The recommended measure for SDG 4.2.1 is the Early Childhood Development Index 2030 (ECDI2030) which is a 20-item instrument to measure developmental outcomes among children aged 24 to 59 months in population-based surveys. The indicator derived from the ECDI2030 is the proportion of children aged 24 to 59 months who have achieved the minimum number of milestones expected for their age group, defined as follows:
-Children age 24 to 29 months are classified as developmentally on-track if they have achieved at least 7 milestones;
-Children age 30 to 35 months are classified as developmentally on-track if they have achieved at least 9 milestones;
-Children age 36 to 41 months are classified as developmentally on-track if they have achieved at least 11 milestones;
-Children age 42 to 47 months are classified as developmentally on-track if they have achieved at least 13 milestones;
-Children age 48 to 59 months are classified as developmentally on-track if they have achieved at least 15 milestones.
UNESCO Institute for Statistics
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