Table 1.

Demographic characteristics of participants by duration of study attendance (columns), showing percentage or median, as appropriate

Duration of parameter	Enrolled	Attending	Completed
Number under study	1981	1497	834
Mothers
Married	90.2%	90.1%	90.3%
HIV+	17.5%	19.3%	18.6%
Median age	25 (21–29)	25 (22–29)	25 (22–30)
Median infants in house (<1 year)	1 (1–1)	1 (1–1)	1 (1–1)
Median children in house (<5 years)	2 (1–2)	2 (1–2)	2 (1–2)
Infants
Born at Chawama PHC	56.9%	56.7%	58.2%
Born at University Teaching Hospital	34.8%	35.5%	34.3%
Female sex	46.9%	46.4%	46.4%
Received BCG at birth	46.4%	46.6%	46.2%
Received OPV at birth	33.4%	32.4%	27.7%
Median birth weight (kg)	3 (2.8–3.3)	3 (2.8–3.3)	3.1 (2.8–3.3)

IQR is shown in parentheses. Attending mother–infant pairs attended one or more scheduled clinic visit. Completed individuals attended all six scheduled visits.

OPV, oral polio vaccine; PHC, Primary Health Clinic.