Table 4.

Univariate and multivariate analyses for factors related to fertility knowledge in the Triers group

	Univariate association (n = 618)		Multivariate linear regression (n = 521, R-squared for model = 0.13)
Variables	Mean (SD)	P	Coefficient a	95% confidence interval	P
Socio-demographic
Gender
Male	49.9 (23.8)		Reference
Female	56.3 (22.7)	<0.001	3.28	-0.86 to 7.41	0.12
Age
each additional year older	-0.01b	0.72	-0.22	-0.52 to 0.08	0.16
Annual household income
< 4 million JPY	50.9 (24.1)		Reference
4 - 7 million JPY	53.0 (23.8)		1.56	-2.95 to 6.07	0.50
≥ 8 million JPY	53.0 (23.5)	0.62	1.03	-5.24 to 7.30	0.75
Educational level
No university education	53.5 (23.5)		Reference
University education	52.7 (23.3)	0.69	-0.94	-5.39 to 3.51	0.68
Fertility
Whether or not given birth
Not given birth/fathered a child	54.6 (23.6)		Reference
Given birth/fathered a child	50.8 (23.0)	0.046	-3.38	-7.42 to 0.67	0.10
How long trying to conceive
Trying to conceive < 12 months	50.5 (23.2)		Reference
Trying to conceive ≥ 12 months	54.2 (23.5)	0.08	0.15	-4.71 to 5.02	0.95
Prior medical consultation
Not consulted a medical doctor	48.6 (23.2)		Reference
Consulted a medical doctor	61.6 (21.5)	<0.001	11.64	7.28 to 16.0	<0.001
Health-related skills and behaviour
Smoking status
Non-smoking	54.3 (22.8)		Reference
Smoking	48.7 (25.3)	0.02	-1.89	-7.24 to 3.46	0.49
The score of HLS-14
Each additional score higher	0.22c	<0.001	0.59	0.30 to 0.88	<0.001
The score of the Lipkus-J
Each additional score higher	0.072c	0.08	0.27	-0.80 to 1.35	0.62

Note: With regards to annual household incomes, 97 people who answered “unknown” were excluded from the analysis.

^aNon-standardized coefficient. ^bPearson’s correlation coefficient.

^cSpearman’s correlation coefficient.