An interesting new ACT study is from Finland:
Lappalainen, R., Lehtonen, T., Skarp, E., Taubert, E., Ojanen, M., & Hayes, S. C. (in press). The impact of CBT and ACT models using psychology trainee therapists: A preliminary controlled effectiveness trial. Behavior Modification
OK, OK. I am an author ... but that was only because I thought it was so cool that I kept helping with the writing. Raimo eventually stuck me on it (thanks Raimo!)
Only a handful of studies have so far directly compared ACT with traditional CBT, so this study is pretty important. 14 trainee therapists were given initial training in CBT (12 hours of lecture; + manuals; + supervision) and ACT (6 hours of lecture; + manuals; + supervision). Outpatients (N = 28) who contacted a university clinic following a newspaper advertisement, were randomized to either approach, with each student therapist treating one CBT and one ACT client. Participants with any normal outpatient problem were included.
Because of the range of client problems in this effectiveness trial, specific procedures were linked to a functional analysis in each case. That took 2 sessions. Then they have 6 to 8 additional sessions applying either the ACt or CBt methods suggested by the functional analysis.
The results suggested that clients who were treated from an ACT model showed more improvement than clients who were treated from a traditional CBT model.
The main outcome variable was the SCL-90 (GSI). The within effect for ACT was large while it was small for CBT. At both post and the 6 month follow up the between group effect size is medium (and significant statistically). Similar results were shown on depression and social functioning.
Here are the SCL-90 data, for example:
Means(sd)
CBT (n = 14)
Pre: 1.21 (.84)
Post: .94 (.65)
F-Up: .96 (.92)
ACT (n = 14)
Pre: 1.16 (.59)
Post: .61 (.38)
F-Up: .62 (.44)
Wilcoxon within:
CBT:
Pre to Post: Z=-1.79(*)
Pre to F-Up: Z=-1.60
ACT:
Pre to Post: Z=-3.17**
Pre to F-Up: Z=-2.92**
* = p .1
** = p .05
The coolest part is that students felt initially less knowledgeable about ACT; they had half as much training as CBT; and were more fearful throughout when it was used while fear subsided in CBT. Yet the outcomes were better.
Process data were also interesting. CBT improved client self-confidence more rapidly than ACT, and ACT improved acceptance more than CBT. Both processes predicted better outcomes; but acceptance remained predictive when controlling for self-confidence but not vice versa.
At follow up ACT participants showed HIGHER self-confidence than CBT participants tho that finding is not actually in the MS.
You can reach Raimo Lappalainen through the site: he is an ACBS member.