Outcomes help map out evidence in an uncertain terrain, but they are relative
Authors: Tim Kendall
Journal: World Psychiatry (2019)

It is a testament to P. Cuijpers' intellectual courage that he opens his paper1 by stating that we do not really know what we mean by “mental disorder” , and that we are not sure about what really constitutes a psychological treatment or underpins its effectiveness. He ends by pointing out that the outcomes of whatever we are treating with whatever means we have all depend upon the perspective we take, whether we are a patient, a clinician or anyone else. These are the uncertainties we are working with in psychotherapy, in mental health and, I suspect, in health more widely. Although the goal of treatment is to make patients “better” (or to help them cope with their problems), precisely what “better” means, and when we can reliably claim we have achieved this, is definitely less clear. This is partly because the “nature and causes of [mental] disorders are unclear”1; and partly, I would add, because, like beauty, getting “better” is in the eye of the beholder. Outcomes are very different when view-ed by the patient, the clinician, the family, the public health doctor, the health insurance company, or the pharmaceutical company marketing department. While there may be overlap, there is unlikely to be full agreement. Indeed, there may be no overlap between the patient and the pharmaceutical company marketing department, for example. Most psychotherapy research has focused on symptom reduction as determined by clinicians. Moreover, most systematic reviews and meta-analyses of the majority of mental health interventions, and therefore guidelines, use reduction in symptoms or some similar clinician-measured variable (such as relapse reduction) as key outcomes. Cuijpers highlights the shortcomings of symptom reduction as an outcome deriving from the clinician's perspective rather than from that of the patient or family. Nonetheless, it is important not to ignore how important symptoms are in the clinician-patient interaction. Symptoms are the clinician's interpretation and construction of the experiences that the patient describes to him. When the patient “gets better” , from his perspective, the experiences that made him seek help have disappeared; from the clinician's perspective, the patient's symptoms have abated. Using the full set of experiences/symptoms relevant to the clinician and patient is not a bad way of understanding outcomes. In this context, “symptoms” are much broader than those defined in DSM and ICD2. It is, however, an entirely different matter when, in the reified world of network meta-analyses, a single symptom becomes the proxy outcome for the entire experience of the illness. This can lead to unexpected and possibly unreliable conclusions. For example, network meta-analyses of antidepressants suggest that they work for depressed people over 18 years3 but not for people under 18 years4. For many reasons, it is likely that the “truth” is more complicated5, 6. Reducing statistical evaluation to one or two outcomes may lead us to seeing a couple of trees and missing the wood entirely. Nevertheless, in England, national mental health guidelines underpinned by the systematic review of outcomes, mainly based on symptom reduction, have highlighted the importance of psychological therapies within mental health. In recent years, the growth of services, such as early intervention in psychosis services and the Improving Access to Psychological Therapies (IAPT) programme (a primary care based treatment programme for common mental disorders), and of psychological treatments in children and young people's mental health services, has been based on the guidelines of the National Institute for Health and Care Ex-cellence (NICE), which mainly use symptom reduction to demonstrate improved outcomes. The use of symptoms-based outcome measures in routine clinical practice has become the cornerstone of the IAPT programme. Last year, IAPT services treated over a million people with common mental disorders. Although the use of symptom-based outcome measures has its flaws, having 95% paired outcome measures for a million or more patients per year makes this the most data-rich health programme in the world. Being able to demonstrate effectiveness in routine practice has led to a further expansion of IAPT to also provide mental health care for people with long-term physical health problems, so that we can see 1.5 million people with common mental disorders per year, and new mental health services are now monitoring outcomes routinely. In addition, economic outcomes are now of equivalent importance to clinical and patient-related outcomes. As Cuijpers alludes to, in the quality adjusted life years (QALYs), the economics of health care and quality of life are combined as a measure of cost utility/effectiveness. This approach, which tends towards the reification seen in network meta-analyses, has nevertheless allowed us to draw comparisons about the cost-benefit ratios between the treatment of depression using psychological approaches and the treatment of cancer with cytotoxic drugs and radiotherapy. Cuijpers does not, however, deal with some further important outcomes. One fifth of people with anorexia nervosa die prematurely, an outcome which has led the National Health Service England to invest an extra £30 million per year into the treatment of eating disorders in children and young people (psychological treatments are the only proven treatments for these disorders). In addition, suicide, arguably the most devastating outcome for families in mental health, does not figure in Cuijpers' review. To the extent that death and suicide are outcomes of mental health problems, they are also possible outcomes of any mental health treatments. Finally, it is worth spelling out how we can use outcomes in routine practice, not just to prove that patients are getting better, but also to add to the process of psychological therapies, at the level of the individual patients, the therapists, the teams and the organizations. For the individual patients, outcome measurement provides a collectively agreed measure of “success” (recovery, improvement, less distress) for them to use. Outcome measures can give them a chance to recognize change and can instil a sense of hope. For the therapists, measuring outcomes allows them to compare their success rates to other therapists and to measure their own improvement over time, and can be an important guide in supervision. Similarly, for the teams, outcome measurement can be used to benchmark their outcomes against others. It is a useful exercise for quality improvement and can help them recognize training needs and where to recruit in areas of weakness. At an organizational level, outcomes can underpin clinical and public health strategies and can be used to interrogate whether we are getting value for money. All this applies to psychological treatments just as it applies to medical and other interventions. We need to choose the outcomes to suit the need. In the end, the point of outcome measures in psychotherapy, or in any approach in mental health, and accounting for the different perspectives of the people involved, is that we can test out our theories about mental health, about psychotherapy and how each approach works, and our strategies for service delivery and change, and we can find out what the benefits are for particular groups of people. Without measuring outcomes, we do not have evidence. And without evidence, all we can do is jump to conclusions based on prejudice.