Last week I spent a couple of days in York, England exploring outcome measurement and valuation for Health Technology Assessment with academics from the Centre for Health Economics at the University of York. People attended from across the world and I sat beside colleagues from many countries including India, Ghana, Switzerland, Greece, Denmark, Spain and Germany. The world cup took on new significance!
Health outcomes involve changes in health status – changes in health of an individual or population, attributable to an intervention. Sometimes the population or group is defined because different outcomes are expected for diverse people and conditions. Measurement of health outcomes involves carrying out different measurements including, measurement of health status before the intervention, measurement of the intervention, and measurement after to try and relate the change to the intervention.
Health Technology Assessment (HTA) in its simplest form is about determining whether or not health services are safe and effective. The primary goals are to improve safety of healthcare; make decisions on treatment more consistent; ensure cost-effective treatments are utilized and to share information to assist with decision making (see http://www.hca.wa.gov/hta/Pages/index.aspx). Within HTA we try to determine if the benefit gained from the new treatment is greater than the benefit forgone through displacement.
Outcome measurement for decision making has an important role in patient reported outcomes. Firstly we design health care interventions around basic science and anticipated clinical effects. We then need to understand the clinical impact – such things as cancer progression or clinical interpretation. Finally, we need to understand the impact on patients. We can do this by measuring such things as subjective well-being or function e.g we could measure changes in quality of life in patients with end stage kidney disease, before and after and intervention, by using the Kidney Disease Quality of Life Questionnaire.
The building blocks of outcome measurement include:
Measurement – What is the impact of the disease? What is the impact of the interventions?
Individual preferences – Trading off length of life for quality of life; what weight is given to different aspects of health
Societal preferences – Relevant to disease or other characteristics
If an intervention is to be introduced there are different methods for valuing health and often it is quality of life that is measured. Health related quality of life is a patient’s subjective perception and not determined by a clinician. It is multidimensional and includes physical function, psychological health and social wellbeing. It can be measured using a variety of tools. Disease specific questionnaires can be used e.g. the Chronic Heart Failure Questionnaire; or generic health related quality of life tools which are non-preference based can be used such as the SF-36. Finally preference based tools such as the EQ-5D -5L can be used. The EQ-5D -5L is a very useful measure and recommended by the National Institute for Clinical Excellence as it allows for an economic evaluation where health benefits are expressed in terms of Quality Adjusted Life Years (QALYs). (See http://www.nicedsu.org.uk/EQ5D(2474845).htm)
So why is it important that we measure health outcomes? Measuring health outcomes allows us to make decisions about how to best care for our patients and outcome measures help us predict the patients who might benefit most from a particular intervention. It helps us identify any improvement after an intervention is provided. The effective use of outcome measures is an important aspect of clinical care and deciding which outcomes are relevant to a patient group and selecting appropriate measures of those outcomes requires an understanding of the clinical situation, as well as an understanding of the measurement properties of the outcome measures. Outcome measures can be important tools for guiding clinical decision making. However, to function well these tools must be used with skill and understanding.
So if this blog has sparked your interest and you want to know more about Outcome measurement and valuation have a look at the York Expert Workshops at http://www.york.ac.uk/che/courses/short/york-expert-workshops/