But CT works better than IPT for reducing social anxiety and "should be the preferred psychological treatment" for that indication, said Dr Ulrich Stangier from University of Frankfurt and colleagues in the Archives of General Psychiatry.
The researchers say theirs is the first direct comparison of CT and IPT for outpatients with social anxiety disorder. At two research centres in Germany - one specialising in CT, the other in IPT - they randomly assigned 117 patients to either CT (n = 38) or IPT (n = 38) in 16 individual sessions over 20 weeks, plus one booster session, or to a wait-list control group (n = 41).
According to the investigators, both CT and IPT were associated with significantly greater easing of SAD symptoms compared with no treatment (wait list), and CT was considerably more effective than IPT.
What the study found
On the primary outcome measure, the Clinical Global Impression Improvement Scale, 66% of patients who received CT showed marked improvement in social-phobic symptoms at the 20 week post-treatment assessment, compared with 42% of patients who received IPT and 7% of those in the wait-list control group.
At the one-year evaluation, the CT group still had a significantly higher response rate (68% vs 32%). In addition, patients who received IPT were much more likely to have had additional nonprotocol treatment during follow up.
The pattern was similar when assessors used the Liebowitz Social Anxiety Scale, the Hamilton Rating Scale for Depression, and patient self-ratings of SAD symptoms.
The authors had not expected that CT would be superior to IPT, and they don't know which components of CT might have led to its greater effects.
"Because the two treatments differ with respect to the explicit targets for psychotherapeutic change, CT might tackle aspects that are of greater relevance to the etiology of SAD," they wrote.
They add that it is also possible that interpersonal problems may be more likely to resolve when the underlying dysfunctional cognitions and safety avoidance behaviours are effectively modified.
(Reuters Health, July 2011)