Table 1.

Subgroup analysis of the sensitivity, specificity and likelihood ratios of the Papanicolaou smear test

			Clinical reading (n = 1781)				Optimized interpretation (n = 1777)
Variables†	n (%)	Disease prevalence n (%)	Sensitivity %	Specificity %	Positive likelihood ratio	Negative likelihood ratio	Sensitivity %	Specificity %	Positive likelihood ratio	Negative likelihood ratio
HPV test
Positive	537 (30)	282 (53)	95	76	4.02	0.07	92	76	3.93	0.10
Negative	1244 (70)	73 (6)	64	93	9.31	0.38	64	93	8.85	0.38
Study setting
Screening	1320 (74)	70 (5)	70	94	12.32	0.32	75	92	8.96	0.27
Referral clinic	461 (26)	285 (62)	93	60	2.34	0.12	89	77	3.90	0.14
Age
<35 years	981 (55)	158 (16)	89	92	11.66	0.12	83	91	9.44	0.19
≥ 35 years	800 (45)	197 (25)	88	87	6.79	0.14	89	88	7.37	0.12
Current smoking
Yes	602 (34)	161 (27)	90	88	7.22	0.11	87	89	7.67	0.15
No	1161 (66)	188 (16)	87	91	9.98	0.14	87	90	8.94	0.15
European origin
Yes	1623 (91)	312 (19)	88	91	9.71	0.13	87	90	8.81	0.15
No	158 (9)	43 (27)	91	81	4.74	0.11	83	86	5.99	0.19
Educational level
< Higher	1063 (60)	227 (21)	88	87	7.15	0.14	87	88	7.31	0.15
≥ Higher	709 (40)	128 (18)	89	93	14.38	0.12	86	92	11.06	0.15
Postmenopausal
Yes	174 (10)	44 (25)	86	88	7.49	0.15	93	91	10.09	0.08
No	1607 (90)	311 (19)	89	90	9.13	0.12	85	90	8.31	0.16
Contraception
None	640 (36)	127 (20)	89	89	8.30	0.12	87	90	8.93	0.14
Combined oral pill	905 (51)	173 (19)	87	91	9.26	0.14	83	90	8.50	0.19
Others	236 (13)	55 (23)	91	91	9.68	0.10	96	87	7.27	0.04

† Data were missing for the following variables: current smoking (18 patients) and educational level (9 patients).

Significant comparisons are indicated in bold.