The differential stability of state and trait test anxiety was investi
gated in two content areas (Psychology, n = 154; Method, n = 133). The
structural model supported the hypothesis regarding differential stab
ility of individual differences for state and trait test anxiety over
a three-month interval, with trait test anxiety being more stable than
state test anxiety. Contrary to the invariant stability of trait test
anxiety across content, the stability of state test anxiety was signi
ficantly low in Psychology as compared to that in Method, indicating t
hat more individuals in the Psychology group reported fluctuant state
test anxiety over time. Although the stability of individual differenc
es in state test anxiety was low, the factor structures of state test
anxiety at two occasions were invariant, supporting the contention tha
t even when the factorial structures are stable over time and the test
-retest stability is high, individual state test anxiety may be unstab
le across time.