What is the definition of age identity? How to measure it?

Most welcome!

Thank you from the bottom of my heart.

Age identity refers to the subjective sense of age that individuals feel, which may differ from their chronological age. It reflects the age category with which a person identifies, such as "young adult" or "old person".

Age identity can be measured in several ways:

Single-item measure: Individuals choose the age category that best suits them.

Semantic differential procedure: Individuals rate themselves and age referents (e.g., "An Old Person", "A Middle-Aged Person") on bipolar adjectives.

Comparing subjective age to chronological age: Calculating the absolute and relative differences between the two.

These measures provide insights into individuals' age identities and their relationship to various physical, mental, and social outcomes.