Table 3.
Results from logistic regression analysis for preconceptional folic acid knowledge and preconceptional intention to seek for care with “yes, she certainly should” as reference category
| Preconceptional folic acid knowlegdea | Preconceptional intention to seek for careb | ||||
|---|---|---|---|---|---|
| Ic | IIc | IIIc | Ic | IIc | |
| Study years | |||||
| 2007 | 0.74 (0.63–0.87)** | 0.73 (0.61–0.88)** | 0.73 (0.61–0.88)** | 0.53 (0.40–0.69)** | 0.51 (0.39–0.68)** |
| 2009 | 0.97 (0.82–1.14) | 1.00 (0.83–1.19) | 0.99 (0.83–1.19) | 0.61 (0.47–0.81)** | 0.61 (0.46–0.81)** |
| 2010 | reference | reference | reference | 0.58 (0.44–0.77)** | 0.61 (0.46–0.81)** |
| 2011 | NA | NA | NA | 1.14 (0.86–1.51) | 1.19 (0.89–1.59) |
| 2012 | NA | NA | NA | 1.42 (1.07–1.90)* | 1.54 (1.14–2.07)* |
| 2013 | NA | NA | NA | 1.00 (0.75–1.34) | 1.01 (0.75–1.37) |
| 2014 | NA | NA | NA | reference | reference |
| Socio-demographics | |||||
| Gender (reference: women) | |||||
| Men | 0.42 (0.36–0.49)** | 0.42 (0.36–0.49)** | 1.41 (1.22–1.64)** | ||
| Age in years (reference: 25–44) | |||||
| 16–24 | 0.31 (0.24–0.40)** | 0.30 (0.23–0.39)** | 1.38 (1.07–1.79)* | ||
| 45 and older | 0.40 (0.34–0.48)** | 0.40 (0.33–0.47)** | 1.09 (0.91–1.30) | ||
| Ethnicity (reference: Dutch) | |||||
| Non-Western immigrants | 0.57 (0.46–0.71)** | 0.45 (0.33–0.62)** | 1.94 (1.59–2.35)** | ||
| Western immigrants | 0.69 (0.53–0.91)* | 0.74 (0.44–1.26) | 1.59 (1.23–2.05)** | ||
| Socio-economic status | |||||
| Educational level (scale) | 1.31 (1.10–1.55)* | 1.20 (0.98–1.47) | 1.13 (0.94–1.35) | ||
| Household income (reference: >2× moderate) | |||||
| Minimum | 0.59 (0.46–0.77)** | 0.60 (0.46–0.77)** | 1.56 (1.22–2.01)** | ||
| Minimum-moderate | 0.66 (0.53–0.83)** | 0.66 (0.52–0.82)** | 1.60 (1.26–2.02)** | ||
| Moderate-2× moderate | 0.79 (0.65–0.96)* | 0.78 (0.64–0.95)* | 1.07 (0.87–1.31) | ||
| Employment status (reference: employed) | |||||
| Unemployed | 0.93 (0.78–1.10) | 0.92 (0.78–1.10) | 1.18 (1.00–1.40) | ||
| Neighbourhood (reference: deprived) | |||||
| Non-deprived | 0.97 (0.83–1.15) | ||||
| Other variables | |||||
| Children living in the household (reference: yes) | |||||
| No | 0.60 (0.51–0.71)** | 0.60 (0.51–0.70)** | 1.60 (1.36–1.88)** | ||
| Religion (reference: yes) | |||||
| No | 1.03 (0.88–1.21) | 1.03 (0.87–1.20) | NA | ||
| Interaction | |||||
| Ethnicity*educational level (ref: Dutch* educational level) | |||||
| Non-Western* educational level | 1.46 (1.01–2.11)* | ||||
| Western* educational level | 0.92 (0.50–1.70) | ||||
aPreconceptional folic acid knowledge among respondents answering ‘other’ vs. ‘yes’ on: “A woman who wishes to become pregnant should take folic acid supplementation before she tries to become pregnant”. N = 3766; Rotterdam, the Netherlands, 2007, 2009 and 2010
bPreconceptional intention to consult a GP or midwife among respondents answering ‘no’ vs. ‘yes’ on: “A woman who wishes to become pregnant should consult a GP or midwife before she tries to become pregnant”. N = 2771; Rotterdam, the Netherlands, 2007, 2009–2014
cIn model I the study years were entered, in model II socio-demographics, socio-economic status and other variables were included, and in model III the observed interaction between ethnicity and educational level was included
Data are in OR, odds ratio (95 % confidence interval). OR = exp (ß), where ß is the coefficient in the logistic model
* p ≤0.05; ** p ≤0.001
NA Not Accounted
Nagelkerke for preconceptional folic acid knowledge: step I R2 = 0.006, step II R2 = 0.181, step III R2 = 0.181 and for preconceptional intention to seek for care: step I R2 = 0.042, step II R2 = 0