BACKGROUND: The guidelines to conduct and interpret conventional pulmonary function
(PFT) tests are frequently reviewed and updated. However, the quality assurance and
quality control (QA/QC) guide-lines for respiratory oscillometry testing remain limited.
QA/QC guidelines are essential for oscillometry to be used as a diagnostic pulmonary
function test (PFT) in a clinical setting. METHODS: We developed a QA/QC protocol
shortly after oscillometry was introduced in our laboratory as part of a clinical
study. The first clinical study began after the research personnel completed 3 h of
combined didactic and hands-on training and establishment of a standard operating
protocol (SOP) for oscillometry testing. All oscillometry tests were conducted using
the initial SOP protocol from October 17, 2017, to April 6, 2018. At this time, the
first QA/QC audit took place, followed by revisions to the SOP, the addition of a
QA/QC check-list, and the development of a 12-h training program. A second audit of
oscillometry tests was conducted from April 9, 2018, to June 30, 2019. Both audits
were completed by a registered cardiopulmonary technologist from the Toronto General
Pulmonary Function Lab. RESULTS: The first audit evaluated 197 paired oscillometry-PFT
tests and found 10 tests (5.08%) to be invalid, with a coefficient of variation >
15%. The second audit examined 1,930 paired oscillometry-PFT tests; only 3 tests (0.16%)
were unacceptable, with a coefficient of variation > 15%. Improvement in QA/QC was
significantly better compared to the first audit (P < .001). CONCLUSIONS: Although
oscillometry requires minimal subject cooperation, application of the principles that
govern the conduct and application of a PFT are important for ensuring that oscillometry
testing is performed according to acceptability and reproducibility. Specifically,
the inclusion of a SOP, a proper training program, a QA/QC checklist, and regular
audits with feedback are vital to ensure that oscillometry is conducted accurately
and precisely.
