Table 2.
Infant background characteristics and the initiation and length of diary data collection in the final study group as a whole and the lowest and highest means/medians of the units.
| Infant characteristics | n = 660 | Range of the unit means/medians |
|---|---|---|
| Gestational age (weeks) median (Q1–Q3) | 31.9 (29.0–33.7) | 27.3–33.1 |
| Weight at birth (g) mean (SD) | 1,602 (576) | 1,053–1,936 |
| Gender n (%) | ||
| Female | 286 (43.3) | |
| Male | 374 (56.7) | |
| Delivery n (%) | ||
| C-section | 375 (56.8) | |
| Vaginal | 285 (43.2) | |
| Twins n (%) | ||
| Singleton | 470 (71.2) | |
| Twins | 190 (28.8) | |
| Age at the initiation of diary data collection (days) mean (SD) | 4.28 (5.21) | 1.5–18.8 |
| Number of diary days per infant mean (SD) | 11.6 (3.62) | 9.0–13.3 |
| Length of hospital stay (days) median (Q1–Q3) n = 658 | 23 (13–41) | 15–48 |