Table 2.
Summary statistics on parental surnames, altitude, birth order, maternal education, maternal age, and offspring anthropometry z scores for the highland and lowland study samples
| Variables | Highland | Lowland | ||||
|---|---|---|---|---|---|---|
| Categorical | n | % | Regression categorya | n | % | Regression category |
| No. indigenous parental surnames | ||||||
| 0 | 12 | 9 | 56 | 33 | ||
| 1 | 39 | 29 | 68 | 41 | ||
| 2 | 40 | 30 | 35 | 21 | ||
| 3 | 32 | 24 | 5 | 3 | ||
| 4 | 10 | 8 | 3 | 2 | ||
| Birth order | ||||||
| 1 | 40 | 30 | 84 | 50 | ||
| 2 | 29 | 22 | 51 | 31 | ||
| 3 | 19 | 14 | 20 | 12 | ||
| 4+ | 45 | 34 | 12 | 7 | ||
| Maternal education | ||||||
| None, illiterate | 23 | 17 | 1 | 0 | 1 | |
| None, literate | 2 | 2 | 1 | 0 | 1 | |
| Primary, incomplete | 70 | 53 | 2 | 3 | 2 | 1 |
| Primary, complete | 30 | 22 | 3 | 6 | 4 | 1 |
| Secondary, incomplete | 4 | 3 | 3 | 29 | 17 | 1 |
| Secondary, complete | 3 | 2 | 3 | 68 | 41 | 2 |
| Postsecondary, incomplete | 0 | 0 | 3 | 25 | 15 | 3 |
| Postsecondary, complete | 1 | 1 | 3 | 36 | 22 | 4 |
| Continuous | Mean | SD | Mean | SD | ||
| Maternal age at birth of child (yrs) | 25.1 | 7.6 | 26.4 | 6.3 | ||
| Median | IQR | |||||
| Altitude measured (m) | 3,730 | 3,320–3,830 | – | – | ||
a
Regression Category" indicates how original categories were recoded for the purpose of the regression model: categories with small numbers of cases were combined.