Table 1 Variables used to understand the impact of SP interventions on head circumference among 6720 live newborns, born between May and November 2015

Head_circum

Head circumference, at birth, in mm

n = 6720

Continuous

Girl

1 = Female

n = 6712

0 = Male

SPFREQ

0,1,2, 3 + doses of SP

n = 6720

Intervention

1 = DANGE SHUNI, Goronyo or Silame LGA, where community based SP distribution occurred

n = 6720

0 = Yabo, where no community based SP distribution occurred

Primi

1 = Primigravida

n = 6711

0 = Multigravida

Month of birth

April–November 2015

In the unadjusted analyses, all earlier months are compared to November. In the adjusted analyses, this variable was used as a continuous variable

n = 6720

Gestational age at birth (months)

2 = 10

n = 6719

1 = 9

0 = 8