Table 2.

Relationship between categories of missingness on an intimate partner violence screen item and socio-demographic, pregnancy-related, and birth outcome covariates

Covariate	Missing item on FF form vs. screened for IPV1 (AOR (99% CI))	Missing FF form vs. screened for IPV1 (AOR (99% CI))	Missing FF form vs. missing item on FF form2 (AOR (99% CI))
Socio-demographic covariates
Maternal age at birth
Less than 20 years	1.00	1.00	1.00
20 to 24 years	0.92 (0.80, 1.06)	0.60 (0.52, 0.70)**	0.67 (0.56, 0.80)**
25 to 29 years	0.92 (0.80, 1.05)	0.53 (0.46, 0.62)**	0.61 (0.51, 0.73)**
30 to 34 years	0.88 (0.76, 1.01)	0.47 (0.40, 0.55)**	0.56 (0.46, 0.67)**
35 to 39 years	0.85 (0.72, 0.99)*	0.48 (0.40, 0.58)**	0.58 (0.47, 0.73)**
40 years and older	0.99 (0.79, 1.26)	0.51 (0.37, 0.71)**	0.51 (0.36, 0.73)**
Marital status
Married/common-law	1.00	1.00	1.00
No registered union	1.15 (1.07, 1.22)**	1.35 (1.24, 1.48)**	1.11 (1.001, 1.23)*
Area-level income quintile
1 (lowest)	0.88 (0.80, 0.98)*	1.48 (1.28, 1.71)**	1.56 (1.33, 1.84)**
2	0.84 (0.76, 0.94)**	1.29 (1.12, 1.49)**	1.39 (1.18, 1.64)**
3	0.84 (0.76, 0.93)**	1.23 (1.07, 1.42)**	1.41 (1.19, 1.67)**
4	0.95 (0.86, 1.05)	1.19 (1.03, 1.37)*	1.23 (1.04, 1.45)*
5 (highest)	1.00	1.00	1.00
Total children in home
0	2.14 (1.33, 3.43)**	5.73 (3.91, 8.63)**	2.74 (1.73, 4.33)**
1	1.00	1.00	1.00
2	1.14 (1.06, 1.22)**	1.11 (1.01, 1.23)*	0.98 (0.87, 1.09)
3 or more	1.29 (1.19, 1.41)**	1.44 (1.29, 1.60)**	1.08 (0.95, 1.22)
Health region of residence
Winnipeg	1.00	1.00	1.00
Southern Health	0.13 (0.11, 0.14)**	0.39 (0.34, 0.45)**	2.77 (2.32, 3.31)**
Interlake-Eastern	0.22 (0.19, 0.26)**	0.78 (0.66, 0.92)**	3.11 (2.53, 3.83)**
Prairie Mountain	0.19 (0.16, 0.21)**	0.54 (0.47, 0.61)**	2.78 (2.34, 3.31)**
Northern	0.12 (0.09, 0.16)**	1.70 (1.44, 2.00)**	13.10 (9.79, 17.54)**
Low maternal education
No	1.00	NA	NA
Yes	1.12 (1.002, 1.24)*	NA	NA
Social assistance receipt/financial difficulties
No	1.00	NA	NA
Yes	1.56 (1.41, 1.74)**	NA	NA
Pregnancy-related covariates
Low number of prenatal care visits
No	1.00	1.00	1.00
Yes	1.34 (1.19, 1.52)**	1.61 (1.41, 1.84)**	1.22 (1.04, 1.43)*
Parity
Primaparous	1.00	1.00	1.00
Multiparous	1.28 (1.10, 1.48)**	1.48 (1.24, 1.76)**	1.18 (0.97, 1.43)
Maternal prenatal mood or anxiety
No	1.00	1.00	1.00
Yes	1.04 (0.95, 1.14)	1.07 (0.96, 1.21)	1.03 (0.90, 1.18)
Maternal smoking during pregnancy
No	1.00	NA	NA
Yes	1.42 (1.30, 1.55)**	NA	NA
Maternal alcohol use during pregnancy
No	1.00	NA	NA
Yes	1.16 (1.04, 1.29)**	NA	NA
Maternal drug use during pregnancy
No	1.00	NA	NA
Yes	1.68 (1.42, 1.98)**	NA	NA
Birth outcomes
Child sex
Male	1.00	1.00	1.00
Female	1.00 (0.94, 1.06)	0.99 (0.91, 1.07)	1.00 (0.91, 1.10)
Preterm birth
No	1.00	1.00	1.00
Yes	1.21 (1.06, 1.37)**	1.46 (1.25, 1.70)**	1.13 (0.95, 1.35)
Low birthweight
No	1.00	1.00	1.00
Yes	1.19 (1.02, 1.38)*	1.52 (1.27, 1.83)**	1.27 (1.03, 1.57)*
High birthweight
No	1.00	1.00	1.00
Yes	1.12 (0.93, 1.35)	1.11 (0.88, 1.40)	1.03 (0.78, 1.34)
Small for gestational age
No	1.00	1.00	1.00
Yes	1.05 (0.93, 1.17)	1.01 (0.87, 1.18)	0.97 (0.81, 1.16)
Large for gestational age
No	1.00	1.00	1.00
Yes	1.00 (0.91, 1.09)	0.99 (0.88, 1.12)	1.00 (0.87, 1.14)

FF Families First screening form, IPV intimate partner violence, NA variable was not available in data due to missing FF screen form, AOR adjusted odds ratio (i.e., all models in this table are adjusted for maternal age, marital status, total number of children in home, area-level income, and provincial region of residence)

¹Screened for IPV is the reference group for the dependent variable in logistic regression models

²Missing a response to the IPV screen question on the FF form is the reference group for the dependent variable in logistic regression models

*p < 0.01; **p < 0.001