Comparing the two scales in the Spielberger methodology provides a deeper understanding. If you have high state anxiety but low trait anxiety, you are simply going through a difficult period. If both are high, anxiety is a stable personality trait.
The score on the state anxiety scale can change within an hour if your environment changes. However, the trait anxiety score typically remains stable, as it reflects the fundamental characteristics of your psyche.
The STAI inventory is universal. It is suitable for adults and adolescents (from 14-15 years old),athletes for assessing pre-competition states, and anyone who wants to understand if their worry is a temporary factor or a personality trait.