18. The effects of cigarette smoking on maternal airway function during pregnancy were investigated by Das et al. (A-28). The subjects were women in each of the three trimesters of pregnancy. Among the data collected were the following measurements on forced vital capacity (FVC), which are shown by smoking status of the women. May we conclude, on the basis of these data, that mean FVC measurements differ according to smoking status? Let a = .01 and find the p value. Use Tukey's procedure to test for significant differences among individual pairs of sample means.

Nonsmokers Light Smokers Heavy Smokers 3.45 4.05 3.15 4.03 3.95 4.29 3.04 3.02 4.00 4.66 3.86 3.69 3.78 4.38 4.34 3.12 4.00 3.45 3.85 3.83 3.63 3.50 4.05 2.74 3.49 4.94 3.99 3.74 2.68 4.33 3.95 4.75 3.10 3.12 4.84 3.10 3.39 4.03 3.55 3.65 3.43 3.20 3.60 4.24 3.80 4.14 4.44 3.58 3.65 4.93 4.37 3.99 3.82 3.24 2.93 4.78 4.21 3.64 4.13 4.20 3.68 4.77 4.36 4.87 4.62 4.54 3.86 3.94 4.03 4.37 4.02 4.64 4.60 4.34 4.10 4.48 3.20 3.31 2.74 3.73 4.45 4.22 4.26 3.29 4.25 4.34 3.94 4.05 3.63 3.45 3.40 4.37 4.10 3.90 3.60 3.42 3.99 4.40 2.97 3.75 3.20 4.21 4.31 3.78 3.36 3.89 4.06 3.74 3.72 4.24 2.90 2.72 3.80 3.67 3.87 4.73 2.92 3.94 4.21 2.87 3.07 3.44 3.45 4.05 3.84 3.53 3.89 4.59 4.44 4.78 3.94 3.33 3.48 4.07 3.60 3.70 4.54 4.10 4.18 3.62 3.10 3.86 2.70 3.51 4.81 4.04 3.74 3.73 3.41 4.46 3.65 3.40 3.38 3.90 3.72 3.63 3.39 3.66 4.69 3.68 3.50 4.08 2.84 4.07 3.62 3.84 3.34 3.95 4.27 2.82 3.47 4.25 3.55 4.14 SOURCE: Jean-Marie Moutquin, M.D. Used by permission.