Table 2. Characteristics of the study population, stratified by sex, based on mixed linear and mixed logistic regression analyses.
| Total (n = 835) | Males (n = 418) | Females (n = 417) | p-valuea | ||||
|---|---|---|---|---|---|---|---|
| Parameter | M (SD) | M (SD) | M (SD) | ||||
| Age and anthropometry | |||||||
| Age (years) | 9.5 (0.9) | 9.7 (0.9) | 9.4 (0.9) | <0.001 | |||
| Height (cm) | 133.2 (7.1) | 133.3 (6.7) | 133.1 (7.5) | 0.584 | |||
| Weight (kg) | 30.5 (7.5) | 30.0 (6.5) | 31.0 (8.2) | 0.087 | |||
| BMI (kg/m2) | 17.0 (3.1) | 16.8 (2.6) | 17.3 (3.3) | 0.015 | |||
| Physical fitness | |||||||
| VO2 maxb (in ml kg-1 min-1) | 49.1 (4.3) | 50.8 (4.3) | 47.3 (3.5) | <0.001 | |||
| Grip strengthc (in kg) | 12.0 (3.1) | 12.7 (3.1) | 11.4 (2.9) | <0.001 | |||
| Selective attention | |||||||
| E%d | 16.8 (12.9) | 16.4 (13.3) | 17.1 (12.4) | 0.397 | |||
| CPe | 54.5 (30.5) | 53.9 (29.9) | 55.0 (31.2) | 0.486 | |||
| Academic achievement | |||||||
| Academic achievement scoresf | 4.3 (1.5) | 4.0 (1.6) | 4.5 (1.4) | <0.001 | |||
| Sociocultural characteristics | |||||||
| Socioeconomic status (SES)g | 7.2 (2.0) | 7.2 (2.0) | 7.3 (2.0) | 0.778 | |||
| Food securityh | 3.1 (0.9) | 3.1 (0.9) | 3.1 (0.9) | 0.482 | |||
| Prevalence of helminth infection and stunting | n (%) | n (%) | n (%) | ||||
| Infectedi | 333 (31.1) | 182 (32.5) | 151 (29.6) | 0.462 | |||
| Double infectionj | 135 (16.2) | 75 (17.9) | 60 (14.4) | 0.089 | |||
| Stuntedk | 103 (12.3) | 50 (12.0) | 53 (12.7) | 0.535 | |||
All statistically significant differences are marked in bold.
aAll p-values are calculated using either mixed linear or mixed logistic regression, as appropriate, adjusted for clustering of school classes.
bAll mean VO2 estimates are expressed in ml kg-1 min-1 and adjusted for age.
cAll mean grip strength values are expressed in kg and are not adjusted for age.
dE% = Percent of errors.
eCP = Concentration performance.
fAcademic achievement scores: Average of the four subjects Home Language, Additional Language, Mathematics and Life Skills (n = 777)
gSES: Socioeconomic status measured by ownership and housing-related questions on a scale from 0 to 9 points (0 = low score).
hFood security measured with the hunger scale ranging from 0 to 4 (0 = hungry/food insecure, 4 = not hungry/food secure).
iInfected with one or two soil-transmitted helminth species (A. lumbricoides and/or T. trichiura).
jDouble infection: Infected with two soil-transmitted helminth species (A. lumbricoides and T. trichiura).
kStunting is defined as <-2HAZ.