When is evidence based practice not evidence based practice?

When it is not using the latest evidence. An article in the Cognitive Behaviour Therapist, much lauded by the Editor of the Journal, highlights this. There was no review of the latest group CBT for PTSD outcome studies see Scott (2022) Personalising Trauma Treatment: Reframing and Reimagining London: Routledge. Instead the authors relied upon the conflicted, dated, recommendations of guideline producers. Guidelines are  produced by Committee decisions with all the vagaries that entails, they are not the results of a systematic analysis of data. My book includes  a review of group CBT outcome studies for PTSD (reproduced at the end of this blog), indicating the inferiority of a group approach.


In this study of group CBT for PTSD, the results of 3, 8 session (2hrs per session) group programmes are summarised by the treating IAPT workers. But no standardised diagnostic interview was used at any point, so it is unknown what proportion of people lost their diagnostic status for how long. Nor whether they were truly suffering from PTSD in the first place, making independent replication impossible. It is claimed that the treatment was given to those who ‘preferred’ group therapy but this is disingenuous. In practice people are offered more immediate treatment with a group or a long wait for individual therapy, whilst they may opt for the former, it is not a preference. 

8 is The New Magic Number

The tail is wagging the dog, in that the authors have fitted in with the growing fetish for 8 sessions. Those who complete IAPT treatment typically have 7.5 sessions. Further NICE recommend, 8 group CBT therapy sessions for depression as the first line treatment for depression. But there is no empirical evidence that 8 sessions of anything makes a real-world difference. It is simply what the powers that be have decided to ration out. There is no indication of the mechanism of action of 8 sessions. If it is not possible to specify how a claimed result is achieved then the latter is suspect. BABCP has just celebrated its 50th birthday by a return to magic.

Group Treatments

Groups are an attractive option for service providers, offering the prospect of reduced waiting lists and greater access to therapy. But comparisons of group interventions show them to be inferior to individual therapy post-trauma and to offer no added benefit to treatment as usual. Kearney et al. (2021) compared the effectiveness of group cognitive processing therapy (CPT) for the treatment of PTSD with group loving-kindness meditation (LKM) which involved the silent repetition of phrases intended to elicit feelings of kindness for oneself and others. The proportion of veterans who lost their diagnostic status i.e. who no longer suffered from PTSD did not differ at the end of treatment (CPT – 29%, LKM – 27.5%). Each intervention consisted of 12 weekly 90-minute group sessions but the mean number sessions completed was only six in CPT and seven in LKM. Resick et al. (2017) found that in a population of veterans group CPT was inferior to individual CPT. Preparatory group treatment for CPT or prolonged exposure does not enhance outcome. Dedert et al. (2020) examined whether a preparatory group with a focus on psychoeducation, coping skills, sleep hygiene and an introduction to PTSD treatment options added benefit to the trauma-focussed interventions, it did not. Further, those who went through a preparatory group did less well than those who did not in whatever trauma-focussed CBT they went onto in terms of PTSD symptom reduction. There is no evidence that initial Stabilisation Groups contribute to treatment effectiveness. However, the aforementioned studies were all on veterans, so care has to be taken in generalising from the results. But a study by Mahoney et al. (2020) of women prisoners who reported a history of interpersonal violence and trauma found that a ten-session group psychoeducational programme, Survive and Thrive, conferred no benefit over treatment as usual.

There appears to be no benefit to a phase-based approach, in which the first phase has as its goal safety and stabilisation, despite the inherent attractiveness of this option.

Scott, Michael J. Personalising Trauma Treatment (p. 293). Taylor and Francis. Kindle Edition.



Is Evidence Based Treatment Possible Without Evidence Based Assessment?

‘no’, this is the take home message from a just published study by Moses et al in the Journal of Anxiety Disorders https://www.sciencedirect.com/science/article/pii/S0887618520300931. An evidence based assessment includes a diagnostic interview, as well as a clinical interview and psychometric tests. Moses et al (2020) summarise the literature that the inclusion of a diagnostic interview improves outcome, by minimising missed diagnosis and misdiagnosis. These authors bemoan their finding that only a small minority of Australian psychologists use a diagnostic interview, but the position is even worse in the UK, as the largest provider of services the Improving Access to Psychological Therapies (IAPT) explicitly excludes the making of diagnosis/diagnostic interviews.   IAPT cannot improve access to evidence based psychological therapies because it does not operate the admission gate of an evidence based assessment.

The absence of an EBA leads to a revolving door, demoralising clients in search of a credible explanation of their difficulties. An EBA is a necessary part of evidence based practice (EBP) in that it highlights candidate evidence supported treatments (ESTs). But clinical judgement is still required to ascertain whether there is a sufficient match between client and the subjects in the EST. Most ESTs have admitted clients to the study with a limited range of comorbid disorders and have not been cognitively impaired, or suffering debilitating pain. Further the clients in the EST have been in a safe environment. 


Dr Mike Scott