Table 1.
Data Sources, Descriptions and Definitions by Country
| Australia | Finland | Norway | Sweden | |
|---|---|---|---|---|
| General population | ||||
| Data source | National Drug Strategy Household Survey | Health Behavior and Health among the Finnish Adult Population Survey | Holiday and Travel Survey | National Public Health Survey |
| Main mode of data collection | Drop-and-collect questionnaire/ telephone interview | Postal questionnaire | Telephone interviews | Postal questionnaire |
| Start and frequency | Every 2–3 y since 1985 | Annual since 1978 | Quarterly since 1973 | Annual since 2004 |
| Data sets in this study | 2001, 2004, 2007, 2010, 2013 | 1995–2014 | 1995–2014 | 2004–2015 |
| Population | Women aged 16–44 | Women aged 15–44 | Women aged 16–44 | Women aged 16–44 |
| Sample | N = 5761–8130 | Subset of total N = 2545–3644 | N = 1079–1576 | N = 1340–2837 |
| Age groups reported | 16–29 y | 15–24 y | 16–24 y | 16–29 y |
| 30–44 y | 25–44 y | 35–44 y | 30–44 y | |
| Definition of smoker | Daily smoking | Daily smoking | Daily smoking | Daily smoking |
| Pregnant women | ||||
| Data source | National Drug Strategy Household Survey | Medical Birth Registry | Medical Birth Registry | Medical Birth Registry |
| Main mode of data collection | Drop-and-collect questionnaire/ telephone interview | Medical records | Medical records | Medical records |
| Start and frequency | Every 2–3 y since 1985 | Annual data since 1987 | Annual data since 1973 | Annual data since 1973 |
| Data sets in this study | 2001, 2004, 2007, 2010, 2013 | 1995–2014 | 1999–2014a | 2000–2014a |
| Population | Women who were pregnant at time of survey | All children with birth weight >500 grams after week 22 | All births after week 12 | All births |
| Sample | N = 898, 888, 652, 817, 873 | Whole population | Whole population | Whole population |
| Age groups reported | 16–29 y | <20 y | <20 y | <20 y |
| 30–44 y | 0–24 y | 20–24 y | 20–24 y | |
| 25–29 y | 25–29 y | 25–29 y | ||
| 30–39 y | 30–34 y | 30–39 y | ||
| 35–39 y | ||||
| Definition of smoker | Reported any smoking after knowledge of pregnancy | Continued smoking after first trimester | Smoking “at the end of the pregnancy”b | Smoking in week 30–32 of pregnancy |
aMaternal smoking habits recorded since 1999.
bSmoking habits are only recorded if the mother consents. Data was available for 80%–88% of the pregnancies.