Participant Preparation, Screening, and Test Safety
Participant Preparation, Screening, and Test Safety
This domain tests the pre-test checklist that protects the participant and prevents avoidable artifacts.
Core rules
- Obtain informed consent and explain the maneuver with a demonstration.
- Screen for contraindications and acute illness; ask about chest pain, recent surgery, pneumothorax, and pregnancy-related discomfort.
- Record age, sex, ethnicity, height without shoes (to 0.5 cm), and weight; these drive predicted values.
- Prepare the participant: loosen tight clothing, remove gum, use a nose clip, sit upright or stand, and rest 5 minutes.
- Withhold bronchodilators per protocol: short-acting beta-agonist 4–6 h, ipratropium 6 h, long-acting beta-agonist 12 h, tiotropium 24 h. Avoid smoking for 1 h, alcohol for 4 h, vigorous exercise for 30 min, and a heavy meal for 2 h.
- Position the mouthpiece so lips seal; support dentures if they are loose.
Worked example
A participant arrives 30 minutes after a vigorous gym session and reports wheezing. Reasoning: exercise within 30 minutes can alter FEV1 and increase bronchospasm risk. Rest, reassess symptoms, document the exercise, and test only when the participant is stable; note the timing in the record.
Traps
- Measuring height with shoes or estimating it from self-report.
- Skipping the nose clip and later accepting a leaking curve.
- Failing to document medication withholding, making a negative bronchodilator response uninterpretable.