Following relapse after 11 sessions of cognitive behavioral treatment
of panic disorder, a client wore an ambulatory physiological monitorin
g device for 1 day. The physiological data were used to test the clien
t's hypothesis that panic attacks always occur from ''out of the blue.
'' Results showed that hyperventilation and fearful thoughts preceded
panic attacks, refuting the client's initial hypothesis. A comparison
of the client's self-report data before and after wearing the device i
ndicated that this therapeutic strategy had a beneficial treatment eff
ect. The results' are discussed in the context of the scientist-practi
tioner approach to treatment failure.