Spirometry in biracial children: how adequate are race-based reference equations?

S pirometric reference equations are typically stratified by race because of racial differences in lung function, particularly between black and white individuals, at least in part because of black individuals having a smaller thorax to leg length ratio, and thus smaller lung volumes for a given height, than white individuals. Use of race-based pulmonary function equations is especially problematic in biracial/multiracial individuals, who compose an increasing portion of the US population, as lung physiology may not simply be an average of their composite races; use of race in pulmonary function testing has recently been questioned. To our knowledge, no spirometric reference equations exist for biracial or multiracial individuals. We assessed pulmonary function in biracial (black and white) children and compared spirometric data when children were classified as being black vs white.