Table 4.
Baseline characteristics, stratified by vitamin D status, of the study population of children aged 6–36 months (n 516) residing in five low-SES peri-urban neighbourhoods near Quito, Ecuador, June–July 2003
| <42·5 nmol/l (n 96) | ≥42·5 nmol/l (n 420) | ||||
|---|---|---|---|---|---|
| Variable | n | Mean or n | sd or % | Mean or n | sd or % |
| Demographic and household characteristics | |||||
| Age (months), mean and sd | 516 | 18·4 | 7·7 | 17·7 | 8·1 |
| Age group, n and % | |||||
| 6–12 months | 134 | 19 | 19·8 | 115 | 27·4 |
| >12 months | 382 | 77 | 80·2 | 305 | 72·6 |
| Sex, n and % | 516 | ||||
| Male | 261 | 50 | 52·1 | 211 | 50·2 |
| Female | 255 | 46 | 47·9 | 209 | 49·8 |
| Maternal education, n and % | 377 | ||||
| Illiterate | 34 | 5 | 7·3 | 29 | 9·4 |
| Primary school | 190 | 38 | 55·9 | 152 | 49·2 |
| High school or higher education | 153 | 25 | 36·8 | 128 | 41·4 |
| Paternal education, n and % | 361 | ||||
| Illiterate | 27 | 4 | 6·2 | 23 | 7·8 |
| Primary school | 179 | 34 | 52·3 | 145 | 49·0 |
| High school or higher education | 155 | 27 | 41·5 | 128 | 43·2 |
| Crowding, mean and sd | 369 | 2·5 | 1·5 | 2·7 | 1·6 |
| Household ownership, n and % | 381 | ||||
| Own | 193 | 38 | 55·9 | 155 | 49·5 |
| Rent | 119 | 14 | 20·6 | 105 | 33·6 |
| Other | 69 | 16 | 23·5 | 53 | 16·9 |
| Access to sanitary facilities, n and % | 380 | ||||
| Access to toilet | 190 | 33 | 48·5 | 157 | 50·3 |
| No access to toilet | 190 | 35 | 51·5 | 155 | 49·7 |
| Water source, n and % | 381 | ||||
| Potable | 159 | 38 | 55·9 | 121 | 38·7 |
| Non-potable | 222 | 30 | 44·1 | 192 | 61·3 |
| Anthropometric measures | |||||
| Weight (kg), mean and sd | 516 | 9·0 | 1·6 | 9·2 | 1·9 |
| Height (cm), mean and sd | 516 | 74·4 | 7·0 | 74·9 | 7·8 |
| WAZ, mean and sd | 516 | −1·6 | 0·9 | −1·4 | 1·0 |
| WAZ category, n and % | |||||
| Normal weight | 179 | 22 | 22·9 | 157 | 37·4 |
| Underweight | 337 | 74 | 77·1 | 263 | 62·6 |
| HAZ, mean and sd | 516 | −2·6 | 1·1 | −2·3 | 1·2 |
| HAZ category, n and % | |||||
| Not stunted | 195 | 20 | 20·8 | 175 | 41·7 |
| Stunted | 321 | 76 | 79·2 | 245 | 58·3 |
| WHZ or WLZ, mean and sd | 516 | −0·26 | 0·89 | −0·21 | 0·97 |
| WHZ or WLZ category | |||||
| Normal weight-for-height/length | 411 | 78 | 81·3 | 333 | 79·3 |
| Mildly wasted | 89 | 15 | 15·6 | 74 | 17·6 |
| Wasted | 16 | 3 | 3·1 | 13 | 3·1 |
| Laboratory measures | |||||
| 25(OH)D (nmol/l)*, mean and sd | 516 | 35·0 | 5·7 | 63·2 | 15·0 |
| iPTH (pmol/l), mean and sd | 396 | 2·1 | 1·6 | 1·9 | 1·5 |
| Hb (g/l), mean and sd | 491 | 12·1 | 1·0 | 12·0 | 1·2 |
SES, socio-economic status; WAZ, weight-for-age Z-score; HAZ, height-for-age Z-score; WHZ, weight-for-height Z-score; WLZ, weight-for-length Z-score; 25(OH)D, 25-hydroxyvitamin D; iPTH, intact parathyroid hormone.
*
To convert units of 25(OH)D from nmol/l to ng/ml divide by 2·496.