Effectiveness of cognitive-behavioural, person-centred and psychodynamic therapies as practised in UK National Health Service settings.
BACKGROUND
Psychotherapy's equivalence paradox is that treatments have equivalently positive outcomes despite non-equivalent theories and techniques. We compared the outcomes of contrasting approaches practised in routine care.


METHODS
Patients (n = 1309) who received cognitive-behavioural therapy (CBT), person-centred therapy (PCT) and psychodynamic therapy (PDT) at one of 58 National Health Service (NHS) primary and secondary care sites in the UK during a 3-year period completed the Clinical Outcomes in Routine Evaluation-Outcome Measure (CORE-OM) at the beginning and end of their treatment. Therapists indicated which treatment approaches were used on an End of Therapy form. We compared outcomes of six groups: three treated with CBT, PCT or PDT only, and three treated with one of these plus one additional approach (e.g. integrative, supportive, art), designated CBT+1, PCT+1 or PDT+1 respectively.


RESULTS
All six groups averaged marked improvement (pre-post effect size = 1.36). Treatment approach and degree of purity ('only' vs. '+1') each accounted for statistically significant but comparatively tiny proportions of the variance in CORE-OM scores (respectively 1% and 0.5% as much as pre-post change). Distributions of change scores were largely overlapping.


CONCLUSIONS
Results for these three treatment approaches as practised routinely across a range of NHS settings were generally consistent with previous findings that theoretically different approaches tend to have equivalent outcomes. Caution is warranted because of limited treatment specification, non-random assignment, lack of a control group, missing data and other issues.
Department of Psychology, Miami University, Oxford, OH 45056, USA. stileswb@muohio.edu
William B
WB
Stiles
Michael
M
Barkham
Elspeth
E
Twigg
John
J
Mellor-Clark
Mick
M
Cooper
D000328:Adult; D015928:Cognitive Behavioral Therapy / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D001523:Mental Disorders / Q000628:therapy*; D008605:Mental Health Services / Q000592:standards*; D008875:Middle Aged; D018802:Patient-Centered Care / Q000379:methods*; D011613:Psychotherapy / Q000379:methods; D012960:Socioenvironmental Therapy / Q000379:methods*; D013222:State Medicine / Q000592:standards; D016896:Treatment Outcome; D006113:United Kingdom