Table 4: Within-group comparisons of the proportion of plasma samples with detectable concentrations of unmetabolized folic acid.

McNemar’s S

1.1 mg group
 Week 0 versus week 67.0010.008
 Week 0 versus week 127.0010.008
 Week 0 versus week 301.0010.32
5 mg group
 Week 0 versus week 66.0010.014
 Week 0 versus week 126.0010.014
 Week 0 versus week 301.0010.32

aCritical value = 0.0167 after Bonferroni correction for 3 pair-wise comparisons within each group (0.05 ÷ 3 = 0.0167).