Quebec spirometry reference values.

Lung volumes forced expiratory flow rates and carbon monoxide diffusing cap acity (apnea) were measured in 397 non-smoking, nonatopic, asymptomatic sub jects (219 women, 178 men). The equipments and methods for measurements met the ATS criteria. The linear regression of the different variables accordi ng to age and height allowed the elaboration of a new set of predictive equ ations (Quebec). When comparing the different reference values used in Nort h America and Europe, it is found that those of Miller and associates as we ll as those recommended by the CECA provide the best description of the Que bec situation. However, we would eventually prefer rite reference values of Miller and associates over those of the CECA, because they better Sit the current ATS criteria and also provide references for smokers. Lung volumes and forced expiratory flow rates of 97 non-smoking, nonatopic, asymptomatic manual workers were measured in the same conditions and submitted to the s ame comparisons. Quebec predictive values as well as those of Miller and as sociates isolated the same individuals in the so called abnormal zone. We t herefore conclude that Quebec's standards should be preferred in the Provin ce of Quebec pulmonary function laboratories.