Towards greater bandwidth for standardised outcome measures

Abstract

An Editorial1The Lancet PsychiatryA good enough measure.Lancet Psychiatry. 2020; 7: 825Summary Full Text Full Text PDF PubMed Scopus (6) Google Scholar published in The Lancet Psychiatry responded to the call for standardisation in outcome measures made jointly by the National Institute of Mental Health (NIMH) and the Wellcome Trust that included the Patient Health Questionnaire-9 (PHQ-9). The Editorial concluded that “good enough” measures should be accepted, and pointed to the utility of the Body-Mass Index developed in the early 1970s as a model.1The Lancet PsychiatryA good enough measure.Lancet Psychiatry. 2020; 7: 825Summary Full Text Full Text PDF PubMed Scopus (6) Google Scholar The debate about and effort towards standardisation in outcome measures is not new. In 1970, as part of the NIMH's Outcome Measures Project, Irene Waskow and colleagues in the USA held a symposium to devise a core outcome battery to standardise outcome measurement in the psychological therapies. The results, published in 1975, aimed to make “a concerted effort to advance the development of systematic information concerning the efficacy of psychosocial therapies and the measurement of psychotherapeutic change”.2Waskow IE Parloff MB Psychotherapy change measures. US Government Printing Office, Washington, DC1975Google Scholar The core outcome battery comprised five measures, including an idiographic component. These efforts were overtaken by the arrival of the DSM, although they were rekindled in the mid-1990s in both the USA and the UK.3Barkham M Evans C Margison F et al.The rationale for developing and implementing core outcome batteries for routine use in service settings and psychotherapy outcome research.J Ment Health. 1998; 7: 35-47Crossref Scopus (159) Google Scholar The motivation for the development and adoption of common outcome measures is no different now to 50 years ago. However, being overly specific about measures such as the PHQ-9 runs the risk of freezing the field, as shown by the dominance for decades of the Beck Depression Inventory. With the PHQ-9 being free, comprising only nine items matching the DSM criteria for depression, and embedded in national delivery systems such as the Improving Access to Psychological Therapies programme in England, it is difficult to see it being replaced anytime soon. History has taught us that a dominant measure can remain for a generation. But the larger problem lies not in the motivation towards some form of outcome standardisation but rather in what it is that is standardised; in this case, monosymptomatic measures such as the PHQ-9. Rather than investing in such narrow measures, it might be better to invest in monitoring broader aspects of people's lives that include functioning, relationships, and quality of life. There are measures that carry such bandwidth, are informed by the views of practitioners or experts based on lived experience rather than diagnostic nosology, and that can also deliver cost-effectiveness data.4Evans C Connell J Barkham M et al.Towards a standardised brief outcome measure: psychometric properties and utility of the CORE-OM.Br J Psychiatry. 2002; 180: 51-60Crossref PubMed Scopus (556) Google Scholar, 5Keetharuth AD Brazier J Connell J et al.Recovering Quality of Life (ReQoL): a new generic self-reported outcome measure for use with people experiencing mental health difficulties.Br J Psychiatry. 2018; 212: 42-49Crossref PubMed Scopus (67) Google Scholar The example of the Body-Mass Index is a world away from investigating human psychological distress. After 50 years, it is time to move on from DSM-based derivatives and consider measures that draw on the broader experiences of people, the nature of their psychological distress, and its effect on their lives. I have previously been involved in the development of the Clinical Outcomes in Routine Evaluation-Outcome Measure (CORE-OM) and the Recovering Quality of Life (ReQoL) outcome measures. A good enough measureJuly, 2020, marked the 48th anniversary of the Body Mass Index (BMI), the omnipresent measurement in obesity research, still used by WHO as the standard for obesity statistics. Despite its limitations, the BMI is a stalwart tool owing to its ease of use and rule-of-thumb accuracy in linking obesity with disease. Since its inception, researchers have developed new measures and have gained a deeper physiological understanding linking obesity with poor health outcomes; but the BMI has been there, in study after study, linking an entire field and generations of scientists working towards better treatments. Full-Text PDF