Common use of Spirometry Clause in Contracts

Spirometry. Spirometry included forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), FEV1/FVC ratio and maximum expiratory flow at 50% of FVC (MEF50). Bronchodilator response was not assessed. Spirometry was performed on the same day as the screening CTand was repeated after 3 years of follow-up. All participants with an FEV1/FVC ratio <70% at baseline were considered to have airflow obstruction. Statistical evaluation Mean and SD values were calculated for normally distributed data and median and IQR for non-normally distributed data. The Student t test and c2 test were used to detect differences between groups as appropriate. ▇▇▇▇▇▇▇ correlations were used to establish associations between normally distributed variables at baseline. — Previous research has shown that lung function decline is linear over a time span of 3 years.20 FEV1, FEV1/FVC and MEF50 values over time were therefore analysed using random inter- cept, random slope linear mixed model analysis. The time of observation/intercept was chosen as random parameters; all other parameters were considered to be fixed. The choice of the covariance matrix fell on the unstructured one, based on a comparison of the 2 restricted log likelihood values. The results of the analyses for FEV1/FVC and MEF50 are shown in the online supplement. The baseline low-attenuation area at CT (Perc15) was the main explanatory factor. We adjusted for pack- years smoked, smoking status, centre, height, body mass index and age to obtain corrected lung function parameters. We inserted interactions between Perc15 and absence/presence of airflow obstruction, between Perc15 and smoking status and between Perc15 and pack-years to test whether the association between Perc15 and lung function decline was also dependent on the presence of baseline obstruction or on exposure to tobacco.21 Decline in lung function was calculated by subtracting corrected — =