TABLE 2.
Descriptive characteristics of the IDEFICS/I.Family study sample for the longitudinal analysis; pooled sample and stratified by sex
| Pooled |
Boys |
Girls |
||||
|---|---|---|---|---|---|---|
| n | % | n | % | n | % | |
| Sex | ||||||
| Boys | 410 | 50 | 410 | 100 | 0 | 0 |
| Girls | 402 | 50 | 0 | 0 | 402 | 100 |
| Iron deficiency1 | ||||||
| W0: yes | 25 | 3 | 20 | 5 | 5 | 1 |
| W3: yes | 54 | 7 | 22 | 5 | 32 | 8 |
| Mainly vegetarian2 | ||||||
| W0: yes | 9 | 1 | 2 | 0 | 7 | 2 |
| W3: yes | 42 | 5 | 20 | 5 | 22 | 5 |
| Country | ||||||
| Italy | 58 | 7 | 30 | 7 | 28 | 7 |
| Estonia | 169 | 21 | 83 | 20 | 86 | 21 |
| Cyprus | 4 | 0 | 2 | 0 | 2 | 0 |
| Belgium | 72 | 9 | 31 | 8 | 41 | 10 |
| Sweden | 98 | 12 | 50 | 12 | 48 | 12 |
| Germany | 133 | 16 | 74 | 18 | 59 | 15 |
| Hungary | 131 | 16 | 67 | 16 | 64 | 16 |
| Spain | 147 | 18 | 73 | 18 | 74 | 18 |
| BMI category3 (W3) | ||||||
| Underweight | 60 | 7 | 30 | 7 | 30 | 7 |
| Normal | 574 | 71 | 285 | 70 | 289 | 72 |
| Overweight | 138 | 17 | 72 | 18 | 66 | 16 |
| Obese | 40 | 5 | 23 | 6 | 17 | 4 |
| ISCED4 | ||||||
| Low/middle | 369 | 45 | 191 | 47 | 178 | 44 |
| High | 443 | 55 | 219 | 53 | 224 | 56 |
| Pubertal status5 | ||||||
| Yes | 354 | 44 | 199 | 49 | 155 | 39 |
Abbreviations: IDEFICS, Identification and Prevention of Dietary- and Lifestyle-Induced Health Effects in Children and Infants; W0, first examination wave; W3, third examination wave.
Iron deficiency defined according to the WHO: children aged <5 y: serum ferritin <12 μg/L; children of 5 y or older: serum ferritin <15 μg/L.
Children were classified as vegetarian if they replied to the specific question to typically exclude meat, poultry, sausage and fish from their diet in the Food Frequency Questionnaire. Some of them however reported later on to occasionally consume meat or fish.
According to Cole and Lobstein [26].
ISCED, International Standard Classification of Education. The highest educational level of the parents was grouped in 2 categories: low/medium (ISCED level 0–4) or high level (ISCED level 5 and 6).
Children were considered pubertal in girls if menarche had already occurred (yes vs. no) and in boys if voice alterations had already started or were completed (yes vs. no) based on self-reported age at menarche and voice mutation status.