.To review the prognostic information conveyed by measurements of FEV1 and VC in various respiratory and non-respiratory diseases.Summary Measurements of VC were first made in the 18th Century, and they had been reported in large numbers of healthy subjects and patients with respiratory disease (tuberculosis) by the middle of the 19th Century. However, little use was made of the VC in clinical medicine until the second half of the 20th Century. The FEV1 was first described about 50 years ago. Although used widely by respiratory physicians, the value of both these simple measurements remains under-appreciated by non-specialists. Their main roles are in aiding diagnosis by pattern recognition, assessing severity of disease, and monitoring progress and/or the effects of treatment. The valuable prognostic information conveyed by FEV1 and VC has been demonstrated in several conditions, both respiratory and nonrespiratory.