Table 5.

Average yearly change in rates of neural tube defects, after and up to local recommendations

		Incidence rate ratio*(95% CI)
Area	Period	Total neural tube defects	Spina bifida	Anencephaly
Norway	1994-8	0.93 (0.85 to 1.02)	0.97 (0.86 to 1.08)	0.88 (0.76 to 1.02)
	1988-93	0.98 (0.91 to 1.05)	0.96 (0.88 to 1.05)	1.02 (0.90 to 1.15)
Finland	1996-8	1.18 (0.97 to 1.44)	1.24 (0.96 to 1.60)	1.11 (0.82 to 1.51)
	1988-95	0.99 (0.95 to 1.04)	1.03 (0.97 to 1.09)	0.95 (0.89 to 1.02)
Northern Netherlands	1994-8	0.96 (0.82 to 1.13)	0.94 (0.77 to 1.15)	0.99 (0.76 to 1.29)
	1988-93	0.88 (0.79 to 0.98)	0.89 (0.78 to 1.01)	0.85 (0.68 to 1.07)
England and Wales	1993-8	0.97 (0.95 to 0.99)	0.97 (0.94 to 1.00)	0.97 (0.94 to 1.01)
	1988-92	0.96 (0.93 to 0.99)	0.96 (0.92 to 0.99)	0.96 (0.92 to 1.00)
Ireland, Dublin	1994-8	0.91 (0.78 to 1.06)	0.88 (0.72 to 1.07)	0.97 (0.75 to 1.24)
	1988-93	0.90 (0.82 to 0.99)	0.92 (0.81 to 1.05)	0.88 (0.77 to 1.01)
France, Strasbourg	1996-7	0.44 (0.19 to 1.02)	0.36 (0.12 to 1.14)	0.57 (0.17 to 1.94)
	1988-95	1.04 (0.94 to 1.13)	1.03 (0.89 to 1.19)	1.04 (0.92 to 1.17)
France, Paris	1996-8	0.96 (0.76 to 1.21)	0.78 (0.57 to 1.08)	1.21 (0.87 to 1.70)
	1988-95	1.03 (0.98 to 1.08)	1.04 (0.97 to 1.12)	1.01 (0.95 to 1.09)
France, Central East	1996-8	0.96 (0.80 to 1.14)	0.99 (0.80 to 1.23)	0.87 (0.62 to 1.22)
	1988-95	1.05 (1.01 to 1.09)	1.06 (1.01 to 1.11)	1.04 (0.98 to 1.11)
Hungary	1997-8	1.24 (0.72 to 2.14)	1.25 (0.68 to 2.29)	1.24 (0.38 to 4.05)
	1988-96	0.85 (0.81 to 0.88)	0.83 (0.80 to 0.87)	0.92 (0.83 to 1.01)

^*Estimates the average yearly change in rate (<1 indicates decreasing rates; >1 indicates increasing rates.