Table 1.
Participants’ neonatal and socio-demographic details
| Assessed at 15 years | Assessed 19 at years | Assessed at both time points | |||||
|---|---|---|---|---|---|---|---|
| VLBW | Control | VLBW | Control | VLBW | Control | ||
| Number of participants | 40 | 56 | 44 | 60 | 30 | 37 | |
| Males (%) | 18 (45) | 21 (37) | 18 (41) | 25 (42) | 11 (37) | 14 (38) | |
| Background information | |||||||
| Birthweight (grams) M (SD) | 1204 (236)*** | 3713 (500) | 1212 (234)*** | 3698 (501) | 1223 (250)*** | 3766 (544) | |
| Gestational age (weeks) M (SD) | 29.18 (2.65)*** | 39.61 (1.15) | 29.25 (2.54)*** | 39.72 (1.27) | 29.43 (2.60)*** | 39.51 (1.17) | |
| Age (years-months) M (SD) | 15-2 (0-6) | 15-5 (0-5) | 19-7 (0-7) | 19-8 (0-6) | Time 1 | 15-2 (0-6) | 15-5 (0-5) |
| Time 2 | 19-9 (0-8) | 19-7 (0-6) | |||||
| IQ M (SD) | 89.00 (12.54)*** | 99.85 (10.62) | 86.33 (13.52)*** | 100.14 (11.03) | |||
| SES (1 – 5) M (SD) | 3.15 (1.25) | 3.59 (1.04) | 3.39 (1.38) | 3.70 (0.95) | 3.27 (1.33) | 3.65 (0.92) | |
| SES class 1 n (%) | 5 (12) ** | 0 (0) | 6 (15) * | 1 (2) | 4 (13) * | 0 (0) | |
| SES class 2 n (%) | 7 (17) | 10 (18) | 5 (12) | 4 (7) | 5 (17) | 4 (11) | |
| SES class 3 n (%) | 11 (28) | 16 (29) | 7 (17) | 17 (32) | 6 (20) | 12 (32) | |
| SES class 4 n (%) | 11 (28) | 17 (30) | 13 (32) | 21 (39) | 9 (30) | 14 (38) | |
| SES class 5 n (%) | 6 (15) | 13 (23) | 10 (24) | 11 (20) | 6 (20) | 7 (19) | |
*p ≤ 0.05, **p ≤ 0.01, ***p ≤ 0.001 (VLBW versus controls). Significant results marked bold. Linear regression adjusted for age and sex for normal distributed data, else the Mann–Whitney U-test
The unconditional z-pooled test was used to analyze differences in proportions between groups
Abbreviations: IQ Intelligence quotient, M Mean, SD standard deviation, SES socio-economic status, VLBW very low birth weight (birth weight ≤ 1500)
A version of this table has been previously published by our group [37]. In this new version we have included detailed data regarding SES class results