Table 1. Admission characteristics of children in the two study groups.
| Variable | SP | Placebo |
| **N = 597 | **N = 598 | |
| Age (months) | ||
| (mean, SD) | 28.4 (18) | 28.7 (19) |
| Sex (male) % | 52.3% | 52.1% |
| Ethnic group | ||
| Mandingo | 228(39%) | 227(38%) |
| Wollof | 74 (13%) | 91 (15%) |
| Fula | 98 (17%) | 96 (16%) |
| Jola | 85 (14%) | 88 (15%) |
| Others | 102 (17%) | 93 (16%) |
| Recruitment centre | ||
| RVTH | 160 (27%) | 166 (28%) |
| MRC | 117 (20%) | 114 (19%) |
| Brikama | 155 (26%) | 152 (26%) |
| Essau | 124 (21%) | 126 (21%) |
| Sibanor* | 36 (6%) | 36 (6%) |
| Previous chloroquine treatment (%) | 62.4 | 60.6 |
| Educational attainment of mother (years in school), (mean, SD) | 2.1 (5.7) | 2.0 (3.6) |
| Resp rate/min (mean, SD) | 40.0 (13) | 39.3 (12) |
| Mean haemoglobin g/dl (SD) | 5.1 (1.2) | 5.2 (.053) |
| Temp °C (mean, SD) | 37.5 (0.91) | 37.56 (.88) |
| Pulse rate/min (mean, SD) | 121 (21) | 120 (21) |
| Splenomegaly (%) | 19.8 | 24.7 |
| Hepatomegaly (%) | 26.7 | 27.2 |
| Proportion with malaria parasitaemia | 62% | 61% |
| Geometric mean density (95% CI) IQR | 17710 (136223, 23024) (0, 51000) | 15296 (11668, 20050) (0, 47600) |
| Sleeps nightly under intact or impregnated net# | 20.7 | 15.3 |
*Recruitment only during year 2.
**Data missing for 2 and 3 subjects in the placebo and SP groups respectively.
#bednet use was determined at the end of the transmission season.