Table 2.
Primary exposures (geohelminth infections) | Outcome | Sample size available | Analysis sample size | Exposure prevalence | Expected prevalence of outcomes (exposed vs. unexposed groups) |
Α | Power |
---|---|---|---|---|---|---|---|
Maternal | Vaccine antibodies @ 7 mths | ||||||
Hib | 2,300 | 1,000 | 50% | 65% vs. 75% | 0.01 | 80% | |
Rotavirus | 2,300 | 1,000 | 50% | 40% vs. 60% | 0.01 | > 99% | |
Maternal | Vaccine antibodies @ 2 yrs | ||||||
TT | 1,955 | 1,000 | 50% | 85% vs. 95% | 0.01 | > 99% | |
HBV | 1,955 | 1,750 | 50% | 80% vs. 85% | 0.05 | 80% | |
OPV type 3 | 1,955 | 500 | 50% | 80% vs. 95% | 0.01 | > 99% | |
Infant | Vaccine antibodies @ 5 yrs | ||||||
TT | 1,725 | 1,000 | 35% | 60% vs. 80% | 0.01 | 99% | |
HBV | 1,725 | 1,500 | 35% | 70% vs. 80% | 0.01 | 95% | |
OPV type 3 | 1,725 | 1,000 | 35% | 50% vs. 70% | 0.01 | > 99% | |
Maternal | SPT @ 3 years | 1,840 | 1,840 | 50% | 15% vs. 25% | 0.01 | 99% |
Infant | SPT @ 3 years | 1,840 | 1,840 | 35% | 15% vs. 25% | 0.01 | > 99% |
Maternal | Eczema @ 3 years | 1,840 | 1,840 | 50% | 25% vs. 35% | 0.01 | 99% |
Maternal | Asthma @ 5 years | 1,725 | 1,725 | 50% | 17% vs. 23% # | 0.05 | 86% |
Infant | Asthma @ 5 years | 1,725 | 1,725 | 35% | 17% vs. 23% # | 0.05 | 83% |
Infant | Asthma @ 5 years | 1,725 | 1,207 | 20% | 25% vs. 15% # | 0.01 | 93% |
Random samples of the study population will be selected for analysis of the protective levels of vaccine antibodies. Based on data from the cohort we estimate that 20% of children will have allergen skin test reactivity to any allergen at 5 years, that 30% of children will have at least one documented episode of eczema by 3 years of age and that 20% of children will have asthma at 5 years. Based on data from the cohort we estimate that ~50% of mothers are infected with any geohelminth parasite and ~30% of children will have at least one documented geohelminth infection during the first 2 years of life.
#-expected effects of geohelminth infections on asthma prevalence using data from cross-sectional analyses in Ecuador [58] and Brazil [59].