Table 1.
Availability of Data on Exposure and Outcomes and the Study Population for 4 Cohorts Included in an Analysis of Maternal Cell-Phone Use During Pregnancy and Birth Outcomes, 1996–2011
| Study Cohort | Location of Cohort | Enrollment | Cell-Phone Use During Pregnancy | Pregnancy Duration and Fetal Growth Outcomes | Study Population | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| Time Period | No. of Pairsa Enrolled (n = 113,319) | Time of Data Collection | No. of Pairs (n = 56,079) | % of Those Enrolled (49.5%) | No. of Pairs (n = 65,637) | % of Those Enrolled (57.9%) | No. of of Pairs Included in Analysis (n = 55,507) | % of Those Enrolled (49.0%) | ||
| DNBC | Denmark | 1996–2002 | 101,032 | 7 years postnatal | 50,040 | 49.5 | 54,498b | 53.9 | 49,668 | 49.2 |
| ABCD | The Netherlands | 2003–2004 | 8,266 | 7 years postnatal | 2,611 | 31.6 | 7,812 | 94.5 | 2,597 | 31.4 |
| INMA | Spain | 2003–2008 | 2,270 | Pregnancy | 1,993 | 87.8 | 1,975 | 87.0 | 1,934 | 85.2 |
| MOCEH | South Korea | 2006–2011 | 1,751 | Pregnancy | 1,435 | 82.0 | 1,352c | 77.2 | 1,308 | 74.7 |
Abbreviations: ABCD, Amsterdam Born Children and Their Development Study; DNBC, Danish National Birth Cohort; INMA, Spanish Environment and Childhood Project; MOCEH, Korean Mothers and Children’s Environment Health Study.
a Number of mother-child pairs.
b Out of 54,908 offspring whose mothers responded to the age 7 years questionnaire.
c Out of 1,481 offspring whose mothers responded to the cell-phone use questionnaire.