Table 3 The sensitivity and specificity of self-taken and nurse-taken swabs for the detection of CT and GC

	Method of collection	Sensitivity (95% CI)		p Value (no of true positives)	Specificity (95% CI)	p Value (no of true negatives)
Rectal GC* (n = 262)	Nurse	94.9% (82.7 to 99.4)	1.00 (39)		90.1% (85.4 to 93.7)	0.30 (223)
Rectal GC* (n = 262)	Patient	92.3% (79.1 to 98.4)	1.00 (39)		87.9% (82.9 to 91.9)	0.30 (223)
Pharyngeal GC* (n = 262)	Nurse	88.2% (63.6 to 98.5)	0.50 (17)		91.8% (87.7 to 94.9)	0.006 (245)
Pharyngeal GC* (n = 262)	Patient	100% (80.5 to 100)	0.50 (17)		87.8% (83.0 to 91.6)	0.006 (245)
Rectal CT† (n = 258)	Nurse	80.0% (63.1 to 91.6)	0.13 (35)		99.6% (97.5 to 100)	0.25 (223)
Rectal CT† (n = 258)	Patient	91.4% (76.9 to 98.2)	0.13 (35)		98.2% (95.5 to 99.5)	0.25 (223)

*Nurse and patient-taken swabs (tested by AC2) compared with GC culture results.
†Nurse and patient taken swabs (tested by AC2) compared with clinic strand displacement assay (SDA) result.
CT, C trachomatis; GC, N gonorrhoeae.