Sample characteristics (n=423)
| Variable name | N | Statistic |
| Demographics | ||
| Age, mean (SD) | 423 | 10.5 (0.9) |
| Gender (%) | ||
| Female | 238 | 57.2 |
| Race (%) | ||
| African | 159 | 44.2 |
| Coloured* | 82 | 22.8 |
| Indian | 99 | 27.5 |
| White | 20 | 5.6 |
| Caregiver education (%) | ||
| Less than high school | 129 | 39 |
| High school graduate | 144 | 43.5 |
| More than high school | 56 | 16.9 |
| Refused | 2 | |
| Total annual household income (%) | ||
| <US$1500 | 57 | 28.2 |
| US$1501–4500 | 54 | 26.8 |
| US$4501–8000 | 43 | 21.3 |
| US$8001 and above | 48 | 23.7 |
| Child’s health outcomes | ||
| Asthma severity (%) | ||
| Moderate to severe | 27 | 7.2 |
| Mild persistent | 46 | 12.3 |
| Mild Intermittent | 74 | 19.7 |
| None | 228 | 60.8 |
| Airway hyperresponsiveness (%) | ||
| Marked | 29 | 9.6 |
| Probable | 21 | 7 |
| Possible | 31 | 10.3 |
| None | 221 | 73.2 |
| Technician derived FEV1 (mean (SD)) | 369 | 1.74 (0.39) |
| Airwatch obtained FEV1 (Mean (SD)) | 423 | 1.6 (0.5) |
| Airwatch obtained peak expiratory flow (mean (SD)) | 423 | 275.2 (69.7) |
| Atopy,% yes | 136 | 38.7 |
| Caregiver smokes, % | 105 | 28.5 |
| Mean number of smokers in household (mean (SD)) | 344 | 0.9 (1.0) |
| Households with one or more smokers (%) | 242 | 27.2 |
*‘Coloured’ people were defined as those of mixed ethnicity, based on the old racial classification system in South Africa. Although no longer a legal definition, ‘race’ or ethnicity still substantially predicts socioeconomic status in the country.