Table 1. Study group characteristics by age and feeding regimen.
Differences in group means were tested with ANOVA and for distributions in groups by chi-square test for the 4- and 12-month olds, respectively.
| 4 months old | 12 months old | |||||||
|---|---|---|---|---|---|---|---|---|
| EF | SF | BFR | p-value groups | EF | SF | BFR (at 4 month) | p-value groups | |
| Numbers in basic studya | 76 | 73 | 73 | − | 73 | 68 | 72 | − |
| Numbers with sequencingb | 46 | 41 | 37 | − | 59 | 55 | 52 | − |
| Boysb (%) | 52 | 56 | 40 | 0.387 | 49 | 49 | 48 | 0.993 |
| Lengthb (cm) | 64 (64–65) | 64 (63–65) | 64 (63–65) | 0.555 | 76.5 (75.8–77.1) | 76.0 (75.4–76.7) | 75.5 (74.9–76.1) | 0.108 |
| Length gain 0–12 mob, cm | − | − | − | − | 26.2 (25.5–26.9) | 25.3 (24.8–25.9) | 24.6 (24.0–25.2) | 0.002 |
| Weightb (kg) | 6.9 (6.7–6.9) | 6.9 (6.6–7.2) | 6.7 (6.5–6.9) | 0.450 | 10.2 (9.8–10.5) | 10.1 (9.8–10.4) | 9.9 (9.6–10.1) | 0.131 |
| Weight gain 0–12 mo, kg | − | − | − | − | 6.7 (6.4–7.0) | 6.6 (6.2–6.9) | 6.2 (5.9–6.5) | 0.062 |
| Caesarean section (%) | 18.8 | 17.5 | 7.5 | 0.087 | − | − | − | − |
| Probiotic dropsc (%) | 6.5 | 2.4 | 13.5 | 0.165 | 0 | 0 | 0 | − |
| Antibioticsd (%) | 0 | 0 | 0 | − | 13.3d | 10.2d | 6.7d | 0.627 |
| Total number of quality filtered sequences (mean) | 54 459 | 59 600 | 58 613 | 0.322 | 51 896 | 48 858 | 47 108 | 0.336 |
a) Remaining infants out of 80 included 0–2 mo old infants at study start. Those who left between recruitment and study start did this for time constraints.
b) The numbers refers to infants with oral swabs analyzed for Illumina MiSeq sequencing of the v3-v4 hypervariable regions of 16S rDNA. The lower numbers at 4 month, compared to numbers included in the basic study, is due to that the basic study was running when inclusion to the present study began. The lower numbers at 12 mo is due to that the child did not cooperate for swabbing.
c) These children (5, 1, 3 infants, respectively) reported having taken probiotic drops (L. reuteri) during the last several months. No significant difference was seen in phyla, genera or species prevalences between those who reported intake and those who reported no intake.
d) These children (3, 5, 6 infants, respectively) had taken antibiotics once between 7–12 mo of age but with no closer specification when it was taken. No significant difference was seen in phyla, genera or species prevalences between those who reported intake and those who reported no intake.