Chlamydia and gonorrhoea in pregnant Batswana women: time to discard the syndromic approach?

BMC Infectious Diseases

Table 4 Diagnostic strategies to identify infection with Chlamydia trachomatis and/or Neisseria gonorrhoeae in 703 antenatal care attendees in Botswana.

	Positive on assessment		Cervical infection		Sensitivity	Specificity	LR+*	LR-	PPV	NPV
	n	(%)	N	(%)
Symptoms and signs
VDS algorithm	104	(15)	11	(11)	0.16	0.85	1.12 (0.63–1.92)	0.98	0.11	0.91
Symptoms alone: VD and/or LAP	155	(22)	14	(9)	0.21	0.78	0.94 (0.57–1.49)	1.02	0.09	0.90
Signs alone: VD (excl. candidiasis)	227	(32)	30	(13)	0.45	0.69	1.45 (1.06–1.89)	0.78	0.13	0.92
Risk scores†, sensitivity minimum 0.7
Sociodemographic risk score	327	(47)	50	(15)	0.75	0.56	1.71 (1.42–1.99)	0.45	0.15	0.96
Clinical risk score	372	(53)	54	(15)	0.81	0.50	1.61 (1.37–1.83)	0.39	0.15	0.96
Microscopy risk score	273	(39)	51	(19)	0.76	0.65	2.18 (1.80–2.55)	0.37	0.19	0.96
Risk scores, sensitivity minimum 0.4
Sociodemographic risk score	156	(22)	29	(19)	0.43	0.80	2.17 (1.55–2.91)	0.71	0.19	0.93
Clinical risk score	117	(17)	29	(25)	0.43	0.86	3.13 (2.20–4.30)	0.66	0.25	0.94
Microscopy risk score	116	(17)	29	(25)	0.43	0.86	3.16 (2.22–4.34)	0.66	0.25	0.94

LR+ = positive likelihood ratio; LR- = negative likelihood ratio; PPV = positive predictive value; NPV = negative predictive value; VDS = vaginal discharge syndrome;
LAP = lower abdominal pain; VD = vaginal discharge
* The positive likelihood ratios are calculated with 95% confidence interval.
†Risk factors included in each risk score are described in Table 1

ISSN: 1471-2334