Comorbidity

An announcement by the Beck Institute calls attention to a research finding from Exeter that at first sight looks unsurprising: better therapists are able to treat more complex conditions. Put like that, it does seem unsurprising, but it has profound implications for CBT in the UK.

A couple of the ideas underlying this research are far from obvious, and far from being generally accepted in the UK.

Better and worse

One is the idea that there are better therapists and worse therapists, that therapists’ competence can be measured, and that it is useful to measure it. In the UK there are no routine measurements of therapists’ competence, or of their success rates. On the contrary, there is a false assumption that “CBT is CBT” no matter who provides it.

The only generally-available measure of a therapist’s competence is whether the therapist is accredited or not. Accredited therapists appear in the CBT Register, where anyone can look them up by surname.

Accreditation is not guarantee of actual competence, though. It is quite possible for therapists to become accredited with very little skill, because the accreditation process is entirely based on knowledge and experience, and not at all on skill.

Amongst unaccredited therapists, both in the NHS and in the private sector, there seem to be many who lack even basic abilities like being able to form close therapeutic alliances with their patients, and being able to make sense of common cognitive distortions.

Simple and complex

The second non-obvious idea is that the complexity of mental illness can be measured, and that it is useful to measure it. Again, there is often a false assumption — that the severity of symptoms is the only important thing to measure.

Severity of symptoms is not a particularly useful measure in CBT, because the progress of CBT is essentially the same for severe symptoms as for mild symptoms. Severe symptoms might disrupt therapy and make it take longer, but they do not influence the nature of CBT.

Complex illness, on the other hand, needs a different approach, because the cognitive distortions that have to be addressed are more difficult to discover. It’s this difficulty that links more complex illness with more competent therapists.

The way complexity is measured is crude. It relies on the standard diagnoses. If a patient’s symptoms all fall within a single diagnosis, then that’s a simple illness. If a patient’s symptoms seem to indicate more than one diagnosis, then that’s a complex illness. These extra diagnoses are described in the jargon as ‘comorbid’. There’s no good reason for using such a silly word, which adds nothing to the meaning.

Usefulness

I wrote that these things are useful to measure. Here’s how.

Suppose you provide a mental health service, and you know how competent your therapists are. For example, let’s say there are five therapists and they have competence ratings from 2 to 6. On a chart they look like:

Now let’s say there are five patients and their illnesses have complexity scores that happen to go from 2 to 6 too:

If you know the therapists’ ratings and the patients’ scores, then you can match them up like this:

You can see that each patient gets a therapist whose competence is a match for the complexity of their illness. All these patients can be treated successfully:

If you don’t have the therapists’ ratings and the patients’ scores, then the best you can do is make a random allocation. Some patients will not be treated successfully. Your service as a whole will do less well because of the inevitable mismatch:

Worse than that

More realistically, it’s clear that in the real world therapists are not competent enough to treat the most complex cases. Some therapists have little training, and many others only have book learning without real skills. The ideal match between therapists’ competence and patients’ illnesses is unrealistic because, taken overall, therapists are not competent enough.

To represent this in the model, let’s downgrade the therapists so that their skill levels go from 1 to 5. Matching patients to therapists again in the same simple way has terrible consequences:

This is what you see in some NHS trusts. At every level, therapists are struggling with patients they cannot treat. Patients cannot be referred to better therapists who would be able to treat them because those better therapists are blocked by even more complex cases.

When it’s just coloured bars on a chart, the solution seems very simple — move all the patients along one step to the right:

This gives an 80% success rate for the same patients and the same therapists!

Why not

Why does this not happen? You can see the two reasons at the ends of the chart.

At the right you can see a patient who just cannot be treated at all. The NHS seems to have no concept of a mental illness that is untreatable because of its complexity. There’s no NHS assessment in which one of the outcomes is: “just cannot be treated at all.”

At the left you can see a therapist who is not competent enough to treat anyone. Again, the NHS seems to have no concept of this. There are no NHS staff going around saying, “I tried to be a CBT therapist, but I didn’t make the grade.” There’s no grade. Everyone can do CBT, no matter how bad they are.

In the private sector it’s different. Private patients with untreatable illnesses have limited resources, so they really do end up without any treatment at all. Private therapists who are not competent enough really do go out of business — some of them get jobs in the NHS.

So research like this points the way to more rational and effective treatments for mental illness in the far future.

About these ads