Table 1 Estimation of minimum sample sizes in Nairobi and Abidjan

\({Z}_{1-\propto /2}\) (95% level of confidence)

1.96

1.96

Expected prevalence rate (\(P\))

0.20

0.15

Design effect (\({D}_{eff}\))

1.50

1.50

Margin of error (\(e\)²)

0.05

0.05

Unadjusted sample size (minimum number of individuals)

369

294

Proportion of children under the age of 5 years

0.12¹

0.15²

Number of people needed given the proportion of children under 5 years

3073

1959

Average household size (number of individuals)

3.0¹

4.5²

Expected valid response rate

0.9

0.9

Adjusted sample size (minimum number of households)

1138

484