Adoptieratio

Adoptieratio is a statistical metric used in sociology and demography to measure the share of individuals in a population who are adopted. It describes adoption prevalence within a defined group, such as a birth cohort or geographic area.

Calculation: adoptieratio = number of adopted individuals in the group divided by the total number of individuals in that group. Analyses may distinguish at-birth, foster-to-adopt, and international adoptions, either aggregating or disaggregating them.

Data and definitions: Estimates rely on child welfare records, adoption registries, censuses, and surveys. Definitions of being "adopted" vary by jurisdiction, affecting comparability; some studies include permanent guardianship while others do not.

Variants: Age-specific adoptieratio tracks adoption status by age; generational adoptieratio compares successive generations. Temporal analyses examine changes over time or in response to policy changes.

Applications: Used in demographic research, policy evaluation, and resource planning for child welfare services. It supports cross-regional comparisons of adoption prevalence and assessment of long-term outcomes for adoptees.

Limitations: Data quality and privacy constraints, non-uniform definitions, and underreporting can limit comparability. Small populations yield unstable estimates, and unpublished or informal adoptions may be missed.

See also: Adoption rate, Child welfare statistics, Demographic measures.