Research Article

Change and Stability in Sibling Resemblance in Obesity Markers: The Portuguese Sibling Study on Growth, Fitness, Lifestyle, and Health

Table 1

Descriptive statistics (means and standard deviations (SD) and frequencies (%)) for all sib types at baseline and follow-up.

Brother-brother (n = 50)zBrother-sister (n = 84)zSister-sister (n = 34)tAll siblings (n = 168)z
BaselineFollow-upBaselineFollow-upBaselineFollow-upBaselineFollow-up
Mean ± SDMean ± SDMean ± SDMean ± SDMean ± SDMean ± SDMean ± SDMean ± SD

Individual characteristics
Chronological age (yr)12.3 ± 1.414.6 ± 1.619.9812.2 ± 1.414.3 ± 1.314.0211.8 ± 1.314.2 ± 1.317.1012.2 ± 1.414.4 ± 1.425.48
Biological maturation (yr)−0.9 ± 1.50.8 ± 1.716.72−0.9 ± 1.20.6 ± 1.213.64-0.8 ± 1.10.8 ± 0.914.51-0.9 ± 1.30.6 ± 1.323.60
Body fat (%)19.4 ± 5.919.4 ± 6.0−0.06ns21.8 ± 6.022.3 ± 5.91.21ns25.1 ± 4.427.8 ± 5.36.1121.8 ± 5.922.5 ± 6.53.14
Body mass index (kg/m2)19.7 ± 3.520.6 ± 3.76.5418.9 ± 2.619.7 ± 2.63.9419.2 ± 3.120.7 ± 3.47.1319.2 ± 3.020.2 ± 3.18.34
Waist circumference (cm)67.3 ± 9.270.2 ± 10.28.1564.4 ± 5.766.1 ± 5.54.5063.1 ± 6.665.8 ± 6.85.4965.0 ± 7.267.3 ± 7.79.51

Behavioral characteristics
Screen time3.4 ± 2.63.6 ± 2.20.63ns3.0 ± 2.22.9 ± 1.9−0.26ns2.8 ± 2.22.4 ± 2.1−1.00ns3.1 ± 2.33.0 ± 2.1−0.22ns
Total physical activity8.2 ± 2.08.5 ± 1.61.09ns7.6 ± 2.28.0 ± 1.41.62ns7.8 ± 1.37.7 ± 1.9−0.30ns7.8 ± 2.08.1 ± 1.61.73ns
Healthy diet44.0 ± 18.342.5 ± 18.7−0.48ns42.1 ± 5.239.6 ± 13.5−1.47ns41.0 ± 13.938.4 ± 20.4−1.02ns42.5 ± 15.940.2 ± 16.7−1.62ns
Unhealthy diet29.1 ± 19.324.4 ± 15.5−2.0822.6 ± 14.121.2 ± 14.2−1.13ns15.0 ± 7.413.5 ± 7.5−1.34ns23.0 ± 15.620.6 ± 14.023.03

Familial characteristics
Father occupation6.0 ± 2.76.0 ± 2.7−0.00ns5.6 ± 2.55.6 ± 2.51.01ns6.0 ± 2.06.1 ± 2.11.79ns5.8 ± 2.55.9 ± 2.51.98ns
Mother occupation6.7 ± 2.27.1 ± 2.10.86ns5.6 ± 2.75.6 ± 2.7−1.75ns6.2 ± 2.86.2 ± 2.80.00ns6.2 ± 2.66.2 ± 2.60.27ns
Parental support for PA11.8 ± 8.111.3 ± 7.3−0.42ns10.5 ± 6.511.9 ± 6.02.0011.2 ± 6.112.7 ± 5.91.72ns11.0 ± 6.911.9 ± 6.41.77ns

; ; ; ns = nonsignificant.