Table 1

Time of sample collection

Volunteer

Sample collection (months after birth)

1

6, 8, 8

2

4, 6, 7

3

6, 7, 8, 8

4

7, 7, 8, 9

5

9, 10

6

4 samples within 1 month

7

No information

8

2, 4, 10, 12

Kosaka et al. Silence 2010 1:7   doi:10.1186/1758-907X-1-7