Table 1

Demographic and anthropometric characteristics of children aged 8–17 years old from 1997 to 2016

Trying to lose weightNot trying to lose weight
nMean±SD/%nMean±SD/%
Age (years)866112.4±2.4725 57411.5±2.52*
Age group
8–12533060.518 37170.7*
13–17333139.5720329.3*
Weight (kg)866153.0±22.025 57440.8±16.8*
BMI z-score64462.56±1.4723 6041.03±1.62*
BMI category
Thinness60.14822.2*
Normal102317.411 80451.5*
Overweight123119.7471419.8
Obesity420662.8660426.6*
Gender
Boys344040.413 62853.9*
Girls522159.611 94646.1*
Ethnicity
White705379.122 07484.8*
Asian81010.916587.5*
Black3945.28063.5*
Other and mixed4044.910364.3
Household income level
Q1187527.5495424.1*
Q2158621.5444220.2
Q3155720.9467720.9
Q4131317.1437519.1*
Q598813.1354015.6*
  • Estimates are mean±SD or % in which % are added up vertically; BAZ, BMI for age z-score; Q1 (<=GBP11 676.65), Q2 (>GBP11 676.65<=GBP19 117.65), Q3 (>GBP19 117.65<=GBP27 704.92), Q4 (>GBP27 704.92<=GBP47 794.12) and Q5 (>GBP47 794.12). Children ‘Not-trying to lose weight’ include those ‘trying to gain weight (n=1,456 (4.2%))’. Missing values; BAZ classfications 16.8%, household income level 15.6%.

  • *Significant different (p<0.05) between groups (χ2 and t-test).

  • BAZ, body mass index for age z-score ; BMI, body mass index .