CT measurement

Correlation coefficient (r) for spirometric value

FEV₁

FEV₁

(% predicted)

FEV₁/FVC

FEF_25-75%

FEF_25-75%

(% predicted)

Peak flow

Mean tracheal CSA

0.469

(P < 0.05)

0.312

(NS)

0.044

(NS)

0.266

(NS)

0.176

(NS)

0.410

(P < 0.05)

Minimum tracheal CSA

0.435

(P < 0.05)

0.289

(NS)

0.333

(NS)

0.259

(NS)

0.228

(NS)

0.578

(P < 0.01)

LAA%

−0.195

(NS)

−0.319

(NS)

−0.196

(NS)

−0.306

(NS)

−0.350

(NS)

−0.119

(NS)