[IMJ On-Air] Race-neutral equations for classification of lung function

Spirometry reference equations are central to differentiating obstructive ventilatory defects, like asthma and bronchiectasis from restrictive ventilatory defects, like sarcoidosis and idiopathic pulmonary fibrosis. Across the population, the metrics of lung function testing fall out on a bell-curve, and a person’s predicted score if health can be determined by putting their sex, age and height into a reference equation.

The shape of this bell curve does change from one population group to the next and it was classically thought that the ethnicity was an important driver in this. As such, race-specific equations were developed to provide an adjusted reference value appropriate to the individual patient. In recent years, however, it has been questioned whether ethnicity and genetics are as much a driver as are structural differences in exposure to modifiable factors. 

In a paper published in the RACP’s Internal Medicine Journal, researchers asked what effect it would have on an Australian patient cohort if diagnostic classification of chronic respiratory diseases was done using race-neutral equations of lung function instead. 

Key Reference
Implications of race-neutral equations on interpretation of lung function in Australia [Intern Med J. 2026]

Guests
Dr Daniel Tan PhD (Royal Melbourne Hospital; Monash Health; University of Melbourne)
Dr Helen Luo (Monash Health)
Professor Paul King FRACP PhD (Monash Health; Monash University)
 
Production
Written and produced by Mic Cavazzini DPhil. Music licenced from Epidemic Sound ‘Tree Tops’ by Autohacker and ‘Fugent’ by Lupus Nocte. Image created and copyrighted by RACP. 

Visit the Pomegranate Health web page for a transcript and supporting references. Add educational activity to MyCPD. Subscribe through any podcasting app or our email alerts list.