Abstract
Objective: To investigate the validity of spirometric tests performed in general practice.
Method: A repeated within subject comparison of spirometric tests with a "gold standard" (spirometric tests performed in a pulmonary function laboratory) was performed in 388 subjects with chronic obstructive pulmonary disease (COPD) from 61 general practices and four laboratories. General practitioners and practice assistants undertook a spirometry training programme. Within subject differences in forced expiratory volume in 1 second and forced vital capacity (ΔFEV1 and ΔFVC) between laboratory and general practice tests were measured (practice minus laboratory value). The proportion of tests with FEV1 reproducibility <5% or <200 ml served as a quality marker.
Results: Mean ΔFEV1 was 0.069 l (95% CI 0.054 to 0.084) and ΔFVC 0.081 l (95% CI 0.053 to 0.109) in the first year evaluation, indicating consistently higher values for general practice measurements. Second year results were similar. Laboratory and general practice FEV1 values differed by up to 0.5 l, FVC values by up to 1.0 l. The proportion of non-reproducible tests was 16% for laboratory tests and 18% for general practice tests (p=0.302) in the first year, and 18% for both in the second year evaluation (p=1.000).
Conclusions: Relevant spirometric indices measured by trained general practice staff were marginally but statistically significantly higher than those measured in pulmonary function laboratories. Because of the limited agreement between laboratory and general practice values, use of these measurements interchangeably should probably be avoided. With sufficient training of practice staff the current practice of performing spirometric tests in the primary care setting seems justifiable.
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Selected References
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- Bland J. M., Altman D. G. Statistical methods for assessing agreement between two methods of clinical measurement. Lancet. 1986 Feb 8;1(8476):307–310. [PubMed] [Google Scholar]
- Borsboom G. J., van Pelt W., van Houwelingen H. C., van Vianen B. G., Schouten J. P., Quanjer P. H. Diurnal variation in lung function in subgroups from two Dutch populations: consequences for longitudinal analysis. Am J Respir Crit Care Med. 1999 Apr;159(4 Pt 1):1163–1171. doi: 10.1164/ajrccm.159.4.9703106. [DOI] [PubMed] [Google Scholar]
- Dirksen A., Madsen F., Pedersen O. F., Vedel A. M., Kok-Jensen A. Long-term performance of a hand held spirometer. Thorax. 1996 Oct;51(10):973–976. doi: 10.1136/thx.51.10.973. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Dowson L. J., Mushtaq M., Watts T., Shurvinton J., Gooch R., Hayton R., Jones J. M., Perks W. H. A re-audit of pulmonary function laboratories in the West Midlands. Respir Med. 1998 Sep;92(9):1155–1162. doi: 10.1016/s0954-6111(98)90411-5. [DOI] [PubMed] [Google Scholar]
- Eaton T., Withy S., Garrett J. E., Mercer J., Whitlock R. M., Rea H. H. Spirometry in primary care practice: the importance of quality assurance and the impact of spirometry workshops. Chest. 1999 Aug;116(2):416–423. doi: 10.1378/chest.116.2.416. [DOI] [PubMed] [Google Scholar]
- Enright P. L., Connett J. E., Kanner R. E., Johnson L. R., Lee W. W. Spirometry in the Lung Health Study: II. Determinants of short-term intraindividual variability. Am J Respir Crit Care Med. 1995 Feb;151(2 Pt 1):406–411. doi: 10.1164/ajrccm.151.2.7842199. [DOI] [PubMed] [Google Scholar]
- Ferguson G. T., Enright P. L., Buist A. S., Higgins M. W. Office spirometry for lung health assessment in adults: A consensus statement from the National Lung Health Education Program. Chest. 2000 Apr;117(4):1146–1161. doi: 10.1378/chest.117.4.1146. [DOI] [PubMed] [Google Scholar]
- Griffiths C., Feder G., Wedzicha J., Foster G., Livingstone A., Marlowe G. S. Feasibility of spirometry and reversibility testing for the identification of patients with chronic obstructive pulmonary disease on asthma registers in general practice. Respir Med. 1999 Dec;93(12):903–908. doi: 10.1016/s0954-6111(99)90057-4. [DOI] [PubMed] [Google Scholar]
- Knottnerus J. André, van Weel Chris, Muris Jean W. M. Evaluation of diagnostic procedures. BMJ. 2002 Feb 23;324(7335):477–480. doi: 10.1136/bmj.324.7335.477. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Madsen F., Ulrik C. S., Dirksen A., Hansen K. K., Nielsen N. H., Frølund L., Viskum K., Kok-Jensen A. Patient-administered sequential spirometry in healthy volunteers and patients with alpha 1-antitrypsin deficiency. Respir Med. 1996 Mar;90(3):131–138. doi: 10.1016/s0954-6111(96)90154-7. [DOI] [PubMed] [Google Scholar]
- Pauwels R. A., Buist A. S., Calverley P. M., Jenkins C. R., Hurd S. S., GOLD Scientific Committee Global strategy for the diagnosis, management, and prevention of chronic obstructive pulmonary disease. NHLBI/WHO Global Initiative for Chronic Obstructive Lung Disease (GOLD) Workshop summary. Am J Respir Crit Care Med. 2001 Apr;163(5):1256–1276. doi: 10.1164/ajrccm.163.5.2101039. [DOI] [PubMed] [Google Scholar]
- Rebuck D. A., Hanania N. A., D'Urzo A. D., Chapman K. R. The accuracy of a handheld portable spirometer. Chest. 1996 Jan;109(1):152–157. doi: 10.1378/chest.109.1.152. [DOI] [PubMed] [Google Scholar]
- Siafakas N. M., Vermeire P., Pride N. B., Paoletti P., Gibson J., Howard P., Yernault J. C., Decramer M., Higenbottam T., Postma D. S. Optimal assessment and management of chronic obstructive pulmonary disease (COPD). The European Respiratory Society Task Force. Eur Respir J. 1995 Aug;8(8):1398–1420. doi: 10.1183/09031936.95.08081398. [DOI] [PubMed] [Google Scholar]
- Spann S. J. Impact of spirometry on the management of chronic obstructive airway disease. J Fam Pract. 1983 Feb;16(2):271–275. [PubMed] [Google Scholar]
- van den Boom G., van Schayck C. P., van Möllen M. P., Tirimanna P. R., den Otter J. J., van Grunsven P. M., Buitendijk M. J., van Herwaarden C. L., van Weel C. Active detection of chronic obstructive pulmonary disease and asthma in the general population. Results and economic consequences of the DIMCA program. Am J Respir Crit Care Med. 1998 Dec;158(6):1730–1738. doi: 10.1164/ajrccm.158.6.9709003. [DOI] [PubMed] [Google Scholar]