Two physicians were asked to classify 100 chest x-rays as abnormal or normal independently. The comparison of their classification is shown in the following table:

Physician 2 Total

Physician 1 Abnormal Normal

Abnormal 40 20 = 60

Normal 10 30 =40

Total 50 50 =100

a.Calculate the overall percent agreement between the two physicians.

b.Would you characterize the value of kappa as poor, good or excellent?