Table 2. Inter-reader reliability for the major features reported on the Chest Radiograph Reading and Recording System.

Feature	% agreement	kappa (standard error)
Large opacity (>1 cm)	85.7	0.7 (0.6,0.8)
Small opacity (<1 cm)	92.6	0.56 (0.46,0.66)
Cavity	91.1	0.64 (0.54, 0.74)
Effusion	88.6	0.77 (0.59,0.95)
“Consistent with active TB”*	86.1	0.52 (0.42,0.62)

^*This judgment (consistent or not consistent with active TB) was the interpretation of the reader recorded on completion of the CRRS read in the appropriate block on the CRRS form. (see online repository).