Table 2.
Total sleep duration in hours per day in the three cohorts.
| Generation R Study | GUSTO | MAVAN | |
|---|---|---|---|
| 3 Months | |||
| Mean ± SD | 14.6 ± 3.0 | 12.5 ± 3.5 | 14.2 ± 2.5 |
| Range | 6.0–22.0 | 6.0–22.0 | 7.0–21.0 |
| n | 4800 | 537 | 170 |
| % below recommendation (<12 h)a | 15.2 | 41.7 | 12.9 |
| 6 Months | |||
| Mean ± SD | 15.0 ± 2.7 | 12.1 ± 2.5 | 13.2 ± 1.9 |
| Range | 6.0–21.0 | 6.0–21.0 | 7.0–21.0 |
| n | 3691 | 647 | 483 |
| % below recommendation (<12 h)a | 11.3 | 42.0 | 20.3 |
| 24 Months | |||
| Mean ± SD | 13.4 ± 1.1 | 11.3 ± 1.4 | 12.5 ± 1.2 |
| Range | 6.4–19.0 | 6.5–19.0 | 8.0–16.5 |
| n | 5114 | 374 | 425 |
| % below recommendation (<11 h)a | 2.1 | 30.7 | 8.0 |
| 36 Months | |||
| Mean ± SD | 12.6 ± 1.2 | 11.0 ± 1.5 | 11.8 ± 1.2 |
| Range | 8.5–20.0 | 6.5–20.0 | 7.5–15.0 |
| n | 4847 | 170 | 409 |
| % below recommendation (<10 h)a | 0.4 | 10.6 | 4.9 |
Children with unreliable estimates of sleep duration (<6 h of sleep at all ages and maximum sleep duration of 22, 21 and 24 h at the age of three months, six months and 24/36 months) were excluded from the analyses.
SD, standard deviation.
a
Guidelines from the American Academy of Pediatrics (AAP) recommend the following ranges of sleep duration: infants 4–12 months of age: 12–16 h per 24 h (including naps); children 1–2 y of age: 11–14 h per 24 h (including naps); children 3–5 y of age: 10–13 h per 24 h (including naps).