Table II.

Worst diagnosis (histology and cytology in the absence of histology) at follow-up for women with normal cytology at baseline.

	Groups			Crude relative risks (RR (95%CI))			Adjusted relative risks** (aRR (95%CI))
Most severe follow-up diagnosis	HIUD N = 53 283	CIUD N = 27 222	OC N = 146 818	HIUD versus OC	CIUD versus OC	HIUD versus CIUD	HIUD versus OC	CIUD versus OC	HIUD versus CIUD
Histology	6193 (11.6)	2298 (8.4)	14 000 (9.5)
CIN3+	645 (1.2%)	373 (1.4%)	3810 (2.6%)	0.47 (0.43–0.51)	0.53 (0.47–0.58)	0.88 (0.77–1.00)	0.63 (0.57–0.69)	0.58 (0.52–0.65)	1.08 (0.94–1.22)
CIN2	413 (0.8%)	197 (0.7%)	1629 (1.1%)	0.70 (0.62–0.77)	0.65 (0.56–0.75)	1.07 (0.89–1.25)	0.86 (0.75–0.96)	0.68 (0.57–0.78)	1.27 (1.05–1.48)
CIN1	641 (1.2%)	296 (1.1%)	1794 (1.2%)	0.98 (0.90–1.07)	0.89 (0.78–1.00)	1.11 (0.95–1.26)	1.15 (1.03–1.27)	0.95 (0.83–1.07)	1.21 (1.05–1.38)
Normal histology	4408 (8.3%)	1395 (5.1%)	6466 (4.4%)	1.88 (1.81–1.95)	1.16 (1.10–1.23)	1.61 (1.52–1.71)	1.67 (1.60–1.74)	1.14 (1.07–1.21)	1.46 (1.38–1.55)
Undefined* hist	86 (0.2%)	37 (0.1%)	301 (0.2%)	0.79 (0.60–0.98)	0.66 (0.44–0.89)	1.19 (0.73–1.64)	0.69 (0.51–0.87)	0.63 (0.41–0.85)	1.09 (0.67–1.52)
Cytology	47 090 (88.4)	24 924 (91.6)	132 818 (90.4)
ASCUS+	1189 (2.2%)	673 (2.5%)	4356 (3.0%)	0.75 (0.70–0.80)	0.83 (0.77–0.90)	0.90 (0.82–0.99)	0.77 (0.72–0.83)	0.85 (0.78–0.93)	0.90 (0.82–0.99)
Normal cytology	45 108 (84.7%)	24 130 (88.6%)	127 793 (87.0%)	0.97 (0.97–0.98)	1.02 (1.01–1.02)	0.96 (0.95–0.96)	0.97 (0.97–0.98)	1.02 (1.01–1.02)	0.95 (0.95–0.96)
Undefined* cyt	793 (1.5%)	121 (0.4%)	669 (0.5%)	3.27 (2.93–3.60)	0.98 (0.79–1.16)	3.35 (2.71–3.99)	3.04 (2.69–3.40)	1.11 (0.89–1.34)	2.74 (2.21–3.26)

Data are crude and adjusted RR with 95% CI. N, number.

^*Other/unsatisfactory.

^**Adjusted for age, region of residence, education level before age 32 years, time to follow-up, and duration of IUD or OC use.