Can everyone carry out lung function tests?

Among requirements for carrying out lung function tests are a quiet environment, knowledge, expertise, being experienced, and sufficient time to complete the test. Do not carry out spirometric tests if these conditions are not met.

• Test results are dependent upon subject cooperation and effort. Hence FEV1 and FVC can only be underestimated, but never overestimated. Unsatisfactory tests may therefore lead to erroneous conclusions, e.g. that the patient has airway obstruction when this is not the case, or the other way around.
• It is therefore indispensable that the patient is clearly instructed and given a demonstration of what the test entails. Also the subject should be encouraged to perform maximally during each test and if necessary reinstructed to overcome unsatisfactory manoeuvres, this takes time, patience and understanding. The test needs to be carried out in a quiet environment so as to avoid distraction.
• The person in charge should not be in a hurry and be sufficiently experienced to have the tests carried out properly. Spirometric tests before bronchodilatation take 5 minutes or more. Investigating elderly subjects usually takes more time, patience and empathy than in young adults. Testing children is even more demanding and it is important that the environment is suitable and child friendly.

Clearly spirometric tests cannot be carried out in a hurry. If spirometry is performed outside a respiratory laboratory the test needs to be performed to the same standard. The person testing needs to be well trained and supported by either an experienced doctor or other health profession with spirometry experience. If these conditions are not met it is better to have spirometric tests carried out in well-equipped laboratories with professionally trained and experienced personnel; you can then rely on the quality of both measurements and calibrations.