Analytical approach:
The analysis was based on one two-year study. The authors did not state the perspective.
Effectiveness data:
The clinical outcome data were retrieved retrospectively two years after delivery, from mothers who had participated in a randomised controlled trial (RCT) of women receiving either vitamins C and E or placebo, during pregnancy. A sample of 643 women, with 330 in the intervention group and 313 in the placebo group, was considered for the respiratory outcomes; and a sample of 99 women, with 54 in the intervention group and 45 in the placebo group, was considered for the health care use data. The primary clinical outcomes were the occurrence of asthma, eczema, cough, or wheeze. Regression models were used to adjust for differences in baseline characteristics, and for twins and triplets.
Monetary benefit and utility valuations:
Not relevant.
Measure of benefit:
The summary benefit measure was the proportion of infants with any symptoms of asthma, eczema, cough, or wheeze.
Cost data:
The cost categories were the medications, hospital in-patient and out-patient services, general practitioner (GP) and community practitioner visits, and the use of home oxygen. The resource use was from GP and hospital records. The costs were based on NHS tariffs and were reported in UK pounds sterling (£).
Analysis of uncertainty:
Confidence intervals around the outcomes were obtained from the regression models. A nonparametric bootstrap method was used for the economic data, which were not normally distributed.