An audit of pulmonary function laboratories in the West Midlands

Area of Science:

• Pulmonary Medicine
• Diagnostic Testing
• Medical Laboratory Science

Background:

• Pulmonary function testing (PFT) is crucial for diagnosing and managing respiratory diseases.
• Laboratory results can be influenced by various external factors.
• Variability in PFT results among laboratories necessitates quality assessment.

Purpose of the Study:

• To assess the extent of variation in PFT results across laboratories in the West Midlands.
• To identify potential causes contributing to observed variations in PFT outcomes.

Main Methods:

• Phase 1 involved three healthy subjects undergoing PFTs at 22 West Midlands laboratories, with data collected on technician qualifications, training, protocols, and equipment.
• Phase 2 required all 22 laboratories to calculate predicted PFT values using standardized demographic data sets.
• Technical aspects, including volume and gas analyzer calibration, were investigated using standard gases.

Main Results:

• Significant variations (P < 0.05) were found in measured PFT values for all subjects across laboratories.
• Significant variations (P < 0.05) were observed in predicted PFT values, excluding total lung capacity.
• Laboratories showed significant differences (P < 0.05) in calculating predicted PFT values, while volume and gas analyzer measurements showed no significant differences.

Conclusions:

• Substantial variability exists in PFT results and predicted value calculations among laboratories.
• The findings highlight a need for improved standardization and quality control in PFT procedures.
• Further investigation into specific protocols and technician training may be warranted to reduce diagnostic variability.