Table 1.

Sample size estimates for effect of pre- and peri-conception intervention package alone A + B vs C + D) or Enhanced antenatal, postnatal and early childhood care alone (A + C vs B + D)

	Main effect size	Sample size per two groups
Linear growth at 24 months
- Mean length-for-age z-score (LAZ)	0.15 SD (absolute value 0.65 cm at 24 mo)	935
- Proportion stunted (30%)	25% relative reduction	772
Birth weight/birth length	0.15 SD (absolute value 75 g birth weight and 0.35 cm birth length)	935
Proportion LBW (25%)	25% relative reduction	918
Preterm birth (12%) [35]	25% relative reduction	2193
SGA at birth (36%) [10]	25% relative reduction	558

90% power and 95% confidence level for all outcomes