382 TREATMENT OF SPECIFIC ANXIETY DISORDERS
sessions of cognitive therapy, fluoxetine (Prozac) plus self- exposure, or placebo pill plus
self- exposure (D. M. Clark et al., 2003). At 8 weeks midtreatment and then 16 weeks
posttreatment, cognitive therapy was superior to the fluoxetine and placebo groups.
Cognitive therapy produced very large effect sizes whereas medication produced only
small effect sizes. At 12-month follow-up cognitive therapy remained superior to fluox-
etine. Furthermore, the effects of cognitive therapy were quite specific to social anxiety
given that the three groups did not differ at posttreatment on general mood measures.
In another study 62 patients with social phobia (88% had a generalized subtype)
were randomly assigned to 14 weeks of individual cognitive therapy, exposure plus
applied relaxation training, or a wait list control (D. M. Clark et al., 2006). At posttreat-
ment both interventions were superior to the wait list condition but cognitive therapy
was significantly more effective than exposure plus applied relaxation at posttreatment,
3-month, and 6-month follow-up. Other studies have also reported significant treat-
ment effects for CBT of social phobia that includes both cognitive restructuring and
exposure (e.g., Davidson et al., 2004; Herbert, Rheingold, Gaudiano, & Myers, 2004;
Mörtberg, Karlsson, Fyring, & Sundin, 2006). Overall these studies indicate that cogni-
tive therapy produces clinically significant reductions in social anxiety for the majority
of individuals, even those with more severe generalized social phobia, and the gains are
maintained after treatment termination (see also Rodebaugh et al., 2004). Moreover,
cognitive therapy may produce more enduring effects than medication alone (Hollon
et al., 2006), although medication may be slightly more effective in the short term (see
Rodebaugh et al., 2004).
A number of studies have examined factors within cognitive therapy that may influ-
ence its effectiveness. As noted previously, individual cognitive therapy may be more
effective than a group format and it would appear that the therapy has less impact on
general psychopathology or mood state. Moreover, there is some evidence that individu-
als with social phobia who have a comorbid depression may show a poorer response to
treatment (Ledley et al., 2005). More recently, Hofmann and colleagues found that sud-
den gains occurred in 15% of individuals in their group CBT condition, with the fourth
and 11th sessions the modal points in which this occurred (Hofmann, Schulz, Meuret,
Moscovitch, & Suvak, 2006). However, sudden gains were not associated with better
treatment outcome nor were they more likely to be preceded by significant cognitive
change.
One question that deserves special mention is the debate over the additive benefits
of cognitive restructuring beyond exposure alone in the treatment of social phobia. In
one of the first studies to address this question, Mattick and Peters (1988) found that
therapist- assisted exposure plus cognitive restructuring was more effective for treatment
of severe social phobia than therapist- assisted exposure alone (see Feske & Chambless,
1995, for contrary conclusion). More recently Hofmann (2004b) randomly assigned 90
individuals with social phobia to receive 12 weekly sessions of group CBT, exposure
group therapy (EGT) without explicit cognitive interventions, or a wait list control. At
posttreatment the CBT and EGT conditions produced similar treatment effects that
were significantly greater than the wait list control. However, at 6-month follow-up
only the CBT participants showed continued improvement after treatment termination.
These findings suggest that interventions aimed at directly changing faulty cognition
may produce more enduring treatment benefits for social anxiety. In addressing this
topic Rodebaugh et al. (2004) warned that comparing the added benefits of cognitive