Mis-selling of the Cognitive Therapy Rating Scale

If your performance has been evaluated using the cognitive therapy rating scale (or the revised version) you may have a claim for ‘damages’. Curiously the cognitive therapy rating scale has a shaky foundation:

  1. The CTRS has only been evaluated in a sample of depressed clients undergoing cognitive therapy [Shaw et al (1999)] , therapists scores on this did not  predict outcome on self-report measures the Beck Depression Inventory or the SCL-90 (a more general measure of psychological  distress) however it did predict outcome on the clinician administered Hamilton Depression Scale predicting just 19% of the variance in outcome, but it was the structure parts of the scale (setting of an agenda, pacing, homework) that accounted for this 19% not items measuring socratic dialogue etc. The authors concluded: ‘The results are, however, not as strong or consistent as expected’
  2. There is no evidence that the CTRS is applicable to disorders other than depression. Some aspects of the CTRS such as socratic dialogue may be particularly inappropriate with some clients e.g OCD and PTSD sufferers.
  3. The CTRS does not make it clear that the clinician cannot have set an appropriate agenda without reliably determining what the person is suffering from.
  4. In practice raters appear to pay more attention to the socratic dialogue item as opposed to interpersonal effectivenes (e.g non-verbal behaviour). There is a poor intra class correlation of the order 0.1, ratings of least competent therapists are more in agreement with those of supervisors than the more competent therapists! [McManus et al (2012)]
  5. The Hamilton Scale used in the Shaw et al (1999) study was developed before the development of DSM criteria and it is questionable about whether any correlation would be found between DSM diagnostic status and score on the CTRS for depression or indeed any disorder.

 

Dr Mike Scott